Complications Arising from Staple Lines and Anastomotes in Bariatric Surgery: Why They Happen and How to Avoid Them

| November 17, 2009

by Dugal Heath, MD, FRCS, FRACS

Bariatric Times. 2009;6(11):8–12.

INTRODUCTION

The invention of stapling devices, which can be used in laparoscopic surgical procedures, provides a number of benefits to surgeons. They are simple to use, provide a rapid means of dividing and joining bowel, and require less skill and experience on the part of the operator than that required for laparoscopic hand suturing. In spite of these benefits, their use is associated with a variety of problems, including leakage from staple lines or anastomoses, bleeding, and fistula formation,[1] which can, on occasion, prove fatal. This paper examines factors that are important in leading to these complications and suggests ways to avoid them.

ABSTRACT
Leaks from staple lines or anastomoses represent a significant cause of morbidity and mortality in patients undergoing bariatric procedures. Stapling devices are used for dividing and joining bowel and it is now possible to complete a bariatric procedure, such as Roux-en-Y gastric bypass, without sutures, although many surgeons continue to use sutures for at least part of this procedure. Leaks may occur as a result of failure of the stapling device to work correctly, because they are employed under circumstances or in tissues for which they were not designed or because of “surgeon factors.” This paper examines the available evidence surrounding staple line and anastomotic leaks from laboratory-based and clinical studies and suggests strategies for minimizing leaks.

THE STAPLING DEVICE
Laparoscopic stapling devices are designed to facilitate the division of a piece of tissue or tissues, while at the same time ensuring that the divided ends are sealed. In bariatric surgery, the tissues most commonly divided are stomach and small bowel, although stapling devices can also be applied across mesentery, lung, heart, and blood vessels. In the linear cutting staplers, two or more rows of staples (most commonly three) are laid down either side of a central channel, through which a blade passes. When the device is fired, the action leads to the sealing and division of the tissue. The gastric pouch in laparoscopic Roux-en-Y gastric bypass (RYGB) is formed using such a device. Linear cutting staplers can also be used to join pieces of bowel, such as in the formation of the gastrojejunal anastomosis in RYGB. The stapling device is inserted into small holes made in the small bowel and gastric pouch (enterotomies and gastrotomies, respectively). When fired, the device joins the stomach to the small bowel and divides the tissue between them making an anastomosis. The size of the anastomosis depends upon the length of the cartridge and the degree to which it is inserted, the longer the cartridge and/or the more that is inserted, the larger the lumen. Once the stapling device is withdrawn, the remaining hole in the anterior wall of the anastomosis can be closed with a further firing of the device or a suture. Circular devices may also be used to join bowel and have the advantage of no enterotomy to be closed at the site of the anastomosis, making this method quicker than side-to-side stapled anastomoses. Side-to-side joining of the jejuno-jejunostomy is almost universally achieved with a linear cutting stapling device.

STAPLING DEVICE CARTRIDGES
Manufacturers provide a combination of different cartridge lengths, each with staples that close to a different height. These differing staple heights are designed to ensure that, when closed, the staples provide secure apposition of the edges of the bowel.[2] If the staple height is too low, the staples can cut through the tissue or lead to tissue ischemia, resulting in leakage. If the staple height is too high, the staples fail to ensure adequate apposition, leading to bleeding from the staple line or leakage.[2] Reported leakage and hemorrhage rates following bariatric procedures employing stapling devices vary between 0 and 20 percent and 0.6 to 4.4 percent,[1,3–5] respectively. Most surgeons aim to achieve an anastomotic or staple line leak rate under four percent for primary procedures.

SELECTING THE CORRECT STAPLE HEIGHT
The difficulty for the surgeon lies in selecting the correct staple height for each tissue in each patient. While the stomach is generally thicker than the small bowel and therefore requires a greater staple height, not all parts of a hollow viscus are the same thickness. Measurements of human cadaveric stomach has shown that gastric wall thickness can vary between 0.3 and 3.73mm, even within the same individual.[2] Furthermore, difficulties arise in selecting which staple height should be employed when joining tissues with different thicknesses, such as small bowel and stomach or in patients undergoing revisional surgery.

Experimental studies[2] undertaken at the Scientific Institute for Surgical Devices and Instruments in Russia revealed that the optimal tissue compression required for stomach is 8g/mm2 and for small bowel and esophagus 6g/mm2. This information has been applied in the development and design of stapling devices with the aim of producing the optimal application of pressure and staple height for each firing.

