Essentials Clinical Pearls of Surgery Chapter 5: Preop Care and Risk Assessment The American Society of Anesthesiology classes are ● Class I Healthy patient: limited procedure ● Class II Mild to moderate systemic disturbance ● Class III Severe systemic disturbance ● Class IV Life-threatening disturbance ● Class V Not expected to survive, with or without surgery Predictors of cardiac risk in surgical patients include the following: ● Major predictors ○ Unstable coronary syndromes ○ Recent myocardial infarction with evidence of important ischemic risk by clinical symptoms or noninvasive study ○ Unstable or severe angina ○ Decompensated congestive heart failure ○ Significant arrhythmias ○ High-grade atrioventricular block ○ Symptomatic ventricular arrhythmias in the presence of underlying heart disease ○ Supraventricular arrhythmias with uncontrolled ventricular rate ○ Severe valvular disease Intermediate predictors ● Mild angina pectoris (Canadian class I or II) ● Prior myocardial infarction by history or pathologic Q waves ● Compensated or prior congestive heart failure ● Diabetes mellitus Minor predictors ● Advanced age, abnormal ECG (left ventricular hypertrophy, left bundle-branch block, ST-T abnormalities), rhythm other than sinus (e.g., atrial fibrillation), loss functional capacity (e.g., inability to climb one flight of stairs with a bag of groceries) ● History of stroke ● Uncontrolled systemic hypertension Preoperative indicators for malnutrition: ● Anorexia, dysphagia ● Recent weight loss ● Recurrent nausea, vomiting, or diarrhea ● Malignancy (renal, liver, lung) ● Gastrointestinal disorders (inflammatory bowel disease, pancreatitis, fistulas) ● Drug dependency (i.e., alcoholism, illegal or prescription drugs) ● Dental difficulties ● Impoverished social status (homeless, disabled or elderly individuals living alone)
Clinical risk factors for perioperative deep vein thrombosis: ● Older than 40 years ● Prolonged immobility/paralysis ● Prior DVT ● Cancer ● Major surgery (pelvic, abdomen)
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Obesity Varicose veins Congestive heart failure Myocardial infarction Stroke Fractures of the pelvis, leg, hip Indwelling femoral vein catheters Inflammatory bowel disease Nephrotic syndrome Estrogen use Hypercoagulable states
Chapter 6: Fluid and Electrolyte Management The most common cause of metabolic alkalosis in surgical patients is nasogastric losses or vomiting. The peritoneal surfaces represent 50% of body surface area. During laparotomy, the expected evaporative fluid loss from the exposed peritoneum is 10 mL/kg/hr. Hyperphosphatemia may result from rhabdomyolysis due to muscle ischemia or crush injury. The stress response to surgery results in the release of glucagon, aldosterone, cortisol, and antidiuretic hormone. Tonicity rather than osmolarity determines water movement. Sodium determines volume, osmolarity, and tonicity of extracellular fluid. Rapid correction of hyponatremia may cause central pontine myelinolysis. Hypomagnesemia may cause hypokalemia, hypophosphatemia, and hypocalcemia. A very low urinary chloride concentration is a good indicator of extracellular fluid contraction from vomiting or nasogastric losses. Causes of metabolic alkalosis can be divided into those that are responsive to chloride and those that are unresponsive ( Table 6-6 ). Patients with chloride-responsive metabolic alkalosis usually have a contracted extracellular volume and chloride deficit, and a urinary chloride that is less than 10 mEq/L. Vomiting and high nasogastric outputs are common causes. The volume deficit stimulates sodium retention. The passively absorbed sodium in the proximal tubule requires an accompanying anion. Because a deficit of chloride exists, the anion available to meet this need is bicarbonate. In late stages of severe contraction alkalosis, hydrogen is exchanged for sodium, despite plasma alkalemia (paradoxical aciduria).
Chapter 7: Nutrition in Surgical Patients Always perform a nutritional assessment for each patient. general condition, any fatigue, and the ability to work and carry out daily activities. A key element is a history of altered or poor oral intake, looking for both poor macronutrient and micronutrient consumption. Patients with gastrointestinal symptoms such as anorexia, nausea, vomiting, or diarrhea for more than a 2week period will often have associated malnutrition. A history of poor wound healing is a concern. Recent unexpected weight loss is very important, and a weight loss of 10% or greater represents malnutrition. On examination, the patient may have temporal and interdigital wasting. The presence of ascites and ankle edema is seen with malnutrition, particularly protein both the disease and the surgical procedure decrease the albumin because of leaking of albumin from the vascular space and relative decreases in albumin production, making the serum albumin an unreliable nutritional measure.
Clinical assessment is the best tool. The metabolic response to surgery produces both calorie and protein malnutrition, termedmarasmus. Injury from either surgery, trauma, or complications such as sepsis produces a well-defined metabolic change in the host. The characteristics of the phenotypic change include (1) mobilization of glucose and the development of peripheral insulin resistance; (2) protein catabolism with mobilization of peripheral protein to support the increased protein requirements and to support hepatic gluconeogenesis; (3) hypermetabolism with an increased energy expenditure; and (4) salt and water retention with an expanding third space. Calculate the patient's feeding weight and nutritional requirements. For the average surgical patient, protein is set at 1.5 g/kg/day; total calories are set at 25 cal/kg/day, carbohydrates are set at 4 mg/kg/min, and lipids are no more than 20% of total calories. Enteral nutrition access is the best delivery system. Parenteral nutrition can be used with patients who cannot use the gastrointestinal tract, who are severely malnourished, or have a severe disease or injury resulting in malnutrition and/or a delay in the use of the gastrointestinal tract. Use transitional feeding from parenteral to enteral as soon as possible. The uptake of nutrients from the intestine will allow both the liver and the pancreas to control the levels of glucose and lipids, thus minimizing hyperglycemia and hyperlipidemia. In addition, enteral feeding reduces mucosal atrophy, which is thought to be associated with translocation of bacteria and toxins. Enteral feeding decreases enteral stasis and bacterial overgrowth, decreases biliary stasis and acalculous cholecystitis, and decreases gastric mucosal erosions. Avoid the refeeding and overfeeding syndromes. With the intracellular glucose uptake, a massive and rapid shift occurs of the extracellular electrolytes into the cell, repleting the low levels of potassium, phosphorus, magnesium, and manganese. The consequence is serious extracellular electrolyte abnormalities, resulting in arrhythmias and cardiac dysfunction and failure. In addition, the relatively low sodium and accompanying anemia will result in renal retention of fluid and sodium, adding to the syndrome producing congestive heart failure Other proteins will be glycosylated and become dysfunctional, such as cell-surface receptors on macrophages, neutrophils, and lymphocytes, and the immunoglobulins. Hyperglycemia, usually greater than 220 mg/dL, results in immunosuppression both at the cellular and humoral level, with a resultant increase in infections. The hyperlipidemia increases lipid uptake by the RES system and decreases bacteria and endotoxin clearance by the RES. The blood viscosity will increase, with microvascular sludging decreasing flow. Nutritional support is dynamic. Change it with changes in the patient's clinical state. The degree of obesity is measured by using the body mass index (BMI). Patients with a BMI greater than 35 and life-threatening comorbidities and those with a BMI greater than 40 are considered for surgery, only after a complete and complex preoperative workup. The standard bariatric operation is a gastric bypass. Gastric banding may be considered for lower BMIs, and a biliopancreatic procedure, for greater BMIs. Long-term close follow-up is required monitoring for nutritional, psychological, and surgical complications. Always know the patient's nutritional state going into surgery. Stop both enteral and parenteral nutritional support when going to surgery. With parenteral nutrition, avoid relative hypoglycemia when stopping the infusion before surgery. Use 10% dextrose to cover the patient.
Decide on the postoperative nutritional strategy before surgery. If you think of it, do something about it. Consider enteral access and intestinal function. Gastrostomies are practical, but if concerns with aspiration are present, then consider a jejunostomy. Jejunostomy feedings can be started in the postanesthesia recovery room, provided that the patient is hemodynamically stable. Always use a low rate such as 10 mL/hr. Malnourishment will affect the surgical approach, including wound closure. Secure both gastrostomies and jejunostomies to the abdominal wall. With ascites, avoid gastrostomies and jejunostomies, and consider using a nasoduodenal or nasojejunal feeding tube if the need is for the short term. Restart PN when the patient is hemodynamically stable, and monitor for the surgical stress–induced hyperglycemia. Gastric banding places an adjustable band around the stomach just below the esophagogastric junction, creating a small gastric pouch. Gastric bypass creates a small isolated gastric pouch, which is anastomosed to a limb of jejunum, either a short limb of 100 cm or a long limb of 150 cm or greater. The biliopancreatic limb is anastomosed at this point to create the Roux-en-Y. The biliopancreatic operation with a duodenal switch creates a sleeve gastric pouch of 250 mL anastomosed after the pylorus to a long alimentary limb. The biliopancreatic limb is anastomosed to the alimentary limb, leaving a common channel or limb of 100 to 150 cm before the ileocecal valve.
Chapter 8: Blood and Bleeding: Transfusions, Control, and Prevention Fibrinogen levels <100 mg/dL prolong bleeding. The vitamin K–dependent clotting factors are II, VII, IX, and X. FFP or vitamin K reverses warfarin (Coumadin). Protamine reverses heparin. Bleeding patients whose platelets have been impaired by aspirin or nonsteroidal anti-inflammatory drugs may need platelet transfusions, no matter what the platelet count. Bleeding after cardiopulmonary bypass may be due to inadequate neutralization of heparin. Giving FFP in this setting may worsen the bleeding because FFP provides antithrombin III. Microvascular bleeding often indicates a platelet defect. Hypothermia impairs platelet function and can prolong bleeding. Red blood cells that have been warmed to >40 oC before infusion or are infused through lines containing D5W are likely to hemolyze. Blood should never be infused with medications or with any solution other than saline. Wound drainage contains fibrinolytic substances. Red blood cells from shed blood usually should be washed before use. Extensive tissue injury may result in significant blood loss without obvious bleeding. A single injury to the thigh may result in 2 to 3 L of blood loss into the large crushed muscle mass.
Chapter 9: Wound Healing Cutaneous sutures should be removed within 1 week to avoid “railroad tracks.” At 1 week, wounds have 3% of the strength of prewound skin. At 3 weeks, wounds have 10% of prewounding strength. At 6 weeks, wounds have 35% to 50% of prewounding strength. Clean wounds can be achieved by means of dressing changes, water irrigation, mechanical débridement, and detergents. Hypertrophic scars develop within the original wound margins. Keloids spread beyond the original boundaries of the wound. In areas where skin is loose, wound contraction may contribute 90% or more to the wound-healing process. The three phases of wound healing are inflammation, proliferation, and remodeling. PMNs are not necessary for wound healing. Wounds are fully epithelialized after 24 hours; patients may bathe after this time. Wounds that are moist epithelialize most quickly. Occlusive dressings best serve this purpose. Factors that impair healing include aging, tissue ischemia, malnutrition, edema, radiation therapy, steroids, collagen vascular disease, and diabetes Ninety percent of all leg ulcers are due to venous insufficiency. In the absence of cellulitis or abscess, pressure sores almost never cause bacteremia and fever.
