Transgastric biologic mesh delivery and abdominal wall hernia repair in a porcine model.

BACKGROUND AND STUDY AIMS: Incisional abdominal wall hernias currently require repair with open or laparoscopic surgery, which is associated with wound complications and recurrent hernia formation. Natural orifice transluminal endoscopic surgery (NOTES) techniques may have the potential to decrease the morbidity associated with hernia repair. The aim of this study was to repair a chronic ventral hernia with a biologic mesh placed transgastrically in a porcine model. MATERIALS AND METHODS: Six pigs underwent creation of an incisional abdominal wall hernia. At least 4 weeks later, transgastric repair was done using an underlay biologic mesh with at least 5 cm of overlap from the hernia fascial edge. The mesh was secured with transfascial sutures and the stomach was closed with a sutured gastropexy. Pigs were evaluated 2 weeks later by laparoscopy. Pigs were sacrificed and necropsy wa s performed 4 weeks after the repair. RESULTS: Six pigs underwent hernia repair lasting a mean (+/- SD) of 204 +/- 123 minutes, with one perioperative death. At 2 weeks after hernia repair, laparoscopy showed significant adhesions in all pigs; one pig had extensive mesh infection and was sacrificed. Necropsy on one pig at 2 weeks and four pigs at 4 weeks showed complete coverage of the hernia defect in all pigs. All pigs had mesh abscesses or a positive mesh culture. CONCLUSION: Transgastric repair of a chronic ventral hernia is technically feasible. Difficulties with mesh delivery and infection need to be overcome before this approach can be used in humans.

Endoscopic colotomy closure after full thickness excision: comparison of T fastener with multiclip applier.

BACKGROUND AND STUDY AIMS: Safe, reliable, and efficient endoscopic closure of a colotomy is paramount for endoscopic full thickness excision of the colon. Two newly developed devices, the Tissue Apposition System (TAS) and the InScope Multi-Clip Applier (IMCA), may help to achieve this. The aim of this study was to determine the feasibility of using each device to close colotomies after full thickness wall excisions. MATERIAL AND METHODS: 12 pigs were used in the study. After laparoscopic full thickness excision of the colonic wall, the defect was closed using either the TAS or the IMCA. Closure was performed under laparoscopic vision. Success of colotomy closure, time taken for colotomy closure, postoperative infections, and complication rates were recorded. RESULTS: Complete closure was achieved in 6/6 pigs in the TAS group. In 5/6 pigs in the IMCA group closure was successful; in one pig laparoscopic assistance was used. Median closure time (range) was significantly lower in the TAS group at 48 minutes (15 - 51) vs. 76 minutes (43 - 145) in the IMCA group. There were no postoperative infections or complications. CONCLUSIONS: Endoscopic closure after full thickness colonic wall excision is feasible with both the TAS and the IMCA. Closure times are significantly shorter and handling is easier with the TAS. Combined use of both systems might be beneficial.

Evaluation of a novel endoluminal stapling procedure to restrict the lower esophageal sphincter and reduce reflux.

BACKGROUND AND STUDY AIMS: An effective, safe, and long-lasting endoluminal treatment for gastroesophageal reflux disease (GERD) would be an attractive prospect. We developed an endoluminal technique to restrict and tighten the lower esophageal sphincter (LES), by using a transoral endoscopic stapling device in a porcine model. PATIENTS AND METHODS: Pre-interventional evaluation comprised endoscopy, manometry, and 48-hour pH measurement of the distal esophagus using the catheterless BRAVO pH capsule. By placing the endoluminal stapling device at the LES and firing a 2.5-cm staple line, a vertical plication was created. In five pilot pigs (phase 1), plications were placed in various locations at the LES. In another five pigs (phase 2), plications were placed uniformly at the mid level of the LES on the lesser curvature side. Measurements were repeated 2 weeks after the procedure. Necropsy and histological analysis were performed. RESULTS: Endoluminal stapling was successfully completed in all animals. In phase 2, the median procedure time was 15 minutes (range 10-55 minutes). LES pressure increased from 10.5 mmHg (+/- 2.5 mmHg) to 14.3 mmHg (+/- 3.8 mmHg) (P = 0.038). Median percentage of time with pH below 4 decreased from 6.6% (range 2.9%-48.8%) to 2.2% (range 0%-10.4%) (P = 0.043). Histology showed the staple line involving the muscular layer in all pigs. A gap was present in the central part of the staple line in three pigs resulting in a mucosa-muscular bridge of tissue. This bridge did not influence the results. CONCLUSION: This novel endoluminal technique is feasible and safe in a porcine model over 2 weeks. It is appealing due to its simplicity and ease of application. Further studies aimed at eliminating the gap in the staple line and investigating more animals over longer survival periods are needed.

