Omental (Graham) Patch 

Introduction

Omental patching began in 1937, when Dr. Graham of Toronto reported 51 cases of perforated peptic ulcer successfully treated with an omental patch.^[1] In Dr. Graham’s initial cases, he concluded that routine gastro-enterostomy was unnecessary, the omental patch being more than sufficient for closure of the duodenal perforation. More than 70 years since its initial description, this technique is still extremely useful in selected patients with perforated duodenal ulcers.

Indications

The goal of an operative procedure for perforated duodenal ulcers is to provide durable repair of the injury with appropriate source control and limitation of parietal cell acid production. Control over gastric acidity has been traditionally gained using vagotomy and drainage or parietal cell vagotomy. However, since the introduction of proton pump inhibitors, chemical vagotomy has decreased the rate of surgical vagotomy because of the high efficiency of proton pump inhibitors in preventing acid production with relative ease.

The discovery that most ulcers can be treated by eradication of Helicobacter pylori has further fueled the move toward minimalist damage-control omental patching in this setting. The modern operative approach to a perforated duodenal ulcer can include omental patch alone with postoperative use of proton pump inhibitors and eradication of H pylori, as indicated; or it can include an omental patch with surgical control of gastric acid by vagotomy and drainage, parietal cell vagotomy, or antrectomy. The choice of operation is dictated by the pathology responsible for the perforation, the patient’s premorbid health status, the patient’s perioperative hemodynamic status, and the degree of contamination of the peritoneum that has been found.

In circumstances of generalized peritonitis, hemodynamic instability with shock, perforation for more than 24 hours, perforation clearly associated with NSAID use, or if the patient has not had significant symptoms for 3 months before the procedure, the omental patch alone is indicated. Addition of parietal cell vagotomy or vagotomy and drainage can be performed in a certain population of patients as delineated below. Nevertheless, most patients respond well to postoperative treatment of H pylori and chemical vagotomy with proton pump inhibitors; mortality, morbidity, and ulcer recurrence with omental patch repair have all been shown to be extremely low.^{[2, 3]}

Many speculate that the balance will shift further away from definitive anti-acid surgical intervention in the future because fewer and fewer vagotomies are being performed, and the newest surgical trainees, therefore, have less experience in performing these procedures than did the previous surgical generation. Whether or not the recent demonstration that long-term proton pump inhibitor use is associated with an increased incidence of hip fractures in the elderly skews this balance in the opposite direction remains to be seen.

Omental patch repair has also been incorporated in the management of perforated gastric ulcers. Perforated prepyloric or pyloric ulcers are amenable to closure with omental patch with minimal tension due to the close proximity of the injury. Gastric ulcers in atypical locations (more proximal) or with features suggestive of malignancy should not be patched but wedge-resected unless biopsy and other measures can assure that they are benign. The conservative approach of omental patch repair seems attractive, especially when extensive inflammatory reaction of the pylorus and duodenum is observed, the patient has a poor hemodynamic status, and rapid control of the septic source is required.

Noticed with a frequency of 15%, gastric outlet obstruction is a recognized postoperative complication of patched pyloric or prepyloric ulcers.^[4] If the ulcer is large and the patient is stable, this complication can be prevented by excision of the ulcer and incorporation of the repair into a Heinecke-Mikulicz pyloroplasty. Another indication for this type of repair is in duodenal defects larger than 1 cm in size to allow for prevention of stricture and subsequent obstruction. In clinically stable patients, distal gastrectomy or antrectomy and vagotomy are more aggressive but more definitive surgical options.

Relative indications for adding surgical acid control to an omental patch are as follows:

• Hemodynamic stability (localized peritonitis and minimal spillage of gastroduodenal contents)
• Short duration of preoperative acute symptoms (< 12-24 hours)
• Failure of medical therapy
• Noncompliance with medical therapy
• Need for postoperative NSAIDs
• H pylori negative testing
• Chronic history of peptic ulcer

Resuscitation, anesthesia, and preoperative preparations

Resuscitation of the patient plays a crucial role in the management of a patient with perforated duodenal ulcer. An increase in preload with reduction of the afterload and improvement of stroke output is ideal. This also allows the patient to compensate for the reduction in preload engendered by positive pressure ventilation during and often after surgery. Resuscitation is usually facilitated by using a central venous catheter to measure central venous pressure. This allows the surgeon to resuscitate the patient more aggressively toward a prechosen central venous pressure goal. Monitoring of urinary output and lactic acid also provides important insights into the preoperative resuscitation of a hemodynamically labile patient.

