Chapter 6. Incisions, Closures, and Management of the Abdominal Wound

The impact that the planning, execution, and closure of an incision has on the outcome of an abdominal operation should not be underestimated. The high combined incidence of surgical site infection (SSI), wound dehiscence, and hernia formation suggests a dominant contribution of wound complications to surgical morbidity. Moreover, the quality of exposure provided by an incision influences the ease and safety with which an operation can be undertaken and the outcome in ways which defy easy quantification.

An incision must provide access to the site of abdominal pathology and allow easy extension if greater exposure than originally anticipated is required. Indeed, the adequacy of an incision is determined above all else by the safety with which an operation can be undertaken. Nothing should compromise this and a larger incision or even, on occasion, a second incision should be created without hesitation if exposure is inadequate. Notwithstanding this, the incision should be executed in a fashion that anticipates a secure wound closure and interferes as little as possible with the function and cosmesis of the abdominal wall. These principles apply to both open and laparoscopic incisions. While the vertical midline incision remains most popular, and is, perhaps the most flexible, a variety of other incisions may have distinct advantages in specific settings.

Choice of Incision

Abdominal incisions can be vertically, transversely, or obliquely oriented. The avascular linea alba affords the vertical midline its superior flexibility. Indeed, when optimal exposure of the abdominal cavity is necessary (eg, exploration for abdominal trauma), the vertical midline incision is preferred and can be extended superiorly to the xiphoid process and inferiorly to the symphysis pubis. Alternatively, vertical incisions may be placed in a paramedian position, an approach that was previously more popular than it is today but continues to have its proponents. Transverse and oblique incisions can be placed in any of the four quadrants of the abdomen depending on the site of pathology. Common examples include the Kocher subcostal incision for biliary surgery, the Pfannenstiel infraumbilical incision for gynecologic surgery, and the McBurney and Rockey-Davis incisions for appendectomy. A bilateral subcostal incision affords excellent exposure of the upper abdomen. Alternatively, when superior exposure of upper abdominal organs (eg, the esophagogastric junction) is required, thoracoabdominal incisions may be used.

The relative merit of vertical versus transverse incisions remains a topic of active debate. Proponents of transverse incisions argue that they anticipate a more secure closure than do vertical incisions, a hypothesis supported by anatomic and surgical principle. The fascial fibers of the anterior abdominal wall are oriented transversely or obliquely. Therefore, transverse incisions parallel the direction of the fascial fibers and allow for ready reapproximation with sutures placed perpendicular to these fibers. In contrast, vertical incisions disrupt fascial fibers and must be reapproximated with sutures placed between fibers.1 In the latter case, the absence of an anatomic barrier may predispose such sutures to pull through tissue resulting in dehiscence or hernia formation. Despite these concerns, little evidence supports a substantial benefit of transverse incisions. A number of retrospective clinical studies and a meta-analysis do suggest that transverse incisions are superior to vertical incisions with regard to long-term and short-term outcomes (eg, postoperative pain, pulmonary complications, and frequencies of incisional hernia and dehiscence).1 Prospective data has been less definitive, however. One randomized controlled trial compared vertical and transverse incisions with regards to the frequency of evisceration; no significant difference in outcome was observed with either technique.2 In a more recent prospective randomized trial, no significant differences in 30-day mortality, pulmonary complications, median length of hospital stay, median time to tolerate solid food, and incisional hernia formation at 1 year were observed. More wound infections were seen with transverse incisions.3

Likewise, some controversy persists regarding the relative advantages of midline versus paramedian incisions. The theoretical advantage of a paramedian over a midline incision is a diminished risk of wound dehiscence and incisional hernia owing to the presence of rectus muscle interposed between layers of divided fascia. In practice, when these incisions are reopened, the medial edge of the rectus muscle is frequently found to be adherent to the posterior sheath incision and does not effectively buttress the wound. The potential advantages of the paramedian incision have also been investigated in prospective randomized trials which fail to demonstrate any advantage with regards to wound failure rates when compared to midline or transverse incisions.4 A “lateral paramedian incision” refers to a vertical incision created several centimeters lateral to the location of the traditional paramedian incision.5 One randomized prospective study suggested a statistically significant decrease in the incidence of incisional hernia following closure of lateral paramedian incisions (0%) compared to medial paramedian incisions (14.9%)6 and midline incisions (6.9%).7 A disadvantage of the paramedian incision is the greater length of time needed to create the wound, which increases with the distance from the midline.

In the patient who has had prior abdominal surgery, the cosmetic advantages of re-entering the abdomen through a preexisting scar must be balanced against the challenges associated with dissection in a reoperative field. Close proximity of a new incision to an old one should be avoided in order to minimize the risk of ischemic necrosis of intervening skin and fascial bridges.

Preparation of the Surgical Site

Prior to incision, the surgical field is prepared with antiseptic solution and draped in order to reduce skin bacterial counts and the likelihood of subsequent wound infection. Shaving prior to operation has been associated with an increased rate of SSI and should, therefore, be avoided. If hair at the surgical site will interfere with accurate wound closure or precludes thorough application of the sterile preparation, the use of clippers is preferred to a razor.8 A variety of antiseptic solutions are commonly used to prepare the skin, including povidone-iodine, alcohol, and chlorhexidene. The efficacy of povidine-iodine depends on the release of the active iodine from a carrier molecule. The solution should, therefore, be applied several minutes prior to incision to maximize its efficacy. The use of chlorhexidine gluconate has been associated with greater reductions in skin bacterial counts and lower rates of SSI when compared to povidine-iodine in a number of studies6,9,10 and is emerging as the preferred skin antiseptic.

Incisions: Technical Considerations

Vertical Incisions

Midline Incision.

The midline incision allows rapid access to, and adequate exposure of, almost every region of the abdominal cavity and retroperitoneum. It is typically associated with little blood loss and does not require transection of muscle fibers or nerves. The upper midline incision (ie, above the umbilicus) may be used to expose the esophageal hiatus, abdominal esophagus and vagus nerves, stomach, duodenum, gallbladder, pancreas, and spleen (Fig. 6-1). The lower midline incision (ie, below the umbilicus) provides exposure of lower abdominal and pelvic organs. When broad exposure is required, as in an exploration for trauma, the midline incision can be extended to the xiphoid process superiorly and to the pubic symphysis inferiorly.