Uroguanylin treatment suppresses polyp formation in the Apc(Min/+) mouse and induces apoptosis in human colon adenocarcinoma cells via cyclic GMP.

The enteric peptides, guanylin and uroguanylin, are local regulators of intestinal secretion by activation of receptor-guanylate cyclase (R-GC) signaling molecules that produce cyclic GMP (cGMP) and stimulate the cystic fibrosis transmembrane conductance regulator-dependent secretion of Cl- and HCO3-. Our experiments demonstrate that mRNA transcripts for guanylin and uroguanylin are markedly reduced in colon polyps and adenocarcinomas. In contrast, a specific uroguanylin-R-GC, R-GCC, is expressed in polyps and adenocarcinomas at levels comparable with normal colon mucosa. Activation of R-GCC by uroguanylin in vitro inhibits the proliferation of T84 colon cells and elicits profound apoptosis in human colon cancer cells, T84. Therefore, down-regulation of gene expression and loss of the peptides may interfere with renewal and/or removal of the epithelial cells resulting in the formation of polyps, which can progress to malignant cancers of the colon and rectum. Oral replacement therapy with human uroguanylin was used to evaluate its effects on the formation of intestinal polyps in the Min/+ mouse model for colorectal cancer. Uroguanylin significantly reduces the number of polyps found in the intestine of Min/+ mice by approximately 50% of control. Our findings suggest that uroguanylin and guanylin regulate the turnover of epithelial cells within the intestinal mucosa via activation of a cGMP signaling mechanism that elicits apoptosis of target enterocytes. The intestinal R-GC signaling molecules for guanylin regulatory peptides are promising targets for prevention and/or therapeutic treatment of intestinal polyps and cancers by oral administration of human uroguanylin.

Pacing the human stomach.

The aim of this study was to document the pattern of human gastric pacesetter potentials after abdominal operation and to determine whether the potentials could be paced by electrical stimuli. Ten patients undergoing cholecystectomy had temporary serosal electrodes positioned along the greater curvature of the stomach. Bipolar myoelectric recordings and attempts at electrical pacing were made after operation. On postoperative day 1, the pacesetter potentials had a regular frequency (3.2 +/- 0.1 cycles/min), and no gastric dysrhythmias were evident. The distal stomach of nine of ten patients could be entrained by pacing the proximal electrodes (forward pacing) to a maximal rate of 4.3 +/- 0.3 cycles/min (p less than 0.05 versus nonpacing) without a change in propagation velocity or direction. Backward pacing (maximum rate, 3.9 +/- 0.2 cycles/min) was possible in six patients. Forward pacing was successful by day 3 in only four of ten patients, and backward pacing was successful in none of ten patients. A meal given a median of 3.5 days after operation did not change the pacesetter potential frequency, rhythm, or direction of propagation, and three of ten patients had successful forward pacing after a meal. In conclusion, a regular pattern of gastric pacesetter potentials is present after cholecystectomy. The gastric pacesetter potentials can be paced with electrical stimuli, although refinements of the pacing electrodes or stimuli will be needed to achieve long-term pacing. Pacing holds promise as a potential treatment for gastric myoelectrical disorders.

The Roux stasis syndrome. Treatment by pacing and prevention by use of an 'uncut' Roux limb.

Ectopic pacemakers in the Roux limb are associated with delayed gastric emptying after Roux gastrectomy. The aim herein was to suppress the ectopic pacemakers by electrical pacing or to prevent them by maintaining enteric myoneural continuity with an "uncut" Roux limb, and so improve the delayed emptying. Among eight dogs with truncal vagotomy and Roux hemigastrectomy, four dogs had a pacing electrode applied to the proximal end of the Roux limb. The other four dogs had a gastrojejunostomy to an uncut Roux limb. In them, the afferent jejunal limb was occluded by staples but not divided, and a diverting jejuno-jejunostomy was performed. Roux pacing and the uncut Roux operation abolished ectopic pacemakers in the Roux limb and speeded the slow gastric emptying present in unpaced control tests. At autopsy, however, dehiscences were found in the staple line in the dogs with the uncut Roux procedures. In conclusion, electrical pacing and the uncut Roux limb show promise as techniques to prevent ectopic jejunal pacemakers and gastric stasis after Roux gastrectomy. Both must be improved before they can be used in patients.

