Intestinal Anastomosis

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ACS Surgery: Principles and Practice 29 Intestinal Anastomosis — 1

INTESTINAL ANAST ANASTOMOSIS OMOSIS

Julian Britton, M .S ., ., F.R.C.S.

Intestinal obstruction, obstruction, peritonitis from a perforated bowel, bowel, abdominal trauma, and disease of the bowel are common surgical problems problems throughout the world. world. These problems usually must be treated operatively operat ively;; hence, it is frequently necessary necessary to join two sections sections of bowel bow el together. together. Unlike joining joining two areas of skin, where there there is a powerful pow erful evolutionary evolutionary incentive to achieve rapid healing, healing, joining two segments of bowel so as to restore intestinal function without leakage of intestinal intestinal contents is not easy. easy. Over time, the basic principles crucial for obtaining successful results have been defined [see Table 1]. Accurate approximation of the bowel without tension and with a good blood supply to both of the structures being joined are obviously obviously fundamental. fundamental. Surgical technique technique is equally importan imp ortant: t: bet betwee ween n two given given surgeons, surgeons, rat rates es of anastom anastomotic otic breakdown can vary by as much as a factor of 60. 1 Failure of an anastomosis with leakage of intestinal contents is still, regrettab regrettably, ly, a common common surgical experience. Reported failure rates range from 1.5%2 to 2.2%,3 depending on what type of anastomosis was performed and whether the operation was an elective or an emergency procedure. A leaking anastomosis greatly increases the morbidity morbidity and mortality associated associated with the operation: operation: it can double the length of the hospital stay and increase the mortality as much as 10-fold.4 Deh Dehisce iscence, nce, whe when n it occurs, has been been associated with one fifth to one third of all postoperative deaths in patients who underwent an intestinal anastomosis. 5 Unfortunately, anastomotic dehiscence dehiscence can occur even even in ideal circumstances.This unwelcome fact has stimulated a great deal of debate regarding the reliability of various methods and approaches. With the aim of clarifying the debate, I will address certain fundamental technical issues in the performance of an intestinal anastomosis and attempt to summarize what is known about how these issues relate to the reliability of the various anastomotic techniques in current use. I will then outline operative operative approaches approaches to performing three common intestinal anastomoses in somewhat greater detail d etail [se [seee Operative Techniques for Selected Selec ted Anastomoses, below ]. below]. Intestinal Anastomotic Healing

Most of the strength of the bowel wall resides in the submucosa6; how howeve ever, r, for the the purpos purpose e of suturin suturing g bowel bowel segmen segments ts together, togeth er, it is important to keep keep in mind that that the serosa (i.e., (i.e., the visceral peritoneum) holds sutures better than either the longitu1]. The absence dinal or the circular muscle layer [see [see Figure 1]. absence of a peritoneal layer makes suturing of the thoracic esophagus and the rectum below the peritoneal reflection technically more difficult than suturing suturing the intraperitoneal intraperitoneal segments segments of the the intestine. intestine. In addition,, the stomach and the small bowel addition bowel possess a richer blood supply than the esophagus and the large bowel and consequently tend to heal more readily. The process of intestinal anastomotic healing mimics that of wound healing elsewhere in the body in that it can be arbitrarily

divided into an acute acute inflammatory inflammatory (lag) phase, a proliferative proliferative phas ph ase, e, an and, d, fin final ally ly,, a remod remodel elin ing g or matu matura rati tion on phas phase. e. Th The e strongest component of the bowel bowel wall, the submucosa, owes most of its strength to the collagenous connective tissue it contains. Collagen is thus the single most important molecule for determining intestinal intestinal strength, which makes its metabolism metabolism of particular interest for understanding anastomotic healing. Collagen is secreted from fibroblasts in a monomeric form called tropocollagen; this is a large, stiff molecule that that can be visualized visualized by electron microscopy. microscopy. Collagen itself can be be divided into subtypes on the basis of compositional differences (i.e., different combinachains).T Type I collagen predominates in mature tions of α1 and α2 chains). organisms; organi sms; type II is found found primarily primarily in cartilage; cartilage; and type type III is associated with type I in remodeling tissue and in elastic tissues such as the the aorta, the esophag esophagus, us, and the uterus. uterus. Synth Synthesis esis of collagen is an intracellular process that that occurs on polysomes. A critical stage in collagen formation is the hydroxylation of proline to produce hydroxyproline;this hydroxyproline; this process is believed believed to be important for maintaining the three-dimensional triple-helix conformation of mature collagen, which gives the the molecule its structural strength. strength. The amount of collagen found in a tissue is indirectly determined by measuring the amount of hydroxyproline, though no significant statistical correlation between hydroxyproline content and objective measurements of anastomotic strength has ever been demonstrated.7 Vitamin C deficiency results in impaired hydroxylation of proline and the accumulation accumulation of proline-rich, hydroxyproline-poor molecules in intracellular vacuoles. The degree of fiber and fibril cross-linking relates to the maturity of the collagen and is probably important in determining the overall over all strength of the scar tissue. Of equal importance is the orientation of the fibers and their weave. weave. The bursting pressure of anastomoses has often been used to gauge the strength of the healing process.This pressure has been found to increase rapidly in the early postoperati postoperative ve period, reaching 60% of the strength strength of the surrounding bowel by 3 to 4 days and 100% by 1 week. 8,9 Collagen synthesis is a dynamic process that depends on the balance betwe between en synthesis synthesis and collagenolysis collagenolysis.. Degradat Degradation ion of mature collagen begins in the first 24 hours and predominates for

Principles Table 1— 1— Principles

of Successful Intestinal Anastomosis

Well-nourished patient with no systemic illness No fecal contamination, either within the gut or in the surrounding peritoneal cavity Adequate exposure and access Well-vascularized tissues Absence of tension at the anastomosis Meticulous technique

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I ntes ntesti ti nal An astom os osis is — 2

Serosa (Visceral Peritoneum)

Longitudinal Muscle Layer

Circular Muscle Layer Submucosa Mucosa

Figure 1 Shown are the tissue layers of the jejunum. Most of the bowel wall’s strength is provided by the submucosa.

the first 4 days. By 1 week, week, collagen synthes synthesis is is the the dominant force, particularl particularly y proximal to the anastomosis. anastomosis.After After 5 to 6 weeks weeks,, there is no significant increase in the amount of collagen in a healing wound or anastomosis, though turnover and thus synthesis are extensive.The strength of the scar continues to increase for many months after injur injury y. Local infection increases collagenase activity and reduces levels of circulating collagenase inhibitors.10,11 Collagen synthetic capacity is relatively uniform unifor m throughout the large bowel bowel but less so in the small intestine: synthe synthesis sis is significantly higher in the proximal and distal small intestine than in the midjejunum. Overall collagen synthetic capacity is somewhat less in the small intestine. Although no significant difference has been found between the strength of ileal anastomoses and that of colonic anastomos anastomoses es at 4 days, days, colonic collagen collagen formation formation is much greater in the first 48 hours.12 It is noteworthy that the synthetic response is not restricted to the anastomotic site but appears to be generalized to a significant extent. 13 Various attempts have been made to improve the healing of intestinal anastomoses. anastomoses. A 2002 animal study concluded that locally applied charged particles improved the healing of colonic anastomoses.14 Technical Options for Fashioning Anastomoses

Sewing bowel segments together with various suture materials, ranging from catgut to stainless steel wire, has been a standard surgical technique technique for more than 150 years. Staple Staplers, rs, though first developed early in the 20th century, only began to have a significant impact on GI surgery within the past three decades. Staplers certainly

appeal to the technically minded, and most studies suggest that they however ever,, they remain remain relasave a small amount of operating time15; how tively expensive, and it is still unclear whether the the results are any better than can be achieved with suturing. suturing. Accordingly Accordingly,, it is worthwhile to examine the technical aspects of the two approaches to bowel anastomosis and to compare their respective merits. SUTURING:TECHNICAL ISSUES

Choice of Suture Material Sutures act as foreign bodies in the anastomosis and thus produce an inflammatory reaction.7 One study that examined the relative efficiency of absorbable and nonabsorbable material concluded that the strength of the the anastomosis, expressed as a percentage of normal tissue strength, was essentially the same regardless of the type of suture used. Other studies that examined the the amount of inflammation induced at the anastomosis by various types of sutures found that polypropyle polypropylene ne (Prolene), catgu catgut, t, and polyglycolic polyglycolic acid 16,17 (Dexon) were equivalent in this regard. Silk,, how Silk howeve ever, r, prod produced uced a significantly greater cellular reaction at the anastomosis, and the reaction persisted for as long as 6 weeks.17 A 1975 study reported on a series of 41 patients who underwent low anterior resection involving a primary side-to-end colorectal anastomosis with 5-0 stainless steel wire.18 The investigators considered this material ideal because of its strength and relative relative inertness within the tissues, and they supported their claims with a relatively low clinical leakage rate (7.3%). The ideal suture material—one that causes minimal inflammation and tissue reaction while providing maximum strength during the lag phase of wound healing—is yet to be discovered.