In creating a midline incision, the operating surgeon and assistant apply opposing traction to the skin on both sides of the abdomen. The skin is then incised with a scalpel. Gauze pads are applied to the skin edges to tamponade bleeding cutaneous vessels and lateral traction is placed on the subcutaneous fat on both sides of the incision. The incision is then carried down to the linea alba using either electrocautery or a scalpel; the decussation of fascial fibers in the upper abdomen serves as an important landmark for the midline. The linea alba, extraperitoneal fat, and peritoneum are then divided sequentially. If exposure of both the upper and lower peritoneal cavities is required, the incision is carried around the umbilicus in a curvilinear fashion. The peritoneum itself is best divided with scissors or scalpel to avoid coagulation injury to underlying intraabdominal organs. Additionally, safe entry may be facilitated by picking up a fold of peritoneum, palpating it to ensure that no bowel has been drawn up, and sharply incising the raised fold. The falciform ligament is best avoided by entering the peritoneum to the left or right of the midline in the upper abdomen. To avoid injuries to the bladder, the peritoneum is entered in the upper portion of the incision. After a small opening is created in the midline, it is enlarged to accommodate two fingers that are then used to protect the underlying viscera as the peritoneum is further divided along the length of the wound (Fig. 6-2).

Paramedian Incision.

Paramedian incisions are vertical incisions placed either to the right or the left of the midline on the abdominal wall. Like midline incisions, paramedian incisions obviate division of nerves and the rectus muscle and may be made in the upper or lower abdomen. Superiorly, additional access can be obtained by curving the upper portion of the incision along the costal margin toward the xiphoid process (Fig. 6-3). The anterior border of the rectus sheath is exposed and incised across the entire length of the wound. The medial aspect of the anterior rectus sheath is then dissected away from the rectus muscle to its medial edge (Fig. 6-4). Particular care must be taken during this dissection in the upper abdomen where tendinous inscriptions that attach the rectus muscle to the anterior fascia are associated with segmental vessels. These vessels should be clipped or ligated when encountered to avoid significant bleeding. Once free, the rectus muscle is retracted laterally. The posterior sheath (above the arcuate line) and peritoneum are then incised to gain entry into the abdomen. During creation of a paramedian incision in the lower abdomen, the inferior epigastric vessels may be encountered and must be ligated prior to division (Fig. 6-5).

Vertical Muscle-Splitting Incision.

The vertical muscle-splitting incision is made in much the same way as the traditional paramedian incision except that the rectus muscle is split, rather than retracted laterally. This wound can be opened and closed quickly and is of particular value in reopening a previous paramedian incision where dissection of the rectus muscle away from the rectus sheath can be difficult. Longer incisions should be avoided, however, because they result in significantly more bleeding and sacrifice of nerves that may lead to weakening of the corresponding area of the abdominal wall.

Transverse and Oblique Incisions

Transverse and oblique incisions generally follow Langer's lines of tension and usually allow a more cosmetic closure than do vertical incisions. Importantly, the rectus muscle has a segmental nerve supply derived from intercostal nerves, which enter the rectus sheath laterally. Transverse or slightly oblique incisions through the rectus most often spare these nerves. Provided that the anterior and posterior sheaths are closed, the rectus muscle can therefore be divided transversely without significantly compromising the integrity of the abdominal wall. Although properly placed transverse incisions can provide exposure of specific organs, they may be limiting when pathology is located in both the upper and lower abdomen.

Kocher Subcostal Incision.

A right subcostal incision is used commonly for operations in which exposure of the gallbladder and biliary tree is necessary. The left-sided subcostal incision is used less often, mainly for splenectomy. A bilateral subcostal incision provides excellent exposure of the upper abdomen and can be employed for hepatic resections, liver transplantation, total gastrectomy, and for anterior access to both adrenal glands.

The standard subcostal incision begins at the midline, two fingerbreadths below the xiphoid process and is extended laterally and inferiorly, parallel to the costal margin (Fig. 6-6). The incision should not be placed too far superiorly as sufficient fascia must be preserved to allow a secure abdominal closure. Following incision of the rectus sheath along the plane of the skin incision, the rectus muscle is divided using electrocautery or ligatures to control branches of the superior epigastric artery. The peritoneum is then divided in the plane of the skin incision. The incision can be extended beyond the lateral aspect of the rectus muscle if necessary to facilitate exposure.

Mcburney and Rockey-Davis Incisions.

Originally described by Charles McBurney in 1894,11 the muscle-splitting right iliac fossa incision known as the McBurney incision is well suited for appendectomy. This incision is oriented obliquely. The McBurney incision has largely been supplanted by the Rockey-Davis incision, which is oriented transversely as opposed to obliquely, allowing for better cosmesis (Fig. 6-7).

The suspected position of the appendix and the thickness of the abdominal wall influence the placement of the incision as well as its length. Examination of the anesthetized patient's abdomen will often reveal a mass, guiding placement of the incision directly over the appendix. If no mass is palpable, the incision is centered over McBurney's point at the junction of the middle and outer thirds of the line between the umbilicus and the anterior superior iliac spine. If the patient is obese, or if extension of the incision is anticipated, the incision should be placed obliquely, allowing ready lateral extension.

After skin and subcutaneous tissues are incised, the external oblique aponeurosis is exposed and divided parallel to the direction of its fibers to reveal the underlying internal oblique muscle. At a point adjacent to the lateral border of the rectus sheath, a small incision is made in the internal oblique muscle, which is similarly opened in the direction of its fibers. Once the underlying transversalis muscle is exposed, it is split to reveal the transversalis fascia and peritoneum. These are sharply divided and the appendix and cecum are exposed (Fig. 6-8). If further exposure is necessary, the wound can be enlarged by dividing the rectus sheath, retracting the rectus muscle medially, and extending the peritoneal defect. If the operation requires extension of the wound laterally, this can be accomplished through division of the oblique muscles.

Pfannenstiel Incision.

The Pfannenstiel incision is used frequently for gynecologic operations and for access to the retropubic space (eg, for extraperitoneal retropubic prostatectomy). The skin incision is placed in the interspinous crease above the symphysis pubis. The anterior rectus sheath is exposed and divided transversely. The superior and inferior leaflets of the divided sheath are dissected from the underlying rectus muscles superiorly to the umbilicus and inferiorly to the pubic symphysis. The recti are retracted laterally and the peritoneum is opened vertically in the midline. At the inferior aspect of the wound, the bladder is protected to avoid injury (Fig. 6-9). An advantage of this incision is that it affords a cosmetic closure because it is placed in a skin crease at the level of the belt line; however, exposure may be somewhat limited.

Abdominothoracic Incisions

The thoracoabdominal incision provides enhanced exposure of upper abdominal organs. A left thoracoabdominal incision is useful for access to the left hemidiaphragm, gastroesophageal junction, gastric cardia and stomach, distal pancreas and spleen, left kidney and adrenal gland, and aorta. A right thoracoabdominal incision can be used to expose the right hemidiaphragm, esophagus, liver, portal triad, inferior vena cava, right kidney, right adrenal gland, and proximal pancreas. These incisions are reserved for circumstances in which an operation cannot safely be performed through an abdominal incision, as they are theoretically associated with increased morbidity relating to a more difficult pulmonary recovery and risk of phrenic nerve injury.

