Abdominal Closure

Surgical access to the abdomen is required for many operative procedures, with approximately 4 million open abdominal surgeries occurring annually in the United States.[1]  Guidelines for the management of the open abdomen in the surgical setting have been published by a number of authorities, including the World Society for Emergency Surgery (WSES),[2, 3] the Eastern Association for the Study of Trauma (EAST),[4] the Western Trauma Association (WTA),[5] and the European Hernia Sociwety (EHS).[6]

The measures used to close the abdomen may vary from physician to physician, depending on training, circumstance, and comfort level. However, basic principles govern all abdominal closures. This article outlines these principles.

Indications for abdominal closure include the following:

• Surgery on the abdominal cavity
• Trauma

The main contraindication is abdominal compartment syndrome. Guidelines for addressing abdominal compartment syndrome have been published by the World Society of the Abdominal Compartment Syndrome (WSACS)[7] and others.[8]

Anatomy

The anterior abdominal wall is clearly defined by anatomic borders.[9] The superior border is marked by the costal margins, whereas the inferior border is the pubic symphysis (see the image below).[10]

The abdominal wall is composed of distinct tissue types that must be taken into consideration in closing the surgical abdomen. Generally, the anatomic layers of the abdominal wall (from superficial to deep) are as follows.

The most superficial component of the abdominal wall, the skin (the largest human organ), is composed of the following three layers:

• The epidermis, which provides waterproofing and serves as a barrier to the environment
• The dermis, from which the appendages of the skin originate (e.g. mammary glands)
• The hypodermis, which contains the subcutaneous adipose layer.

For a fuller description, see Skin Anatomy.

Next is the superficial fascia, in which the fasciae and ligaments of the anterior abdominal wall are organized into the following two layers:

• A thin, fatty superficial layer (tela subcutanea), referred to as the Camper fascia
• A membranous or fibrous deep layer, referred to as the Scarpa fascia

The superficial layer of the superficial fascia (ie, Camper fascia) continues over the inguinal ligament to merge with the superficial fascia of the thigh and continues over the pubis and perineum as the superficial layer of the superficial perineal fascia.

The deep layer of the superficial fascia (ie, Scarpa fascia) is attached to the fascia lata just below the inguinal ligament. It continues over the pubis and perineum as the membranous layer (Colles fascia) of the superficial perineal fascia and continues over the penis as the superficial fascia of the penis and over the scrotum as the dartos fascia (tunica dartos), which contains smooth muscle.

The innermost component of the anterior abdominal wall comprises muscle and deep fascia, including the following:

• External oblique muscle
• Internal oblique muscle
• Rectus abdominis
• Transversus abdominis
• Pyramidalis
• Fascia transversalis
• Peritoneum

However, the presence or absence of various layers is location-dependent (see the image below).[11]

The anatomic planes of the abdominal wall are made up of multiple muscular and fascial layers that interdigitate and unite to form a sturdy, protective musculofascial layer that protects the visceral organs and provides strength and stability to the body's trunk. This anatomy varies with respect to the different topographic regions of the abdomen; thus, a firm understanding of these layers, their blood supply, and their innervation is essential to surgical management of the abdomen. (See Regions and Planes of the Abdomen.)

Complication prevention

Correct patient preparation, adherence to sterile technique, and the general principles of closure are outlined below. Known risk factors for abdominal wall dehiscence and hernia formation include the following[12, 13, 14] :

• Wound infection
• Obesity
• Advanced age
• Jaundice
• Postoperative pulmonary complications
• Emergency surgery
• Immune suppression
• Reoperation through previous incision
• Ascites
• Abdominal distention
• Malnutrition
• Cancer
• Multiple comorbidities
• Irradiated wound bed
• Chemotherapy

Drains and ostomies should not be brought out through the main abdominal incision, because they tend to weaken it and may predispose the wound to infection and sepsis.[11]

Equipment required for abdominal closure includes the following:

• Suture
• Staples
• Kocher clamps
• Malleable retractor
• Adhesive tape
• Synthetic glue

Suture selection is highly physician-dependent. Potential advantages and disadvantages are inherent with each particular suture. Suture can be chosen on the basis of tensile strength, longevity, and size. For abdominal closures, significant benefit has been shown for the use of nonabsorbable or delayed-absorbable suture.