Chapter 10: Prevention and Management of Surgical Infections Antibiotic prophylaxis: ● •No need for prophylactic antibiotics for class I wounds unless a prosthesis is to be implanted. Use a first-generation cephalosporin ● •Class II cases: ○ Use first-generation cephalosporin for elective cholecystectomy. ○ Use first- or second-generation cephalosporin for acute cholecystitis. Use first- or second-generation cephalosporin for gastric surgery. Use a mechanical preparation with oral antibiotics (erythromycin base, neomycin) the night before surgery and a second-generation cephalosporin the day of surgery for colon surgery. Class III cases: trauma, perforated bowel: second-generation cephalosporin or ampicillin/gentamycin/flagyl Use vancomycin only in penicillin-allergic patients or if methicillin-resistant Staphylococcus aureus (MRSA) is documented. All antibiotics must be given within 1 hour of the incision. Did the patient receive prophylactic antibiotic before the incision was made? In soft-tissue infections, débridement must extend to normal tissues.
Keep the skin open in contaminated cases (classes 3 and 4). The seven intraperitoneal spaces where abscesses can form: ● •Right gutter ● •Left gutter ● •Right subphrenic space ● •Subhepatic space ● •Left subphrenic space ● •Pouch of Douglas ● •Interloop space
Chapter 11: Trauma ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●
Increase in diastolic pressure is the first blood pressure change seen in hypovolemia. When present, it means class II hemorrhagic shock (loss of ∼15%–30% of blood volume). Systolic hypotension is a sign of class III hemorrhagic shock (loss of 30%–40% of blood volume). Agitation is another sign of shock. Profound hypotension and apathy are signs of class IV hypovolemic shock (loss of >40% of blood volume). A normal 70-kg man has approximately 5 L of blood volume (70 mL/kg). Decorticate posturing includes flexion of the upper extremity (the arm makes a “C” for “de Corticate”). Decerebrate posturing includes extension and external rotation of the upper extremity (the arm makes an “S,” like the soft c in “de Cerebrate”). The signs of pericardial tamponade include Beck's triad (hypotension, JVD, muffled heart sounds), tachycardia, pulsus paradoxus, and elevated CVP. Options for managing splenic rupture include observation, embolization, splenorrhaphy, and splenectomy. Hemodynamic stability and evidence of ongoing bleeding are the most important factors in choosing a treatment strategy for solid-organ injury. Airway always comes first. In penetrating trauma, mortality is a function of vascular injury. Address the bleeding first. In blunt trauma, stop the active bleeding by any means practical, including via angioembolization, packing, or repair, before addressing injuries that are not contributing to blood loss. When solid-organ bleeding is controllable only by packing, then pack. Catheters placed during emergencies should be replaced when the emergency has passed.
Chapter 12: Critical Care ● ● ●
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Sudden onset of adult respiratory distress syndrome (ARDS) may reflect pathology below the diaphragm. ARDS = (Sudden onset) + (Fi O 2/P O 2 <300) + (Diffuse infiltrate) + (No CHF) Weaning from the ventilator requires ○ Adequate mechanical respiratory function ○ Adequate ventilation ○ Adequate oxygenation To work up delirium, remember the mnemonic WWHHHIMP: Withdrawal, Wernicke's encephalopathy, Hypoglycemia, Hypoxia, Hypertension, Intracerebral process, Meningitis, and Poisons (drugs). Catabolic patients require 1.02 g/kg of protein per day. If the gut works, use it.
Chapter 13: Burns ● ● ● ●
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Tangential excision is the preferred method, removing thin layers of eschar until viable tissue, characterized by punctate capillary bleeding, is encountered. Methods for covering large wounds include widely meshed skin grafts, temporary coverage with cadaver allografts, synthetic skin substitutes, or cultured epidermal cells. Infiltration of burn wounds or skin graft donor sites or both with saline solution containing epinephrine can facilitate excision or harvest and markedly reduce bleeding. Deep partial-thickness burns should be treated with excision and skin grafting to speed healing, reduce the possibility of infection, and improve the ultimate functional and cosmetic result for the patient. Mortality for major burns is now low. A young adult with burns of 80% to 90% TBSA has a 50% survival. Smoke inhalation worsens survival because of pneumonia and multiple organ failure. Three types of inhalation injury are carbon monoxide poisoning, upper-airway burns, and lower-airway chemical injury. Estimate burn extent by using the “rule of nines”: Head, arms: 9% TBSA each; anterior torso, posterior torso, each leg: 18% TBSA each. The palm of the patient's hand is 1% TBSA. Parkland formula for fluid resuscitation: 4 mL lactated Ringer's × body weight (kg) × burn size (%TBSA). This tells you where to start resuscitation, which is subsequently adjusted to patient response. Urine output is the single most important parameter of adequate fluid resuscitation. Remember that edema is progressive throughout fluid resuscitation. The patient should be repeatedly evaluated for compartment syndromes involving the extremities or torso. Nutritional requirements for burn patients may exceed twice normal. Whenever possible, use enteral nutrition: 30 to 35 nonprotein kcal/kg/day; 1.5 to 2.0 gr protein/kg/day. Fat should not exceed 35% of diet. Indications for surgery: any burn that does not demonstrate eschar separation and epidermal budding within 14 days of injury.
Chapter 14: Acute Abdomen ● ● ● ● ●
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The workup of patients with acute abdominal pain Physical examination A detailed physical examination includes assessment, inspection, auscultation, palpation, percussion, and rectal/pelvic examination. Laboratory values CBC, electrolytes, LFTs, amylase, lipase, and urinalysis can all provide important information in the workup of patients with abdominal pain. A pregnancy test (urine or blood) is mandatory in all women of childbearing age. Radiographic tests Imaging studies such as plain, supine, and upright radiographs, ultrasound, CT, angiography, barium studies, and endoscopy are useful tools for the surgeon in determining a cause of a patient's abdominal pain. Laparoscopy versus laparotomy: Laparoscopy is often used for unclear diagnoses in patients with signs of an acute abdomen. Laparoscopic approaches can be quickly converted to a standard laparotomy, if necessary. Peritonitis/perforation: Patients with signs of peritonitis or found to have perforation of a hollow viscus need surgical intervention. Appendicitis: Pain that localizes to right lower quadrant accompanied by anorexia, nausea, and vomiting is a classic symptom. Acute pancreatitis: Patients with acute pancreatitis rarely needs surgical intervention but rather supportive medical care. Cholecystitis: Laparoscopic approach has been proven safe in both acute and chronic settings. Diverticulitis: Patients with diverticulitis will require emergency surgery with signs of perforation and significant abscess formation. Bowel obstruction: Small-bowel obstructions can be initially treated with a nonoperative course
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including bowel rest and nasogastric suction. Mesenteric ischemia: Pain out of proportion to physical examination is pathognomonic for mesenteric ischemia. Ruptured aortic aneurysm: Early detection and intervention are the keys for patient survival. Gynecologic causes: Ruptured ectopic pregnancy is the most life-threatening gynecologic emergency.
Chapter 15: Appendicitis ● ●
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The classic history of diffuse periumbilical pain migrating to become more-intense right-lowerquadrant (RLQ) pain is present in only 50% of cases. Frequency of signs and symptoms: Abdominal pain, 95% to 99%; anorexia, 90%; elevated white blood cell (WBC) count (or simple shift) plus fever, 90%; nausea, vomiting, and/or diarrhea, 85%. Rebound tenderness is defined as voluntary guarding with sudden release after deep palpation. Rovsing's sign is defined as referred tenderness and guarding in the RLQ with palpation in the LLQ. Psoas sign is seen when pain is elicited with flexion of the hip or extension against resistance. Fever higher than 38ºC and WBC more than 20,000 often denotes perforation. Appendicitis has an extensive differential diagnosis. Administer prophylactic antibiotics before incision. Operative approaches include oblique (McBurney) incision, transverse (Rocky-Davis) incision, midline laparotomy, and laparoscopy. Location of the appendix may vary between the right lower quadrant (RLQ), pelvic, or retrocecal positions. The tip of the appendix may lie in the RUQ or LLQ. The base of the appendix is located at the junction of the three tenia. The appendiceal artery lies posterior to the cecum or terminal ileum. If appendicitis is not present, a thorough search for other pathology is important (Meckel's, pelvic inflammatory disease, ovarian cyst, etc.) In advanced appendicitis or perforation, search for concomitant abscess (pelvic, paracolic gutter, intraloop). Consider open packing of the wound for advanced and perforated appendicitis.
Chapter 16: Hernias ● ● ● ● ● ●
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An acutely incarcerated hernia is a surgical emergency. The posterior or preperitoneal approach is best for recurrent hernias (open or laparoscopic). The recurrence rates for inguinal hernias are direct, 5%–10%, and indirect, 1%–5%. The use of a prosthesis for herniorrhaphies is mandatory only when a suture repair would be under undue tension. Ventral, incisional hernias frequently occur because of wound infection, obesity, malnutrition, and other factors that lead to poor wound healing. The boundaries of the inguinal canal are (1) anterior, the external oblique aponeurosis; (2) posterior, the transversalis fascia and transversus abdominis aponeurosis; (3) inferior, the inguinal and lacunar ligaments; and (4) superior, the internal oblique and transversus abdominis muscle and aponeuroses. Indirect inguinal hernias come through the internal or deep inguinal ring, whereas direct inguinal hernias come through the posterior wall of the inguinal canal (transversalis fascia). Two frequently used types of inguinal herniorrhaphies are the Bassini repair, in which the transversus abdominis aponeurosis and the internal oblique aponeurosis (conjoined tendon) superiorly are sutured to the inguinal ligament inferiorly, and the Cooper's ligament (McVay) repair, in which the conjoined tendon superiorly is sutured to Cooper's ligament inferiorly. The boundaries of femoral canal are (1) anterior, the iliopubic tract and inguinal ligament; (2) posterior, Cooper's ligament; (3) medial, the lacunar ligament; and (4) lateral, the femoral vein. Hematomas and infections occur in 1%–2% of inguinal herniorrhaphies.
Chapter 17: Biliary System ● ● ● ● ● ● ● ●
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How to perform safe dissection Gallbladder is retracted superiorly while the redundant infundibulum is retracted laterally to expose the cystic duct—gallbladder junction. Dissect only the gallbladder—cystic duct junction. Avoid dissecting the common bile duct unless common bile duct exploration is anticipated. Clearly visualize and confirm all structures before ligating and dividing; always be attentive to the likelihood of biliary and arterial anomalies and variations. Learn to expect the unexpected: ductal and arterial anatomic variability is the rule rather than the exception. Calot's triangle is defined by the cystic duct laterally, the common hepatic duct medially, and the liver superiorly. Painless jaundice is an otherwise healthy patient is carcinoma of the biliary system until proven otherwise. After laparoscopic cholecystectomy, patients should have minimal pain and be able to eat. Nausea, vomiting, and increasing abdominal pain are often early warning signs of a postoperative bile leak or other complication Ultrasound examinations performed for biliary pathology: Need to know ○ presence or absence of stones ○ gallbladder wall thickening ○ presence or absence of common bile duct dilatation Patients admitted with acute cholecystitis should ingest nothing by mouth (NPO), given antibiotics, and operated on during that admission Fractionate the total bilirubin into direct and indirect components to determine obstructive (i.e., surgical) causes of jaundice. High direct suggests obstructive cause for jaundice. High indirect suggests nonobstructive (e.g., hepatic) cause.