ACS Surgery: Principles and and Practice Practice

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a

29 I ntes ntesti ti nal Anastomosis Anastomosis — 3

similar construction, construction, consistin consisting g of an inner layer of continuous or interrupted absorbable sutures and an outer layer of interrupted 3]. Traditiona absorbable or nonabsorbable sutures [see [see Figure 3]. raditionally, lly, double-layer anastomoses have been considered more secure; however, how ever, for some time, single-l single-layer ayer anastomoses anastomoses have have been performed in difficult locations locations (e.g., low in the pelvis or high in the chest) or in difficult circumstances (e.g., in a patient who is unstable or has multiple intra-abdominal injuries) with good results. Moreover, work from the 1980s suggests that the single-layer technique has significant inherent advantages.23-26 Double-layer anastomoses were long believed to be essential for safe healing; how however, ever, subseq subsequent uent path pathologic ologic analysis of these these anastomoses revealed microscopic areas of necrosis and sloughing of the tissues incorporated in the inner layer as a result of strangulation.27 Animal studies confirmed that single-layer anastomoses take less time to create, 28 cause less narrowing of the intestinal lumen,24-29 foster more rapid vascularization23 and mucosal healing, and increase the strength strength of the anastomosis (as measured measured by the bursting pressure) in the first few postoperative days. 28 Nonetheless, Noneth eless, althoug although h clinical studies studies have have fairly consistently consistently demonstrated that single-layer anastomoses are associated with

b

a

b

c

d

c

Figure 2 Shown are stitches commonly used in fashioning intestinal intes tinal anastomoses: anastomoses: (a) the continuous over-and-over suture, (b) the interrupted interrupted Lembert suture, suture, and (c (c) the Connell suture.

Clearly, how Clearly, however, ever, monofilam monofilament ent and coated coated braided sutures sutures represent an advance beyond silk and other multifilament materials. Continuouss versus Interr upted Sutures Continuou Both continuous and interrupted sutures are commonly used in fashioning intestinal anastomoses [see [see Figure 2]. randomiz omized ed 2]. No rand trials have addressed the question of whether interrupted sutures have a significant advantage over continuous sutures in a singlelayer lay er anastom anastomosis osis;; how howeve ever, r, retr retrosp ospecti ective ve reviews reviews hav have e not revealed any such advantage.19-21 Animal studies, on the the other other hand, indicat indicated ed that perianastomotic perianastomotic tissue oxygen oxygen tension was significantly less with continuous sutures than with interrupted sutures.22 This finding was correlated with an increased anastomotic complication rate and impaired collagen synthesis and healing with continuous sutures in a rat model.23 Single-Layer versus Double-Layer Anastomoses Double-layer anastomoses were described in the literature before single-layer single-layer ones. All such anastomoses anastomoses are of essentia essentially lly

anastomosis. (a) Interrupted Figure 3 Double-layer end-to-end anastomosis. Lembert stitches are used to form form the posterior outer layer. layer. (b) A full-thickness continuous over-and-over stitch is used to form the posterior posteri or inner layer. layer. (c) A Connell stitch is used to form the anterior anterio r inner layer. layer. (d ) Interrupted Lembert stitches are used to form the anterior outer layer.




improved postoperative return to normal bowel function (as measured sure d by bowe bowell sounds, sounds, pas passage sage of of flatus, flatus, and return return to oral oral intake),30,31 nonrandomized studies of anastomotic leakage rates have not shown any differences between single- and double-layer anastomoses in this regard.32-34 Some authors still favor double-layer anastomoses when the tissues are very very edematous or friable, are under minimal minimal tension, tension, or lie in highly vascular vascular areas (e.g., the stomach). stomach). There are no data to indicate that this practice yields superior results. STAPLING:TECHNICAL ST APLING:TECHNICAL ISSUES

Choice of Stapler Surgical stapling devices were first introduced in 1908 by Hültl; however, they did not gain popularity at that time and and for some time afterward because the early instruments were cumbersome and unreliable. unreliable. The develop development ment of of reliable, reliable, disposab disposable le instruinstruments over the past 25 years has changed surgical practice dra-

29 I nt esti nal Anastomosis Anastomosis — 4

matically.. With modern devices, technica matically technicall failures failures are rarer, the staple lines are of more consistent quality, and anastomoses in difficult locations are easier to construct. Three different types of stapler are commonly used for fashioning intestinal anastomoses. The transverse anastomosis (TA) (TA) stapler is the simplest of these.This device places two staggered rows of B-shaped staples across the bowel but does not cut it: the bowel must then be divided in a separate step.The gastrointestinal anastomosis (GIA) stapler places two double staggered rows of staples and simultaneously cuts between between the double rows.The circular, or end-to-end anastomosis (EEA), stapler places a double row of staples in a circle and then cuts out the tissue within the circle of staples with a built-in cylindrical knife. All of these staplers are available in a range of lengths or diameters. Staple Staplers rs may be used to create functional or true anatomic end-to-end anastomoses as well as side-to-side side-to-side anastomoses. anastomoses. The original staplers were all designed for use in open procedures, procedures, but there are now a number number of instruments (mostly of the GIA type) available for use in laparo-

a

b

c

d

linear noncutting stapler. stapler. (a) The bowel bowel ends are triangulatFigure 4 End-to-end anastomosis with linear ed with three traction sutures. (b) A noncutting linear stapler (TA) is placed between two of the suture sut ures. s. (c) The stapler is closed and the excess tissue excised. (d ) The bowel is rotated, and steps b and c are repeated twice more to close the remaining two sides of the triangle.




scopic procedures. The staples themselves are all made of titanium, which causes little little tissue reaction.They are not magnetic and do not cause subsequent difficulties with MRI scanning. In a function functional al end-to-end anastomosis, anastomosis, two cut ends of bowel (either open or stapled closed) are placed side by side with their blind ends ends beside beside each other other.. If the bow bowel el ends are closed, closed, an enterotomy must be made in each loop of bowel to allow insertion of the stapler. stapler. A cutting linear (GIA) (GIA) stapler is then used to fuse the two bowel walls into a single septum with two double staggered rows of staples and to create cr eate a lumen between the two bowel segments by dividing this septum between the rows. A noncutting linear (TA) stapler is then used to close the defect at the apex of the anastomosis anastomosis where the GIA stapler was inserted. An alternative, and cheaper, method of closing closing the defect is to use a continuous suture. The cut and stapled edges of the bowel bowel should be inspected for adequacy of hemostasis before the apex is closed. Some authors suggest cauterizing these edges to ensure hemostasis35; how howeve ever, r, give given n that elect electrical rical current current may may be conducted conducted along the metallic staple line to the rest of the bowel, it is probably easier and safer simply to underpin bleeding vessels with a fine absorbable absorba ble suture. It is also important to offset the two inverted inverted staple lines before closing the apex.36 True anatomic end-to-end stapled anastomoses may be fashioned with a linear stapler by triangulating the two cut ends and then firing the stapler three times in intersecting vectors to achieve 4]. The potential complete closure [see [see Figure 4]. potential drawback drawback of this this approach is that the staple lines are all everted. It is often easier to join two cut ends of bowel bowel with an EEA stapler, which creates a directl dire ctly y apposed, apposed, inv inverted erted,, sta staple pled d end-to-en end-to-end d anastomos anastomosis. is. However, Howe ver, circular staplers staplers can be more difficult to use at times times because of the need to invert a complete circle of full-thickness bowel wall. In addition—at least at locations other than the anus— they typically require closure of an adjacent enterotomy. Staple Height TA and GIA staplers are available with a variety of inserts containing several different types of staples.These inserts vary with respect to width, width, the height (or depth) depth) of the closed staple,and staple, and the distance between the staples in the rows.They are designed for use in specific tissues, and it is important to choose the correct stapler insert for a given application. application.In In particular, inserts designed for closing closing blood vessels should not be used on the bowel, bowel, and vice versa.With TA and EEA staplers, it is possible to vary the depth of the the closed staples by altering the distance between the staples and the anvil as the instrument is closed.The safe range of closure is usually indicated by a colored or shaded area on the shaft of the instrument.Thus, if full closure would cause excessive crushing of the intervening tissues, the stapler need not be closed to its maximum extent. A 1987 comparison of anastomotic techniques that used blood flow to the divided tissues as a measure of outcome found that the best blood flow to the healing site was provided by stapled anastomoses in which the staple height was adjusted to the thickness of the bowel wall.37 The next best blood flow was provided by double-layer stapled and sutured anastomoses, followed by double-layer double-layer sutured anastomoses anastomos es and tightly stapled anastomoses, in that order. Single-Stapled versus Double-Stapled Anastomoses To accomplish many many of these anastomoses, intersecting staple lines are created. created. Initiall Initially, y, some concern was expressed expressed about about the security of these areas and about the ability of the blade in the cutting staplers staplers to divide a double staggered row of staples. staples. Animal studies, how however, ever, demonstra demonstrated ted that that even even though though nearly nearly all all (> 90%) of the staple lines that were subsequently transected by a


second staple line contained bent or cut staples, the integrity of the anastomosis anastom osis was not compromised compromised in any way, way, nor was healing adversely affected.38,39 HAND-SEWN VERSUS STAPLED ANASTOMOSES