For one manufacturer of stapling devices (Ethicon EndoSurgery, Cincinnati, Ohio), these figures translate into using green (closed staple height 2mm) cartridges on the stomach and blue (closed staple height 1.5mm) on the small bowel. The manufacturer states that blue cartridges should not be used on any tissue that requires excessive pressure to compress it to 1.5mm or on any tissue that easily compresses to less than 1.5mm. While it might be possible for a surgeon to detect that a stapling gun requires excessive force to close, it is difficult to envisage how a surgeon might be able to conform to these criteria other than by opening the stapling device before firing and measuring the thickness of the tissue. When performing laparoscopic RYGB, it is common for surgeons to select blue cartridges for the stomach and white for the small bowel (closed staple height 1mm), because bleeding was observed from the staple line when greater staple heights were employed. To add to the confusion, gold cartridges are now available with a closed staple height of 1.8mm, and different manufacturers’ staples close to different heights. Some surgeons employ blue cartridges in female patients and green cartridges in male patients undergoing primary procedures, either with or without staple-line reinforcement agents. Some surgeons employ a blue cartridge for the first transverse firing and then green cartridges thereafter.

Revisional bariatric procedures are associated with an anastomotic leak rate of 10 percent as opposed to the more usually quoted rate of four percent after primary procedures with an increased rate of reoperation (13%).[5] The increased number of leaks in revision bariatric procedures may be associated with increased tissue thickness or reduced blood supply, although there are no hard data to support these theories. Even so, it is not unreasonable to assume that adhesions and adherent tissues, such as omentum, as well as the possibility of the development of tissue edema consequent upon the dissection required to gain access, increases tissue thickness. Increased tissue thickness may also occur as the result of folding of the stomach. This occurs in patients who have had a gastric band inserted, where a gastrogastric tunnel has been formed, and who are undergoing revision to a RYGB. If this gastrogastric tunnel is not taken down prior to pouch formation, then the stapling gun will be firing through four rather than two layers of the stomach with an associated risk of incomplete staple formation, leakage, and hemorrhage. Identification of the gastrogastric tunnel is straightforward where the band is still in situ at the time the RYGB is undertaken. However, if the band was removed at a prior operation and the tunnel not taken down at this time, then the difficulty of ensuring the stomach is completely flat prior to the formation of the pouch is greatly increased. There are no data to guide the surgeon in deciding which staple height to select in revision procedures. In view of the difficulties in demonstrating significant differences in staple line and anastomotic security in primary procedures, it is likely that any study examining the less frequently occurring revision procedures will take a long time to recruit sufficient numbers, even when the increased staple line/anastomotic leak rate is taken into account. The British Obesity and Metabolic Surgery Society (BOMSS) recently instigated a National Bariatric Surgery Registry, which has collected data on 2,000 procedures in its first six months and may provide data to help answer the question of which staple height to select in revision procedures. Discussion with colleagues undertaking revision procedures revealed a tendency to use a greater staple height, employing green rather than blue cartridges with or without some form of staple-line reinforcement in dividing the stomach. However, one surgeon I spoke with employs green cartridges with a staple-line reinforcement agent in both primary and revision procedures.

While it is conceivable that a time will come when stapling devices will be able to measure the tissue thickness and close staples to the optimal height, for the time being we have to rely on the manufacturers’ recomendations. Of course, the real test is whether the guns, regardless of theoretical considerations, provide a secure and hemostatic closure. For an answer to these questions, we turn to laboratory and clinical studies.

EXPERIMENTAL STUDIES ON STAPLE HEIGHT AND LEAK RATES
In a cadaveric model employing stapling devices with staples of differing heights, it was noted that the strength of the staple line was significantly greater where the stomach was closed with green rather that blue cartridges.[2] It was also noted that where too low a staple height was selected (in this case employing a blue cartridge on stomach) there was a risk of the staples not forming properly or the stomach tearing. The latter was probably a result of the tissue being unable to deform sufficiently or quickly enough under the compressive force applied when the stapling device was closed prior to firing.[2] Both events have the potential to lead to leaks.