Chapter 18: Liver ● ● ● ● ● ● ●
The liver is made up of eight segments, with the anatomic division between the left and right lobe as a line between the gallbladder fossa inferiorly and the vena cava superiorly. Liver-function tests actually reflect liver dysfunction, with the exception of the prothrombin time (PT). Administration of fresh frozen plasma to correct liver-induced coagulopathy before bedside procedures is costly and not proven to be effective. Solitary congenital cyst in the liver means only one. Any patient with the “tell-tale” second cyst has polycystic liver disease by definition. Portocaval shunts for Budd-Chiari syndrome must drain the liver and splanchnic circulation to be successful. Of the benign liver tumors, only hepatic adenoma requires routine resection to prevent bleeding or malignant transformation. Metastatic colon cancer is biologically privileged, in that cure can be obtained in carefully selected patients with aggressive surgical removal.
Chapter 19: Portal HTN ● ●
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When treating portal hypertension, hope for the best, but be prepared for the worst. Any operation undertaken on patients with cirrhosis and portal hypertension can lead to substantial blood loss. The dissection of the inferior venal cava and portal vein is greatly facilitated through the use of a blunt, smooth instrument (e.g., Yankauer suction tip). Often numerous varices are seen within the retroperitoneum and porta hepatis; these can bleed quite substantially. Liberal use of ligatures or electrocautery or both is a must. When undertaking the small-diameter H-graft portacaval shunt, the first anastomosis to be constructed is that between the graft and the vena cava. It is important to remove a wedge of the
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vena cava wall when making the venotomy to assure adequate outflow from the graft. Care must be used to avoid injury to the bile duct, gallbladder, and hepatic artery. Check intraoperative pressures before and after shunting. After the shunt is completed, seek a decrease in portal vein pressure of at least 10 mmHg and a portal vein–to–vena cava gradient of less than 10 mmHg. The presence of a thrill in the vena cava cephalad to the shunt will confirm shunt patency. Altered mental status in patients with cirrhosis and portal hypertension (encephalopathy) is a warning sign of poor hepatic reserve and would generally contraindicate shunting until resolved. Doppler ultrasound of the portal vein is useful in determining portal vein patency. Computed tomography angiography and visceral angiography also are used. A portal vein with good flow and caliber is required for shunting. Patients with portal hypertension with an acute upper gastrointestinal hemorrhage should be admitted to the intensive care unit. The patient's airway is secured, and the patient is appropriately resuscitated with crystalloid, packed red blood cells, and fresh frozen plasma. Invasive monitoring (e.g., Swan-Ganz catheter) may be helpful in guiding resuscitation. An octreotide infusion should be initiated early. Expedite upper endoscopy, and a Sengstaken-Blakemore (S-B) tube should be readily available. Review S-B tube management so that its use will be appropriate, safe, and effective. Thrombocytopenia is common in patients with portal hypertension. The inclination to transfuse platelets should be resisted, as platelet transfusions will have little effect because of portal hypertension and splenic sequestration.
Chapter 20: Spleen and Hematologic Disorders ● ● ● ● ●
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Splenic ligaments include the splenophrenic, splenorenal (lienorenal), splenocolic, and gastrosplenic. Accessory spleens are present in 10% to 40% of patients. The most common indications for splenectomy in United States are immune thrombocytopenic purpura, trauma, and iatrogenic injury. The primary functions of the spleen are blood filtration, “pitting” of erythrocytes, and immunity. Warm-antibody autoimmune hemolytic anemia (AIHA): Immunoglobulin G (IgG)–coated red blood cells are destroyed in the spleen. The spleen is removed when patients fail to respond to steroids, with a 60% success rate. Splenectomy is not indicated for cold-agglutinin (IgMmediated) AIHA. Immune thrombocytopenic purpura: The spleen produces antiplatelet antibodies and destroys IgG-coated platelets. Steroids form the first line of therapy; splenectomy is the second line, with a 70% to 80% response rate. Steroids, intravenous immunoglobulin, or anti-RhD may be given preoperatively to increase the platelet count. Nonoperative management of spleen injuries requires hemodynamic stability, no other injuries warranting laparotomy, intact hilar vessels, and minimal transfusion requirements. Overwhelming postsplenectomy infection (OPSI): fulminant, flulike symptoms progress to septic shock in 24 hours; half die. Lifetime incidence is about 3% to 5%, typically in children or in adults with hematologic diseases, and within 2 years of splenectomy. Streptococcus pneumoniae, Haemophilus influenzae, and Neisseria meningitides are the most common bacteria in OPSI. Splenomegaly is usually due to hematologic diseases, liver disorders, and infection. Massive (>1500 g) splenomegaly is most commonly due to myelofibrosis, non-Hodgkin's lymphoma, chronic lymphocytic leukemia (CLL), and hairy cell leukemia.
Chapter 21: Colon and Anorectum ● ● ● ●
Watershed areas of the colon (poor blood supply): splenic flexure (Griffith's point), rectosigmoid junction (Sudeck's point) The strongest layer of the bowel wall: submucosa Requirements of a good bowel anastomosis: Good blood supply, tension free, air tight (for rectal anastomosis tested with a proctoscope) Two structures to be identified and avoided during right hemicolectomy: duodenum, right ureter
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Distal point of resection of sigmoid for diverticular disease: coalescence of teniae coli Always perform a thorough, bimanual examination of the liver when operating for colorectal cancer. A good oncologic resection of a colon cancer involves proximal ligation of the named vessel(s) supplying the length of bowel being removed. A good oncologic resection of a rectal cancer involves total mesorectal excision (for mid and distal rectal tumors) and a proximal ligation of the inferior mesenteric vessels, just distal to the left colic. Three most common locations for internal hemorrhoids: right anterior, right posterior, left lateral Successful treatment of a fistula-in-ano requires identification of the internal opening. Proper treatment of a thrombosed external hemorrhoid involves excision of the hemorrhoid, not incision, and expression of the clot. Causes of colonic obstruction (in order): cancer, diverticular disease, volvulus Cecal volvulus (in general): younger patient, radiograph shows “coffee-bean” pointing to left upper quadrant (LUQ), treatment is surgical Sigmoid volvulus (in general): elderly patient, radiograph shows “bent inner tube” pointing to right upper quadrant (RUQ), treatment is endoscopic decompression followed by elective surgery (if patient is not high risk) The recurrence of a sigmoid volvulus is as high as 60% after endoscopic decompression. Chemotherapy recommended for colon cancer stages: Tany, N1or2, M0; or Tany, Nany, M1 Chemotherapy and radiation therapy recommended for rectal cancers: T3or4, N0, M0; or Tany, N1or2, M0 Most common cause of rectal bleeding: hemorrhoids Most common presenting symptom of colorectal cancer: blood per rectum From 5% to 10% of patients with a positive fecal occult blood test will have colon cancer. 50% of patients with colon cancer will have a positive FOBT. Incidence of rectal bleeding in patients with diverticulitis: less than 5% A diverticular abscess can be treated successfully with percutaneous drainage about 75% of the time. An attack of diverticulitis should be documented by CT scan or elevated WBC and treated and allowed to defervesce before elective surgery is considered. Virtually all colon cancers start as an adenomatous polyp. Colorectal cancers most commonly metastasize to the liver and the lung. Three most common causes of rectal pain: fissure, abscess, thrombosed external hemorrhoid One third of drained perirectal abscesses will subsequently form a fistula-in-ano.
Chapter 22: Irittable Bowel Disease (IBD) ●
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In sharp contrast to ulcerative colitis (UC), in which the disease is confined to the colorectal mucosa, Crohn's disease (CD) is characterized by a segmental inflammation that can affect any portion of the alimentary tract. The lesions associated with CD typically extend transmurally beyond the mucosa and submucosa, reflecting perhaps a more complex inflammatory process. Ulcerative colitis usually is first seen with bloody diarrhea, abdominal pain, and fever. Extraintestinal manifestations of UC are observed in a number of organ systems, including articular disorders, lesions of the skin and oral cavity, inflammatory disorders of the eye, liver and biliary tract disorders, thromboembolic disease, and vasculitis. The principal categories of drug treatment for UC include symptomatic antidiarrheal and antispasmodic agents, sulfasalazine and its analogues, corticosteroids, immunosuppressive antimetabolites, and certain antibiotics. Standard medical therapy for active CD depends largely on the location, extent, and severity of the disease, and consists mainly of the same drugs used in the treatment of UC, such as corticosteroids, anti-inflammatory agents, and immunomodulators. Indications for surgical intervention for ulcerative colitis (UC) include unrelenting hemorrhage, fulminating acute UC that is unresponsive to therapy, obstruction from stricture, suspicion or demonstration of colonic cancer, toxic megacolon, somatic and sexual growth in children, and
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intractability. The primary indication for initial surgery in Crohn's disease (CD) of the small intestine is obstruction due to fibrosis and stricture. Subtotal colectomy with ileostomy and Hartmann closure of the rectum is the operation of choice when an urgent situation arises in a critically ill patient with Crohn's colitis. Subtotal colectomy with ileostomy is the procedure of choice in the emergency setting, or if the diagnosis of UC, as opposed to CD, cannot be clearly established. Colectomy, mucosal proctectomy, and endorectal ileal pouch–anal anastomosis (IPAA) has become the operation of choice for patients with refractory UC. Although the major early operative morbidity after IPAA is bowel obstruction, the most frequent late complication in patients undergoing IPAA is ileal pouch dysfunction or pouchitis, which has been reported to occur in up to 50% of patients undergoing this procedure for UC.
Chapter 23: Motility Disorders ● ● ● ● ●
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Complete small-bowel obstruction usually requires urgent laparotomy because of the risk of closed-loop obstruction and intestinal gangrene. Partial small-bowel obstructions can usually be treated nonoperatively initially with nasogastric (NG) suction and hydration. Cecal dilatation of 9 cm or greater requires urgent colonoscopic decompression or surgical management, whether it is due to obstruction or to pseudo-obstruction. Factors that increase the duration of postoperative ileus include preoperative bowel distention, intraperitoneal dissection, and surgery on the colon or rectum. The two anal sphincters are the internal sphincter, a thickening of the smooth muscle layer of the rectal wall, and the external sphincter, striated muscle arising from the levator muscles. Only the external sphincter is under voluntary control. In the normal recovery from postoperative ileus, the small intestine resumes peristalsis first, followed by the stomach. The colon recovers last and may take 3 to 5 days to resume function. In a postoperative patient with prolonged ileus and possible bowel obstruction, abdominal computed tomography scan with luminal contrast is the most useful test. In a patient with prolonged postoperative ileus, remember to check the medication list for narcotics and other drugs that inhibit transit; also check the electrolytes and the serum albumin. The first test to rule out intestinal obstruction is usually a flat and upright radiograph of the abdomen. The most reliable radiographic sign of small-bowel obstruction is decreased gas in the colon. Truncal vagotomy or resection of the ileum will cause postprandial (bile salt) diarrhea in many patients. Resins that bind bile salts (e.g., cholestyramine) are effective treatments.
