The planning, execution, and closure of an incision have an enormous impact on the outcome of an abdominal operation. The high combined incidence of surgical site infection, 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 outcome in ways that defy easy quantification. An incision must provide access to the site of abdominal pathology and allow ready extension if greater exposure 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. While the vertical midline incision remains most popular and is, perhaps, the most versatile, 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 entire 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. Resection of the xiphoid may afford even better superior exposure when needed. 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 4 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 Rocky-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. Retroperitoneal and extraperitoneal structures (eg, the kidney, adrenal gland, and aorta) may be readily exposed through abdominal wall incisions; often obliquely oriented or curvilinear flank incisions are used. Recently, J- or L-shaped incisions have gained popularity for exposure of the upper quadrants of the abdomen and for hepatic resection in particular.

The relative merits and disadvantages of vertical versus transverse incisions remain subjects of active debate. Proponents of transverse incisions argue that they anticipate a more secure closure than with vertical incisions—a hypothesis supported by anatomic and surgical principle. The fascial fibers of the anterior abdominal wall are oriented transversely or obliquely. Transverse incisions, therefore, parallel this orientation and allow for ready reapproximation with sutures placed perpendicular to the 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 to tearing of tissues, resulting in dehiscence or hernia formation. Despite these concerns, little evidence supports a substantial benefit of transverse incisions, and proponents of vertical incisions argue that larger transverse incisions obligate division of muscle fibers with greater functional consequences and leave fewer options for remediation when hernias do develop. 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 However, prospective data have been less definitive. One randomized controlled trial compared vertical and transverse incisions with regard 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

Controversy also 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 adherent to the anterior or 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 have failed to demonstrate an advantage with regard to wound failure rates.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%) and midline incisions (6.9%).⁶

In the patient who has had prior abdominal surgery, the cosmetic advantages of reentering 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 surgical site infection and should, therefore, be avoided. If hair at the surgical site will interfere with accurate wound closure or precludes easy application of the sterile preparation, the use of clippers is preferred to a razor.⁷ A variety of antiseptic solutions are commonly used to prepare the skin, including povidone-iodine, alcohol, and chlorhexidine. The efficacy of povidone-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 surgical site infection when compared to povidone-iodine in a number of studies^8-11 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. 10-1). 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 gentle 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 intra-abdominal organs. In addition, 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 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 2 fingers that are then used to protect the underlying viscera as the peritoneum is further divided along the length of the wound (Fig. 10-2).

Paramedian Incision

Paramedian incisions are vertical incisions placed either to the right or 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 directing the upper portion of the incision along the costal margin toward the xiphoid process (Fig. 10-3). 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. 10-4). 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 ligated when encountered. 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. 10-5).

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 muscle atrophy and 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 allow a more cosmetic closure than do vertical incisions. Importantly, the rectus muscle has a segmental innervation derived from intercostal nerves that enter the rectus sheath laterally. Transverse or slightly oblique incisions through the rectus largely spare these nerves. Provided that the anterior and posterior fascia is closed, the rectus muscle can be divided transversely without significantly compromising the integrity of 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 or left upper quadrant masses. A bilateral subcostal incision provides excellent exposure of the upper abdomen and can be employed for hepatic resections, liver transplantation, total gastrectomy, and anterior access to both adrenal glands.

The standard subcostal incision begins at the midline, 2 fingerbreadths below the xiphoid process, and is extended laterally and inferiorly, parallel to the costal margin (Fig. 10-6). The incision should not be placed too far superiorly because 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 1894,¹² 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. 10-7).

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. 10-8). 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. 10-9). 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. 10-10A). 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. 10-10B). 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.¹³

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 2 layers using nonresorbable sutures. Pericostal sutures are placed to reapproximate the ribs. The chest muscles and abdominal wall are then closed in layers.

L- AND J-SHAPED INCISIONS

L- or J-shaped incisions were first described by Masatoshi Makuuchi and have gained considerable popularity for upper abdominal surgery and liver resection in particular.¹⁴ These incisions, which extend from xiphoid to the umbilicus and across the right or left hemirectus in transverse fashion, have several theoretical and real advantages. Transverse division of the rectus muscle preserves segmental innervation and may minimized postoperative muscle atrophy. Moreover, by combining vertical and transverse components, an abdominal wall flap is created that can be retracted superiorly yielding wide exposure without division of both sides of the rectus. Optimal exposure requires appropriate placement of retractors; use of a retractor system that can be contoured to the incision (eg, the Thompson retractor system, Thompson Surgical Instruments [Traverse City, MI], or other table-based self-retaining systems) is helpful in this regard (Fig. 10-11). Appropriate alignment of the closure is facilitated by initial placement of interrupted sutures at the edge of the rectus muscle, junction of the transverse and vertical portions of the incision, and superior aspect of the vertical incision. Running closure of the fascial layers can then be undertaken. The interrupted sutures are tied prior to skin closure and reinforce the running closure.

RETROPERITONEAL AND EXTRAPERITONEAL INCISIONS

Retroperitoneal and extraperitoneal approaches to the abdomen have several advantages over transperitoneal exposures. Manipulation and retraction of intra-abdominal viscera are limited, and the risk of 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, and 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 to 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 to 14 cm (Fig. 10-12). 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 3 fingerbreadths lateral to the mid-line and carried inferiorly and laterally toward the iliac crest, ending approximately 4 fingerbreadths lateral to the midline (Fig. 10-13). 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 is inadvertently injured, the resulting pneumothorax is handled at closure by insertion of a large-bore rubber catheter into the pleural cavity that 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. 10-14). 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 operations in which a larger incision is necessary to remove the surgical specimen (eg, laparoscopic colectomy) and more complex procedures.¹⁵ 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 (CO₂) is insufflated into the abdomen to a pressure of 12 to 15 mm Hg.