SURGEON FACTORS THAT AFFECT THE SUCCESS OF STAPLING DEVICE USES
While the surgeon’s choice of stapling device and, more particularly, the height of staples may be important in influencing staple-line-related complications, it has been difficult to demonstrate significant difference in the incidence of bleeding or leakage in clinical studies. This is in spite of the knowledge acquired from experimental studies that clearly demonstrates differences in burst pressure with differing staple heights.[2] Reasons for this include the fact that there may be a minimum security required, which is exceeded by even the “least appropriate” selection of staple height. Support for this idea comes from two studies.[6,7] The first examined the use of two different stapling devices (Ethicon Endo Surgery and United States Surgical Corporation [USSC]) and employed 3.5mm height on the stomach, 2.5mm on the small bowel, and 2.0mm (USSC) and 2.5mm (Ethicon) on the mesentery.[6] There were more misfires, more Hemoclips applied to control bleeding, a greater estimated blood loss, and longer procedure time with the Ethicon product. There was one anastomotic leak with the Ethicon product, and two patients were returned to the operating room because of postoperative bleeding with the USSC product. Therefore, it appears that in regard to significant complications, there is no significant difference between the two products or the differing staple heights. A study employing vascular staplers has demonstrated that the sealing of arteries up to 17mm and veins up to 22mm was achieved to supraphysiological pressure with both 2.0 and 2.5mm staple heights.[7]

Employing the knowledge gained from their studies, Baker et al[2] modified their surgical technique and reduced leak rate from one percent to less than 0.3 percent. They did not describe exactly what was done; however, it would be reasonable to assume that these changes incorporated changes to the surgeon’s choice of staple height, the way in which the surgeon employed these devices, and awareness of the pitfall of using these devices and techniques. Baker et al[2] may have also employed staple-line reinforcement, which we will discuss shortly.

Surgeon-dependent failures include the incorporation of too much tissue in the stapling device, which will result in the tissue being “bunched up” and lead to the staple being improperly formed or tearing through. Failures of staple-line formation can also occur where an incompletely formed staple becomes caught in the next firing of the staple gun, leading to a misfire. This can be guarded against by examining the staple line at the end of each firing and removing malformed staples. Clips used to secure hemostasis are relativly thick and will stop the proper functioning of the stapling device if caught in the jaws. Inaccurately aligned consecutive firings of the gun can produce an area of devitalized tissue between the staple lines and inadvertent inclusion of the esophagus in the last firing of the device at the angle of His may also produce leakage because the esophagus is less able to hold staples securely. There are also a number of other technical failures that can occur, including, for example, failures to form the enteroenterostomy correctly when a double-stapling technique is employed. In this technique, the stapling device is inserted into a centrally placed enterotomy and fired both up and down from this point. It is possible to exclude a central portion of the back wall, leading to a leak. This can be difficult to identify unless the inside of the bowel is examined.

The crossing of one staple line with another staple line at right angles is a potential area of weakness and has been examined in relation to esophageal and colorectal surgery in an animal model.[8,9] This can occur in side-to-side anastomoses as well as those in which a circular stapler is used. Possible causes of a weakness at intersecting staple lines would include the malformation of the staples from striking other staples or ischemia. Zilling and Walther[8] performed functional end-to-end anastomosis on segments of small and large bowel in 22 pigs. The animals were sacrificed at 24 hours and the anastomoses were examined to see whether there was reduced blood flow at the site of intersecting staple lines. The reduction in blood flow at crossed as opposed to noncrossed staple lines was six percent (-5 to -17 percent) for small bowel anastomoses and seven percent (-6 to -19 percent) for colonic anastomoses. Zilling and Walther suggested that these differences were not significant.[8] Zilling et al[9] also examined the blood flow at crossed and noncrossed staple lines of a gastrojejunostomy in 22 pigs who underwent total gastrectomy and oesophagojejunostomy. In all but one animal, the reduction in blood flow at crossed staple lines was  less than 25 percent and led the authors to conclude that intersecting staple lines in esophagojejunal anastomoses did not reduce mean anastomotic blood flow to a dangerous level.