Chapter 24: Pancreas (No pearls) Ranson's Criteria for Severity of Acute Pancreatitis: On Admission
At 48 Hr
Age >55 yr
Hematocrit decrease >10 percentage points †
WBC >16,000 cells/mm 3
Serum calcium <8 mg/dL
Serum glucose >200 mg/dL
Base deficit >4 mEg/L
Serum LDH >350 units/L
BUN increase >5 mg/dL †
AST >250 U/dL
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Arterial pO 2 <60 mmHg
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Fluid sequestration >6 L ‡
Chapter 25: Small Intestine · Most common etiologies for small-bowel obstruction: adhesions, malignancy, hernia, inflammatory bowel disease, volvulus · Most common causes of ileus: neurologic injury/disease, hypokalemia, infection, opiates and anticholinergics, postoperative state · Management of small-bowel obstruction: fluid resuscitation, nasogastric tube, early surgery · Clinical indicators of obstruction with strangulation: steady pain, tachycardia, fever, absent bowel sounds, bloody stool, leukocytosis, acidosis · Most common indications for surgery in Crohn's disease: obstruction, perforation, bleeding, intractability · Factors preventing spontaneous closure of fistulas: malnutrition, sepsis, inflammatory bowel disease, cancer, radiation, obstruction of the intestine distal to the origin of the fistula, foreign bodies, high output, and epithelialization of the fistula tract · Causes of acute mesenteric ischemia: embolus, thrombus, vasospasm, venous thrombosis · Problems with prolonged total parenteral nutrition use: catheter sepsis, venous thrombosis, osteoporosis, cholelithiasis, kidney failure, liver failure, cost, increased mortality · Anatomy: jejunum is proximal two fifths of small intestine; ileum is distal three fifths. The jejunum has a larger circumference and a thicker wall, and its mesentery contains more fat than does that of the ileum. The strongest layer of the intestinal wall is the submucosa. · Complications of intestinal resection: anastomotic leak, fistula, stricture, vitamin B 12 and bile salt malabsorption for ileal resection, short-bowel syndrome · Criteria for intestinal viability: (1) normal color, (2) peristalsis, and (3) marginal arterial pulsations. In borderline cases, use Doppler probe or visualize fluorescein dye in the bowel wall under ultraviolet illumination. · Meckel's diverticulum: Found in 2% of population, located within 2 feet of ileocecal valve, 2% symptomatic, 2 inches in length · Most common benign neoplasms of the small intestine: adenomas, leiomyomas, and lipomas. The most common malignant neoplasms: adenocarcinomas, carcinoids, lymphomas, gastrointestinal stromal tumors · Strategies for avoiding short-bowel syndrome: resect no more intestine than necessary, stricturoplasty, preserve colon, preserve ileocecal valve
Chapter 26:Stomach and Duodenum · Two motility types occur in the stomach: receptive relaxation and accommodation in the fundus of the stomach, and true peristalsis in the antrum and pylorus. · Chronic infection with Helicobacter pylori is a risk factor for gastric carcinoma. · Indications for surgery for a duodenal ulcer include intractability, hemorrhage, perforation, and obstruction. · The early dumping syndrome refers to a complex of symptoms including tachycardia, diaphoresis, dizziness, light-headedness, and weakness, which typically occur within 30 minutes of eating. · The key to management of stress erosion is prevention. · No evidence indicates that a total gastrectomy confers any additional survival benefit over partial gastrectomy in gastric cancer. · Most surgeons agree that a 4- to 6-cm margin is necessary in gastric cancer because of submucosal spread of the tumor. · Vagotomy and antrectomy is the operation for duodenal ulcers with the lowest recurrence. · Truncal vagotomy and pyloroplasty is the ideal operation for the septic, unstable, or high-risk patient in whom a quick, low-morbidity procedure must be done for complications of peptic ulcer disease. · Newer approaches to duodenal ulcer include laparoscopic proximal gastric vagotomy and truncal vagotomy of the posterior vagus nerve with an anterior seromyotomy.
Chapter 27: Esophagus GERD Complications of gastrointestinal reflux disease (GERD) include esophageal stricture, aspiration pneumonia, Barrett's esophagus, and esophageal adenocarcinoma.Treatment options for GERD include dietary/lifestyle modifications, medical therapy with protein-pump inhibitors (PPIs), and surgical fundoplication, usually performed laparoscopically.AchalasiaThe diagnosis of achalasia requires the finding of aperistalsis on an esophageal-motility study.Treatment options for achalasia include botulinum toxin (Botox) injection, pneumatic esophageal dilation, and surgical therapy with esophageal myotomy, usually performed laparoscopically.Esophageal CancerAdenocarcinoma is now more common than squamous cell cancer in the United States.Evaluation should include barium swallow as the initial study, followed by upper endoscopy to confirm the diagnosis; computed tomography and endoscopic ultrasonography are useful studies for staging the cancer. AnatomyRich submucosal vascular plexus allows for long-segment mobilization of the esophagus with low risk of causing ischemia. Extensive submucosal lymphatics allow cancer spread to remote lymphatic drainage basins.Nissen FundoplicationFundoplications should be short (2 cm) and floppy, requiring mobilization of the short gastric vessels and performance of the wrap around a dilator (>50F) to ensure maximal floppiness.Heller MyotomyMyotomy involves complete division of the fibers of the lower esophageal sphincter and should be 6 to 8 cm in length, including 2 cm onto the cardia of the stomach.Partial fundoplication (Dor or Toupet) is performed to prevent gastroesophageal reflux disease after myotomy.EsophagectomyA gastric conduit is preferred for esophagectomy in adults, whereas an isoperistaltic left colon segment is the best esophageal replacement in children. The blood supply for the gastric conduit is based on the right gastroepiploic artery, which must be carefully preserved during mobilization of the stomach.
Chapter 28: Disorders of the Trachea, Chest Wall, Pleura, Mediastinum, and Lung (No pearls)
Chapter 29: Acquired Cardiac Disorders The stages of a standard operation for coronary bypass grafting can be divided into four quarters: (1) open the chest and harvest the conduit, (2) prepare for cardiopulmonary bypass, (3) form the bypass grafts, and (4) wean from cardiopulmonary bypass, and close the chest.Usual preparation for cardiopulmonary bypass involves placement of cannulae into the arterial circulation and systemic venous circulation to flow blood to the body. Cardioplegia cannulae are inserted to flow preservative solution to the heart. Finally, the patient must be completely anticoagulated with heparin before cardiopulmonary bypass can be initiated.The complications of cardiopulmonary bypass in general are emboli (either solid or air), aortic dissection, hypoperfusion, hyperperfusion, inflammatory response, thrombocytopenia, adult respiratory distress syndrome, and renal failure.The conduction system of the heart crosses the interventricular septum adjacent to the aortic valve. This location is near the membranous septum, which lies under the commissure between the right and noncoronary cusps. Damage to the conduction system here with valvereplacement surgery can necessitate placement of a permanent pacemaker.Mitral valve annuloplasty usually moves the posterior portion of the annulus toward the left ventricular outflow tract. One of the dangers of mitral valve repair is to move the anterior leaflet coaptation point too far into this outflow tract, thereby causing obstruction to the flow of blood from the ventricle. This is called systolic anterior motion of the mitral(SAM). The indications for coronary artery bypass graft (CABG) can be split into categories of longevity and quality of life. Left main stenosis greater than 50%, three-vessel disease with ejection fraction less than 45%, and two-vessel disease with 90% proximal left anterior descending artery stenosis all improve longevity in surgically treated patients as compared with medically treated patients. Problems such as angina (which limits normal activities), unstable angina, postinfarct angina, intolerance of medical therapy for angina, and failure of percutaneous intervention are all indications for CABG, which improves quality of life.The classic symptoms of aortic stenosis can help to predict the natural history of the disease
if left untreated. Angina is associated with a 5-year average survival. Syncope is associated with a 3-year average survival. Congestive heart failure has the worst prognosis, with a 2-year survival.Valve choice is a difficult problem. Mechanical valves are durable and have excellent hemodynamic properties; however, they require life-long anticoagulation. Tissue valves do not require anticoagulation; however, they are not as durable, and the patient may be faced with the prospect of reoperation when the valve fails. Therefore the patient's long-term expected survival is balanced with the risk of coumadin versus reoperation.Prolonged anticoagulation with coumadin may carry significant problems, such as a 1% to 2% per year risk of thromboembolic or bleeding complications, and this effect is additive over a patient's lifetime. Coumadin is not good for the very elderly (older than 85 years), patients who are noncompliant or who will not maintain medical follow-up, patients with underlying progressive liver disease, patients with significant intracranial pathology, patients with a known bleeding disorder, or patients with medical illnesses that may require other surgical procedures.
Chapter 30: Congenital Cardiac Disorders ●
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In general, congenital heart defects should be repaired early to avoid pulmonary vascular occlusive disease, to prevent the consequences of severe right and left ventricular volume or pressure overload, and to reduce damage to other organs. Symptomatic patients should undergo surgical repair at the time of diagnosis, and asymptomatic patients should do so at the age of 6 to 12 months. Young age by itself does not add risk to surgery. A shunt is considered hemodynamically significant when the flow in the pulmonary circulation is greater than or equal to 1.5 times the flow in the systemic circulation (that is, when Qp/Qs ≥ 1.5). If possible, a complete repair of any congenital anomaly should be attempted during initial surgery, because operative mortality and morbidity rates associated with complete repairs are low, additional procedures become unnecessary, and the adverse effects of continued abnormal physiologic mechanisms are prevented. Palliative procedures, such as systemic-to-pulmonary shunts and pulmonary artery banding, should be reserved for special circumstances. The repair of most congenital cardiac anomalies requires the use of cardiopulmonary bypass and cardioplegic arrest. Deep systemic hypothermia (15ºC to 18°C) and total circulatory arrest are frequently necessary to afford optimal exposure in neonates and small infants with complex anomalies. Atrial septal defects (ASDs) and most ventricular septal defects (VSDs) are approached via the right atrium. ASDs can be closed with a continuous suture or with a patch. VSDs are almost invariably repaired with a patch. Complete repair of tetralogy of Fallot includes closure of the VSD and elimination of the right ventricular outflow tract obstruction. The arterial switch operation is the procedure of choice for most patients with transposition of the great arteries. A resection with end-to-end anastomosis is the preferred technique for most patients with coarctation of the aorta. In neonates, severe aortic stenosis is best managed initially with percutaneous balloon valvuloplasty. In older children, balloon valvuloplasty or surgical valvotomy should be attempted to allow growth of the aorta.
Chapter 31: Thyroid ●
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Patients with Graves' disease for whom surgery is indicated include those with very large glands who cannot be treated adequately with radioactive iodine and those who are allergic to thionamides or whose hyperthyroidism cannot be controlled with these drugs. Thyrotoxic patients who are to be treated surgically should be adequately treated first with antithyroid medication (thionamides) to render them euthyroid. Patients who require an emergency thyroidectomy and are thyrotoxic should be treated preoperatively for 5 days with dexamethasone, iopanoic acid, propanolol, and propylthiouracil. Ionizing radiation is associated with the development of thyroid cancer, and the majority of radiation-induced tumors are of the papillary type. Five prognostic factors for patients with thyroid cancer include metastases, age, completeness of surgery, and invasiveness of the tumor. The pyramidal lobe is a remnant of the thyroglossal duct. The arterial blood supply of the thyroid arises from two major sources: the inferior thyroid artery, which originates from the thyrocervical trunk, and the superior thyroid artery, which is the first branch of the external carotid artery. A delphian lymph node is an enlarged prelaryngeal node that is occasionally associated with thyroid cancer. enous drainage includes the superior and middle thyroid veins, which empty into the internal jugular vein, and the inferior thyroid vein, which also empties into the jugular vein or the innominate vein
Chapter 32: Parathyroid ● ● ● ● ● ● ● ● ●
Primary hyperparathyroidism (PHPT) and malignancy account for 90% of hypercalcemic cases. Classic radiographic manifestations of osteitis fibrosa cystica include subperiosteal resorption of the distal phalanges, a salt-and-pepper appearance of the skull, and tapering of the distal clavicles. Primary hyperparathyroidism may occur in association with multiple endocrine neoplasia (MEN) I and IIA syndromes. PHPT is caused by parathyroid carcinoma in fewer than 1% of cases. The superior parathyroid glands are derived from the fourth branchial pouch and may be located anywhere from the upper border of the larynx to the lower pole of the thyroid. The inferior parathyroid glands are derived from the third branchial pouches and may be located anywhere from the angle of the jaw to the pericardium. The inferior glands are most commonly located on the anterolateral or posterolateral surface of the lower thyroid gland. The majority of ectopic glands are located within the thymus. The parathyroids receive their blood supply primarily from the inferior thyroid arteries; however, sometimes anastomoses occur between the superior and inferior thyroid arteries.