Stapled anastomoses are said to heal by primary intention, whereas sutured anastomoses are said to heal by secondary intention, though further experimentation experimentation is needed to confirm this distinction.40 Titanium staples are ideal for tissue apposition at anastomotic sites because they provoke only a minimal inflammatory response and provide immediate strength to the cut surfaces during the weakest phase phase of healing. Initially Initially,, tissue eversion eversion at the stapled anastomosis anastomosis was a major concern, given that everted everted handsewn anastomoses had previously been shown to be inferior to inverted inve rted ones; how however, ever, the greater greater support and improv improved ed blood supply to the healing tissues associated with stapling tend to counteract the negative negative effects effects of eversion. In fact, one study found that bursting strength for canine colonic end-to-end anastomoses was six times greater when the procedure was performed with an EEA stapler than when it was done with interrupted Dacron sutures. 41 Another study demonstrated a significantly reduced radiographic anastomotic leakage rate with staples applied by an EEA stapler as opposed to a double layer of sutures.42 Various prospectiv prospective, e, randomized trials have demonstrated no differences in clinical and subclinical subclini cal leakage rates, length of hospital stay, stay, or overall morbid15,39,43-46 ity. Even when the anastomosis had to heal under adverse conditi cond itions ons (e.g., (e.g., carc carcinom inomato atosis, sis, mal malnutri nutritio tion, n, prev previous ious chemochemotherapy therap y or radiation radiation therapy, therapy, bow bowel el obstruction, obstruction, anemia, or leukopenia), no significant differences differences were apparent between between stapled and hand-sewn hand-sewn anastomoses. anastomoses. Stapli Stapling ng did, how however, ever, shorten operating time, especially for low low pelvic anastomoses. Cancer recurrence recur rence rates at the site of the anastomosis have been reported to be higher or lower depending on the technique used. Certainly,, suture materials Certainly materials engender a more pronounce pronounced d cellular proliferative prolifera tive response response than titanium staples do, particularl particularly y with full-thickness sutures as opposed to seromuscular ones,47 and malignant cells have been shown to adhere to suture materials.48 Two studies suggested that stapling anastomoses after resection for cancer reduces anastomotic recurrence by 40% and cancerspecific mortality by 50%. 47,49 UNUSUAL TECHNIQUES

In 1892, Murph Murphy y introduced introduced his button button,, whic which h consisted consisted of a two-part metal stud that was designed to hold the bowel edges in apposition without suturing until adhesion had occurred.50 Thereafter, the stud was voided voided via the the rectum. Several modifications modifications of this technique have have been described since then, primarily focusing on the composition composition of the rings or stents. In particular, dissolvab dissolvable le polyglycolic acid systems have been developed.These so-called biofragmentable anastomotic anastomotic rings leave leave a gap of 1.5, 2.0, or 2.5 mm between the bowel ends to prevent ischemia of the anastomotic line. The use of adhesive agents such as methyl-2-cyanoacrylate to approximate the divided ends of intestinal segments has been studied as well.51 There was only a moderate inflammatory response at the wound, which persisted for 2 to 3 weeks. weeks. Leakage rates were high, however, how ever,and and many technical problems problems remained (e.g., how to stabilize the bowel edges while they underwent adhesion). Fibrin glues have also been employed in this setting. Although these substances are not strong enough to hold two pieces of bowel in apposition, they have been used to coat a sutured bowel anastomosis in an effort to reduce the risk of anastomotic failure. So far, no controlled clinical clinical trials have have confirmed that that this approach is worthwhile.

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Factors Contributing to Failure of Anastomoses

ACS Surgery: Principles and Practice 29 I nt esti nal Anastom Anastom os osis is — 6

Thromboembolism] is mandatory in all patients scheduled to Thromboembolism] undergo intestinal anastomosis.

TYPE AND LOCATION OF ANASTOMOSIS

As a rule, for any given technique, technique, the location location of the the anastoanastomosis seems not to influence the overall leakage rate. There are two exceptions exceptions to this this general rule. First, low anterior anterior rectal anastomoses are associated with leakage rates ranging from 4.5% to an incredible 70%.52,53 Second, esopha esophageal geal anastomoses are associa associatt54 ed with leakage rates of about 5%. Animal studies demonstrated improved transmission of the intestinal migrating myoelectric complex across hand-sewn endto-end anastomoses, anastomoses, compare compared d with stapled or sewn side-to-side side-to-side or end-to-side anastomoses or stapled functional end-to-end anastomoses.55 This improvement may be significant for patients with diseases affecting affecting small bowel bowel motility motility,, but in ordinary surgical practice, there is no difference between the the two methods methods of anastomosis with respect to return of intestinal function. 56 PATIENT PREPARATION

Many intestinal anastomoses are constructed in an emergency setting. sett ing. In this context, carefu carefull preoperativ preoperative e preparation, preparation, includi including ng adequate fluid resuscitation, resuscitation, is important and should be carried out to the extent possible. Elective patients patients should be as fit as is feasible, and any other active coexisting illnesses should be stabilized or controlled as well as possible.To possible.To maximize the chances that the anastomosis will heal uneventfully, uneventfully, patients should be well well nourished and not anemic. Adequate preoperative preoperative antibiotic prophylaxis has been shown to reduce the risk of postoperative infection in all types of bowel surgery and must be given at the start of the operation [see [ see 1:6 Postoperativee Pain ]. Some patients require additional steroids Postoperativ :10 Problems]. perioperatively [see [see 8:1 0 Endocrine Problems]. For elective operations on the colon, it is traditional to empty the bowel bow el before surgery. surgery. Some studies, studies, how however ever,, hav have e suggested suggested that mechanical bowel preparation may not be essential for successful healing.57,58 In one such study,a study, a series of 72 patients underwent elective colonic anastomosis without any mechanical bowel preparation and with a single preoperative dose of I.V. antibiotics. 57 Anastomotic dehiscence was not observed, nor were any differences in wound infection rates (8.3%) or overall mortality (2.7%) noted in comparison with published reports of series of patients who underwent full bowel preparation. preparation. On the other hand,a hand, a 1989 study reported significantsignificantly increased anastomotic bursting pressure and reduced anastomotic dehiscence rates in dogs that underwent mechanical bowel cleansing before low anterior resection.52 This observation was further supported by a study showing that adding oral erythromycin and kanamycin to bowel preparation led to significantly increased bursting pressure at 7 days after operation. 59 In a number of published clinical series, inadequate bowel bowel preparation increased the incidence of anastomotic complications.53,60 How However ever,, there are also several papers in which mechanical bowel preparation yielded no demonstrable demonstrab le benefit.61 Whatever the advantages or disadvantages of preoperative bowel preparation from a postoperative point of view, view, most surgeons would agree that it is much easier to operate on an empty bowel. bow el. Severa Severall methods of bowel preparation preparation are in current use, including oral laxatives (e.g., magnesium sulfate and sodium picosulfate) sulfa te),, enem enemas, as, was washou houts, ts, and various various combinati combinations ons of the these. se. It is advisable for patients to stop eating solid food 24 hours before the operation. The evidence that adding oral antibiotics is beneficial is inconclusive, but many trials have confirmed the benefits of one, two two,, or three doses doses of I.V. antibio antibiotics tics over over the perioperat perioperative ive period. Prophylaxis of thromboembolism [see [ see 6 :6 Venous

ASSOCIATED DISEASES AND SYSTEMIC FACTORS

Anemia, diabetes mellitus, mellitus, previous irradiation or chemotherapy chemotherapy,, malnutrition with hypoalbuminemi hypoalbuminemia, a, and vitamin deficiencies are all associated associat ed with poor anastomotic healing. Some of these factors can be corrected preoperatively preoperatively. Malnourished patients patients benefit from nutritional support delivered enterally or parenterally before and after :22 r ]t .W operation [see [see 8:2 .Well-n ell-nourishe ourished d patients patients apap2 Nutritional Suppo pear not to derive der ive similar benefits from such support.62 Resections for Crohn disease appear to carry a significant risk of anastomotic dehiscence (12% in one on e prospective study) even when macroscopically normal margins are obtained.3 Strictureplasty has therefore become an attractive alternative to resectional management of Crohn disease even in the presence of moderately long strictures, diseased tissue, tissue, or sites of previous previous anastomoses. anastomoses. The glucocorticoid response to injury may attenuate physiologic responses to other mediators whose combined effects could be deleterious to the organism.63 In animal experiments, experiments, wound healing, as measured by bursting bursting pressure of an ileal anastomosis anastomosis 1 week after operation, was optimal at at a plasma plasma corticosterone level that maintained maximal nitrogen balance and corresponded to the mean corticosterone level of normal animals.64 Both supranormal and subnormal cortisol levels resulted in significantly impaired wound healing, probably through different mechanisms. It is believed that slow protein turnover is responsible for delayed anastomotic healing in adrenalectomized animals,65 whereas negative nitrogen metabolic balance is responsible for increased protein breakdown and delayed healing in animals with excess glucocorticoid activity.64 Nonsteroidal anti-inflammatory drugs (NSAIDs) may help increase anastomotic bursting pressure by decreasing perianastomotic inflammation,66,67 but this effect has not been well studied. studied. Controversiall Issues in Intestinal Anastomosis Controversia INVERSION VERSUS EVERSION