The patient is placed in the “corkscrew” position on the operating room table to enhance access to both the abdominal and thoracic cavities. The abdomen is tilted approximately 45 degrees from the horizontal plane and the thorax is oriented in full lateral position (Fig. 6-10A). Positioning is aided by the use of a bean bag. The abdominal part of the incision may consist of a midline or upper paramedian incision, which allows exploration of the abdomen. The incision is extended obliquely along the line of the eighth interspace just beneath the inferior pole of the scapula (Fig. 6-10B). Alternatively, an oblique upper abdominal incision can be used and extended directly into the thoracic portion of the incision.

After entry into the peritoneal cavity through the abdominal portion of the incision, the incision is extended onto the chest wall and the latissimus dorsi and serratus anterior muscles, and then the external oblique muscle and aponeurosis are divided. The intercostal muscles of the eighth interspace are divided to allow entry into the chest cavity and the incision is extended across the costal margin, which is divided with a scalpel. It is often useful to resect a short segment of costal cartilage to facilitate closure of the chest wall. A self-retaining rib retractor is inserted and the intercostal space is gently spread. The diaphragm is either incised radially toward the esophageal or aortic hiatus, or in a curvilinear fashion if less exposure is required. This incision also preserves phrenic nerve function and is useful for patients with pulmonary compromise.12

At the completion of the operation, chest tubes placed in the pleural cavity are brought out through the chest or upper abdominal wall through separate incisions. The diaphragm is repaired in two layers using nonresorbable sutures. Pericostal sutures are placed to reapproximate the ribs. The chest muscles and abdominal wall are then closed in layers.

Retroperitoneal and Extraperitoneal Incisions

Retroperitoneal and extraperitoneal approaches to the abdomen have several advantages over transperitoneal exposures. Manipulation and retraction of intraabdominal viscera are limited and postoperative ileus is reduced. Hemorrhage is more likely to be tamponaded in the retroperitoneum than when it occurs in the peritoneal cavity. Retroperitoneal and extraperitoneal approaches can be used for operations on the kidney, ureter, adrenal gland, bladder, splenic artery and vein, vena cava, lumbar sympathetic chain, abdominal aorta, iliac vessels, and on groin hernias.

Retroperitoneal Approach to the Lumbar Area.

The retroperitoneal approach to the lumbar area is frequently used for aortic surgery, nephrectomy, lumbar symphathectomy, and ureterolithomy. The patient is positioned with the operative side elevated 30–45 degrees with the knees and hips flexed. The incision extends from the lateral margin of the rectus sheath at the level of the umbilicus toward the twelfth rib for approximately 12–14 cm (Fig. 6-11). A portion of the twelfth rib is resected if necessary. The external oblique, internal oblique, and transversalis muscles are exposed, and divided in the direction of their fibers. The retroperitoneum is entered and the peritoneum and retroperitoneal fat are swept anteriorly. The lower pole of the kidney, ureter, and sympathetic chain are easily identified. The vena cava is exposed on the right and the aorta is exposed on the left. If the peritoneum is unintentionally entered, it is closed immediately with continuous absorbable suture. At the conclusion of the procedure, the retroperitoneal fat and viscera fall back into place and the muscles of the abdominal wall are reapproximated in layers.

Posterior Approach to the Adrenal Glands.

With the posterior approach, dissection is performed entirely in the retroperitoneal space. The patient is placed in the prone jackknife position. A curvilinear incision is made beginning on the tenth rib approximately three fingerbreadths lateral to the midline and carried inferiorly and laterally toward the iliac crest, ending approximately four fingerbreadths lateral to the midline (Fig. 6-12). The subcutaneous tissues are divided to expose the posterior layer of the lumbodorsal fascia. This fascia and the fibers of the latissimus dorsi muscle, which originate from it, are divided. The erector spinae muscle is exposed and retracted medially to uncover the twelfth rib and the middle layer of the lumbodorsal fascia. The attachments of the erector spinae to the twelfth rib are divided with electrocautery; the vessels and nerves that penetrate the fascia are secured with clamps and ligated. The twelfth rib is then resected. Gerota's fascia is exposed by incising the lumbodorsal fascia along the lateral margin of the quadratus lumborum muscle. The intercostal neurovascular bundle should now become visible directly below the bed of the resected twelfth rib. The intercostal vessels are clamped, divided, and ligated and the intercostal nerve is retracted downward. The posterior fibers of the diaphragm are identified and divided where they insert on the periosteum of the twelfth rib. The lower margin of the lung will enter the field with hyperinflation. If the pleura are inadvertently injured, the resulting pneumothorax is handled at closure by insertion of a large-bore rubber catheter into the pleural cavity, which is brought out through the wound. After closure of the fascial fibers around the catheter, the lung is hyperinflated evacuating all air from the pleural space, and the catheter is briskly removed.

Retroperitoneal Approach to the Iliac Fossa.

The retroperitoneal approach to the iliac fossa provides access to the bladder, distal ureter, and common, internal, and external iliac vessels. It is often employed for surgery on the iliac arteries and for kidney transplantation. It may also be used to drain psoas or retrocecal abscesses and to resect retroperitoneal tumors. The skin incision is oriented obliquely and extends from approximately 2 cm above the anterosuperior iliac spine to a point just lateral to the pubic symphysis (Fig. 6-13). The incision can also be extended superiorly as far as the costal margin, if necessary. The external oblique, internal oblique, and transversus abdominis muscles are divided in line with the skin incision. The retroperitoneum is entered and the retroperitoneal fat and peritoneum are swept superomedially. If the peritoneum is inadvertently entered, it is closed immediately. At the conclusion of the procedure, the retroperitoneal fat and viscera fall back into place and the muscles of the abdominal wall are reapproximated in layers.

Laparoscopic Incisions

As with open abdominal incisions, laparoscopic access must allow optimal exposure without unnecessarily compromising abdominal wall function or cosmesis. Laparoscopic incisions may be placed anywhere on the abdominal wall. When appropriate, laparoscopic incisions should allow for ready extension should conversion to open operation become necessary. Additionally, laparoscopic access may be combined with small open incisions that accommodate appliances through which a hand can be inserted into the peritoneal cavity without the loss of pneumoperitoneum. Such hand-assisted laparoscopic approaches are frequently associated with shorter operative times than are purely laparoscopic approaches and may have particular advantages for operation in which a larger incision is necessary to remove the surgical specimen (eg, laparoscopic colectomy) and more complex procedures.13 The initial step of any laparoscopic procedure is the establishment of pneumoperitoneum. This can be achieved using an open or closed technique. Access is most often obtained at a site just above or below the umbilicus; the thinnest portion of the abdominal wall and a central location from which all quadrants of the abdominal cavity can be visualized. Other sites are preferable in specific circumstances (eg, left upper quadrant access in a patient with a previous midline incision).