Chapter 33: Adrenals ● ● ● ● ● ● ●
Pheochromocytomas occur in association with several familial disorders including multiple endocrine neoplasia IIa (MEN-IIa), MEN-IIb, von Hippel–Lindau, and neurofibromatosis. Rule of 10s for pheochromocytoma: 10% bilateral, 10% occur in children, 10% extra-adrenal, 10% malignant, 10% incidental, and 10% recur. A unilateral aldosterone-producing adenoma (APA) is the most common type of primary aldosteronism and is treated with surgical removal. Adrenal venous sampling is considered the gold standard for differentiating a unilateral APA from primary adrenal hyperplasia. Specific signs of Cushing's syndrome include central obesity, proximal muscle weakness, wide purple striae, spontaneous ecchymoses, and facial plethora. Patients with adrenocortical carcinoma (ACC) have a poor prognosis, with a 5-year survival of less than 50%. Complete surgical resection is the only effective and potentially curative treatment for ACC.
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The adrenal glands, along with the kidney, are enclosed by Gerota's fascia and are surrounded by fat. The arterial blood supply to the adrenal glands is from three main sources: the superior suprarenal artery, which is a branch from the inferior phrenic artery; the middle suprarenal artery, which arises from the aorta; and the inferior suprarenal artery, which is a branch from the renal artery. The right adrenal vein is short, exits the medial aspect of the glans, and drains directly into the inferior vena cava. The left adrenal vein leaves the gland anteriorly and drains into the left renal vein.
Chapter 34: Pituitary ● ● ● ● ● ● ●
The cavernous sinus borders the pituitary gland and contains the internal carotid artery and cranial nerves III, IV, V, and VI. The blood supply to the pituitary is maintained by the superior and inferior hypophyseal arteries. The surgical cure rate for a patient with acromegaly due to a macroadenoma is 50%. Prolactin levels associated with a prolactinoma are usually greater than 100 ng/mL. Medical therapy with a dopamine agonist (bromocriptine or cabergoline) is the preferred treatment for prolactinomas. Measuring the insulin-like growth factor (IGF-1) level is the best screening test for acromegaly. Trans-sphenoidal adenomectomy is the preferred first-line therapy for patients with acromegaly
Chapter 35: Lymphatic and Venous Systems ●
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The lymphatics are a unidirectional, closed-loop system, which returns fluid and protein that have traveled from the vascular capillaries into the interstitial space and back to the venous system. The thoracic duct of the lymphatic system enters the vascular system at the junction of the left subclavian and jugular veins. A number of lymphatic ducts enter the venous system on the right side. Primary lymphedema is characterized as congenital (younger than 1 year at onset), praecox (1–35 years), or tarda (older than 35 years). Secondary lymphedema is the result of obliterative cancer therapy in Europe and North America and most commonly is caused by filariasis worldwide. Duplex ultrasonography can provide both anatomic and physiologic information relevant to venous function. It is the most widely used modality to evaluate the venous system and to determine treatment. The treatment of choice for chronic lymphedema is conservative and nonsurgical, consisting of elevation, massage, compression, exercise, and skin care. Surgical procedures are rarely performed. The venous system is composed of three anatomic parts: deep veins and superficial veins, as related to muscle fascia, and perforating veins, which connect these two systems. Most patients with chronic venous insufficiency and venous ulcers have a mixture of superficial, deep, and perforating vein incompetence.
Chapter 36: DVT and PE ● ● ● ● ● ● ●
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The majority of cases of deep vein thrombosis (DVT) are asymptomatic. DVT occurs frequently in patients undergoing orthopedic, abdominal, and pelvic surgery. Younger patients in whom DVT develops will often have a predisposition to hypercoagulopathy. Pulmonary embolism should be high on the differential diagnosis in any postoperative patient experiencing respiratory symptoms or sudden collapse. Most deep vein thromboses (DVTs) in the surgical patient occur on the OR table. Prophylaxis is critical in prevention of DVT/pulmonary embolism (PE). Subcutaneous heparin (5000 units), given before surgery and continued (twice daily) postoperatively until full mobilization is achieved, is effective. Alternatively, low-molecularweight heparin may be used to the same effect. Intermittent calf-compression devices also are effective in prevention of DVT.
Chapter 37: Peripheral Arterial Occlusive Disease ● ● ●
Five factors for successful arterial reconstruction are good inflow, good outflow, good bypass or endarterectomy, good surgeon (operative technique), and an honest coagulation system. Bleeding that does not stop in the OR rarely stops in the recovery room. Never say “Oops,” because patients under anesthesia remember such things.
Chapter 38: Aneurysms ● ● ● ● ●
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The primary cause of death of patients with an abdominal aortic aneurysm (AAA) is rupture. AAA expansion rates increase as a function of the size of the AAA. The most consistent results for monitoring growth of an AAA come from using the computed tomography scan. The most common etiologies for thoracoabdominal aneurysm formation are atherosclerotic medial degeneration, followed by dissection. Factors predicting neurologic complications after surgical repair of thoracoabdominal aneurysms are prior proximal aneurysm repair, presence of aortic dissection, duration of aortic cross-clamp time, oversewing of intercostal arteries, and hypotension. Femoral and popliteal artery aneurysms account for 90% of peripheral aneurysms. The mere presence of a popliteal or femoral aneurysm and not the size is an indication for surgical repair because of the high risk of thromboembolic complications. Most abdominal aortic aneurysms are found below the renal arteries. No back-bleeding or brisk back-bleeding from the inferior mesenteric artery once the abdominal aneurysm is opened indicates that good collateral circulation to the left colon exists. Endovascular repair of an abdominal aortic aneurysm requires frequent computed tomography or duplex evaluation, looking for late technical complications. Spinal fluid drainage or spinal cooling or both have been shown to reduce the incidence of postoperative neurologic complications. The most frequent complication after thoracoabdominal aneurysm repair is respiratory failure. Femoral artery aneurysms are repaired by excision, and popliteal artery aneurysms are repaired by ligation and bypass.
Chapter 39: Cerebrovascular Disease ● ● ●
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Stroke is the third leading cause of death in the United States and the primary cause of adult disability. The two major types of stroke are hemorrhagic and ischemic. The circle of Willis connects the anterior and posterior circulation of the brain and balances the inflow from the carotid and vertebral arteries to the anterior, middle, and posterior cerebral arteries. The most common mechanism of cerebral ischemia is emboli from an extracranial site. The absolute risk reduction of a stroke after carotid endarterectomy in symptomatic patients is 17%. The common facial vein frequently marks the bifurcation of the carotid artery in the neck. Carotid artery dissection is treated with anticoagulation for 3 to 6 months. Cranial nerve injury after carotid endarterectomy is uncommon and can occur in 2% to 8% of patients. Vagus, hypoglossal, and glossopharyngeal nerves are the nerves that can be injured. Ipsilateral stroke after carotid endarterectomy should not occur in more than 2% to 3% of patients. The major cause of death after carotid endarterectomy is myocardial infarction and occurs in 1% to 2% of patients.
Chapter 40: Breast Cancer ● ● ● ● ● ● ● ● ●
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According to the American Cancer Society guidelines, annual screening mammography begins at age 40 years. Lumpectomy is not appropriate for multicentric cancers, persistent positive margins, or patients who received prior radiation therapy to the breast. Axillary node dissection is indicated if the sentinel node is positive or for axillary node recurrence after sentinel node surgery. Chemotherapy before surgery is indicated for locally advanced and inflammatory breast cancer and for patients with matted axillary nodes. Proven prognostic factors are tumor size; number of positive axillary lymph nodes; estrogen- and progesterone-receptor status; and age/menopausal status of the patient. Long thoracic nerve injury causes a “winged scapula.” Intercostalbrachial nerve injury causes pain or paresthesias of the axilla or arm or both. Injection sites for sentinel node surgery include the subareolar area, the skin overlying the tumor site, and the walls of the tumor cavity or tissue immediately surrounding the tumor. Proper handling of the lumpectomy or excisional biopsy specimen includes anatomic orientation, specimen mammography if the lesion is not palpable and was radiographically localized preoperatively, and request for appropriate tumor markers. Removal of hard or enlarged nodes or both is part of sentinel node surgery, even with no tracer uptake.
Chapter 41: Principles of Surg Onc ● ●
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Surgical oncology is a specialized interest discipline within the realm of general surgery that focuses on the diagnosis and management of the cancer patient. Major areas of interest included diagnosis and treatment of solid tumors, management of acute and chronic problems related to malignancy, and guidance of patients through the obstacle course of specialists and special procedures to reach the optimum treatment. The surgeon functions as the captain of the ship and aggressively pursues early diagnosis using all of the currently available techniques and assists the patient in the decision-making process about the optimum surgical and adjuvant therapy. The surgeon frequently is involved in the screening process for common tumors such as breast and colorectal cancer. The surgeon facilitates the multimodal treatment provided to the patient by inserting vascular access devices for chemotherapy and “PEG” tubes for management of nutrition (operative bypass may be needed). The surgeon conducts the long-term post-op surveillance of cancer patients to facilitate early diagnosis and treatment of recurrence or palliation. Early diagnosis of solid tumors is facilitated by use of fine needle aspiration cytology or core needle biopsy of palpable masses. Ultrasound can aid the surgeon in diagnosis of palpable breast thickening or lumps. Cysts or solid masses have distinctive ultrasound characteristics, and ultrasound directed FNA or core biopsy can provide histologic confirmation. Excisional biopsies of suspicious tumors in the breast, head and neck, and soft tissue should be fully oriented by marking sutures prior to exam by the pathologist. For melanoma or SCC of skin, proper biopsy techniques will ensure adequate histology. Fullthickness biopsy into subcutaneous tissue by core, punch, or incisional technique is needed. For sarcoma, initial FNA followed by core biopsy or proper oriented incisional biopsy may be done. Mucosal tumors require cup biopsy via endoscope and breast requires FNA, core stereotactic, or open biopsy. Proper management of biopsied tissue is important:tissue for lymphoma assessment or for electron microscopy, or special antibody or molecular tests should be examined fresh. Sentinel node biopsy optimizes lymphatic staging for melanoma, breast cancer, skin cancers, and certain GI tumors and commonly involves lymphscintigraphy to pinpoint the nodal site.