In forming a gastroenteric anastomosis in RYGB, it is necessary to open the lower end of the gastric pouch. This may be done through the staple line of the gastric pouch (this method is my preferred method because when the stapling device is fired, it produces a side-to-side anastomosis, which does not include any prior staple line). Some surgeons open the pouch above the transverse staple line such that this is then crossed by the firing, which creates the anastomosis. Similarly, inclusion of part of the transverse staple line at the lower end of the pouch will occur if a circular stapler is employed. In spite of the theoretical risks of crossing the staple line, there is no evidence that this is associated with an increased leak rate. In a hand-sewn or side-to-side stapled anastomosis where the gastrotomy is made close to but just above the staple line, there is a theoretical risk that the thin strip of tissue between the transverse staple line of the pouch and the anastomosis may become ischemic. This does not appear to be the case in clinical practice.
Gonzalez et al[10] noted that while the time taken to operate reduced with surgeon experience and the size of patients increased, there was no reduction in anastomotic leak rate below that achieved after the learning curve was overcome. This suggests that anastomotic leaks, at least in part, are dependent on factors other than technical skill and experience.

STAPLE LINE REINFORCEMENT AGENTS
Attempts to improve staple line security and reduce bleeding have resulted in the introduction of staple-line reinforcement agents. Seamguard® (SG) (W.L. Gore & Associates, Inc., Flagstaff, Arizona) is one of these agents. The original product was made from expanded polytetrafluroethylene (ePTFE), which was nonabsorbable but has been replaced with an absorbable product (Seamguard Bioabsorbable) (SGB) (W.L. Gore & Associates, Inc.) made from a combination of polyglycolic acid and trimethylene carbonate. Another agent made by Synovis Surgical Innovations (St. Paul, Minnesota) is composed of bovine pericardium and comes in two forms. The original Peri-Strips® (PS) are nonabsorbable and Peri-Strips Dry® with Veritas® Collagen Matrix (PSDVCM) is partially absorbable. The potential disadvantage of nonabsorbable materials is that they can calcify, erode, and lead to the development of adhesions or be coughed up or regurgitated.[11]

ANIMAL STUDIES STAPLE LINE REINFORCEMENT AGENTS
Baker et al[2] conducted studies involving small bowels of pigs and cadaveric human stomach. In the former study, the inclusion of SG significantly increased the burst pressure of the staple line. When applied in an experimental model involving cadaveric human stomach, SGB significantly increased the strength of the staple line when employed with either blue or green cartridges. However, staple line failure was less common with green than blue cartridges. While the reason for this was not identified, it may be related to the fact that the inclusion of the extra thickness of the SG with the blue gun led to tearing of the stomach or failure of the staples to form properly.

Arnold and Shikora[12] examined the burst pressure of staple lines in the small bowel of pigs and in rabbit stomachs. Burst pressures of staple lines were significantly higher where PSDVCM were used. Most buttressed staple-line failures occurred away from the staple line (consistent with tearing of the tissue); whereas, the nonbuttressed segments failed at the staple line.

Mery et al[13] also tested staple-line burst pressures in an ex-vivo pig small bowel model using 2.0, 3.5, and 4.1mm unclosed staple heights with and without buttressing material. Burst pressures were related to staple height with greater staple heights being associated with a greater burst pressure. Improvements in burst pressure were associated with the use of reinforcement agents.

Assalia et al[14] employed bovine pericardial strips in performing sleeve gastrectomies in 18 pigs with a 3.8mm staple height. There was one subclinical staple line leak in the PS group. There was no significant difference in operating time, intra-operative blood loss, or staple line burst pressure. When the pigs were sacrificed two weeks postoperatively, there was increased inflammation and adhesion formation in the group in which PSDVCM was used.
These animal and ex-vivo studies demonstrate that reinforcement agents, when tested immediately after the staple lines have been formed, ensure a greater burst pressure than staples alone.[2,13,14] These findings are shared by the animal and cadaveric studies previously described, which examined the effects of staple height on burst pressures. Interestingly, the study involving pigs undergoing sleeve gastrectomy, where burst pressures were measured at two weeks,[14] showed no significant differences between those with and without a reinforcement agent and are consistent with the difficulties experienced in demonstrating that these experimental benefits actually translate into significant differences in outcome when applied in the clinical setting.

