Omental (Graham) Patch

Omental patching began in 1937, when Roscoe Reid Graham of Toronto reported 51 cases of perforated peptic ulcer successfully treated with an omental patch. ^[1]  In Graham’s initial cases, he concluded that routine gastroenterostomy was unnecessary, the omental patch being more than sufficient for closure of the duodenal perforation. More than 80 years after its initial description, this technique is still extremely useful in selected patients with perforated duodenal ulcers.

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 by means of vagotomy and drainage or parietal cell vagotomy. However, since the introduction of proton pump inhibitors (PPIs), chemical vagotomy has decreased the rate of surgical vagotomy because of the high efficiency of PPIs 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 patching alone with postoperative use of PPIs and eradication of H pylori, as indicated, or it can include an omental patch with surgical control of gastric acid by means of vagotomy and drainage, parietal cell vagotomy, or antrectomy. ^[2] The choice of operation is dictated by the following:

• Pathology responsible for the perforation
• Patient’s premorbid health status
• Patient’s perioperative hemodynamic status
• Degree of contamination of the peritoneum that has been found

The omental patch alone is indicated in the following circumstances:

• Generalized peritonitis
• Hemodynamic instability with shock
• Perforation for more than 24 hours
• Perforation clearly associated with the use of nonsteroidal anti-inflammatory drugs (NSAIDs)
• Patient has not had significant symptoms for 3 months before the procedure

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 PPIs; mortality, morbidity, and ulcer recurrence with omental patch repair have all been shown to be extremely low. ^{[3, 4]}

It is possible that the balance will shift further away from definitive antiacid surgical intervention in the future; 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 the demonstration that long-term PPI use is associated with an increased incidence of hip fractures in the elderly will skew the balance in the opposite direction remains to be seen.

Omental patch repair has also been incorporated in the management of perforated gastric ulcers. ^[5] Perforated prepyloric or pyloric ulcers are amenable to closure with omental patch with minimal tension because of the close proximity of the injury. Gastric ulcers in atypical (more proximal) locations or with features suggestive of malignancy should not be patched but should be 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's hemodynamic status is poor, and rapid control of the septic source is required.

Gastric outlet obstruction is a recognized postoperative complication of patched pyloric or prepyloric ulcers, with a frequency of about 15%. ^[6]  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 Heineke-Mikulicz pyloroplasty. Another indication for this type of repair is in duodenal defects larger than 1 cm to allow 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

Omental patching with purse-string endosuture closure has been proposed as a potential means of closing large iatrogenic defects after endoscopic full-thickness resection (EFTR) of gastric gastrointestinal stromal tumors (GISTs). ^{[7, 8]}

Procedural planning

Preoperative resuscitation

Improving outcome in high-risk surgical patients such as those with a perforated viscus is a fundamental augmentation to surgical treatment for source control. The importance of preoperative resuscitation was underlined by Shoemaker in a study demonstrating improved mortality and morbidity in high-risk surgical patients with supranormal hemodynamic and oxygen transport variables. ^[9]

The Surviving Sepsis Campaign delineated key steps in the resuscitation of patients in sepsis or septic shock. ^[10]  The clinical improvement noticed with adequate preoperative resuscitation was derived from the concept of optimization of the circulation and 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 via pulmonary artery catheters, which have been shown not to yield superior results in terms of mortality as compared with therapy directed by central venous pressure (CVP) measurements. Therefore, commonly used parameters for goal-directed therapy in septic patients are CVP, lactic acid level, and central venous oxygen saturation. Urine output, blood pressure, and heart rate, though key indicators of hemodynamic instability, are less specific and reliable and therefore are insufficient to drive goal-directed therapy in many septic patients.

Closed suction drainage

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 thereby seal the perforation. Postoperative abscess rates are essentially the same with or without drains, and drains can themselves cause morbidity (eg, 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 reasonably be placed within the abscess cavity.

Surgical and chemical vagotomy in perforated ulcer disease

With the introduction of PPIs, chemical vagotomy largely supplanted 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.

Omental patch for perforated gastric peptic ulcer

The option of omental patching of hollow viscus perforation is dependent on the location of the lesion and the microbial flora of the respective portion of the gastrointestinal (GI) tract. 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 probably are not easily accessible with 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 stable enough to undergo a more classical cancer resection.

Omental patch repair does not correct the underlying process that causes perforation, and ulcers may recur. In a study of 94 patients with perforated foregut ulcers (53 gastric and 41 duodenal), of whom 77 (82%) were treated by omental patching alone, Smith et al documented a 12% rate of ulcer recurrence after omental patching and a 23% incidence of recurrent symptoms within 44 months. ^[11]