Chapter 42: Diseases of the Bones and Joints ●
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The most common bacteria associated with hematogenous osteomyelitis in children are the grampositive cocci Staphylococcus aureus and streptococci, whereas in adults they are gram-negative bacteria, such as Escherichia coli, Pseudomonas, and Salmonella. Magnetic resonance imaging is the most sensitive means of detecting osteomyelitis. Inflammatory arthritis is a disorder that affects the synovial joints and may occur secondary to autoimmune or metabolic disorders. Analysis of synovial fluid is the primary means by which inflammatory arthritis is differentiated from noninflammatory arthritis. Osteoarthritis is classified into two groups, primary (idiopathic) osteoarthritis and secondary osteoarthritis, and is the most common noninflammatory arthritic condition associated with significant disability, work loss, and hospitalizations. Anteroposterior and lateral radiographs of the hip and an anterior view of the pelvis are necessary for the proper evaluation of hip disorders. In patients with diabetes mellitus, damage to the peripheral nerves is the primary effect on the foot. Indications for surgery for osteomyelitis include the presence of an abscess or necrosis of the bone and soft tissue and the need for drainage. In the surgical management of rheumatoid arthritis, synovectomy may be beneficial early in the course of the disease, before joint destruction has occurred, because it may provide symptomatic relief and delay disease progression. Either resection arthroplasty or replacement arthroplasty is indicated if the disease is more advanced. Surgical options for the management of hip disorders include arthroscopy, arthrodesis, osteotomy, and arthroplasty. Total knee arthroplasty is indicated in patients who have radiographic evidence of advanced intraarticular disease and have disabling knee pain and other symptoms that cannot be managed successfully with nonoperative treatment.
Chapter 43: Hand Surgery ●
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The peak incidence of distal radius fractures is in patients age 60 to 70 years. In this age group, the usual mechanism of injury is a fall onto the outstretched hand. In young patients, the usual mechanism is a high-energy trauma, and associated injuries are frequently found. Carpal tunnel syndrome is characterized by pain, paresthesia, and numbness in the palmar radial aspect of the hand. Zone I extensor tendon injuries, such as mallet finger and swan-neck deformity, involve the terminal insertion of the conjoined lateral bands at the level of the distal interphalangeal joint. From 30% to 50% of phalangeal fractures are open, and more than half of these open fractures occur in the workplace. After phalangeal fracture, early mobilization of the fingers is important to prevent finger stiffness Longitudinal incisions are commonly used through dorsal skin because they allow extensile approaches and because the resultant scar is easily tolerated in this loose, redundant skin. Incisions through volar skin, however, should never be longitudinal, because the ensuing scar formation will cause flexion contractures. For this reason, zigzag incisions of the volar skin are preferred. Although free skin grafts are usually well accepted on the dorsum of the hand, they are rarely indicated on the palmar aspect, because they cannot supply the requisite sensation and cannot withstand the repetitive shear forces imparted during grip. If conservative management of carpal tunnel syndrome is ineffective, surgical release of the transverse carpal ligament is indicated. Zone II injuries of the flexor tendon are generally considered the most challenging to treat, given the difficulty of repairing both tendons in close opposition within the tendon sheath.
Chapter 44: Soft Tissue Injury ● ● ●
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The rotator cuff is composed of the tendons of the supraspinatus, infraspinatus, teres minor, and subscapularis muscles. Symptoms of shoulder instability are more frequently seen in athletes involved in overhead sports activities than in the general population. In all cases of acute dislocation of the shoulder, a thorough assessment of the neurovascular status of the limb must be done before attempts at reduction. Vascular injuries occur more frequently in older patients after an acute dislocation and may result in ischemia of the extremity. Magnetic resonance imaging is the most sensitive and specific study for diagnosing full-thickness and partial-thickness rotator-cuff tears, cuff degeneration, and tendinopathy. Most meniscal tears of the knee result from twisting or rotational forces during weight-bearing or sporting activities. Knee instability secondary to an anterior cruciate ligament (ACL) tear will frequently lead to a meniscal tear. Tears of the ACL most often result from a noncontact injury in which a pivoting, decelerating, or cutting maneuver takes place. ACL tears are frequently accompanied by other ligament or soft tissue injuries about the knee. Ankle sprains are the most common athletic injury. An inversion of the ankle typically causes damage to ligaments in the lateral ligament complex. After the reduction of an anterior or posterior dislocation, it is necessary to assess the stability of the shoulder and to reassess the neurovascular status of the extremity. If a shoulder dislocation occurs in association with avulsion of the rotator cuff, early surgery is indicated to remove interposed bone fragments and soft tissues. Anterior cruciate ligament (ACL) reconstruction reliably restores ACL function, and arthroscopyassisted surgery is currently the standard technique used for ACL reconstruction.
Chapter 45: Fractures ●
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Pathologic fractures are found in an area of bone that has been weakened by a disease process. These fractures commonly occur after some trivial injury and may occur spontaneously. Traumatic fractures result from a substantial impact on the bone. Stress fractures result from repeated low-level stress that exceeds the strength of the bone. Common fracture patterns include spiral, oblique, transverse, compression, avulsion, segmental (two separate fractures), comminuted (three or more fragments), and greenstick (incomplete) fractures. Fractures are described according to their location as proximal-, middle-, or distal-third fractures. They also are described as intra-articular or extra-articular fractures. Fractures are described by their alignment, displacement, and angular deformity in terms of the relation of the distal fragment to the proximal fragment. Because the thoracolumbar junction is the most mobile segment, the majority of spinal injuries occur at this level. Fractures of the clavicle most commonly result from a direct fall onto the shoulder. These fractures involve the middle third in most of the cases. Fractures of the proximal humerus are common injuries. The most frequent cause is a fall in an elderly patient with osteoporosis. In younger patients, high-energy injuries account for most fractures of the proximal humerus. Fractures of the pelvis can result directly from blunt trauma or indirectly from forces transmitted through the lower extremity. The fractures can be classified on the basis of their anatomic location, mechanism of injury, or stability. The incidence of hip fractures is highest in elderly white women. Risk factors include smoking, inactivity, osteoporosis, dementia, and the use of psychotropic medications. Tibial plateau fractures most often result from a fall, a motor vehicle collision, or an accident in which a pedestrian is struck by the bumper of a car.
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Surgical management of thoracolumbar injuries is indicated if the patient has an unstable spine or has progressive or complete neurologic deficit. Indications for open treatment of clavicle fractures include open fractures and injuries to the subclavian vessels. The goal of surgical treatment of hip fractures is to provide stability for appropriate healing and early mobilization, because early full weight bearing will limit loss of function and reduce postoperative complications. Femoral shaft fractures are best treated with intramedullary nails, because their use results in union in more than 95% of cases.
Chapter 46: Pediatric Ortho ●
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In children, fractures have the remarkable ability to remodel because of concurrent longitudinal growth. Treatment generally involves closed reduction and casting to maintain alignment while the bones heal. However, if the fracture is displaced, surgical intervention may be necessary to restore articular congruity. If fractures are found in an infant who is not yet walking, child abuse should be considered. The most common long-bone fractures seen in abused children are fractures of the humerus, tibia, and femur. Scoliosis is characterized by lateral deviation and rotation of the spinal column. Developmental dislocation of the hip is the most common hip disorder affecting children. Slipped capital femoral epiphysis is a disorder in which the proximal femoral epiphysis becomes displaced on the femoral neck. Pigeon toe, or in-toeing, may be the result of a rotational disorder of the lower extremities. Physical examination is important to rule out a disorder or delineate the cause of the disorder. In infants younger than 1 year, a common problem is metatarsus adductus, or adduction of the forefoot at the level of the tarsometatarsal joints. Clubfoot consists of ankle equinus, heel varus (inversion), forefoot adduction, and forefoot equinus. If a periosteal abscess is present or if the patient has not responded to antibiotic treatment, surgical treatment should be performed to decompress and débride the bone. In children with chronic osteomyelitis, surgical intervention is required to débride necrotic infected bone, and adjuvant antibiotic therapy is necessary to effect remission. Severe cases of in-toeing caused by tibial torsion can be corrected surgically with a supramalleolar osteotomy.
Chapter 47: Management of Pts. with Neurosurgical Diseases ●
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Signs of increased intracranial pressure (ICP) on head computed tomography (CT) scans are midline shift, compression or enlargement of the cerebral ventricles, and effacement of basal cisterns. Cerebral vasospasm after subarachnoid hematoma occurs between days 3 and 20; it peaks on day 7. Angiographic spasm occurs in 50% to 70% of patients; symptomatic spasm, in 30%. The mortality rate is 7%. ICP monitoring is appropriate in severe head injury patients (Glasgow Coma Scale, 3–8) with an abnormal CT scan, or a normal CT scan if two or more of the following are noted on admission: SBP, <90 mmHg Age older than 40 years Unilateral or bilateral motor posturing Immediate and complete physiologic resuscitation with avoidance of arterial hypotension or hypoxia in patients with severe head injury is the single most important factor improving outcome in this patient group. Treatment of patients with severe traumatic brain injury with steroids is not indicated. A recent prospective, randomized multicenter trial showed that the mortality of patients with traumatic brain injury who received high-dose dexamethasone infusion was increased compared with that
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of a control group. In patients with incomplete spinal cord injury, bone or other material in the spinal canal compressing the spinal cord should be removed operatively if the patient does not improve with conservative treatment or deteriorates neurologically. Operating on patients who have complete spinal cord lesions has not been shown to improve their function. Therefore indications for spine-stabilization surgery in this patient group are to improve their capacity to participate in rehabilitation and pain control. Stable thoracolumbar spine fractures are treated with an orthosis, such as a molded thoracolumbar sacral orthosis (TLSO). Unstable thoracolumbar spine fractures with neurologic deficit frequently should undergo surgical stabilization. Posterior approaches are usually preferred, but surgical decompression and vertebral body resection sometimes require access via an anterior, transthoracic, or transabdominal approach. Antibiotic-coated ventriculostomy catheters have been shown to reduce the rate of infections associated with intracranial (ICP) monitoring. A ventricular catheter connected to an external strain-gauge device is the most accurate and costeffective way of measuring ICP. It also allows therapeutic drainage of cerebrospinal fluid (CSF). Parenchymal monitors for fiberoptic monitoring of brain-tissue pressure are also accurate but more expensive, and they do not allow CSF drainage. Recently introduced combined catheters allow CSF drainage as well as continuous uninterrupted monitoring of ICP via fiberoptic or strain-gauge technology.
Chapter 48: CNS and Spinal Degenerative Diseases and Infections ●
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The role of neurosurgery in the workup of patients with HIV infection is very limited. An invasive biopsy can usually be avoided with appropriate diagnostic workup including imaging studies such as contrast MRI. Artificial cervical and lumbar disks have been introduced for the treatment of patients with cervical radiculopathy, myelopathy, or chronic disabling lower back pain. These procedures have the potential to replace fusion surgery, which has been considered the standard of care for some of these disorders. The advantage of artificial disks is that they preserve motion at the affected segment and may prevent degenerative disk disease at adjacent levels.
Chapter 49: Neoplasms ● ●
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Treatment of brain tumors depends particularly on the type of tumor, the location, and the degree of progression of disease. Treatment often combines surgery, radiotherapy, and chemotherapy. The most common presentation of brain tumors overall is slow progressive neurologic deficit, usually motor weakness. This is followed by headaches in approximately 50% of patients and seizures in 25%. Headaches and nausea/vomiting are the most common presenting symptoms in posterior fossa tumors. Magnetic resonance imaging with and without gadolinium is the imaging study of choice for brain tumors, especially for tumors in the posterior fossa. The role of conventional, open surgery for certain brain tumors has been challenged by advances made with radiosurgery. Today, radiosurgery—with either gamma knife or cyberknife technology—is an accepted first-line treatment for solitary cerebral metastases or acoustic neuromas smaller than 3 cm. More frequently, radiosurgery can be used as an adjunct to open surgery after partial resection of a brain tumor. In patients who are medically stable and with a reasonable life expectancy, spinal epidural metastases should be surgically resected. If signs and symptoms of spinal instability are noted, such as radiographic evidence of spinal cord compression, progressive neurologic deficit, pain, or deformity, resection should be followed by instrumentation. In the absence of these findings, radiosensitive tumors can be radiated as a first-line treatment, but the patients must be monitored closely.