The question of the importance of inversion (as described by Lembert in the early 1800s) versus eversion of the anastomotic line has long been a controversial one. It has been argued that the traditional inverting methods ignore the basic principle of accurately opposing opposing clean-cut tissues. tissues. In the late 19th century, Halsted proposed propose d an interrupted extramucosal extramucosal technique, technique, which has since been assessed in retrospective1 and prospective3 reviews and found to have a low leakage rate (1.3% to 6.0%) in a wide variety of circumstances. A 1969 study reported greater anastomotic strength, less luminal narrowing, narrowing, and less edema and inflammat inflammation ion with everted small intestinal anastomoses in dogs.67 Subsequent laboratory and clinical studies have not confirmed these findings and, in fact, hav have e often yielded quite quite the opposite opposite results: lowe lowerr bursting pressure,68 slower healing,69 and more severe inflammation31 have all been been associated with an everted everted suture line. Another argument in favor of inversion inversion is an aesthetic one: an inverted anastoanastomosis always looks neater. NASOGASTRIC DECOMPRESSION

Routine nasogastric decompression in patients undergoing a procedure involving an intestinal anastomosis remains controverrandomiz omized, ed, cont controll rolled ed sial. In retrospe retrospective ctive70 and prospective,71 rand trials, routine use of a nasogastric nasogastric tube conferred conferred no significant advantage. advant age. In fact, there was was a trend trend toward toward an increased increased inciinci-




dence of respiratory tract infections after routine gastric decompression.72 Nonethe Nonetheless, less, one study study found that that nearly nearly 20% of patients required insertion of a gastric tube in the early postoperative period.71 If the choice is made not to place a nasogastric tube routinely,, it is important to remain alert to the potential routinely potential for gastric dilatation, which can develop suddenly and without warning. ABDOMINAL DRAINS

There has been a great deal of disagreement regarding the ability of abdomin abdominal al drainage drainage to “prot “protect ect” ” an anastom anastomosis osis.. Eve Even n before World War I, the old dictum dictum “when “when in doubt, drain” was called into question by Yates, who wrote that the peritoneal cavity could not be effectively drained because of adhesions and rapid sealing of the drain tract.73 Six decades later, later, one study showed showed a dramatic increase in the incidence of anastomotic dehiscence (from 15% to 55%) after the placement of perianastomotic drains in dogs.74 This increase was associated with a significant increase in mortality. A 1999 study of pelvic drainage after a rectal or anal anastomosis showed that prophylactic drainage did not improve outcome or reduce complications.75Yet another study reported the severe inflammatory reaction caused by drains at anastomoses.76 These findings to the contrary, many surgeons elect to place an intra-abdominal drain to the pelvis after an anterior resection or a coloanal anastomosis because of the higher than usual risk that a fluid collection will develop. develop. Drainage is rarely helpful, helpful, or indeed easy, easy, after a gastric or small bowel bowel anastomosis. Drains are indicated, however,after ever, after emergency operations operations for peritonitis or trauma in which it was necessary to close or anastomose damaged or inflamed bowel. Rectal tubes are commonly employed after subtotal colectomy for acute colitis and after two-stage pelvic pouch procedures. Operative Techniques for Selected Anastomoses

In what follows, follows, I outline the essential preliminary preliminary steps before a bowel anastomosis and then describe three generic operations involving the small and large bowel. bowel. These procedures illustrate many of the general principles previously discussed (see above). PATIENT POSITIONING AND INCISION

Patients must be positioned on the operating table in a manner that is appropriate appropriate for the planned operation. operation. Most abdominal abdominal operations are performed through a midline incision of adequate length with with the patient patient supine. For pelvic procedures, procedures, the patient patient is placed in the lithotomy position to allow access to the abdomen and the anus; care must be taken taken to position the the legs and feet in the stirrups correctly, correctly, witho without ut excessive flexion or abduction and with sufficient padding to prevent pressure ulceration, thrombosis, and neurapraxia. neurapraxia. For esophageal esophageal procedures, procedures, the patient patient is posipositioned lying on the appropriate appropriate side, and the incision of choice is 4:7 Open Open Esophageal Procedures]. Procedures]. Occaa lateral thoracotomy [see [see 4:7 sionally,, the patient sionally patient must be shifted to a different position during the course of an operation. Gravity can be useful for moving structures out of the way. Accordingly, According ly, it is often helpful to alter alter the axis of the operating operating table. For example example,, a 30° head down or Trendelenb rendelenburg urg position position facilitates pelvic operations. EXPOSURE,, MOBILIZA EXPOSURE MOBILIZATION, TION, AND DISSECTION

The incision should should be held open with a suitable retractor. retractor. In addition,, sophis addition sophisticate ticated d mechanical mechanical systems are available available that that attach to the operating table and can be positioned to expose the area of the surgeon’s attention, thereby reducing the need for surgical assistants. assistants. Constructi Constructing ng such systems and adjusting them for


specific patients patients takes takes some time and skill, but the effort is usually well rewarded. rewarded. Adequa Adequate te exposure of the operative operative field is an essential essenti al preliminary to any operat operation. ion. Given that most intestinal intestinal operations operat ions are performed inside the body cavity cavity,, packing away away structures that are not required for the procedure being done is an important skill. skill. In a pelvic operation, operation, for example, example, the small bowel bowel should be packed into the upper abdomen and retained there with a suitable retractor; retractor; in an esophageal esophageal resection, the lung should be deflated and held well away. In the absence of adhesions or tethering caused by disease, disease, the small bowel is usually sufficiently mobile to allow the relevant segment to be brought out of the abdomen. Doing so makes the operation easier and allows the remainder of the bowel to be kept warm and tension free inside the the abdominal abdominal cavity. Somet Sometimes, imes, the transverse transverse colon and the sigmoid colon are mobile enough to be brought to the surface. More commonly, commonly, howev however, er, as with the other sections of the large bowel, bowel, the peritoneum must be divided along the lateral border of the colon and the retroperitoneal structures reflected posteriorly.Tension is rarely a problem during small bowel anastomosis, but for colonic or esophageal anastomoses, anastomoses, it is absolutely vital that that the two ends of bowel to be joined lie together easily. easily. For a large bowel anastomosis, anastomosis, this means that the splenic splenic flexure or the hepatic flexure—or, sometimes, both—must be adequately mobilized. Classically,, the tissues around the bowel are divided with a scisClassically sors, whereas the mesentery is divided between between clamps and tied with a suitable suitable thread. Recognized tissue planes are separated by by means of blunt dissection with with either the fingers or a swab swab.. Minor bleeding points are occluded with a coagulating electrocautery, though this approach is often relatively ineffective on mesenteric or omental vessels.The disadvantages of this dissection technique are that oozing from raw surfaces can be a nuisance and that the tissues beyond a tie are often bulky and leave dead tissue within the body that may may act as a focus for infection and adhesions. Newer methods of dissection that make use of the ultrasonic scalpel or the bloodless bipolar electrocautery prevent these problems by coagulating a small section of tissue between the jaws of the instrument and simultaneously occluding all blood vessels up to a certain size within the tissues. tissues. Consequently, bleeding is reduced, fewer (or no) ties are needed, and only a small quantity quantity of dead tissue results at each point. Becoming skilled in the use of these instruments often takes a little time, but the time is well well spent, in that it is now possible to perform an intestinal resection without resort to a single tie. BOWEL RESECTION

The precise techniques involved in resecting specific bowel segments will not be discussed in great detail here. (Colonic rements section, for example, is described elsewhere [see 5:34 Segmental ].) The following discussion outlines only the Col on on R esection section].) general principles. Preparation The segment of bowel to be removed must be isolated with an adequate resection margin.To this end, all surrounding adhesions adequate are divided. Next, the mesentery mesentery is divided.The key consideration consideration in this step is to preserve the blood supply to the two remaining ends of bowel while still achieving adequate excision of the diseased bowel. This is more easily accomplished in the small bowel than in the large bowel, bowel, thanks to the ample blood supply of the former; even so, transill transilluminati umination on of the mesentery mesentery and careful careful division of the vascu vascular lar arcade arcade are vital. In the colon, the sursurrounding fat and the appendices epiploicae should shoul d be cleared from the remaining bowel ends so that subsequent suture placement is straightforward.