Initial Access

The open approach involves the creation of a small incision, generally 1.5 cm, through which the abdominal fascia is grasped with straight clamps and elevated toward the wound. Exposure of the fascia is often enhanced with the use of S-shaped retractors. The fascia and then peritoneum are divided under direct vision. Abdominal entry is confirmed by digital palpation. Heavy stay sutures are then placed in each fascial edge and are lifted up while a blunt-tipped (Hasson) obturator and cannula are inserted through the opening in the abdominal wall. The stay sutures are then wrapped around the struts on the cannula to secure it in position. Insufflation tubing is then attached to the cannula and the obturator is withdrawn. Carbon dioxide is insufflated into the abdomen to a pressure of 12–15 mm Hg.

The closed technique involves the passage of a sharp needle (Veress needle) through the abdominal wall into the abdominal cavity. A small skin incision is made in the skin through which the needle is inserted, generally at an angle of 45 degrees to the abdominal wall; an angle of 90 degrees is sometimes necessary in the obese patient. As the needle passes through the fascia and then the peritoneum, a sensation of overcoming resistance is appreciated, often reinforced by an audible click as the blunt tip of the needle springs forward. A 10 cc syringe containing 5 cc of saline is attached to the end of the needle and is aspirated. If enteric contents, blood or urine, are not aspirated, the saline is instilled through the needle. If the needle is appropriately placed in the peritoneal cavity, saline should pass through the needle without resistance and the meniscus should descend down the hub of the needle when the syringe is detached (the so-called drop test); free descent of the meniscus sometimes requires manual elevation of the abdominal wall. The presence of significant resistance in the syringe or failure of the meniscus to descend usually indicates extraperitoneal placement or apposition of the needle against the underlying omentum and usually mandates replacement. Insufflation tubing is then attached to the needle. An initial pressure reading of less than 10 mm Hg further suggests appropriate placement, whereas higher pressures generally indicate extraperitoneal placement. Once satisfactory placement of the needle has been achieved, CO2 is insufflated through the needle to a pressure of 12–15 mm Hg. The needle is then removed and a cannula and sharp trocar are inserted though an appropriately sized skin incision.

A variety of instrumentation has been developed to facilitate the closed approach. This includes expandable sheaths, which are introduced over the needle and can accommodate larger ports which dilate open the fascial opening (or radially expanding trocars), and devices that dilate the fascial opening under direct vision (or optical access trocars). Such instrumentation may also obviate formal fascial closure because the resulting fascial defect is small after removal of the port.

The open approach holds the theoretical advantage of minimizing the potential for injury to intra-abdominal visceral and vascular structures. Disadvantages include the generally longer-associated operative time and the occasional need for larger skin incisions, particularly in obese patients. In contrast, the closed approach is generally faster and may allow better cosmesis. Contraindications to the closed approach include the suspected or known presence of extensive intra-abdominal adhesions and pregnancy. However, in patients who have had limited prior surgery, the closed approach may be used to gain access at a site remote from the previous surgical site. The safety of open and closed approaches has been compared in several studies. A large retrospective review of closed laparoscopy in 489,335 patients and open laparoscopy in 12,444 suggested higher rates of visceral and vascular injury in closed laparoscopy. Rates of visceral and vascular injury were 0.083% and 0.075% after closed laparoscopy, and 0.048% and 0% open laparoscopy, respectively (p = 0.002). Mortality rates after closed and open laparoscopy were not statistically different.14 Notably, this small difference was not evident in several other meta-analyses.15,16

Placement of Additional Ports

The approach to the placement of secondary cannulas is highly surgeon and operation specific. Some basic principles, however, should always be adhered to. These include: (1) all cannulas should be inserted with the aid of laparoscopic visualization; (2) cannulas must be placed far apart from one another to avoid frequent crossing of instruments (generally 10 cm or more apart); and (3) the cannulas should be placed at a distance from the operative site, which maximizes range of motion at the cannula site and minimizes operator discomfort (approximately 15 cm). Additionally, skin incisions, while often small, should never compromise easy passage of trocars through the abdominal fascia. Undue resistance at the level of the skin can undermine the surgeon's control of the trocar as it passes through the peritoneum and lead to injury of underlying viscera or vascular structures.

As noted above, wound complications make a dominant contribution to surgical morbidity. Indeed, wound infection is the most common early complication and incisional hernia is the most common long-term complication of open abdominal surgery. Multiple factors contribute to the incidence of wound failure, including diabetes mellitus, malnutrition, obesity, and corticosteroid use. Surgical technique also appears to influence rates of wound failure; however, there has been little consensus regarding the optimal approach to closure. An evolving literature focuses on the relative merits of multiple-layered versus single-layer closure, closure with different suture materials, and interrupted versus continuous closures.

Closure of the Fascia

The abdomen can be closed in multiple layers or en mass. The former technique reconstructs the anterior and posterior aponeurotic sheaths separately with the posterior layer generally incorporating the peritoneum. Mass closure involves a single-layer closure of all layers and may or may not include the peritoneum. Numerous clinical trials have compared multiple-layered closure to mass abdominal closure. Some studies have shown an increased incidence of dehiscence and incisional hernia formation with multiple-layered closure,17,18 while other studies show no difference in the incidences of these complications.19 Given the shorter time required to close the fascial layers en mass, this method is generally preferred.

The relative advantages of resorbable versus nonresorbable suture for use in closing the fascia have long been debated. Opponents of closure with nonresorbable suture invoke higher rates of suture sinus formation and increased postoperative pain; the incidences of these complications have been estimated at 8% and 17%, respectively. In contrast, it has been suggested that closure with resorbable suture may lead to increased incidences of dehiscence and hernia formation owing to an intrinsic loss of tensile strength during the postoperative period. While these complications are certainly seen with increased frequency when absorbable catgut suture is used,19 the literature has not consistently borne out an association between wound failure and the use of resorbable sutures such as polyglycolic acid (Dexon), polyglactic acid (Vicryl), polydioxanone (PDS), and polyglyconate (Maxon).20–25 In particular, several studies comparing permanent (Prolene, Ethicon, or Nylon) and slowly absorbable suture (PDS and Maxon) have failed to demonstrate any advantage to the use of nonresorbable suture. There may be some advantage to the use of slowly resorbable compared to rapidly resorbable suture; one study demonstrated a significant decrease in the rate of hernia formation when slowly resorbable suture (PDS and Maxon) were used compared to more rapidly resorbable sutures (catgut, Dexon, and Vicryl) (p = 0.009).25,26 Nonresorbable suture does appear to be associated with a higher incidence of suture sinus formation. This association may be greatest with multifilament permanent suture, which may abet bacterial ingrowth and infection.21,24Table 6-1 shows the rates of resorption for different suture materials.