Nonabsorbable suture is a prominent choice because it retains its tensile strength; however, it has been reported to yield increased incisional pain.[15] This has led many surgeons to opt for delayed-absorbable suture, which can retain its original tensile strength for some time and has been reported to yield decreased suture pain.[16, 11] The suture length should be at least four times the length of the incision, ensuring that enough suture is available for adequate bites of fascia and that the stitches are not placed too far apart.[12, 10]

Patients should be under general anesthesia. They are generally positioned supine; however, in some instances, it may be important to position them laterally.

A midline incision (see the image below) is the most commonly used route of access to the abdominal cavity[1] ; for this reason, the ensuing discussion of abdominal closure focuses on this incision. The general technique can be applied to other abdominal incisions (some of which are discussed more briefly below); however, it must be kept in mind that the actual layers composing the abdominal wall vary, depending on the location of the incision.

Peritoneal closure

A number of randomized, controlled trials have showed no benefit to peritoneal closure; thus, refraining from closing the peritoneum is a commonly accepted practice.[17] Some surgeons believe that closure of the peritoneum reduces adhesions between the abdominal contents and the suture line; however, at this time, there is only limited scientific evidence for this belief.

Fascial closure

The technique of fascial closure is highly variable among surgeons; however, the various approaches may be grouped into two primary methods as follows[1] :

• Layered closure
• Mass closure

Layered closure is sequential closure of each fascial layer individually. The primary advantage of this method is that multiple suture strands exist, so that if a suture breaks, the incision is held intact by the remaining sutures.

Mass closure is continuous fascial closure with a single suture. This method allows even distribution of tension across the entire length of the suture, resulting in minimization of tissue strangulation. The goal is approximation of tissue edges to allow scar formation. Excessive tension leads to tissue necrosis and eventual failure of the closure.[12]

The theoretical disadvantage of mass closure is that a single suture is responsible for maintaining the integrity of the closure. The benefits of mass closure include decreased cost and decreased operating time. There is no evidence that mass closure is associated with an increased incidence of hernia formation or wound dehiscence.[18]

Numerous trials and meta-analyses found continuous mass closure to be the superior closure method.[1, 19, 20, 21] In the INSECT trial, which compared three methods of abdominal wall closure in 625 patients, Seiler et al found no significant benefit related to any specific closure method.[22] The results of this study underscore the necessity of carrying out further randomized, controlled trials to facilitate the development of a consensus on the best method of abdominal closure. 

The small-bite technique (in which the distance between the suture and the wound edge is reduced to 5-8 mm and the distance from stitch to stitch is reduced to 5 mm from the fascial edge) has been assessed in an experimental study[23] and in a controlled clinical randomized trial.[14] The authors theorized that this approach would reduce tissue trauma and infection, as well as reduce hernia rates. At 4 days after closure of a midline laparotomy incision (with a suture length–to–wound length ratio of 4), the incisional wound burst strength was higher with sutures placed 3-6 mm from the wound edge than with those at 1 cm. Incisional burst strength also increased with the number of stitches used.

In a subsequent systematic review assessing the efficacy of closure techniques, which included 23 randomized controlled trials (nine involving the use of prophylactic mesh), the authors noted that in elective midline closure, the use of a slowly absorbable suture material for continuous closure with the small-bite technique resulted in significantly less incisional hernias than a large-bite technique did.[24] The use of prophylactic mesh in high-risk patients, in comparison with primary suture closure of the midline incision, yielded a significant reduction in the incisional hernia rate.