CLINICAL STUDIES INVOLVING STAPLE LINE REINFORCEMENT AGENTS
Nguyen et al[15] employed SGB in an uncontrolled case series of 44 patients undergoing a number of gastrointestinal (GI) procedures, which led to no need to oversew the staple line for bleeding, returns to theater for bleeding, or anastomotic leaks. Shikora et al[16] used PS in the formation of the gastric pouch on a consecutive series of 250 patients undergoing gastric bypass comparing results with 100 historic controls. There were two staple line leaks and one gastrocutaneous fistula in patients without PS and three gastrocutaneous fistulas in those with PS. Bleeding was not noted to be a problem in those patients with PS, although information on intra-operative bleeding was not available in historical controls.

Miller and Pump[17] conducted a small study with 24 patients in each arm. SGB was used with stapling devices during pouch formation in one group. Significantly fewer clips were needed in the SGB group to secure bleeding vessels, while their operating time was significantly shorter and postoperative hemoglobin significantly higher. One patient in the non-SGB group had a leak on intraoperative leak testing and three patients developed gastrocutaneous fistula. These results contrast somewhat with those of Nguyen[15] who had three gastrocutaneous fistulas in patients where a reinforcement agent was employed.

Shikora et al[16] compared three reinforcement agents, SGB, PS, and PSDVCM. There were no significant differences in the degree of bleeding between agents with all four contained anastamotic leaks occurring in patients in whom SG was employed. With 145 of the 1,451 patients undergoing operations with SG, these events were statistically significant.

Consten et al[19] undertook a prospective study of 20 patients undergoing sleeve gastrectomy with SGB and 10 without, as part of a duodenal switch. There was significantly greater blood loss in the patients who had no SGB (210 vs. 120mL). There were two staple-line hemorrhages and a subphrenic abscess in those where SGB was not used. In contrast, Kasilicky et al20 performed 61 sleeve gastrectomies employing 60cm blue cartridges without staple-line reinforcement or suturing and reported no leaks. Nocca et al[21] reported 163 sleeve gastrectomies. Nine patients developed leaks with six patients developing gastrocutaneous fistulas (four of these were following revision procedures). Green or gold cartridges were used and the staple line was reinforced with a running buttress suture or SGB. A review of sleeve gastrectomies in Germany[22] demonstrated a leak rate of seven percent in 144 patients and 42.6 percent in patients who had a buttress material employed with the staple line. Uglioni et al[23] reviewed 74 patients who had their staple line oversewn. There were no leaks, although one patient had dysphagia caused by excessive narrowing of the tube due to oversewing.

Chen et al[24] performed a meta-analysis of buttressing materials, including 11 articles on staple-line leakage. They noted that there was an increased risk of anastomotic leaks in patients who had reinforcement agents used in their surgery, but also suggested that, in order to demonstrate a reduction in anastomotic leak rates from 1.0 to 0.5 percent, it would be necessary to have a study group containing 9,346 patients. This, therefore, raises the question as to a validity of any differences in anastomotic leak rates demonstrated in smaller studies.

Comparison of 25mm circular stapled gastrojejunal anastomoses with and without the use of SGB led to a slight reduction in the incidence of staple-line leaks and bleeding but a highly significant reduction in the incidence of anastomotic strictures (0.7 vs. 9.3%) where SGB was used.[18] However, 31 percent of patients develop strictures at the gastrojejunal anastomosis—an unusually high proportion.[25]

Interestingly, Saber et al[26] compared staple-line reinforcement with SGB with intraluminal reinforcement with the same material. There was a trend to a reduction in the incidence of bleeding and anastomotic stricture in the group with intraluminal reinforcement.

OTHER STRATEGIES TO PREVENT STAPLE LINE LEAKS
Sapala et al[27] applied fibrin sealant (FS) to the gastrojejunal anastomosis of 738 patients undergoing micropouch gastric bypass with 1,120 historic controls. There were no anastomotic leaks or gastrogastric fistulas in the FS group, although there were two leaks from other sites requiring reoperation, compared with 11 (0.9%) leak rate in the historic controls. These differences were not significant.