It has been suggested that a continuous, running closure will result in a more durable wound than an interrupted closure. The former may allow the more even distribution of tension across the suture line with less resultant tissue strangulation and wound disruption. The obvious disadvantage of a continuous closure is its dependence on a single suture. The majority of studies comparing interrupted and continuous closure, however, demonstrate similar incidences of wound dehiscence, incisional hernia, wound infection, wound pain, and suture sinus formation.25,27–30 One recent randomized trial compared interrupted and continuous closure with resorbable suture. No significant difference in the rates of incisional hernia, dehiscence, or wound infection was observed.31

In summary, an evidence-based approach to laparotomy closure narrowly favors the use of nonresorbable or slowly resorbable suture in order to minimize the risk of hernia formation. The latter is preferred because of the lower-associated risk of suture sinus formation and decreased postoperative pain. A running closure is associated with either an equivalent or lower risk of hernia formation and, given the ease and speed with which it can be performed, is to be preferred. Importantly, undue tension should not be placed on the running closure to avoid strangulation of the fascia.

Technique of Mass Closure of the Abdomen

When closing a midline laparotomy incision, two size #0 looped or size #1 nonlooped slowly resorbable monofilament sutures are generally used. One suture is anchored at the upper extent and one at the lower extent of the wound. A malleable retractor can be used to protect the underlying viscera while the fascia is closed. The suture is run in a continuous manner, taking full-thickness bites of the linea alba fascia incorporating both the anterior and posterior rectus aponeuroses (Fig. 6-14). Sutures are passed through the fascia a minimum of 1 cm from the wound edge at 1 cm intervals. An assistant holds steady tensions on the suture while the closure progresses. Repetitive relaxation and application of tension of the suture is avoided to limit injury to the fascia. Likewise, it is unnecessary and probably counterproductive to overly tighten the suture as closure progresses, as this may lead to fascial necrosis. This point has been illustrated in a study associating evisceration and hernia formation with a lower suture length to wound length ratio.33 The two sutures are run toward one another and then tied together in the center of the wound.

Skin Closure

A number of skin closure techniques can be used following clean (class I) or clean-contaminated (class II) operations; these include interrupted suture, subcuticular suture, stapled, and adhesive glue. Three randomized-controlled studies have compared stapled to subcuticular suture closures. Both techniques are associated with equivalent rates of wound infection.34–36 Two of the studies suggested that subcuticular suture closure is associated with less postoperative pain than is stapled closure.34,36 Two studies also demonstrated a superior cosmetic result early following suture closure; however, this difference was insignificant by 6 months after operation.35,36

Glues are used with increasing frequency for skin closure. Advantages of glues include ease and rapidity of application and simplification of wound care; generally, no additional dressing is required. Closure with glues has been compared to traditional skin closure methods in several clinical trials. Wound durability appears to be comparable,37,38 although there are conflicting data on cosmesis, and postoperative pain.38,39 If the surgical site is contaminated (class III or class IV wound), the skin should be left open to heal by secondary intention or by delayed primary skin closure.40

Retention Sutures

The incidence of fascial dehiscence after major abdominal operations is 1–3% and is associated with a mortality rate of 15–20%.41 Several patient-related factors are associated with an increased risk of fascial dehiscence, including advanced age, male gender, malnutrition, anemia, and steroids use; however, local mechanical factors and closure technique appear to have a greater influence on the rate of dehiscence.41 Placement of drains or ostomies through the main incision compromises fascial integrity and should be avoided. Wound sepsis and increased intra-abdominal pressure, whether from ileus, bowel obstruction, atelectasis, or after hernia repair, also compromise the integrity of a fascial closure. Indications for prophylactic placement of retention sutures at initial operation remain controversial. The purpose of retention sutures in this setting is to relieve tension along the suture line in order to prevent significant wound disruption and evisceration in the patient at high risk.

There has been only one randomized trial comparing closure with and without retention suture placement. Hubbard and associates could not identify a benefit of retention suture closure over standard mass closure of the abdominal wall.42 The potential disadvantages of retention sutures, however, are well known and include entrapment of underlying viscera, increased postoperative pain, poor cosmesis, and leakage of intraperitoneal fluid through the wound.43 Some surgeons advocate primary closure with retention sutures in selected circumstances. In a retrospective study of midline abdominal wound dehiscence, Makela and colleagues identified preoperative variables that are significantly associated with fascial disruption, including hypoalbuminemia, anemia, malnutrition, chronic pulmonary disease, and emergent operation. For patients with three or more of these preoperative risk factors, this group recommended internal retention suture closure.44

When employed, retention sutures are placed across the wound prior to formal fascial closure. Interrupted permanent monofilament sutures are passed through skin and fascia approximately 2 cm from the wound margin at intervals of several centimeters. Placement is facilitated by the use of a long cutting needle. It may be advantageous to omit the peritoneum from the retention closure in order to protect underlying viscera from injury or entrapment. After conventional closure of the fascia, the sutures are threaded through rubber tubing bolsters or commercially available plastic bolster devices and tied at the skin level.

Mesh and Biologic Implant Placement

Placement of a mesh underlay represents an alternative approach to the prophylactic placement of retention sutures for the at risk abdominal closure.45,46 Additionally, the occasional operation that requires resection of a significant portion of the abdominal wall, as well as transection of bowel, sometimes necessitates the placement of a prosthesis in a potentially contaminated field. Interposition placement of resorbable mesh accepts a hernia that will require complex abdominal wall reconstruction to repair. Moreover, high rates of fistula formation and mesh infection have been described with resorbable as well as nonresorbable mesh in this setting.46 Biologic implants, such as human and porcine acellular dermal allograft, are an attractive alternative to meshes when faced with a difficult-to-close abdominal wall, particularly in the setting of contamination. As with resorbable meshes, underlay rather than interposition placement likely yields a much more durable result. While the use of these products in acute clinical settings has been described,47 there is little definitive data to guide selective application of such techniques. More complex abdominal reconstructions utilizing component separation techniques, releasing incisions or rectus mobilization in conjunction with mesh or biologic implants, may be undertaken in appropriately selected patients when primary closure is not possible. More often, such approaches are utilized in a delayed fashion after development of an abdominal wall hernia.48

Closure of Laparoscopic Incisions

The closure of laparoscopic incisions poses particular challenges. Reapproximation of the fascia is made more challenging in the presence of small skin incisions, which limit visualization. While small fascial defects may be left open, any fascial defect 10 mm or greater in the midline or below the arcuate line should generally be closed to reduce the risk of port-site hernia formation.49 The use of radially expanding trocars obviates the need for formal closure in many cases, although larger midline defects still generally require suture reapproximation.50–52