In continuous fascial closure, two Kocher clamps are clamped to the fascial layer midway through the incision and then retracted by the assistant. Often, having the assistant cross the Kochers allows for better visualization for the surgeon. Suture material is chosen. For most closures, the authors prefer to use looped 0 polydioxanone (PDS) suture.

Starting at the superior or inferior aspect of the incision, the looped PDS is passed through the vertex of the fascia (see the image below). The needle is then passed through the loop locking the stitch in order to anchor the knot or tied if it is not a looped suture. The suture is subsequently run in a continuous fashion, with each bite including tissue from the linea alba, the rectus sheath, and muscle itself if necessary to get an adequate bite.

When rectus muscle is incorporated, using absorbable suture and a loose closure in order to decrease postoperative pain and tissue necrosis is important. The assistant following the continuous closure should apply sufficient tension to approximate the tissue without strangulating it. Suture is run in 1-cm intervals (maximally), with at least a 1-cm bite of fascia in each throw.

A malleable retractor can be placed under the suture line to ensure that the underlying structures are not incorporated into the closure. When the center of the incision has been reached, the same method is used on the opposite end of the incision. When the two ends are within 1 cm of each other, they are tied with six to 10 knots.[14, 25, 11, 10]

Subcutaneous closure

The vascular supply to the subcutaneous tissue of the abdominal wall is limited, increasing susceptibility to soft-tissue infection.[11] The purpose of subcutaneous closure is to close any potential space, reducing the area for seroma accumulation.

Although in theory this may stand, a paucity of data exists regarding the significance of closing the subcutaneous fat. Only one prospective randomized controlled trial has been conducted to determine the value of this practice, and the authors found no significant differences in complications between closure and nonclosure.[26] Subcutaneous closure may be accomplished with absorbable suture in an interrupted or continuous fashion.

Skin closure

The skin can be closed using various methods[1] ; however, a few consensus techniques are generally used. The two primary methods of skin closure are with suture or staples. Suture closure is generally performed with 3-0 or 4-0 absorbable suture in a running subcuticular fashion or with nylon running or interrupted transdermal suture. Staple closure is a viable alternative to suturing the skin. In a study comparing scar cosmesis at 6 months, no difference in appearance existed in patients with suture versus staple skin closure.[27, 28]

Finally, class III (contaminated) and IV (dirty) wounds should not be closed and should be left open to heal by secondary intention,[12, 29] with the possibility of delayed primary closure, depending on the state of the wound bed as it progresses. Adhesive tapes and synthetic glues can be used in addition to sutures and staples to reinforce closure.

Paramedian incision

Paramedian closure is similar in technique to midline closure; however, it is necessary to ensure reapproximation of the anterior and posterior rectus sheath when above the arcuate line (see the image below).

Transverse incision

A transverse incision traverses the anterior and posterior rectus sheath when above the arcuate line; thus, it is necessary to repair both, together or separately. Transverse incisions are felt to have more intrinsic strength than their vertical counterparts because the abdominal fascia fibers are transversely oriented, causing sutures to be placed perpendicular to the fiber direction (see the image below).[30, 31, 11]  Incisional hernia is two to five times more common in vertical incisions than in transverse incisions.[32, 33]

Kocher subcostal incision

Closure of a Kocher subcostal incision requires closure of the anterior and posterior rectus sheaths. This can be accomplished as either a layered or a mass closure (see the image below).

Rockey-Davis muscle-splitting incision

With a Rockey-Davis incision, some benefit to closing the peritoneum has been shown.[11]  Continuous absorbable suture may be used. The internal oblique and transversalis muscles should be subsequently closed in a single layer with interrupted or running suture. The external oblique aponeurosis is then closed with an interrupted or continuous absorbable suture (see the image below).

Pfannenstiel incision

The Pfannenstiel incision is a transverse suprapubic incision, placed approximately 5 cm superior to the pubic symphysis (see the image below).