Silecchia et al[28] undertook a study to examine whether FS applied to the gastrojejunal and jejunjejunal anastomoses reduced the risk of anastomotic leak and whether the glue could be used to occlude Peterson’s space and prevent internal hernias. One-hundred eleven patients received conventional surgery alone and 93 received conventional surgery and fibrin glue. There were no leaks or internal hernias in those who had fibrin glue while two patients in the groups undergoing conventional surgery alone underwent further surgery for anastomotic leaks. Sillechia et al[28] also used FS to reinforce their staple lines and close mesenteric spaces in a randomized, controlled trial involving 160 patients in each arm. While there were more anastomotic leaks on the control group and a higher reoperation rate in the control group, this difference did not reach statistical significance.
Where a leak occurs, it may be possible to close the defect employing sutures butressed with SGB pledgets.[29]

INTRAOPERATIVE LEAK TESTING
The American Society for Metabolic and Bariatric Surgery (ASMBS) issued a position statement on the prevention and detection of intraoperative gastrointestinal leak after RYGB.[30] The document states that intraoperative testing using a dye, air, or other gas may be useful in detecting and repairing defects in the anastomoses or staple lines, although they have not proven to be of value in reducing the overall leak rate. Klingman[31] performed pneumatic air testing of the gastrojejunal anastomosis in 257 patients undergoing RYGB. The site of an air leak was identified and repaired in 13 (5.1%) patients. None of these patients subsequently developed leaks. Similarly, Fullum et al[32] noted leaks in four of 760 patients undergoing RYGB. None developed leaks postoperatively. It is difficult to imagine that these patients did not benefit from the leak test even if leak testing has not been demonstrated to be of clinical value in studies.

SUMMARY AND CONCLUSIONS
While laboratory and animal studies have demonstrated the benefit of selecting the correct staple heights and the benefits of staple-line reinforcement agents in increasing staple-line burst pressures, clinical studies have failed to consistently translate these findings into demonstrable benefits in the clinical setting. The use of staple-line reinforcement agents reduce intraoperative blood loss. It is less clear whether such reduction is of clinical significance.

There is great variability in the practice of surgeons with regard to the selection of staple height and the usage of reinforcement agents or oversewing of staple lines or anastomoses. Some surgeons have not used buttressing material but have achieved excellent results with no or few complications. There appears to be only minimal differences in the anastomotic leak rates of studies examining the use of reinforcement agents. This may be attributed to the quality of the products employed, which are able to work well across a range of circumstances, as well as to the proper use of these products. Some of these differences may also be due to the failure of the power of the studies to be able demonstrate differences. In light of this, it is difficult to recommend the use of any particular staple height or reinforcement agents. It may be that some of the answers regarding leak rates with various staple heights and reinforcement agents in primary and revision bariatric surgery will become available when the data contained in the National Bariatric Surgery Registry  are analyzed.