Complications following pancreaticoduodenectomy. Current management.

From 1980 to 1989, 279 patients underwent pancreaticoduodenectomy at a single institution with a postoperative mortality of 4%. The aim of this study was to determine incidence, origin, and present management strategy of early complications following this operation. Significant morbidity occurred in 46% of the patients, including delayed gastric emptying (23%), pancreaticojejunal anastomotic leak (17%), intra-abdominal sepsis (10%), biliary-enteric anastomotic leak (9%), gastrointestinal tract bleeding (5%), and intra-abdominal hemorrhage (3%). Complications were associated with advanced age, prolonged operations, and increased operative blood loss. Most complications were managed nonoperatively. Mortality was increased when a reoperation was required, a biliary-enteric leak occurred, or an intra-abdominal abscess developed. Pancreaticoduodenectomy continues to carry a high postoperative morbidity; however, operative mortality is low, and management of complications has been made simpler with more sophisticated, nonoperative therapeutic options.

The Roux operation for postgastrectomy syndromes.

The aim of this paper is to describe the technique, indications, and results of the Roux operation as used in the treatment of postgastrectomy syndromes. A Roux gastrojejunostomy with a 40-cm Roux limb is the procedure of choice for alkaline reflux gastritis, because it virtually eliminates reflux of bile and pancreatic juice into the stomach. The slow transit through a Roux limb can also be used to good advantage to slow gastric emptying in patients with dumping. Patients with delayed gastric emptying respond to the combination of near-total gastric resection, which removes the atonic gastric remnant and speeds emptying, and Roux-Y gastrojejunostomy, which prevents reflux esophagitis and provides a reservoir for ingesta in the upper gut. After all Roux operations, however, the Roux limb may slow emptying so much that pain, fullness, nausea, and food vomiting result, the so-called Roux stasis syndrome. Prevention of the Roux stasis syndrome with an "uncut" Roux limb and the treatment of the syndrome by using electrical pacing to suppress the ectopic pacemakers that emerge in the limb offer possible new solutions to this vexing problem.

Electrical dysrhythmias in the Roux jejunal limb: cause and treatment.

Electrical dysrhythmias in the Roux limb after Roux gastrojejunostomy are associated with upper gut stasis of food. The aim of this study was to determine the cause of the dysrhythmias and whether they could be eliminated with pacing. A set of four dogs (Group A) underwent three sequential operations: placement of jejunal electrodes at sites corresponding to the Roux limb; construction of a Roux limb without vagotomy, gastrectomy, or gastrojejunostomy; and transthoracic truncal vagotomy. A second set of five dogs (Group B) underwent truncal vagotomy, distal gastrectomy, and Roux gastrojejunostomy with recording electrodes placed on the Roux limb and a pacing electrode situated at the proximal end of the limb. Electrical recordings were obtained on four separate occasions after each operation. In Group A dogs, orad and disordered propagation of jejunal pacesetter potentials occurred in the Roux limb 56 +/- 5% of the time after limb construction but never before construction. The pattern was not changed with vagotomy. In Group B dogs, electrical dysrhythmias in the Roux limb also occurred and were corrected with electrical pacing. We concluded that electrical dysrhythmias in the canine Roux limb are secondary to the jejunal transection done during Roux limb construction, and are not due to gastrectomy, gastroenterostomy, or vagotomy. The dysrhythmias can be corrected with pacing.

Proximal gastric vagotomy in the emergency treatment of bleeding duodenal ulcer.

Proximal gastric vagotomy for bleeding duodenal ulcer was performed in 52 low-risk patients between 1973 and 1986. Duodenotomy without violation of the pylorus was done in all patients to allow inspection and control of the bleeding site. The median duration of operation was 3 hours and 20 minutes, although 25% of the procedures required 4 or more hours. There was no postoperative mortality and no early reoperations. Among the six patients with postoperative complications, one rebled from the ulcer and two developed prolonged gastric atony. At the time of follow-up (median, 2.9 years), 48 of the patients were alive and 4 had died of non-ulcer causes. No patient had significant postvagotomy sequelae. Ulcer recurrence was documented in six patients, and three required reoperation. Proximal gastric vagotomy is a safe, effective therapy for bleeding duodenal ulcer. Because of the length of the operation, it should be restricted to low-risk patients who are hemodynamically stable at the time of operation.

Postgastrectomy syndromes.