Prevention of incisional dehiscence and fascial closure in emergency laparotomy

Between 2009 and 2013, an estimated 2 million patients per year underwent an open surgical intervention in the United States.[34] A number of these procedures were complicated by fascial dehiscence, with concomitant increases in costs, hospital length of stay, additional interventions, and associated complications.

Abdominal fascial wound dehiscence may manifest as a partial or total separation of previously approximated wound edges. This is most often due to a failure of proper wound healing. Wound dehiscence more commonly occurs in the first 1-2 weeks following definitive fascial closure of the abdominal wall, during the early stages of tissue healing.[35]  The causes of dehiscence and poor wound healing include ischemia, infection, increased abdominal pressure, diabetes, malnutrition, smoking, and obesity.[36]

In the past, abdominal midline surgical wound dehiscence rates as high as 10% were reported[37] ; more recently reported figures have been in the range of 1-3%.[38, 39]  Emergency trauma laparotomies have a higher rate of fascial dehiscence (5-50%) than elective laparotomies (5-10%).[40, 41, 42, 43]  Damage-control surgery (trauma or emergency general surgery) is associated with fascial dehiscence rates of 13-50%.[43]  Mortality in patients with midline abdominal surgical wound dehiscence ranges from 10% to 30%.[43]   

There continues to be debate regarding the most effective strategy for abdominal-wall closure. The data seem to suggest that there is no difference between continuous and interrupted fascial closure in elective cases.[20, 44, 45]  However, most of the published studies have not focused on patients who undergo emergency laparotomy. 

In a 2008 meta-analysis (23 studies; N = 10,900) Gupta et al compared continuous and interrupted techniques in abdominal wound repair,[46]  with abdominal wound dehiscence (burst abdomen) and incisional hernia as the primary outcomes. Interrupted closure was associated with significantly less dehiscence than continuous closure, and no differences were found between the two methods with regard to hernia risk. The authors' analysis led them to conclude that the particular technique used for interrupted suturing is critically important to the outcome. They recommended that either a figure-eight or a double horizontal mattress technique be employed to yield a secure repair.

In a randomized controlled trial from 2014, Agrawal et al found that intraperitoneal sepsis, persistent cough, uremia, wound infection, and necrosis of the linea alba were significant predictors of fascial dehiscence.[47]  They also noted that using interrupted sutures for closure of laparotomy incisions in this setting reduced the risk of abdominal wound dehiscence to less than 33%.

In a randomized controlled trial from 2019, conducted on 300 consecutive patients undergoing emergency midline laparotomy, Bansiwal et al found that patients whose laparotomies were closed by suturing the rectus sheath with 1-0 polydioxanone in a continuous layer had a significantly higher rate of burst abdomen (20.1%) than those whose laparotomies were closed with 1-0 polydioxanone in an interrupted layer (5.4%).[48]  The authors concluded that interrupted closure of abdominal-wall fascia was better than continuous closure in the setting of emergency laparotomy.

In a randomized controlled trial from 2020 (N = 80), Sharma et al evaluated the efficacy and safety of two commonly applied abdominal-wall closure strategies—continuous suture (group A; n = 40) and interrupted X suture (group B; n = 40)—in gynecologic patients undergoing primary emergency midline laparotomy.[49] The aim of the study was to assess the incidence of wound infection and wound dehiscence. Wound infection occurred in 12 group A patients and 10 group B patients, whereas wound dehiscence occurred in two group A patients and no group B patients. Incisional hernia did not occur in either group.

A review of the current literature addressing the techniques used in emergency laparotomy fascial closure appears to suggest that the interrupted suture method may offer some benefit in decreasing the incidence of early postoperative wound dehiscence. This is an evolving field of study, and additional research will be required for further refinement of these initial recommendations. 