© 2003 WebMD ebMD,, Inc. All rights reserved. reserved. 5 Gastr oin tes testi ti nal T ract and and Abd omen

ACS Surgery: Principles and Practice 29 I nt esti nal Anastomosis Anastomosis — 8

Care should be taken taken to avoid avoid two common common problems. First, ties placed close to the bowel can bunch tissues excessively and thereby cause angulation or distortion of the free edge of the intestine, which can make the anastomosis difficult and threaten the blood supply suppl y. Second Second,, beca because use mesenteric mesenteric vessels vessels are usually usually tied very close to their ends, the arteries sometimes slip back beyond the ties. Such slippage results in a hematoma within the leaves of the mesentery, which can itself threaten the viability of the the bowel. Generally, the bleeding vessel vessel can be secured with with a fine stitch; stitch; sometimes, howev however, er, a limited further bowel bowel resection is the only safe course of action. Both of these problems can be avoided by using the ultrasonic scalpel or the bipolar coagulating electrocautery. Division of Bowel If staplers are not available, the bowel segment to be removed is isolated between noncrushing clamps placed across the intestinal lumen some distance away from the resection margin so as to limit the amount of bowel contents that can escape into the wound. Crushing clamps are then placed placed on the specimen side of the diseased segment at the point of the the resection, and the bowel is divided with a knife just proximal and distal to the clamps. Thus, the lumen of the diseased segment is never open within within the abdominal wound. Even so,the so, the contents of the bowel between between the open ends and the noncrushing clamps can leak into the wound. To minimize this problem, it is usual to isolate the working area with abdominal abdominal packs, which are sometimes sometimes soaked soaked in an antiseptic (e.g., povido povidone-iodine) ne-iodine).. One advantage of using staplers for anastomosis is that in most instances, instance s, division of the bowel bowel can be accomplish accomplished ed without opening the lumen. lumen. A linear cutting cutting stapler stapler (e.g., GIA) transects transects the bowel and seals the two cut ends simultaneo simultaneously usly.. Unfortunately,, in the pelvis, it is usually necessary to employ an angulated ly angulated noncutting linear stapler (e.g., TA) so as to obtain as much length as possible distal to the lesion.The proximal rectum is then clamped with a crushing bowel bowel clamp, and a long knife is used to transect the rectum above above the staple line. Even so,there so, there remains the potenpotential for leakage of a small amount of fecal fecal material, which must then be suctioned away. SIMPLE BOWEL CLOSURE

There are many cases in which simple closure of a hole in the bowel is required, as with a perforated bowel perforated duodenal duodenal ulcer, a gunshot wound, or the inadvertent perforation perforation of the small bowel bowel during the division of dense peritoneal peritoneal adhesions. adhesions. Most surgeons close close such holes with two two layers of soluble suture material material (e.g., 2-0 polyglycolic polyglyc olic acid). My own preference is for an inner continuous layer inverted inverted with outer seromuscular seromuscular interrupted sutures, sutures, but there are many perfectly satisfactory alternatives. Special mention should be made of the technique of strictureplasty, which is used for a number of benign small bowel bowel strictures (especially those resulting from Crohn disease) as a means of avoiding avoid ing small bowel resection resection and anastomoses. anastomoses. In this procedure, the bowel bowel is opened longitudinally and closed transversely transversely with a single layer of 2-0 polyglycolic acid sutures in a Connell stitch. Excellent functional functional results have have been achieved with this technique techniq ue despite its reputation reputation for fistula fistula formation, which is associated with Crohn disease. SINGLE-LAYER SUTURED EXTRAMUCOSAL SIDE-TO-SIDE ENTEROENTEROSTOMY

5] may be performed A side-to-side anastomosis [see [see Figure 5] when no resection resection is done, as a bypas bypasss procedure procedure (e.g., (e.g., a gas-

Figure 5 Single-layer sutured extramucosal side-to-side enteroenterostomy.. A full-length suture is started in the back wall enteroenterostomy and run through the seromuscular and submucosal layers in the direction of the surgeon; surgeon; the corners of the enterotomy enterotomy are approximated with a baseball stitch, and a single Connell stitch is used to invert the anterior layer. layer. A second suture is started at the same spot on the posterior wall and run in the opposite direction, again through all layers layers except the mucosa; the corners of the enterotomies are approximated approximated with a baseball stitch, stitch, and the suture is continued in either the Connell stitch or the over-andover stitch to complete the anterior wall of the anastomosis.

troenterostomy); troenterostomy ); after a small bowel bowel resection; when there is a discrepancy in the diameter of the two ends to be anastomosed (e.g., an ileocolic anastomosis after a right hemicolectomy); or when the anatomy is such that the most tension-free position for the anastomosis is with the two bowel segments parallel (as in a Finney strictureplasty). Two stay sutures of 3-0 polyglycolic acid are placed approximately 8 cm apart on the inner aspect of the antimesenteric border. A 5 cm enterotomy is made on each loop with an electroelectrocautery or a blade on the inner aspect of the antimesenteric border. If electrocautery electrocautery is used, care must be be taken not to injure injure the mucosa of the posterior wall wall during this maneuver; placeme placement nt of a hemostat into the enterotomy to lift the anterior anterio r wall usually prevents this this problem. problem. Hemosta Hemostasis sis of the cut cut edges is ensured, ensured, and the remaining enteric contents contents are gently suctioned out. A swab soaked in povidone-iodine povidone-iodin e may be used at this point to cleanse the lumen of the bowel in the perianastomotic region. A full-length seromuscular and submucosal stitch of 4-0 polyglycolic acid is placed and tied on the inside approximately 5 to 10 mm from the far end of the enterotomies.The stitch is not passed through the the mucosa: to do so would add no strength to the anasanastomosis and would hinder epithelialization by rendering the tissue ischemic. A hemostat is placed on the the short end of the tied suture, and the assistant applies continuous gentle gen tle tension to the long end of the suture. An over-and-over stitch is started in the direction of the surgeon; surgeon; small bites bites are taken, and proper proper inversion inversion of the the suture line is ensured with each pass through through tissue. When the proximall ends of the enterostomies proxima enterostomies are reached, this so-called so-called baseball stitch is continued almost completely around to the anterior wall of the anastomosis. A single Connell stitch may be used to invert this anterior layer. Another full-length seromuscular and submucosal suture of 40 polyglycolic acid is then inserted and tied at the same location in the posterior wall as the first. If the two sutures are placed close enough together, together, the short ends need not be tied together together and may simply be cut off.The remainder of the posterior wall is sewn




29 I ntes ntesti ti nal Anastom Anastom os osis is — 9

away from the surgeon in the same manner as the portion already sewn, and the corners are appro approximate ximated d with the baseball stitch. stitch. The anterior wall is then completed with this second suture, either with the Connell stitch or with an over-and-over stitch with the assistant inverting the edges before applying tension to the previous stitch. When the defect is completely completely closed, the two sutures sutures are tied across the anastomotic line.The stay sutures are removed, removed, and the anastomosis anastom osis is carefully carefully inspected inspected.. Often, there is no mesenteric mesenteric defect to close close in a side-to-side side-to-side anastomosis, anastomosis, but if there there is one, it should be approximated at this point with continuous or interrupted absorbable absorbable sutures, with care taken not to injure the vascular supply to the anastomosis. DOUBLE-LAYER SUTURED END-TO-SIDE ENTEROCOLOSTOMY

In this procedure, the end of the ileum is joined to the side of the transverse colon [see [see Figure 6 ].The ].The distal colon is divided with a cutting stapler so that that a blind end is left. Some surgeons underpin or bury this staple line, though this practice is probably unnecessary.The proximal cut end of the intestine is similarly closed either with staples after division with a cutting linear stapler or with a crushing bowel clamp.This proximal end is brought into apposition with the side of the distal bowel segment at a point no farther than 2.5 to 5 cm from the blind end of the the distal segment; this proximity to the cut end is important for prevention of the blind loop syndrome. Stay sutures of 3-0 polyglycolic acid are placed between the serosa of the proximal limb, about 10 to 15 mm from the the clamp, and the serosa of the the distal limb. Interrupted seromuscular sutures of 3-0 polyglycolic acid are then placed between these stay sutures, spaced about three to six six to the centimeter.These stitch-

a

es may be tied sequentially or snapped and tied once they are all in place. It is crucial not to apply excessive excessive tension, tension, which could could cut the seromuscular layer layer or render it ischemic. ischemic. Suction is then readied.The readied. The staple line or crushed tissue on the proximal limb is cut off with a coagulating electrocautery electrocautery or a knife; this maneuver opens the lumen of the proximal limb. limb. All residual intestinal content is gently suctioned. An enterotomy or colotomy is created on the distal limb opposite the open lumen of the proximal bowel. bowel. A full-thickness suture of 3-0 polyglycolic acid is inserted in the posterior wall at a point close to the far end of the enterotomy and run in an over-and-over stitch back toward toward the surgeon. The corner is rounded with the baseball baseba ll stitch, and when the anterior wall wall is reached, the Connell stitch is used. A second full-length 3-0 suture is started at the same point on the posterior posterior wall as the first, and the short ends of the two sutures are tied together and cut.This cut. This second suture is then run away from the surgeon to complete the the posterior wall, and the anterior wall is completed with the Connell stitch.The stitch. The two sutures are then tied across the anastomotic line. A second series of interrupted seromuscular stitches is then placed anteriorly in the same fashion as the seromuscular stitches placed in the posterior posterior wall. It is important not to narrow either lumen excessively by imbricating too much of the bowel wall into this second layer. The lumen of the anastomosis is palpated to confirm patency, patency, and the mesenteric defect defect is closed if possible with either continuous or interrupted absorbable sutures. DOUBLE-STAPLED END-TO-END COLOANAL ANASTOMOSIS