While sometimes challenging, particularly in obese patients, secure reapproximation of the fascia, usually with several interrupted sutures, can be achieved under direct visualization. Alternatively, a variety of instrumentation may be used to facilitate closure, usually in combination with laparoscopic visualization and maintenance of pneumoperitoneum. The Endoclose device (Tyco Healthcare, Mansfield, Massachusetts) has a sharp tip, which also functions as a grasper. The tip of a suture is grasped with the device and driven through the fascia adjacent to the cannula (and fascial defect) under laparoscopic visualization. The end of the suture is left free inside the abdomen. The grasper is then placed through the fascia a second time on the opposite side of the defect, and the free end of the suture is grasped inside the abdominal cavity and pulled out through the fascia. The suture is then tied to close the defect. The Carter-Thomason System (Inlet Medical, Eden Prairie, Minnesota) additionally includes a needle director, which is inserted through the fascia instead of the cannula, which ensures that adequate fascia is obtained by directing the needle at an appropriate angle, and may expedite closure.53

Temporary Closure of the Abdomen

Despite the frequent misconception that temporary abdominal closure techniques are a recent innovation, such approaches have long been utilized. Pringle reported his experience with temporary packing of hepatic injuries in 1908.54 In 1913, Halsted recommended interposition of a nonadherent layer between the injured liver and packs.55 Such an approach did fall out of favor in the period following the World War II owing to the very highly observed incidences of late hemorrhage and sepsis. However, beginning in 1973 with a report by Lucas and Ledgerwood, a number of investigators suggested the feasibility of utility and temporary abdominal closure, particularly in the setting of massive traumatic injury.56–58 In 1993, Rotondo and Schwab introduced the term “damage control” and outlined a three-phase approach to the management of major abdominal injuries. The first phase consists of rapid control of hemorrhage and contamination followed by temporary abdominal closure; the second phase focuses on the restoration of normal body temperature, correction of coagulopathy, and optimization of ventilation; and the third phase involves removal of abdominal packs, definitive operation, and abdominal closure. In their initial series, Rotondo and Schwab demonstrated a marked survival advantage in patients with major vascular injury and two or more visceral injuries treated using the damage control approach (10 of 13, 77%) compared to those definitively closed at the time of initial operation (1 of 9, 11%) (p < 0.02).59 The applications of this approach have broadened with greater experience. Patients who may benefit from this damage control approach include those at risk of developing abdominal hypertension (eg, hypothermia, coagulopathy, acidosis, large transfusion requirement) and those who require a second-look laparotomy (eg, intestinal ischemia).

This approach has necessitated the evolution of temporary closure techniques. These range from the very simple and inexpensive (eg, towel clip closure, running nylon suture close) to more sophisticated vacuum-assisted closure (VAC) systems. No single approach is clearly superior and multiple techniques may have advantages in specific clinical settings. The Bogota bag utilizes a large IV bag, secured to the skin or fascia. Impermeable plastic drapes may be used alternatively in a similar fashion. This approach is fast, inexpensive, minimizes fluid losses, and is easily removed. It may be less durable than other closures; tearing of sutures through the periphery of the bag can result in evisceration. Absorbable meshes such as polyglactin 910 (Vicryl; Ethicon, Somerville, NJ) and polyglycolic acid (Dexon; Davis & Geck, Danbury, CT) can be sutured to the skin or fascia. This approach allows for a degree of flexibility as definitive closure can subsequently be undertaken without removal of the mesh. Alternatively, the mesh can serve as a bed for the elaboration of granulation tissue. If reapproximation of the fascia is not feasible or needs to be substantially delayed, a skin graft can be placed over the granulation bed. A variation on mesh closure utilizes the Wittman patch, a device made of two adherent sheets of biocompatible polymeric material. The edges of the patch are sewn to the surrounding abdominal fascia. As edema resolves, the fascial edges are gradually reapproximated by drawing the two sheets closer together and cutting away excess material.

An increasingly popular alternative to these temporary closures has been termed the “open abdomen technique.”60 Generally, a nonadherent barrier (eg, a towel covered with an adhesive plastic drape) is placed on top of the intra-abdominal contents, below the fascia. Jackson-Pratt drains are placed above this barrier to control drainage and maintain the integrity of an adhesive dressing placed over the entire wound and skin (Fig. 6-15). This dressing is readily applied, inexpensive, and facilitates multiple re-explorations. Loss of abdominal domain can be limited with the additional placement of lacing across the wound; generally, vessel loops laced through skin staples are placed along the edges of the wound, which can be progressively tightened as intra-abdominal hypertension resolves. Maintenance of the open abdomen may be facilitated with the use of the commercially available abdominal VAC. The abdominal VAC comprises a barrier enveloped in nonadherent plastic, which is placed over the intra-abdominal contents below the fascial edges. A polyurethane sponge is cut to the size of the wound and placed over the barrier. The sponge is then covered with an adherent dressing. A small defect is created in the dressing and suction tubing with an adherent appliance is applied over this defect and attached to a vacuum device. Drainage is drawn out through the sponge through the vacuum tubing and into a vacuum canister. This system is particularly useful when multiple re-explorations are anticipated. Additionally, loss of abdominal domain is minimized by the negative pressure exerted on the dressing. While the use of the abdominal VAC may facilitate a more delayed definitive closure, the risk of injury to underlying viscera and fistula formation does increase with additional dressing changes.61 In the patient who cannot undergo definitive closure after approximately 1 week, transition to a Vicryl mesh closure may be advantageous.

Dressing the Wound

At the conclusion of a procedure, a sterile dressing is typically applied to the wound before removal of the sterile drapes. Theoretically, this dressing prevents bacterial colonization of the wound during the initial 24–48 hours of healing, allowing for epithelialization and the formation of coagulum. Before application of the dressing, excess antiseptic solution should be washed off with sterile saline. In general, the dressing should be secured without the use of excessive tape, which may be irritating to the skin. In most cases, the dressing can be removed within 48 hours of application. This practice is supported by studies from the 1960s documenting that exposure of clean, closed wounds to the atmosphere on postoperative day two, is not associated with an increased incidence of infection.62 In many cases, after closure of a clean wound, no dressing is necessary. Indeed, in a randomized study of patients undergoing either inguinal hernia repair or high saphenous ligation, there was no significant difference in the rate of wound infection whether wounds were immediately exposed, covered with a dry gauze dressing, or covered with an occlusive film dressing.63

A variety of dressing types are used in the management of surgical wounds and may have advantages in some specific clinical settings. A simple dry dressing composed of gauze secured with sparing use of tape is generally sufficient. Wet-to-dry dressings are commonly used to dress open and contaminated wounds; mechanical debridement of the wound results from removal of dried packing material with adherent devitalized tissue. Enzymatic agents (eg, papain/urea [Accuzyme]) may be used in conjunction with wet-to-dry dressings to gently debride fibrinous exudate. In addition, application of broad-spectrum antibacterials (eg, silver sulfadiazine) may limit bacterial colonization and promote wound healing.