Chapter 50: Otolaryngologic diseases (ENT) ● ● ● ● ● ● ● ● ● ●
Sensation for the external ear is from the facial, vagus, trigeminal, and third cervical root nerves. The most frequent organisms in acute otitis media are Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis. Acquired cholesteatoma most often begins in the pars flaccida. Transverse temporal bone fractures are less common than longitudinal or oblique fractures, but are associated with a higher risk of facial nerve injury. The most common tumor of the cerebellopontine angle is acoustic neuroma. Tympanostomy tubes are placed in the anteroinferior aspect of the tympanic membrane. The chorda tympani arises from the facial nerve and traverses the middle ear, passing between the malleus and the incus. In the middle ear, the facial nerve is dehiscent in about 50% of people. The internal auditory canal transmits the superior and inferior vestibular nerves, the cochlear nerve, and the labyrinthine artery. Acoustic neuromas typically arise from the intracanalicular vestibular portion of the eighth cranial nerve but have no predilection for either the superior or the inferior branch.
Chapter 51: Head and Neck Oncologic Surgery ● ● ● ● ● ● ● ● ● ●
Pleomorphic adenoma is the most common tumor of the parotid. Inverting papilloma is a benign tumor of the paranasal sinuses that has the potential to become malignant. The stage of the cancer is the most important factor in predicting survival. Encapsulation distinguishes schwannoma from neurofibroma. Nasopharyngeal cancer has been associated with Epstein-Barr virus. Removal of all lymph nodes and sparing of the spinal accessory nerve only is referred to as type I modified radical neck dissection. A glottic carcinoma with vocal cord fixation is considered a T3 lesion. A neck mass in a patient without infectious symptoms should be evaluated with endoscopy to rule out a primary mucosal malignancy of the upper aerodigestive tract. Surgery for adenoid cystic carcinoma of the parotid requires sacrifice of the facial nerve because of the tendency of this cancer to invade neurovascular structures. Healthy vascularized tissue in the form of a free flap may be needed to reconstruct a large defect in a previously irradiated tissue bed.
Chapter 52: Peds Otolaryngology ● ● ● ● ● ●
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The most significant risk of tonsillectomy in children is postoperative hemorrhage. The literature reports an occurrence of approximately 2% to 4%. The two most common indications for tonsillectomy in children are recurrent infection and tonsillar hypertrophy. The three organisms most frequently cultured from middle ear infections in children include Streptococcus pneumoniae,Haemophilus influenzae, and Moraxella catarrhalis. Second branchial arch anomalies are the most common and represent 90% of branchial cleft cysts and associated sinuses. The most common malignant tumor of the neck in children is lymphoma. The blood supply to the tonsil includes (1) facial artery (tonsillar branch), (2) dorsal lingual artery, (3) ascending palatine artery, (4) lesser palatine artery, and (5) ascending pharyngeal artery. The chorda tympani nerve innervates the anterior two thirds of the tongue. The facial nerve innervates the stapedius muscle, which is attached to the stapes. The second branchial cleft sinus tract runs lateral to the carotid bifurcation; it passes between the internal and external carotid arteries. The tensor veli palatini, innervated by the trigeminal nerve, opens the eustachian tube.
Chapter 53: Facial Plastic and Reconstructive Surgery ●
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The best tissue to use in replacing lost tissue is adjacent tissue. For a defect of the cheek skin, for example, rotating adjacent cheek skin into the defect will usually provide a better aesthetic outcome than repairing the area with a skin graft from the thigh. Many local skin flaps have been developed to facilitate the transfer of adjacent tissue. These include the note flap, the rhomboid flap, the rotation advancement flap, and the bilobed flap. The geometry of these flaps is fascinating, and their applications are quite varied. Autologous tissues are preferable to synthetic or other implants. When cartilage is needed for a repair, it is better to borrow from the conchal bowl of the ear, the rib, or the septum than to use a synthetic material that will have a greater risk of infection and extrusion. Straight lines occur rarely in the human body. Thus straight-line scars may be revised to be longer but to have a curved and broken course to help camouflage them. If a patient complains of significant pain or discomfort after rhytidectomy, it is neccessary to remove the dressing and check for a hematoma, as this will be the most common cause. When a skin graft is placed, it receives nutrients and oxygen through three distinct stages: (1) imbibition (graft absorbs wound exudate); (2) inosculation (vascular buds in the wound connect to preexisting and new vascular channels in the skin graft); and (3) revascularization (new vessel growth). In repair of mandible and midface fractures, wherever possible, make certain the patient's teeth are in proper occlusion at the outset of the case. This allows proper alignment of fractured fragments. When this is not possible, correct reduction can sometimes be accomplished by working down off of stable bone from the skull.
Chapter 54: Newborn and Pediatric Perioperative Care ●
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The fetal circulatory system uses the ductus venosus, the foramen ovale, and the ductus arteriosus to shunt oxygenated blood preferentially to the brain and upper body; these shunts close at or shortly after birth. The oxyhemoglobin dissociation curve for fetal hemoglobin is shifted to the left, because of lower 2,3-DPG binding by fetal hemoglobin. Total body water and extracellular fluid decrease between fetal life and adulthood, whereas intracellular water increases. The functional immaturity of the newborn kidney predisposes the neonate to hypernatremia. Metabolic alkalosis is caused by electrolyte loss and may occur with prolonged gastric suctioning or vomiting; metabolic acidosis is usually the result of poor tissue perfusion and lactic acidosis. Parents are less troubled about the length of their child's incision than by its width and contour irregularities. Parents will inspect the dressing you place on their child's wound and inevitably judge the skill and carefulness of the surgery that preceded it.
Chapter 55: Pediatric Trauma and Burns ●
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Maintenance fluids - Infant 0–10 kg =100 mL/kg D5 0.2NS with KC1 10 mEq/500 mL - Next 10 kg =50 mL/kg D5 0.45NS with KC1 20 mEq/1000 mL - Adult =30 mL/kg D5 0.45NS with KC1 20 mEq/1000 mL Resuscitation fluids - Infants and children = 20 mL/kg LR × 2, then PRBCs 10 mL/kg prn - Adults =1000 mL LR × 2, then PRBCs 10 mL/kg prn The pediatric airway is more anterior, shorter, and more fragile than the adult airway. Cardiac output in children is dependent primarily on heart rate. Corollary: Tachycardia usually indicates hypovolemia. Optimal management of closed head injury includes prevention of secondary brain injury. Prolonged arterial spasm is the most common presentation of pediatric vascular injury. The duration of submersion in a near-drowning accident is the most important factor associated
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with intact survival; survival after prolonged submersion (>5 minutes) is closely related to water temperature. A child's trachea is soft and pliable; use care when handling or incising it. Insertion of central venous catheters in children is the same as that for adults, except that the tolerance for error is less. A child's chest wall is thin, and the chest cavity is small; use care when inserting chest tubes. Hemodynamic status is the most accurate predictor of the need for transfusion or operative management or both of a pediatric solid-organ injury. A child with a lap-belt mark and an abdominal computed tomography scan showing free fluid, but no solid organ injury, has a hollow viscous injury until proven otherwise. Children - Galveston Lactated Ringer's 5000 mL/m 2 BSA burn + 2000 mL/m 2, ½ during the first 8 hr after burn, other 1/2 over next 16 hr period Adults - Parkland Lactated Ringer's 4 mL/kg/% burn, 1/2 during the first 8 hr after burn, other 1/2 over next 16 hr period
Chapter 56: Pediatric Head, Neck, and Thoracic Disorders ● ● ● ● ● ● ● ● ●
Infants are obligate nose breathers; obstruction of one or both nasal airways by a nasogastric, endotracheal, or feeding tube (or a combination of these) may impair breathing. Anterior cervical lymphadenopathy is usually viral or bacterial; posterior cervical lymphadenopathy is less common and more often associated with systemic disease or neoplasia. Infants with a posterolateral congenital diaphragmatic hernia are at risk for persistent pulmonary hypertension of the newborn (PPHN), as a result of bilateral pulmonary hypoplasia. PPHN is potentiated by hypoxia, acidosis, and hypothermia; it increases right-to-left shunting and exacerbates hypoxia and acidosis; prevention is the key. An infant's airway is small, easily traumatized, and highly prone to edema formation; significant loss of lumen diameter is accompanied by stridor and tachypnea. Thyroglossal duct cyst excision includes excision of the central portion of the hyoid bone, to assure that all ductal remnants are removed. Breast masses in prepubescent girls are usually observed, to avoid injury to the breast bud; those in postpubescent women are usually excised to obtain a diagnosis and allay fear. Repair of pectus excavatum is primarily cosmetic; it greatly enhances self-image and has been shown to improve exercise tolerance. When repairing a posterolateral congenital diaphragmatic hernia, remember that the diaphragmatic defect represents incomplete development of the third muscle layer of the chest wall; dissect the margin with care, and patch the diaphragm often.
Chapter 57: Pediatric GI, Abd Wall, Inguinal, and Scrotal Disorders ● ● ● ● ● ● ● ● ● ●
Know the differences in presentation, diagnosis, and management of pure esophageal atresia versus esophageal atresia with tracheoesophageal fistula. Bilious vomiting always deserves attention; bilious vomiting in a newborn requires investigation. Do not attribute the symptoms of abdominal pain, anorexia, nausea, and vomiting to gastroenteritis without first asking yourself, “Could this be appendicitis?” Neonatal jaundice beyond age 2 weeks must be investigated, especially if the direct bilirubin level (conjugated fraction) is greater than 1 mg/dL. Be able to list several different types of the most common omphalomesenteric duct malformation. Most postoperative problems begin in the operating room. Corollary: Antibiotics cannot compensate for poor technique. “If the operation is difficult, you are not doing it correctly.” —Robert Gross Always establish distal patency when operating for bowel atresia or stenosis. Sharp dissection and the use of “cutting” as opposed to “cautery” current cause less tissue trauma, which leads to better cosmetic results. Know how a congenital inguinal hernia differs from an adult inguinal hernia — and how the
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repair differs. Be able to list five reasons for surgical correction of an undescended testicle.
Chapter 58: Vascular Anomalies, Tumors, and Twins ● ● ● ● ● ● ● ● ●
Hemangiomas are true endothelial cell tumors, whereas vascular malformations represent errors in vascular development. In general, 50% of hemangiomas will resolve by age 5 years and up to 70% by age 7 years. Wilms' tumor is the most common renal tumor of childhood. Rhabdomyosarcoma is a soft tissue tumor that can arise just about anywhere; early biopsy is warranted, because stage at diagnosis is the most important prognostic factor. Thyroid nodules in children should undergo histologic evaluation, as 20% are malignant. Lymphatic malformations tend to infiltrate and surround important normal structures; proper knowledge of surgical anatomy will help to preserve these structures. When operating on a Wilms' tumor, explore the contralateral kidney for evidence of bilateral disease before proceeding to nephroureterectomy. Preoperative chemotherapy for neuroblastoma facilitates tumor excision, reduces postoperative complications, and improves patient survival. Benign and malignant ovarian teratomas are clinically indistinguishable and should be managed with an open technique.