Resection of the distal sigmoid colon and the rectum is a common procedure. procedure. In the past,it past, it often resulted resulted in a permanent colostomy because of the technical difficulties associated with a hand-sewn

b

c

Figure 6 Double-layer sutured end-to-side enterocolost entero colostomy omy.. (a) The proximal bowel end is stapled, interrupte interrupted d Lembert stitches are used to form the posterior outer layer, layer, and a colotomy colotomy is made. made. (b) Two continuous sutures are used to form the inner layer of the anastomosis; the posterior portion is done with the over-and-over over-and-over stitch, the anterior with the Connell Conne ll stitch. stitch. (c) Interrupted Lembert stitches are used to form the anterior outer layer.




a

29 I nt esti nal Anastomosis Anastomosis — 10

b

c

e

d

end-to-end coloanal anstomosis. (a) The C-EEA stapler comes with both a Figure 7 Double-stapled end-to-end standard anvil (left) and a trocar attachment attachment (right). (b) The rectal stump is closed with an angled linear noncutting stapler. A purse-string suture is placed around the colotomy colotomy,, and the anvil of the stapler is placed in the open end end and secured. (c) The stapler, stapler, with the sharp sharp trocar attachment in place, is inserted into the anus, and the trocar is made to pierce the rectal stump at or near the staple line, after which the trocar is remov removed. ed. (d ) The anvil in the proximal colon is joined with the stapler in the r ectal stump, and the two edges are slowly brought together. together. (e) The stapler is fired and then gently withdrawn.

anastomosis deep in the pelvis.The development of circular staplers reduced the technical difficulty of the operation and made possible anastomoses as far down as the anus [see [see Figure 7 ]. ]. Proper preparation of the patient and the bowel is essential before resection of the rectum. The patient is placed in the lithotomy position with the head tilted down, down, and the small bowel bowel is packed away in the upper abdomen.This positioning g ives the surgeon the best access to the pelvis. The splenic flexure and all of the distal large bowel are fully mobilized along with the rectum.The proximal resection margin is determined and cleared of serosal fat, and the bowel bowel is divided either with a GIA stapler or between crushing bowel clamps. An angled TA stapler is fired across the distal rectal resection margin, and another another bowel clamp clamp is placed proximal proximal to it. The rectum rectum is divided divided with a long-ha long-handled ndled knife, knife, with care care

taken to avoid plunging plunging the blade into the pelvic sidewall, which could cause significant neurovascular damage. The specimen is removed and the stapler stapler withdrawn. Adequate pelvic hemostasis is ensured. Once the surgeon is satisfied that the bowel is sufficiently mobilized, a noncrushing bowel bowel clamp is placed on the colon 10 to 15 cm proximal proximal to the margin, and the crushing clamp clamp is removed. removed. At this stage, stage, it is usual to create an 8 to 10 cm colonic colonic J pouc pouch; h; thi thiss measure typically yields a substantially improved functional outcome, especially in the early postoperativ postoperative e period in in older 77 patients. A whip-stitch (or purse-string suture) of 2-0 polypropylene is placed around the colotomy, colotomy, and the anvil from the appropriately sized curved EEA stapler is inserted into the open end and secured in place by tying the suture [see [ see Figure 7 ]. ]. The proximal proximal bowel clamp is removed. removed.The The assistant—who may also, also, if desired,




29 I nt esti nal Anastom Anastom os osis is — 11

gently wash out the rectal stump with a dilute povidone-iodine solution—performs a digital rectal examination. The stapler, stapler, with its trocar trocar attachmen attachmentt in place, is then inserted into the anus under the careful guidance guidance of the surgeon. The pointed shaft is brought out through or adjacent to the linear staple line, and the sharp point is removed.The removed.The peg from the anvil in the proximal colon is snapped into the protruding shaft of the stapler, and the two edges are slowly slowly brought together. together.The The colonic mesentery must not be twisted, and the ends must come together without any tension tension whatsoeve whatsoever. r. The stapler stapler is fired, and a distinctive crunching sound is heard. The anvil is then loosened the appropriate approp riate amount, amount, and the entire entire mechanism mechanism is withdrawn withdrawn through the the anus. Finally Finally,, the proximal proximal and distal rings of tissue, tissue, which remain remain on the stapler, are carefully inspected inspected to confirm circumferential closure of the staple line. The pelvis is then filled with body-temp body-temperature erature saline, saline, and a Toomey or bladder syringe is used to insufflate the neorectum with air.The air. The surgeon watches for bubbling in the pelvis as a sign of leakage from from the anastomosis anastomosis.. If there is a leak, leak, additiona additionall soluble sutures must be placed to close the defect and another air test performed. A rectal tube may then be inserted by the assistant assistant or may be placed at the end of the procedure. When the anastomosis is very low or there is some concern about healing, a drain may be placed in the pelvis behind the staple line; line; how howeve ever, r, as noted noted [see [see Controversial Issues in Intestinal Anastomosis, above ], this practice practice has not been shown shown to be benabove], eficial and may in fact impair impair healing. healing. Some surgeons prefer prefer to protect the anastomosis with a temporary proximal defunctioning stoma. There is some evidence that such protection reduces the

risk of an anastomotic anastomotic leak, but it is unclear unclear whether whether a loop ileostomy or a loop colostomy is better for this purpose. 78-82 Conclusion

A general note about the cosmetic aspect of these procedures is appropriate approp riate here. here. After any any of these operat operations, ions, a close visual inspection of the entire circumference of the anastomosis should be performed. As a rule, if the divided divided ends appear appear well apposed, apposed, then the anastomosis is probably sound. Over the past 200 years, our understanding of how the bowel bowel heals and how to perform intestinal anastomoses safely and effectively has improved considerably. considerably. This improvement is reflected in lower anastomotic anastomotic leakage and dehiscence rates, lower operative operative morbidity, and lower lower mortality. mortality. Some would would argue that much of the improved outcome is attributable to improved improved anesthesia, more potent antibiotics, antibiotics, and better postoperative postoperative monitoring and care. No doubt there is a good deal of truth to this argument.There is also no doubt, howev however, er, that one of the most most significant determinants of outcome after procedures that include intestinal anastomosis is surgical technique.The technique. The central importance of meticulous technique means that constant practice and careful attention to detail are essential essential for all surgeons operating on the the GI tract. In addition, it is important that that academic surgeons in particular continue to research such issues as the best suture material or stapler for specific operations, the most suitable and best-tolerated best-tolerated type of bowel preparation, the mechanisms mechanisms and variables involved involved in wound healing healing and collagen collagen deposition, and the importance of local and systemic factors in determining overall outcome.

References 1. Smith Smith SRG, SRG, Con Connol nolly ly JC, Cra Crane ne PW:The PW:The effect effect of surgical drainage materials on colonic healing. Br J Surg 69:153, 69:153, 1982 2. Matheso Matheson n NA, NA, McIn McIntosh tosh CA, Kruk Krukows owski ki ZH: Continuing experience with single layer appositional anastomosis in the large bowel. Br J Surg 72(suppl):S104 72(supp l):S104,, 1985 3 . C ar ar ty ty NJ NJ , K ea eat in ing J, J, C am amp be be ll ll J, J, e t a l: l: Prospective audit of an extramucosal technique for intestinal intestinal anastomosis. anastomosis. Br J Surg 78:1439, 1991 4. Debas Debas HT, HT, Tho Thomps mpson on FB: FB: A critical critical revie review w of colectomy colecto my with with anastomosis. anastomosis. Surg Gynecol Gynecol Obstet 135:747, 1973 5. Schroc Schrock k TR, TR, Dev Devene eney y CW, CW, Dun Dunphy phy JE: JE: Fa Factor ctorss contributing to leakage of colonic anastomoses. Ann Surg Surg 177:513, 1973 6. Halsted Halsted W: Circula Circularr suture of of the intestine— intestine—an an experimental experim ental study study.. Am J Med Sci 94:436, 1887 7. Hast Hastin ings gs JC, JC, Van Wi Wink nkle le W, Ba Barke rkerr E, et al: al: Effects of suture materials on healing of wounds of the stomach and colon. Surg Gynecol Obstet 140:701, 140: 701, 1975