Anatomic and physiological changes introduced by gastric surgery result in postgastrectomy syndromes in approximately 20% of patients. Most of these disorders are caused by operation-induced abnormalities in the motor functions of the stomach, including disturbances in the gastric reservoir function, the mechanical-digestive function, and the transporting function. Division of the vagal innervation to the stomach and ablation or bypass of the pylorus are the most significant factors contributing to postgastrectomy syndromes. Either rapid or slow emptying may result, depending on the relative importance of lack of a compliant gastric reservoir, loss of an effective contractile force, and loss of controlling factors that slow or speed gastric emptying and result in duodenal-gastric reflux. Clearly defining which syndrome is present in a given patient is critical to developing a rational treatment plan. In syndromes with slow gastric emptying, bilious vomiting, or alkaline reflux gastritis, the use of endoscopy is essential to rule out mechanical causes of the syndrome. Contrast radiography and scintigraphic gastric emptying studies are useful to document rapid or delayed gastric emptying. Postgastrectomy syndromes often abate with time. Conservative measures, including medical, dietary, and behavioral therapy, should be given at least a 1-year trial. If these nonoperative measures fail, surgical therapy is recommended. The Roux-en-Y gastrojejunostomy is useful for patients with dumping, because it slows gastric emptying and the transit of chyme through the Roux limb. The same operation helps patients with alkaline reflux gastritis, because it diverts pancreaticobiliary secretions away from the gastric remnant. Near-total gastrectomy, which reduces the size of a flaccid gastric reservoir, can be used to treat delayed gastric emptying. This operation should be combined with the Roux procedure to prevent postoperative reflux gastritis and esophagitis. Newer techniques, such as gastrointestinal pacing and the uncut Roux operation, may improve the treatment of the postgastrectomy syndromes in the future.

Percutaneous cholecystostomy is an effective treatment for high-risk patients with acute cholecystitis.

We sought to determine the safety, efficacy, and outcome of percutaneous cholecystostomy (PC) in all patients undergoing the procedure at our institutions. We reviewed 53 consecutive cases of acute cholecystitis seen at our hospitals over 5.5 years in which PC was performed at the initial treatment. Follow-up was obtained by chart review and telephone questionnaire. Acute cholecystitis was the primary admitting diagnosis in 18 cases. In the remaining 35, cholecystitis developed during hospitalization. All patients were considered high surgical risks on the basis of the presence of comorbid conditions. The gallbladder was successfully catheterized under radiologic guidance in all patients and with no immediate procedure-related morbidity. Acute cholecystitis resolved in 44 of 53 patients (83%), whereas nine patients (17%) did not improve clinically after PC and died during the same hospitalization. A total of 33 (62%) eventually survived hospitalization. Elective cholecystectomy was done in 25 patients with no mortality. After cholecystectomy, three of these patients subsequently died of other causes, whereas 22 are alive. Eight patients did not undergo cholecystectomy because of underlying medical conditions or because they had acalculous cholecystitis. These patients remained free of biliary problems after removal of their cholecystostomy tube, but two have subsequently died of nonbiliary conditions. Percutaneous cholecystostomy is a safe, effective treatment for high-risk patients with acute cholecystitis. Cholecystostomy can be followed by elective cholecystectomy at a later time if the patient's condition permits or by expectant conservative management in patients who have had acalculous cholecystitis or have a very high mortality risk with surgery.

A prospective trial of primary inguinal hernia repair by surgical trainees.

The main hypotheses were that the Lichtenstein inguinal hernia repair has a lower recurrence rate and similar incidence of chronic groin pain compared to sutured repairs when performed by surgical trainees. In a U.S. Veterans Administration Hospital, 150 primary hernia repairs were randomized to a Lichtenstein, McVay, or Shouldice repair. The Shouldice repair included a routine relaxing incision. First- and second-year residents, under the supervision of an experienced general surgeon, performed the procedure. Long-term follow-up was obtained in 81% of patients. Hernia recurrence rate was Lichtenstein 8%, McVay 10%, Shouldice 5% ( P>0.1) at 6-9 years follow-up. More patients had chronic groin pain following Lichtenstein repair (38%) than after Shouldice repair (7%) ( P<0.05). More information is needed on long-term groin pain following anterior mesh repair. The Shouldice inguinal hernia repair may have a role in open primary herniorrhaphy to decrease the risk of chronic groin pain.

Rectal cancer. Treatment advances that reduce recurrence rates and lengthen survival.