Chapter 59: Surgical Techniques and Wound Management ●
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It is important to determine whether wound closure requires only an emergency room physician or whether the expertise of a plastic, general, or orthopedic surgeon is required. It is equally important to determine whether the wound closure can be carried out in the emergency room or the patient needs to go to the operating room. Open wounds are usually referred to as chronic if they have been present for more than 1 month. A wound is usually held together with sutures, staples, tape, or glue. A healing wound will contract in three dimensions, resulting in a shortening of the scar. Incisions should be placed inconspicuously so that neither the patient nor anyone else can see them. When this is not possible, they should be placed in the relaxed skin-tension lines, which are generally the same as wrinkle lines. When designing skin excisions, it is important to place the scar in or parallel to the relaxed skintension lines. It also is important to design the excision so that eversion of the skin edges is created. Wound débridement is usually carried out with a scalpel under local or general anesthesia. All necrotic tissue is removed, and, in addition, tissue that has questionable viability and is significantly contaminated should be removed. In general, all anatomic layers of wounds, such as muscle, fascia, dermis, and epidermis, should be closed. Subcutaneous fat has minimal holding strength, and sutures are usually not placed in this layer. In skin wounds, the dermal closure contributes most of the strength.
Chapter 60: Reconstructive and Aesthetic Breast Surgery ● ●
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Macromastia results from an increased sensitivity to hormonal stimulation of breast tissue that may be hereditary, because women with large breasts often have a family history. Macromastia may appear during menarche, or it may be the result of pregnancy, with failure of the breasts to reduce in size substantially after delivery and nursing. Macromastia is often caused by obesity, in which case, the majority of the breast is made up of adipose rather than glandular tissue. The goal with breast-reduction procedures is to reduce the size of the breasts and at the same time to maintain circulation and sensation to the nipple and possibly also some lactating function. Most studies of breast-reduction procedures show patient satisfaction rates between 95% and 98%. Dissatisfaction is usually associated with scarring.
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For small- to medium-size breast reductions, many plastic surgeons prefer to use a “vertical” technique, which limits the medial and lateral scars. For reduction of extremely large breasts with a preoperative suprasternal notch-to-nipple distance of at least 40 cm, a nipple-grafting technique is commonly used, which reduces the risk of tissue necrosis or infection. The breast implants that are currently used have a shell of a silicone elastomer and contain normal saline. In most patients, a submuscular implant is preferred. A submammary, peripheral transareolar or axillary incision can be used. With saline-containing implants, it must be only approximately 2.5 cm long.
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Chapter 61: Anatomy and Oncology The left renal vein has three branches (gonadal, lumbar, adrenal); the right has none.
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· A radical orchiectomy is performed through an inguinal incision to avoid violating the lymphatic drainage of the scrotum. · disease.
Unilateral hydronephrosis in the face of bladder cancer implies muscle-invasive
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Santorini's plexus is a network of veins on the dorsum of the prostate.
· The neurovascular bundles sit next to the prostate at the 5 and 7 o'clock positions. They provide important input in the initiation and maintenance of an erection. · Normal prostate specific antigen is defined as less than 4 ng/mL, but the definition of normal can vary according to age. ·
The peripheral zone of the prostate is responsible for most prostate cancer.
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The most common cause of bladder cancer is smoking.
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Bladder cancer most often is first seen as gross, painless hematuria.
· Only 10% of patients initially have the classic triad of renal cell cancer (flank pain, abdominal mass, hematuria). · Urge incontinence caused by bladder obstruction may not resolve after surgery to relieve the blockage in up to 25% of patients.
Chapter 62: Urinary Tract Dysfunction · Post-transurethral resection syndrome manifests as MS changes/seizures, bradycardia, and hypotension. It is caused by hyponatremia due to the absorption of irrigation fluids. · The distal limit of resection during a transurethral prostatectomy is the verumontanum, which estimates the position of the voluntary urethral sphincter. · Brisk hemorrhage during a sling operation is usually caused by injury to the perivesical venous plexus. ·
The potential space between the bladder and the pubis is called the space of Retzius.
· Sling operations have the highest-rated long-term success for the treatment of stress urinary incontinence. · The size of a man's prostate is not a good predictor of the amount of urinary symptoms that he may have. ·
Benign prostatic enlargement and stress urinary incontinence are diseases of “patient preference”
(i.e., the severity of bother usually determines the level of management). · Strong indications for a transurethral prostatectomy include gross hematuria, recurrent urinary tract infections, urinary retention,renal insufficiency due to bladder dysfunction, and bladder stones (GRRRS). · Urge incontinence caused by bladder obstruction may not resolve after surgery to relieve the blockage in up to 25% of patients.
Chapter 63: Urinary Tract Lithiasis and Infections ·
The most common type of urinary stone is composed of calcium oxalate.
· Urinary calculi are most likely to cause obstruction at the ureteropelvic junction, the pelvic brim, or the ureterovesical junction. · Extracorporeal shock wave lithotripsy is contraindicated in the face of active infection, coagulopathy, and pregnancy. ·
The holmium laser has a depth of penetration of 0.5 to 1.0 mm.
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Percutaneous kidney stone surgery is usually reserved for stones larger than 2 cm.
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Only uric acid calculi can be dissolved with oral medication (creating urinary alkalinization).
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Of urinary stones, 90% are radiopaque.
· The risk of kidney stone recurrence can be reduced by striving to produce 2 L of urine per day and maintaining a low-salt and low-animal-protein diet. ·
Acute bacterial infection makes up a small component of all men diagnosed with “prostatitis.”
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Roughly 50% of patients will have a repeated stone episode within the next 10 years.
Chapter 64: Anesthesia Special problems in patients with morbid obesity Obstructive sleep apnea Difficult intravenous access Rapid desaturation during intubation Risk of aspiration Difficult oxygenation/ventilation Difficult intubation Risk of positioning/nerve injury Multiple comorbidities Specialized postoperative monitoring Injury to staff
Chapter 65: Dermatologic Surgery · Skin cancer is the most common cancer in America. Annualized, more than one person an hour dies of skin cancer in the United States each year. · More skin cancers are diagnosed in the United States each year than all other cancers of all anatomic sites combined · Of patients diagnosed with a skin cancer, in 40%, a second, unrelated skin cancer will develop within the next 5 years. · Mohs surgery is the treatment of choice for nonmelanoma skin cancers in cosmetically sensitive areas, for which other therapies (e.g., standard excision) have failed, that have aggressive histologies (e.g., morpheaform), or that have a high risk of metastasis. · The ABCDs of melanoma stand for asymmetry, border irregularity, changing color or two or more colors, and large or changing diameter. · Ester anesthetics should not be used in patients with allergies to PAST: paraaminobenzoic acid, sulfur drugs, and thiazide diuretics. ·
Amide anesthetics (bupivacaine, mepivacaine) have an “i” before “-caine.”
· Concave areas (such as alar groove, medial canthus) heal well by secondary intention. The scalp, which is convex, also heals well by secondary intention and is the exception to this rule. · Before infiltrating the surgical area with anesthesia, mark out the skin-tension lines and cosmetic units of the face.
· When injecting local anesthesia, direct the needle into areas that are already anesthetized, and then advance the needle in the subcutis to the area that must be anesthetized. · When suturing on a scalp with dark brown/black hair, use polypropylene (Prolene) suture, which is blue, rather than nylon sutures, and leave long tails. This will make it easier to find and remove the stitches on the day of suture removal. · When suturing a flap in place, do not put many deep stitches at the tip of the flap. This can strangulate this critical area of the flap and lead to tip necrosis. · When sewing a graft/flap in a difficult-to-reach location (e.g., conchal bowl), consider using dissolvable sutures to spare the patient and staff from trying to remove the sutures later on. · An elliptical excision should have a 3:1 ratio of the long axis to the short axis and apex angles of 30 degrees. ·
Tension on the wound edges is the number one killer of flaps (flap necrosis).
Chapter 66: Minimal Access Surgery · In comparison with open surgery, laparoscopic surgery is usually associated with smaller incisions, shorter hospitalizations, less postoperative pain, faster recuperation, and decreased costs. · Diagnostic laparoscopy is especially useful for the evaluation of abdominal pain in women of childbearing age or in patients whose diagnosis is unclear. · Laparoscopic techniques have reduced the threshold for surgical referral for several common diseases, including symptomatic cholelithiasis and gastroesophageal reflux disease. · gallbladder.
Laparoscopic cholecystectomy is now the gold standard for removing a diseased
· Laparoscopic inguinal herniorrhaphy may be performed transabdominally or completely extraperitoneally. · Contraindications to laparoscopic abdominal procedures include advanced generalized peritonitis, hypovolemic shock, massive abdominal distention with clinical evidence of bowel obstruction, uncorrected coagulopathy, and inability of the patient to tolerate a formal laparotomy. · The CO 2 pneumoperitoneum may cause hypercapnia, acidosis, and cardiac arrhythmias, especially in patients with cardiopulmonary diseases. · patients.
Alternatives to the CO 2 pneumoperitoneum should be considered in high-risk
· Improper trocar placement during laparoscopic surgery can result in major vascular injury, intestinal injury, or air embolism. ·
Before laparoscopy is begun, all electronic equipment should be checked.
· Before a Veress needle is inserted, it should be examined to ensure that the spring mechanism is intact and that the lumen flushes easily. · The risk of blood vessel, bowel, and bladder injuries is lower with open trocar insertion than with closed trocar insertion. · The locations for trocar placement depend on the procedure being performed. The appropriate location for a secondary port can be verified by sounding it out with a Veress needle.
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All secondary trocars should be placed under direct laparoscopic vision.
· Extracorporeal knot-tying techniques are useful on tissue that will tolerate extra suture material being drawn through it. · To avoid tissue tearing during extracorporeal knot tying, the knot pusher should be treated as an extension of the surgeon's finger. ·
Intracorporeal knot-tying techniques are appropriate for delicate tissues.
· During intracorporeal suturing, the suture tail should be kept short and next to the knot to facilitate knot tying.
Chapter 67: Transplant · The most common technical complication associated with kidney transplantation is lymphocele. (A collection of lymphatic fluid surrounding the graft may cause renal compression, hydronephrosis, and elevated creatinine levels.) · Cytomegalovirus infection after a transplant usually causes fever and malaise and commonly occurs approximately 6 weeks after transplant. It also may be associated with tissue-invasive disease, such as gastroenteritis or hepatitis. · Spontaneous bacterial peritonitis occurs in patients with chronic liver disease, is the result of severe protein-synthesis dysfunction, and indicates an inability to opsonize bacteria. Of these patients, 50% die within 6 months of this diagnosis if not given a transplant. · A replaced hepatic artery refers to a branch that usually arises from the proximal 2 cm of the superior mesenteric artery. It travels posterolateral to the portal vein, supplying the right lobe. It is present in 15% of people. · The ureter of the renal allograft is usually cut short before anastomosis to the bladder because the blood supply to the upper two thirds of the ureter arises from the renal artery, and the lower third is supplied by arterial branches from the bladder. Thus only the proximal ureter has reliable arterialization after transplant. · The pancreas has a dual blood supply. The head of the pancreas receives blood via gastroduodenal and inferior pancreaticoduodenal arteries, whereas the body and tail depend on branches of the splenic artery.