11. Hawley Hawley PJ, PJ, Fau Faulk lk WP: A circulati circulating ng collage collagenase nase inhibitor. inhib itor. Br J Surg Surg 57:900, 57:900, 1970 12. Martens Martens M, Hen Hendrik drikss T: Po Posto stopera perativ tive e changes changes in collagen synthesis in intestinal anastomoses of the rat: differences between small and large bowel. bow el. Gut 32:1482, 1991 13. Marte Martens ns M, M, de deMa Man n B, He Hend ndrik rikss T, et al: al: Col Col-lagen synthetic capacity throughout the uninjured and anastomosed intestinal wall.Am J Surg 164:354, 164: 354, 1992 14. Guler Guler M, M, Kol Kologl oglu u M, M, Kam Kama a NA, NA, et al: al: Eff Effect ect of topically applied charged particles on healing of colonic colon ic anastomoses. anastomoses. Arch Surg 137:813, 2002 15. Fing Finger erhu hutt A, Ha Hay y JJ-M, M, El Elha hada dad d A, et al al:: Su Su-praperitoneal colorectal anastomosis: anastomosis: hand-sewn versus circular staples—a controlled clinical trial. Surgery Surge ry 118:479, 1995 16. Koruda Koruda MJ, Rol Roland andell ellii RH: Exp Experim eriment ental al studstudies on the healing of colonic anastomoses. J Surg Res 48:504, 1990 17. Munda Munday y C, McG McGinn inn FP: FP: A comparis comparison on of polypolyglycolic acid and catgut sutures in rat colonic anastomoses anast omoses.. Br J Surg Surg 63:870, 1976

8. Wise Wise L, McAl McAlist ister er W, Ste Stein in T, et al: al: Stu Studie diess on the healing of anastomoses of small and large intestines. intest ines. Surg Gynecol Gynecol Obstet 141:190, 141:190, 1975

18. Khubchanda Khubchandani ni IT: Low end-to-s end-to-side ide rectoenteri rectoenteric c anastomosis anast omosis with single-la single-layer yer wire. Dis Colon Rectum 18:308, 1975

9. Hesp Hesp F, F, Hen Hendrik drikss T, Lub Lubbers bers E-J E-J,, et al: al: Woun ound d healing healin g in the intestin intestinal al wall: wall: a comparison comparison between experimental ileal and colonic anastomoses.. Dis Colon moses Colon Rectum Rectum 24:99, 24:99, 1984

19. Irvin Irvin T, T, Gol Goligh igher er J: Aet Aetiol iology ogy of disrup disruptio tion n of intestinal intest inal anastomose anastomoses. s. Br J Surg 60:461, 1973

10. Hawley Hawley PJ, PJ, Hun Huntt TK, Dun Dunph phy y JE: Aet Aetiol iology ogy of colonic colon ic anastomotic anastomotic leaks. leaks. Proc R Soc Med Med 63:28, 63:2 8, 1970

20. Olse Olsen n GB, Le Letw twin in E, Wi Will llia iams ms HTG: HTG: Cl Clin inica icall experience with the use of a single-layer intestinal anastomos anastomosis. is. Can J Surg 56:771, 56:771, 1969 21. Sarin S, Lightw Lightwood ood RG: Conti Continuous nuous single single-lay -layer er gastrointestinal anastomosis: a prospective audit.

Br J Surg 76:493, 1989 22. Shan Shanda dall ll A, A, Lo Lown wnde dess R, You oung ng HL: HL: Co Colo loni nic c anastomotic anast omotic healing healing and oxygen oxygen tension. Br J Surg 72:606, 1985 23. Jibo Jiborn rn H, Ah Ahon onen en J, Ze Zede derf rfel eldt dt B: He Heal alin ing g of experimental colonic anastomoses: the effect of suture technique on collagen metabolism in the colonic colon ic wall. wall. Am J Surg 139:406, 1980 24. Khoury GA, Waxman BP: Large bow bowel el anasto anasto-mosis: I. The healing healing process and sutured sutured anastomoses: tomose s: a review review.. Br J Surg Surg 70:61, 70:61, 1983 25. Abramowitz Abramowitz H: Evertin Everting g and inv inverting erting anasto anasto-moses: an experimental experimental study study of comparative comparative safety.. Rev Surg safety Surg 28:142, 28:142, 1971 26. Polglase Polglase AL, Hughe Hughess ESR, ESR, McDermot McDermottt FT, et al: al: A comparison of end-to-end staple and suture colorectal anastomosis in the dog. Surg Gynecol Obstet 152:792, 1981 27. O’Neil O’Neil P, Hea Healey ley JEJ, JEJ, Cla Clark rk RI, RI, et al: al: Non Nonsut suture ure intestinal intest inal anastomosis anastomosis.. Am J Surg 104:761, 1962 28. Orr NWM: A single single layer layer intestinal intestinal anastomosi anastomosis. s. Br J Surg Surg 56:77, 56:77, 1969 29. Temp emplet leton on JL, McK McKelv elvey ey STD: Low colore colorecta ctall anastomoses: an experimental assessment of two sutured and two stapled techniques. Dis Colon Rectum 28:38, 1985 30. Goligh Goligher er J, Morri Morriss C, McA McAdam dam W: A control controlled led trial of inverting versus everting intestinal suture in clinical large-bowel surgery. Br J Surg 57:817, 1970 31. Bruniu Bruniuss U, Zed Zederfe erfeldt ldt B: Eff Effects ects of antiin antiinflam flam-matory treatment on wound healing. healing. Acta Chir Scand 129:462, 1965




32. Fieldi Fielding ng LP, Ste Stewart wart Brow Brown n S, Ble Blesow sowsky sky L, L, et al: Anasto Anastomotic motic integrity integrity after operations operations for large bowel bowel cancer: a multicentre multicentre study. study. Br Med J 282:411, 1980 33. Leob Leob MJ: Com Compar parati ative ve streng strength th of inverted inverted,, everted and endon intestinal anastomoses. Surg Gynecol Gynec ol Obstet 125:301, 1967 34. Undre Undre AR: AR: Ent Entero eropla plasty sty:: a new conce concept pt in the the management of benign strictures of the intestine. Int Surg Surg 68:73, 1983 35. Chassin Chassin JL, JL, Rifk Rifkind ind KM,Turn KM,Turner er JW: Erro Errors rs and pitfalls in stapled gastrointestinal tract anastomoses.. Surg Clin moses Clin North Am 64:441, 1984 36. Ravitch Ravitch MM: Intersect Intersecting ing staple staple lines lines in intestiintestinal anastomo anastomoses. ses. Surge Surgery ry 97:8, 1985

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suture. North American suture. American Practitio Practitioner ner 4:481, 1892 51. Ballan Ballantyn tyne e GH: The experim experimenta entall basis of intestinal suturing: effect of surgical technique, inflammation and infection on enteric wound healing. healin g. Dis Colon Colon Rectum Rectum 27:61, 1984 52. O’Dwye O’Dwyerr PJ, Con Conwa way y W, McD McDermo ermott tt EWM, EWM, et al: Effect of mechanical mechanical bowel bowel preparation preparation on anastomotic integrity following low anterior resection resecti on in dogs. dogs. Br J Surg 76:756, 76:756, 1989 53. Goligh Goligher er JC, Gra Graha ham m NG NG,, De DeDom Domba ball FT: FT: Anastomotic dehiscence after anterior resection of the rectum and and sigmoid. sigmoid. Br J Surg 57:109, 1970

anastomosis anastomo sis of the intestine. intestine. Surg Gynecol Gynecol Obstet 139:93, 1974 69. Ravitch Ravitch MM, Steich Steichen en FM:Techni FM:Techniques ques of staple staple suturing in the gastrointestinal tract. Ann Surg 175:815, 175: 815, 1972 70. Burg Burg R, Gei Geigle gle C, C, Fas Faso o J, et al: al: Omi Omissio ssion n of rouroutine gastric decompression decompression.. Dis Colon Rectum 21:98, 21:9 8, 1978 71. Reasbe Reasbeck ck P, Ric Rice e M, Herb Herbiso ison n G: Nasoga Nasogastri stric c intubation after intestinal resection. Surg Gynecol Obstet Obstet 158:354, 1984 72. Argov S, Goldst Goldstein ein I, Barzil Barzilai ai A: Is routine routine use of of a nasogastric tube justified in upper abdominal surgery? Am Am J Surg 139:849, 1980

37. Chung RS: Blood flow in in colonic colonic anastomose anastomoses: s: effect of staplin stapling g and suturing. suturing. Ann Surg Surg 206:335, 206: 335, 1987

54.. Fok M, 54 M, Ah Ah-C -Cho hong ng AK AK,, Ch Chen eng g SWK, SWK, et al: al: Comparison of a single layer continuous handsewn method and circular stapling in 580 esophageal esopha geal anastomoses anastomoses.. Br J Surg 78:342, 1991

38. Julian Julian TB, Ravit Ravitch ch MM: Evalu Evaluation ationss of the safety of end-to-end stapling anastomoses across linear stapled closure. Surg Clin North Am 64:567, 1984