Consideration should be given to placement of an arterial catheter for hemodynamic monitoring and prompt arterial blood gases measurements based upon the degree of shock present. This can be established preoperatively during fluid resuscitation or by the anesthesia team after induction to allow a timely surgical intervention. Resuscitation should be expeditious because a delay in operation is associated with increased morbidity and mortality.

Preoperative decompression of the stomach using a nasogastric tube limits further spillage of gastrointestinal secretions into the peritoneum during the resuscitation period. Broad-spectrum antibiotic coverage is initiated preoperatively and continued postoperatively for a duration dependent on the patient’s clinical status and the degree of intra-abdominal spillage. General anesthesia is used for either open or laparoscopic omental patch repair of perforated duodenal ulcer.

Standard technique

After the patient is placed in supine position on the operating table, the abdomen is prepped and draped in a standard fashion. Transverse epigastric or subcostal incisions have been described. However, an upper midline incision is the preferred route to enter the peritoneal cavity in this setting. In addition to providing good surgical exposure, an upper midline incision also permits extension inferiorly if a perforated ulcer is not found and the remainder of the bowel needs to be inspected and/or manipulated.

Suctioning of the gastrointestinal spillage and of any fibrinous exudates is quickly performed and the attention is turned to inspection of the duodenum and visualization of the perforation. This can be usually found on the anterior wall of the duodenum, in proximity to the duodenal bulb. If the perforation is not apparent, mobilization of the duodenum along with inspection of the stomach and jejunum should be achieved next.

After the bowel perforation was identified, sponges can be used to flank the duodenum to prevent further spillage of gastroduodenal contents. Materials commonly used for repair are nonabsorbable sutures like silk or monofilament absorbable sutures like polydioxanone. The suture can be either a 2-0 or 3-0 on a small half-circle swaged needle.

In the original description of the technique, the full-thickness bites were placed approximately 0.5 cm away from the edges of the perforation from one margin to the other. A theoretical hazard with the full-thickness bites is passing the needle through the posterior duodenal wall. Commonly, 3-4 sutures are placed perpendicularly between the edges of the perforation and are laid out on each side of the duodenum (see the image below).

A patch of omentum is brought without tension and positioned over the perforation, and the sutures are successively tied from the superior to the inferior aspect across the omental patch to anchor the omental graft in place (see the images below)

An important feature of a sturdy repair is reliant on the tying technique. The applied tension to the sutures should be strong enough to stabilize the omentum in place but loose enough to preserve the omental blood supply. Strangulation of the omental patch due to increased tension on the knots is associated with a failure of the repair and continued postoperative leakage. In the classical repair, the sutures are not passed through the omentum but only tied around it. Another variation is to use seromuscular sutures rather than full-thickness bites on the duodenum.

After surgical repair has been accomplished, some surgeons have described performing a leak test to allow detection of technical errors. This can be accomplished either with endoscopic insufflation of air or instillation of methylene blue proximal to the perforation with manual distal compression of the duodenum. However, others argue that this is unnecessary since the repair need not be initially completely occlusive against hydrostatic pressure. These surgeons argue that the goal of the repair is to secure the omentum across the perforation, allowing it to subsequently adhere to the inflamed serosa and thus seal the perforation.

The peritoneal cavity is then irrigated with 10 liters of warm saline solution to remove further contamination. Particular care is taken to irrigate the suprahepatic and infrahepatic recesses, the lesser sac, the paracolic gutters, and pelvis. Optionally, drainage of the areas close to the perforation can be attempted if a concern about possible leakage from the ulceration exists. For this purpose, a Jackson-Pratt drain is sometimes placed in the paraduodenal area or infrahepatic space. The purported advantages of such drainage include the early detection of a postoperative leak and provision of controlled drainage using the closed suction drain if a leak does occur. However, drainage should be selective because routine placement of drains has been found to be associated with significant morbidity and infection with no changes in incidence of postoperative intra-abdominal abscesses.^[5]

The abdomen is then closed in usual fashion with running or interrupted sutures of polypropylene or polydioxanone. If substantial edema of the bowel causes tension on the fascial edges upon attempted closure, then the abdomen may be managed open by various techniques, including a vacuum-assisted closure, the Wittmann patch, or other options.

Technique variations

One variation of the classical technique used by some surgeons is the modified omental patch. After sutures are placed between the edges of the perforation in a standard fashion, they are tied in an attempt to close the wall defect. Without cutting the sutures, a segment of omentum is then brought on top of the closed perforation and tied knots and the same sutures are used to tie down the omental patch over the already approximated perforation.