Retention closure

Guidelines for the prophylactic use of retention sutures are imprecise at best. The only controlled study that was performed showed no positive effect in the use of prophylactic retention sutures; in fact, patients receiving retention sutures had a greater amount of postoperative pain.[50, 51]  Nevertheless, these sutures may be useful and are often used in the following patients[25, 50] :

• Those with increased tension on the incision
• Those who are severely malnourished
• Those who are immunocompromised
• Those with previous fascial defect
• Those with massive contamination

Retention sutures are placed outside of the primary suture line through all layers of the abdominal wall, including the skin; a large-bore suture material, usually nonabsorbable, is employed. The effect is to alleviate the tension on the primary suture line. Various bridges, bumps, and bolsters are available to alleviate some of the tension the retention suture places on the skin surface. These sutures should be removed as soon as the danger of increased abdominal pressure has passed.

General recommendations

In the author's opinion, there appears to be no additional benefit in the closure of the peritoneum.[52]

For elective surgical procedures, a continuous mass closure, using a slowly absorbable suture placed with minimal tension that will provide sufficient strength to the wound (eg, #1/0.400-0.499 mm diameter) while minimizing foreign body reactions, is preferred. Multifilament sutures have better knot strength; however, they have a higher incidence of infection, hernia, and sinus formation.[20, 19, 53]  Most abdominal incisions can be closed with a one-half or five-eighths circle, taper point, and general closure needles. If the fascia is very thick,a hernia needle may be required.

The optimal closure technique in the emergency setting has not been defined. The author prefers an interrupted technique in this setting. The interrupted closure has the advantage of not depending on a single knot; however, if it is not applied properly, it may give rise to tissue ischemia as a consequence of uneven distribution of tension throughout the incision.[54]

Skin staples, subcuticular sutures, surgical tape, tissue adhesives, or some combination thereof may be used, and the closed incision may  be covered with a semipermeable film or hydrocolloid dressing. Reports have suggested that the use of closed incision negative pressure therapy (ciNPT) dressing systems may significantly decrease postoperative superficial and deep wound infections in high-risk patients after open mesh repair of ventral hernia. These ciNPT wound dressings have been found to be cost-effective in high-risk operative patient populations.[55, 56]

Temporary abdominal closure

Occasionally, circumstances may dictate that permanent closure of the abdomen is contraindicated. Examples of such circumstances include the following:

• Early planned reexploration of the peritoneal cavity
• Unacceptable abdominal wall tension with conventional closure
• Increased intra-abdominal pressure
• Intraoperative instability necessitating a rapid temporary closure

Various methods and materials are used to accomplish temporary closure (eg, sterile intravenous bag, fish-shaped viscera retainer, or abdominal vacuum pack). Evidence-based recommendations have been developed for the use of negative-pressure wound therapy (NPWT) in the setting of the open abdomen.[57]  Some have reported good results with the use of expanded polytetrafluoroethylene (ePTFE) mesh for temporary abdominal closure in critically ill nontrauma patients.[58]

Regardless of the method used for temporary abdominal closure, the primary aims must be to protect the abdominal viscera and to maintain sterility. (For more information, see Temporary Abdominal Closure Techniques.)

Staple or suture removal should occur at approximately 7-14 days. Sterile dressings applied during surgery are generally removed on the second to seventh postoperative day per surgeon preference. Saturated dressings should be changed when noted.

Patients should be cautioned to avoid lifting, pushing, or pulling anything heavier than 10 lb (~4.5 kg) and generally to avoid any type of straining (increased abdominal pressure) as much as possible for 4-6 weeks after surgery. They should be educated on signs and symptoms of incisional hernia and should be encouraged to contact the surgeon postoperatively in the presence of any of the following (any of which may portend postoperative complications):

• Purulent drainage
• Protracted serosanguineous drainage
• Erythema
• Uncontrolled pain
• Bulging at the incision
• Protracted nausea or vomiting

Short-term complications include wound infection and dehiscence. The most commonly documented postoperative complication is incisional hernia, which occurs in approximately 9-20% of patients after an abdominal closure.[1, 22, 59] Long-term monitoring after the postoperative period is not considered necessary.