55. Hock Hockin ing g M, Ca Carls rlson on R, R, Co Couri uring ngto ton n K, et al: al: Altered motility and bacterial flora after functional end-to-end end-to-end anastomosis. anastomosis. Surgery 108:384, 1990

39. Brenna Brennan n SS,Pickford SS,Pickford IR,Evans M,et al: Sta Staple pless or sutures for colonic anastomosis—a controlled clinical clinic al trial. trial. Br J Surg 69:722, 69:722, 1982

56. West of Scotland and Highland Highland Anastomo Anastomosis sis Study Group: Group: Suturi Suturing ng or stapling stapling in gastrointestinall surgery: intestina surgery: a prospective prospective randomiz randomized ed study.. Br J Surg study Surg 78:337, 78:337, 1991

75. Merad Merad F, F, Hay JM, Fin Finger gerhut hut A, et al: al: Is proph prophyylactic pelvic drainage useful after elective rectal or anal anastomosis? A multicentre controlled randomized rando mized trial. French Associat Association ion for Surgical Researc Research. h. Surgery 125:529, 1999

57. Irving Irving AD AD,, Scri Scrimge mgeour our D: Mec Mechan hanica icall bowel bowel preparation for colonic resection and anastomosis. Br J Surg 74:580, 1987

76. Manz Manz CW, CW, LaTend endress resse e C, Sak Sako o Y: The detri detri-mental effects of drains on colonic anastomoses. Dis Colon Rectum Rectum 13:17, 1970

58. Hughes Hughes ESR: Asepsis in large large bowel bowel surgery surgery.. Ann R Coll Surg Engl Engl 51:347, 1972

77. Sailer Sailer M,Fuchs K-H, K-H, Fe Fein in M,et al: Ran Random domized ized clinical trial comparing quality of life after straight and pouch coloanal reconstruction. Br J Surg 89:1108, 2002

40. O’Donn O’Donnell ell AF, AF, O’C O’Conn onnell ell PR, Roy Roysto ston n D, et al: Suture technique affects perianastomotic colonic crypt cell production and tumour formation. Br J Surg Surg 78:671, 1991 41.. Gree 41 Greens nste tein in A, Ro Roge gers rs P, P, Mo Moss ss G: G: Do Doub uble led d fourth-day colorectal anastomotic strength with complete retention of intestinal mature wound collagen and accelerated deposition following full enteral enteral nutrition. nutrition. Surgery Forum Forum 29:78, 1978 42. Bubrick Bubrick MP: Effects of of technique technique on anasto anastomotmotic dehiscence. dehiscence. Dis Colon Rectum Rectum 24:232, 24:232, 1981 43. Lafreni Lafreniere ere R, Ketc Ketcham ham AS: AS: A single single layer layer open anastomosis anast omosis for all intestinal intestinal structures. structures. Am J Surg 149:797, 1985 44. Beart Beart RW, RW, Kell Kelly y KA: Ran Random domized ized prosp prospecti ective ve evaluation of the EEA stapler for colorectal anastomoses. tomose s. Am J Surg Surg 141:143, 141:143, 1981 45. Krach Krachtt M, M, Ha Hay y J-M J-M,, Fa Fagn gnie iezz P-L P-L,, et al al:: Il Ileoeocolonic anastomosis after right hemicolectomy for carc carcinom inoma: a: stap stapled led or hand hand-sew -sewn. n. Int J Colorectt Dis 8:29, 1993 Colorec 46. Valv alverd erde e A, Hay JM, JM, Fin Finger gerhut hut A, et al: al: Man Manual ual versus mechanical esophagogastric anastomosis after resection for carcinoma: a controlled trial. French Association for Surgical Research. Surgery Surge ry 120:476, 1996 47. Akyo Akyoll AM, AM, Mc McGr Greg egor or JR, JR, Ga Gall llow oway ay DJ, DJ, et al: al: Recurrence of colorectal cancer after sutured and stapled large bowel bowel anastomoses. Br J Surg 78:1297, 78:1 297, 1991 48. O’Dwye O’Dwyerr P, Rav Raviku ikumar mar TS, Ste Steele ele G: Seru Serum m dependent variability in the adherence to tumour cells to surgical surgical sutures. sutures. Br J Surg 72:466, 1985 49. Everet Everettt WG, Frie Friend nd PJ, PJ, Fo Forty rty J: Com Compari parison son of of stapling and hand-suture for left-sided large bowell anastomosis bowe anastomosis.. Br J Surg 73:345, 73:345, 1986 50. Murphy JB: JB: A contribution contribution to abdomin abdominal al surgery, ideal approximation of abdominal viscera without

59. LeVeen LeVeen HH,Wapni HH,Wapnicks cks S, Falk D: Effect Effectss of proprophylactic phyl actic antibiotics antibiotics on colonic colonic healing. Am J Surg 131:47, 1976 60. Irvin Irvin T, Gol Goligh igher er J, Joh Johnst nston on D: D: A random randomized ized prospective clinical trial of single-layer and twolayer inverting inverting intestinal anastomoses. Br J Surg 60:457, 60:4 57, 1973 61. van van Gelde Geldere re D, D, FaFa-SiSi-Oen Oen P, Noa Noach ch LA, LA, et al: al: Complications after colorectal surgery without mechanical bowel bowel preparation. J Am Coll Surg 194:40, 194: 40, 2002 62. Bozetti Bozetti F: Perio Perioperati perative ve nutriti nutrition on of patien patients ts with gastrointestinal cancer. Br J Surg 89:1201, 2002 63. Munck Munck A, Guy Guyre re M, Hol Holbro brook ok N: Phy Physio siologi logical cal functions of glucocorticoids in stress and their relation to pharmacological actions. Endocrinol Rev 5:25, 1984 64. Matsusue Matsusue S,Walser S,Walser M: Heali Healing ng of intestinal intestinal anasanastomoses in adrenalectomized rats given corticosterone. steron e. Am J Physiol Physiol 263:R164, 263:R164, 1992 65. Quan Z, Walser M: The effect effect of corticost corticosterone erone administration at varying levels on leucine oxidation and whole body protein synthesis and breakdown in adrenalectom adrenalectomized ized rats. Metabolism 40:1263, 40:1 263, 1991 66. Gadacz Gadacz T, Men Menguy guy RB: RB: Eff Effect ectss of anti-infl anti-inflamammatory drug oxyphenbutazone on the rate of wound healing and the biochemical composition of wound wound tissue. Surgery Forum Forum 18:58, 1967 67. Getzen Getzen L: L: Int Intest estina inall anast anastomo omoses ses.. Curr Pro Probl bl Surg, Sur g, Aug August ust 1969, 1969, p 3 68. Kra Kratzer tzer GL, GL, Ons Onsani anitt T: T: Sin Single gle layer layer steel steel wire wire

73. Yates JL: An experimental experimental study study of the local local effects of peritoneal drainage. drainage. Surg Gynecol Obstet 1:473, 1:47 3, 1905 74. Berl Berlin iner er SD SD,, Bu Burso rson n LC, LC, Le Lear ar PE PE:: Us Use e and and abuse of intraperitoneal drains in colon surgery. Arch Surg Surg 89:686, 1964

78.. Gorfi 78 Gorfine ne SR SR,, Gel Gelern erntt IM, IM, Ba Baue uerr JJ, JJ, et al: al: Restorative proctocolectomy without diverting ileostomy. ostom y. Dis Colon Rectum Rectum 38:188, 38:188, 1995 79. Groble Groblerr SP, SP, Hos Hosie ie KB, KB, Kei Keighl ghley ey MR: MR: Ran Random dom-ized trial of loop ileostomy in restorative proctocolectomy colecto my.. Br J Surg 79:903, 79:903, 1992 80. Dehni Dehni N, Sch Schleg legel el RD RD,, Cun Cunnin ningha gham m C, C, et al: Influence of a defunctioning stoma on leakage rates after low colorectal anastomosis and colonic J pouchpouch-anal anal anastomo anastomosis. sis. Br J Surg 85:1114, 85:1 114, 1998 81. Law Law WL, WL, Chu KW, Cho Choii HK: Ran Random domized ized clinclinical trial comparing loop ileostomy and loop transverse colostomy for fecal diversion following total mesorectal mesorectal excision. Br J Surg Surg 89:704, 2002 82.. Edwa 82 Edward rdss DP, DP, Le Lepp ppin ingt gton on-C -Cla larke rke A, A, et al: al: Stoma-related complications are more frequent after transverse colostomy than loop ileostomy: a randomized prospective clinical trial. Br J Surg 88:360, 88:3 60, 2001

Acknowledgment Figure Fig uress 1 throu through gh 7

Tom Moor Moore. e.

Portions of this chapter are based on a previous iteration written for ACS Surgery by Zane Zane Cohen, M.D M.D., ., and Barry Sullivan, Sullivan, M.D M.D.. The author wishes wishes to thank Drs. Cohen and Sullivan. Sullivan.

Intestinal Anastomosis

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