Opponents of this modified technique express concern regarding the seal obtained from the omentum when suture knots are interposed between the duodenal serosa and the omental patch. At the same time, the apposition of omentum is not as broad as with the original omental patch. However, no definitive conclusions can be drawn from literature regarding the differences in morbidity or mortality associated with each of these techniques.

Another variation of the standard technique is the use of sero-muscular suture placement (Lembert) instead of full-thickness bites. This is accomplished without entering the duodenal lumen, and these sutures theoretically have a lower risk of passing the needle through the posterior wall, minimizing the risk of obstruction. Seromuscular sutures are generally used during laparoscopic repair of perforated duodenal ulcers.

In patients in whom the omentum is not available because of previous surgery, necrosis, or anatomy, a variant technique is that of the Thal patch, in which a loop of jejunum is used to patch the perforation (see the image below). In this case, seromuscular sutures are used to attach the serosal side of a loop of jejunum across the ulcer defect.

Minimally invasive repair

Laparoscopic omental patch closure of perforated duodenal ulcer has become increasingly more common as the field of minimally invasive surgery grows. Initial reports demonstrated little difference between the laparoscopy and the laparotomy approach. Some more recently published papers have in fact suggested that selected patients approached by laparoscopy exhibit shorter length of stay, less postoperative pain, and earlier return to daily activities.^{[6, 7, 8]}

Selection of the patient plays an important role in the success of a laparoscopic technique. Delayed presentation for more than 24 hours, hemodynamic instability, high acute physiology, or chronic health evaluation scores are each associated with significantly increased likelihoods of postoperative leak, and laparotomy is therefore indicated in such patients.^[9] In addition, skill in laparoscopic technique is also required for such procedures. Some surgeons perform intraoperative esophagoduodenoscopy to aid in identification of the perforation and stabilization of the omental patch until laparoscopic suturing can be performed.^[10] The need for intraoperative esophagoduodenoscopy is dictated by the experience of the laparoscopic surgeon and difficulty of the case.

At present, both open and laparoscopic approaches to omentopexy remain within the standard of care depending upon the experience of the surgeon and the condition of the patient.

Postoperative resuscitation

The resuscitation that began in the early preoperative phase is now continued with the use of crystalloid solutions. The goals of resuscitation focus on urinary output, lactic acid levels, mean arterial pressure, and central venous pressure parameters. Vasopressors may sometimes also be required, depending upon the patient’s hemodynamic status and response to resuscitative intervention.

Postoperative nutrition

Many patients requiring this type of repair were malnourished before their perforation. Others become malnourished during a prolonged postoperative septic and catabolic state. Attention to nutrition is therefore important. Healing of the duodenal perforation or operative incision needs to be augmented by an improved nutritional status in the early postoperative period.

Oral feeding is likely to be delayed because of the need for the ileus to resolve and the omental patch to heal. Some patients may benefit from intraoperative placement of a jejunostomy feeding tube. This needs to be particularly considered in elderly or debilitated patients who are expected to have a prolonged hospitalization and deprivation of oral nutrition.

The disadvantages associated with adjunctive surgical jejunostomy feeding tubes include prolongation of the operative case as well as the complications of jejunostomy including leaks, obstruction, and internal herniation. Many patients requiring omental patch are initially hemodynamically unstable and an approach with minimal intraoperative time under general anesthesia is often preferred. An alternative to jejunostomy feeding is intraoperative or postoperative placement of a double lumen gastro-jejunal tube to allow, at the same time, decompression of the stomach and delivery of enteric nutrients distally to the omental patch repair. Parenteral nutrition is sometimes alternatively used, but, generally, enteral nutrition distal to the perforation would be preferable if possible.

Postoperative antimicrobial therapy

Duodenal perforation with localized or generalized peritonitis and spillage of enteric contents in hemodynamically unstable patients found in sepsis or septic shock is considered a complicated intra-abdominal infection. According to the Infectious Guidelines of the Disease Society of America and Surgical Infection Society, antimicrobial therapy should be continued postoperatively for 24 hours when the perforation has been surgically closed in the first 12 hours.^[11] If resolution of clinical signs of infection including normalization of white blood count and temperature does not occur after 24 hours postoperatively, antimicrobials can be continued for 4-7 days. Preferred agents include a beta-lactam/beta-lactamase inhibitor combination or a carbapenem. Some authors suggest that in patients with positive peritoneal fungal cultures or an elevated Mannheim Peritonitis Index score, antifungal therapy could also be of benefit,^[12] although this subject is controversial.