Recently, VAC dressings have gained great popularity for the management of open wounds. The VAC dressing has three components: (1) the VAC sponge, which is applied directly to the wound bed; (2) an occlusive dressing, which is applied over the sponge to seal it to the surrounding skin; and (3) a suction pump, which provides regulated negative pressure through the sponge. The VAC dressing has been used extensively in a variety of clinical settings and appears to promote granulation tissue formation and wound contraction. A major advantage of the VAC is the need for fewer dressing changes compared with conventional wet-to-dry dressings. As discussed above, the VAC has become a prominent part of the armamentarium for treating abdominal wounds that cannot be definitively closed at the time of initial operation.

Surgical Site Infections

Surgical site infections (SSIs) are the most common nosocomial infections in surgical patients. It has been estimated that each SSI results in 7.3 additional inpatient days and adds over $3000 to the hospital charges.40 The bacterial colony count at the surgical site makes a dominant contribution to the risk of wound infection; colony counts per gram of tissue of 105 or greater are associated with a marked-increased risk. In the presence of a foreign body, however, a much lower count may lead to infection. Other risk factors for the development of wound infections include advanced age, obesity, diabetes mellitus, smoking, malnutrition, altered immune response, preoperative hospitalization, presence of infection at a remote body site, length of operation, and use of surgical drains.40

SSIs are subdivided into two categories: incisional and organ/space (Table 6-2). Incisional SSIs are limited to the surgical site. They are further divided into superficial SSIs, which involve the skin and subcutaneous tissue and deep SSIs, which involve the fascial and muscle layers. Organ/space SSIs can involve any part of the anatomy that was manipulated during the surgery excepting the incision.

Wounds can be classified by degree of contamination (Table 6-3). The risk of a postoperative SSI reflects, in part, the wound classification; however, infection rates vary widely within each classification group.64,65 Other risk-scoring systems have, therefore, been developed to better anticipate the risk of wound infections. Examples of such scoring systems are the SENIC (Study of the Efficacy of Nosocomial Infection Control) and NNIS (National Nosocomial Infection Surveillance) risk indexes. The SENIC system predicts risk associated with abdominal surgery, operations lasting longer than 2 hours, contaminated or dirty wound classifications, and operation on patients with three or more discharge diagnoses.64 The NNIS system predicts risk associated with American Society of Anesthesiologists preoperative assessment scores of greater than 2, wound classifications of contaminated or dirty, and increased duration of the operation.65

The organisms most commonly responsible for SSIs are Staphylococcus aureus and coagulase-negative staphylococci. After abdominal surgery, infection with enteric organisms (Escherichia coli and Enterobacter species) is also prevalent. The Centers for Disease Control and Prevention recommendations for the prevention of SSIs are summarized in Table 6-4.40 The use of preoperative prophylactic antibiotics in all clean-contaminated and clean cases with associated risk factors is recommended. The antibiotic of choice for most upper gastrointestinal procedures is cefazolin or a comparable first-generation cephalosporin. For colorectal surgery, metronidazole is added to this regimen. The administration of a mechanical and oral antibiotic bowel preparation has been recommended prior to colorectal surgery, although this practice has been challenged by recent meta-analyses suggesting no benefit.66,67 Preoperative intravenous antibiotics should be administered 30–60 minutes before the incision is made to allow the agent to reach maximal tissue concentration. In obese patients, the antibiotic should be adjusted appropriately. For long procedures, the antibiotic should be readministered after every two half-lives to maintain an effective serum concentration.

The treatment for incisional SSIs includes removal of skin stitches or staples to allow drainage of any underlying collection. Antibiotics are indicated in the presence of cellulitis. The effective use of antibiotics depends on (1) appropriate coverage of the offending organisms and (2) maintenance of an adequate tissue concentration of the drug. Cefazolin or an equivalent first- or second-generation cephalosporin is appropriate for uncomplicated incisional SSI. Wound cultures are obtained in the presence of purulence and are used to guide antibiotic selection. Following abscess drainage, wounds are left open and allowed to close by secondary intention.

Deep space SSIs also require drainage. Increasingly, this is achieved by percutaneous placement of a drain under CT or ultrasound guidance. Deep space infections that are not amenable to percutaneous drainage require operative drainage. Broad-spectrum antibiotics are indicated until culture data is obtained at which point the spectrum should be narrowed to target the offending organism.

Necrotizing Wound Infections

Necrotizing soft tissue infections are a heterogeneous group of clinical entities68; however, several fundamental concepts govern the treatment of all. Paramount is early identification followed by operative debridement and initiation of antibiotic therapy. Patients often present early in the postoperative period (ie, within 48 hours) with incisional pain followed by the rapid onset of signs and symptoms of sepsis. While the incision may initially appear benign, more often serous drainage is noted. Patients may also present with bulla or blebs, crepitus, cutaneous anesthesia, and cellulitis that are refractory to antibiotic therapy.69 Tenderness that extends beyond the borders of the apparent cellulitis suggests progression of the infection to the deeper cutaneous layers and should raise suspicion for an early necrotizing process. Importantly, fewer than 40% of patients exhibit the classic symptoms and signs described and a high degree of suspicion should be maintained in the postoperative patient with early signs of sepsis.70,71

In the absence of characteristic clinical features, diagnosis can be challenging. An elevated white blood cell (WBC) count (≤15,400/mm3) and hyponatremia (serum sodium level lower than 135 mmol/L) are sensitive markers for the presence of a necrotizing soft tissue infection; however, they are fairly nonspecific.72 Imaging studies, including plain x-ray and CT, may reveal the presence of soft tissue gas, though this finding is present in a minority of cases.69,73 The reported sensitivity of MRI for diagnosis of necrotizing soft tissue infection ranges from 89% to 100%, and its specificity ranges from 46% to 86%.74,75 However, the frequent presence of subcutaneous air in an early postoperative wound precludes reliable imaging in most cases and, more importantly, imaging may delay appropriate treatment.

In suspected cases, immediate surgical exploration and debridement is recommended and constitutes the most important single therapy. Clostridium perfringens or group A beta-hemolytic streptococci are the most frequently implicated organisms, but necrotizing infections are often polymicrobial. A sample of debrided tissue should be sent for gram stain and culture, and initial therapy should have a broad spectrum of coverage (eg, penicillin, clindamycin, and an aminoglycoside). Following initial debridement, the wound should be reexamined frequently. Any evidence of extension of the necrotizing process should prompt further debridement. Although the initial management of all necrotizing infections is essentially the same, there are several specific clinical entities that deserve special mention, as they may require unique therapies.

Gas Gangrene.