The risk of malignant disease arising in rectal mucosa is high. Surgery is the most effective form of treatment but results in cure in only 50% of patients. Adjuvant preoperative radiation therapy reduces the likelihood of local recurrence but does not improve survival rates. Fluorouracil is the most effective agent for adjuvant chemotherapy and slightly improves survival when given after surgery. Combining radiation therapy with chemotherapy appears to have a synergistic effect, and recent studies show that providing this combination after surgery improves survival. Future trends in the treatment of rectal cancer are expected to include expanded use of local excision to preserve anal sphincter function, preoperative use of a combination of radiation therapy and chemotherapy, perioperative use of chemotherapy combined with immunostimulating therapy, and use of tumor antibodies for diagnostic and therapeutic purposes.

Colonic diverticula. When complications require surgery and when they don't.

The value of a high-fiber diet in preventing and treating colonic diverticula is firmly established. Although the diagnosis of diverticulosis is usually made with colonoscopy or barium enema examination, computed tomography has become the test of choice during acute diverticulitis, when the diagnosis cannot be confidently made clinically. Recently developed surgical principles for diverticulitis include radiographically directed drainage with delayed operation for peridiverticular abscess, resection of the site of disease in patients with general peritonitis, and primary anastomosis in most cases requiring urgent intervention. Diverticulosis accompanied by abdominal pain or irregular bowel habits is by itself rarely an indication for surgery. Diverticular bleeding usually resolves spontaneously, but persistent bleeding can usually be successfully treated with segmental colectomy after localization of the bleeding site with colonoscopy or arteriography.

Retrorectus polyester mesh repair for midline ventral hernias.

PURPOSE: To evaluate the effectiveness of the retrorectus mesh repair for midline ventral hernias. METHODS: A retrospective review of all consecutive patients having a retrorectus mesh repair by a single surgeon in a standardized fashion from 1991 to 2005. All procedures used polyester (Mersilene) mesh with at least 5-cm overlap beyond the repair in all directions. RESULTS: Ninety patients were identified, 56% of which were female. Major postoperative complications occurred in 23 (26%) patients, including nine (10%) patients requiring reoperative treatment due to skin flap necrosis, wound infection, hematoma, or fascial dehiscence. Partial mesh excision was required in four patients. The hernia recurrence rate was 7% at a mean of 53 months. CONCLUSION: The retrorectus repair with polyester mesh is an effective and durable repair for midline ventral hernias. The disadvantage of this repair is the large number of wound complications.

Laparoscopic assisted percutaneous endoscopic gastrostomy.

Percutaneous endoscopic gastrostomy (PEG) cannot be accomplished in some patients and should not be performed if a distinct indentation in the stomach is not seen with finger pressure on the abdominal wall. We describe a technique of laparoscopic assisted PEG as an alternative to evaluate the intraabdominal organs after failed PEG placement. A needle is placed percutaneously into the stomach under laparoscopic and gastroscopic control. A wire is placed through the needle, encircled with a snare, and the PEG completed. We have performed this technique in three patients without complication. This simple and safe procedure has become our technique of choice for gastrostomy tube placement in those patients where upper endoscopy is possible but a PEG alone cannot be performed safely.

Irreversible renal failure following right nephrectomy and left renal vein ligation.

Ligation of the left renal vein has been advocated in certain clinical situations and venous outflow then is dependent on an adequate collateral venous system. We report on a child who suffered complete renal failure after ligation of the left renal vein in association with right nephrectomy and, subsequently, died. The left renal vein should be repaired in the presence of a solitary left kidney to prevent renal vein thrombosis and subsequent renal failure. This is particularly true in children in whom venous collateral circulation of the left kidney may not be well developed.

The diagnosis and treatment of pyogenic liver abscesses.

Pyogenic liver abscesses in 106 adult patients at The New York Hospital were reviewed to define optimum treatment. Mortality in the surgically treated patients was 26% (17/65), while those treated nonsurgically had a fatality rate of 95% (39/41). Multiple abscesses treated surgically had a surprisingly low mortality of 29% (5/17). Modern noninvasive tests are highly sensitive in diagnosing liver lesions greater than 2 cm. Difficulty remains in identifying small hepatic abscesses and differentiating large abscesses from tumor. Most liver abscesses have an identifiable source outside the liver. The most common source (31%) was cholangitis secondary to extrahepatic biliary obstruction. Multiple abscesses, mixed organisms, hyperbilirubinemia, and abscess complications are all associated with a significantly increased mortality. However, the lethality of the primary disease process was the most important factor determining survival. Most patients who have the underlying pathogenesis of the abscess controlled will survive surgical treatment. Transperitoneal surgical drainage and antibiotics remain the mainstay of treatment. Percutaneous drainage is recommended for high risk patients only.