In cases in which evidence of persistent or recurrent infection after 4-7 days of therapy exists, the presence of abscesses or missed intraoperative injuries is certainly a possibility. At the same time, other sources of infection, like urinary or respiratory tract, catheters, and lines, should be investigated after intra-abdominal insults are ruled out.

H pylori eradication should also be considered. Some surgeons may opt for empiric postoperative eradication with anti-secretory medications and antibiotics once the patient is tolerating an oral diet, while others choose to test for H pylori and then treat only patients who test positive for H pylori. Eradication significantly decreases morbidity, mortality, and ulcer recurrence in patients with perforations associated with H pylori.^{[2, 3]}

Medication summary

• H pylori eradication: Amoxicillin, clarithromycin plus a proton pump inhibitor or metronidazole, clarithromycin plus a proton pump inhibitor for 10-14 days. For more information, please see the topic Helicobacter Pylori Infection.
• Antimicrobials for peritonitis: Beta-lactam/beta-lactamase inhibitor (eg, amoxicillin/clavulanic acid) or carbapenems (eg, ertapenem, imipenem). For more information, please see the topic Antibiotic Therapy for Peritonitis.

Preoperatively resuscitating patients with perforated ulcers is of the utmost importance

Improving outcome in high-risk surgical patients such as those with perforated viscus is a fundamental augmentation to the surgical treatment for source control. The importance of preoperative resuscitation has been underlined by Shoemaker in a study demonstrating improved mortality and morbidity in high-risk surgical patients with supranormal homodynamic and oxygen transport variables.^[13]

At the same time, the Surviving Sepsis Campaign and Guidelines has delineated key steps in the resuscitation of patients in sepsis or septic shock.^[14] The clinical improvement noticed with adequate preoperative resuscitation is derived from the concept of optimization of the circulation, augmentation of oxygen delivery to peripheral tissues by an adequate preload that would result in a high stroke volume.

Some of the physiologic parameters described in the original work in this area were derived using pulmonary artery catheters, which have more recently not been shown to yield superior results in terms of mortality compared with therapy directed by central venous pressure measurements. Therefore, commonly used parameters for goal-directed therapy in septic patients are the central venous pressure, lactic acid, or Scvo2. The urine output, blood pressure, and heart rate, while key indicators of hemodynamic instability, have been demonstrated to be less specific and reliable, and therefore are insufficient to drive goal-directed therapy in many septic patients.

Closed suction drainage is generally unnecessary in omental patching of perforated ulcers

The occlusive nature of the omental patch repair makes the addition of closed suction draining redundant. The patch is believed to adhere to the inflamed serosal layer of the bowel and thus seal the perforation. No difference exists in postoperative abscess rates without or with drains, and drains can themselves cause morbidity such as infection or erosion into visceral structures. Draining the free peritoneal cavity is generally believed to be impractical. However, if a walled-off abscess elsewhere in the abdomen accompanies the contamination derived from the perforated ulcer and this abscess cannot be broken up surgically, then a drain may be reasonably placed within the abscess cavity.

For perforated ulcer disease, an anti-acid surgical treatment by means of vagotomy is not always warranted

With introduction of proton pump inhibitors, chemical vagotomy replaced the need for surgical vagotomy with good success rates. In patients who are not compliant with medical treatment, surgical vagotomy at the initial time or repair for perforated ulcer should be considered. However, as discussed in the text, the hemodynamic status of the patient is a major determinant of the extent of surgical intervention.

Although omental patching is generally discussed in conjunction with the repair of duodenal ulcers, perforated gastric peptic ulcers can also be repaired using this technique

The option of omental patching of hollow viscus perforation is dependent on the location of the lesion and microbial flora of the respective portion of the bowel. Prepyloric or pyloric ulcers are in close proximity to the omentum and therefore can be patched with minimal tension, whereas ulcerations on the more proximal curvatures of the stomach are probably not easily accessible using this method. At the same time, the acidic environment in the stomach and proximal duodenum with minimal growth and proliferation of the normal flora of gram positive cocci makes the repair amenable to simple patching, assuring a tight closure upon inflammatory cell recruitment.

Conversely, more proximal gastric ulcers are more likely to be malignant. Malignant perforated ulcers should not be patched because they are unlikely to seal. Perforated malignant gastric ulcers should be at least wedge-resected if the patient is not sufficiently stable for a more classical cancer resection.