Gas gangrene infection following abdominal surgery results from contamination with clostridia, typically from the alimentary tract or biliary system. Patients usually present with severe wound pain often associated with fever and tachycardia. Such wounds often appear edematous and erythematous; they later become dusky and necrotic. Wound crepitus and foul smelling watery discharge, so-called “dishwater drainage,” are characteristics. Early surgical intervention with debridement of all infected and nonviable tissue is recommended in suspected cases. Although there have been no controlled clinical trials, there is some evidence that hyperbaric oxygen is of considerable value in treating clostridial infection, and reduces the mortality rate by some reports from 66% to 23%.76 The potential benefits of hyperbaric oxygen include improved leukocyte function and increased tissue oxygen levels; it is bactericidal for C. perfringens and bacteriostatic for other anaerobic bacteria.77

Necrotizing Fascitis.

This syndrome has been divided into two subcategories depending on the implicated organisms. Type I necrotizing fasciitis is a polymicrobial process; Type II necrotizing fasciitis is caused by group A streptococci.68,78 Polymicrobial necrotizing infections are generally slowly progressive and affect the total thickness of the skin, but do not involve the deep fascia. Purulence may or may not be present. Most often, such infections are heralded by a nonspecific cellulitis around the wound that slowly extends over days. Later, the central area of the cellulitis becomes purple and then develops typical features of gangrene. These infections are referred to as Fournier's gangrene when they affect the perineum. The causative organisms are usually a mixture of anaerobes, gram-negative rods, and enterococcus species. Broad-spectrum antibiotics should be initiated early and then tailored pending the result of microbial cultures.

Necrotizing infections caused by group A streptococci are more rapidly progressive and can involve the subcutaneous fat, the superficial fascia, and the deep fascia. Early in the process, the overlying skin is often intact, but later may become compromised following interruption of the deep blood supply. The condition is clinically distinguished from gas gangrene by the absence of crepitus and muscle involvement. Early operative exploration is recommended in suspected cases. Group A streptococcus is highly sensitive to penicillin; however, the addition of clindamycin appears to have clinical benefit.78 Treatment must include early surgical exploration with debridement of involved tissues.

Seroma and Hematoma

Superficial seroma formation is exceedingly common but rarely has significant clinical consequence. Most seromas can be observed; the rare large seroma that causes troubling symptoms (eg, discomfort) or is cosmetically unacceptable to the patient can usually be managed with a single aspiration, or serial aspirations in the office. Refractory large seromas can be treated with percutaneous placement of a drain, which is maintained until the output is low (usually less than 30 cc per day) or, rarely, excision (ie, capsulectomy).

The more liberal use of aspirin, plavix, and heparins in the perioperative period has likely resulted in an increased incidence of wound hematoma following abdominal surgery; now in the range of 4–8%.79,80 Small wound hematomas are of little consequence and usually resolve without intervention. If larger, hematomas may lead to compromise of the overlying skin or predispose to infection. Such hematomas can be aspirated with a large-bore needle, or evacuated by opening the wound. If the overlying skin is under tension or ongoing extravasation of blood is noted, hematomas are often better managed in the operating room where active bleeding can be controlled, if encountered.

Stitch Abscess

Stitch abscesses or suture sinuses are most often seen at approximately the 10th postoperative day, but may occur earlier or weeks after operation. Stitch abscesses may be superficial or deep. When superficial, they typically present as brown or mauve-colored circumscribed blisters in the line of the incision. The associated pain can be resolved by incising the overlying skin, evacuating the contents, and, if possible, excising residual suture material. Antibiotic treatment is rarely necessary. Deeper stitch abscesses typically present with an indurated mass. As noted above, the use of nonabsorbable suture, such as polypropylene, has been associated with an increased incidence of deep stitch abscesses when compared to closure with a slowly absorbing suture such as polydioxanone.32,81 When permanent suture has been used, treatment requires removal of the residual suture material.

Wound Dehiscence and Evisceration

Separation of abdominal wounds (ie, dehiscence) with or without protrusion of intraabdominal contents (ie, evisceration) causes considerable morbidity and mortality. Historically, wound dehiscence rates of up to 10% were reported; contemporary series estimate an incidence between 1% and 3%.82,83 Mortality associated with dehiscence has been estimated at 16%.84 The mean time to wound dehiscence is 8–10 days after operation.32,84 Classically, dehiscence is heralded by a sudden rush of pink serosanguinous discharge from the wound. Sometimes, the acute evolution of a large subcutaneous hematoma or tympanitic swelling that distends the wound reflecting herniation of bowel through the abdominal fascia is also noted.

As mentioned above, the literature on abdominal closure appears to favor a running mass closure with slowly resorbable or nonresorbable suture. Notwithstanding such technical considerations, a variety of patient-associated risk factors for dehiscence must be recognized and include advanced age (>65 years), hypoalbuminemia, wound infection, ascites, obesity, steroid use, chronic obstructive pulmonary disease, pneumonia, cerebrovascular accident with residual deficit, anemia (ie, hematocrit <30), prolonged ileus, coughing, emergency operation, and operative time greater than 2.5 hours.44,83,85 Although some surgeons advocate prophylactic placement of retention sutures in those at high risk for dehiscence, there is little data to support this practice.

Fundamentally, the treatment for a disrupted wound is reclosure of the wound; this is particularly true when dehiscence occurs early in the postoperative period. If evisceration is present, the wound and protruding viscera should be bathed with warm normal saline solution and covered with a large sterile dressing prior to prompt transport to the operating room. In the operating room, the prolapsed bowel is replaced below the level of the fascial edges. Residual suture material is extracted, and necrotic wound edges are debrided. Reclosure of the fascia is then performed, typically using a monofilament nonabsorbable suture such as polypropylene. Although some surgeons advocate interrupted closure of the fascia following dehiscence, two retrospective analyses have failed to demonstrate a reduction in the incidence of late ventral hernia formation with this technique compared to a running closure.32,84 The advantage of retention suture placement in this setting is similarly unproven. Retrospective analyses fail to demonstrate any benefit, although a reduction in recurrent evisceration is frequently invoked. Retention sutures are associated with increased discomfort for the patient.43 Placement of resorbable mesh as an underlay may serve to reinforce the abdominal closure.

On occasion, if the dehiscence is small, the patient is critically ill, or there is no evisceration, nonoperative management is appropriate. In such cases, the wound is packed with a moist sterile dressing. An abdominal binder can be used for further support. The dressing should be changed at regular intervals until the wound fills in with granulation tissue. In some cases, delayed reclosure of the skin can be carried out at this stage. Alternatively, the use of a VAC dressing has been described in this setting.86

Incisional Hernia

Incisional hernia formation is the most common long-term complication of abdominal surgery and is discussed extensively in Chapter 7.

Acknowledgements

We would like to thank Bryan M. Burt, Ali Tavakkolizadeh, and Stephen J. Ferzoco for their contribution to the previous edition of this text, which served as the foundation for this revised chapter. We would also like to thank Benjamin Braslow and Bilal Shafi for their valuable suggestions.