REFERENCES
1.    Podnos YD, Jimenez JC, Wilson SE, et al. Complications after laparoscopic gastric bypass: a review of 3464 cases. Arch Surg. 2003;138(9):957–961.
2.    Baker RS, Foote J, Kemmeter P, et al. The science of stapling and leaks. Obes Surg. 2004;14(10):1290–1298.
3.    Nguyen NT, Rivers R, Wolfe BM. Early gastrointestinal hemorrhage after laparoscopic gastric bypass. Obes Surg. 2003;13(1): 62–65.
4.    Mehran A, Szomstein S, Zundel N, Rosenthal R. Management of acute bleeding after laparoscopic Roux-en-Y gastric bypass. Obes Surg. 2003;13(6):842–847.
5.    Sanchez H, Cabrera A, Cabrera K, et al. Laparoscopic Roux-en-Y Gastric Bypass as a Revision Procedure after Restrictive Bariatric Surgery. Obes Surg. 2008;18(12):1539–1543. Epub 2008 Aug 29.
6.    Champion JK, Williams MD. Prospective randomized comparison of linear staplers during laparoscopic Roux-en-Y gastric bypass. Obes Surg. 2003;13(6):855–859; discussion 860.
7.    El-Hakim A, Cai Y, Marcovich R, Pinto P, Lee BR. Effect of Endo-GIA vascular staple size on laparoscopic vessel sealing in a porcine model.  Surg Endosc. 2004;18:961–963.
8.    Zilling T, Walther BS. Are intersecting staple lines a hazard in intestinal anastomosis? Dis Colon Rectum. 1992;35(9):892–896.
9.    Zilling TL, Walther BS, Ranstam J. Intersecting staple lines and blood flow in oesophagojejunal anastomoses. Br J Surg. 1990; 77(12):1375–1378.
10.    Gonzalez R, Nelson LG, Gallagher SF, Murr MM. Anastomotic leaks after laparoscopic gastric bypass. Obes Surg. 2004;14(10):1299–1307.
11.    Consten EC, Dakin GF, Gagner M. Intraluminal migration of bovine pericardial strips used to reinforce the gastric staple-line in laparoscopic bariatric surgery. Obes Surg. 2004; 14(4):549–554.
12.    Arnold W, Shikora SA. A comparison of burst pressure between buttressed versus non-buttressed staple-lines in an animal model. Obes Surg. 2005;15:164–171.
13.    Mery CM, Shafi BM, Binyamin G, Morton JM, Gertner M. Profiling surgical staplers: effect of staple height, buttress, and overlap on staple line failure. Surg Obes Relat Dis. 2008;4(3):416–422.
14.    Assalia A, Ueda K, Matteotti R, et al. Staple-line reinforcement with bovine pericardium in laparoscopic sleeve gastrectomy: experimental comparative study in pigs. Obes Surg. 2007;17:222,228.
15.    Nguyen NT, Longoria M, Chalifoux S, Wilson SE. Bioabsorbable staple line reinforcement for laparoscopic gastrointestinal surgery. Surg Technol Int. 2005;14:107–111.
16.    Shikora SA, Kim JJ, Tarnoff ME. Comparison of permanent and nonpermanent staple line buttressing materials for linear gastric staple lines during laparoscopic Roux-en-Y gastric bypass. Surg Obes Relat Dis. 2008;4(6):729–734.
17.    Miller KA, Pump A. Use of bioabsorbable staple reinforcement material in gastric bypass: a prospective randomized clinical trial. Surg Obes Relat Dis. 2007;3(4):417–421; discussion 422. Epub 2007 Jun 12.
18.    Jones WB, Myers KM, Traxler LB, Bour ES. Clinical results using bioabsorbable staple line reinforcement for circular staplers. Am Surg. 2008;74(6):462–467.
19.    Consten EC, Gagner M, Pomp A, Inabnet WB. Decreased bleeding after laparoscopic sleeve gastrectomy with or without duodenal switch for morbid obesity using a stapled buttressed absorbable polymer membrane. Obes Surg. 2004;14(10):1360–1366.
20.    Kasalicky M, Michalsky D, Housova J, et al. Laparoscopic sleeve gastrectomy without an over-sewing of the staple line. Obes Surg. 2008;18(10):1257–1262
21.    Nocca D, Krawczykowsky D, Bomans B, et al. A prospective multicenter study of 163 sleeve gastrectomies: results at 1 and 2 years. Obes Surg. 2008;18, 560–565.
22.    Stroh C, Birk D, Flade-Kuthe R, et al; Bariatric Surgery Working Group. A Nationwide Survey on Bariatric Surgery in Germany—Results 2005–2007. Obes Surg. 2009;19:105–112.
23.    Uglioni B, Wölnerhanssen B, Peters T, et al. Midterm results of primary vs. secondary laparoscopic sleeve gastrectomy (LSG) as an isolated operation. Obes Surg. 2009;19(4):401–406. Epub 2009
Jan 24.
24.    Chen B, Kiriakopoulos A, Tsakayannis D, et al. Reinforcement does not necessarily reduce the rate of staple line leaks after sleeve gastrectomy. A review of the literature and clinical experiences. Obes Surg. 2009;19(2):166–172.
25.    Jones WB, Myers KM, Traxler LB, Bour ES. Clinical results using bioabsorbable staple line reinforcement for circular staplers. Am Surg. 2008;74(6):462–467; discussion 467–468.
26.    Saber AA, Scharf KR, Turk AZ, Elgamal MH, Martinez RL. Early experience with intraluminal reinforcement of stapled gastrojejunostomy during laparoscopic Roux-en-Y gastric bypass. Obes Surg. 2008;18(5):525–529.
27.    Sapala JA, Wood MH, Schuhknecht MP. Anastomotic leak prophylaxis using a vapor-heated fibrin sealant: report on 738 gastric bypass patients. Obes Surg. 2004;14(1):35–42.
28.    Silecchia G, Boru CE, Mouiel J, et al. The use of fibrin sealant to prevent major complications following laparoscopic gastric bypass: results of a multicenter, randomized trial. Surg Endosc. 2008;22(11):2492–2497.
29.    Basu NN, Leschinskey D, Heath DI. The use of Seamguard to buttress the suture repair of a staple line leak following laparoscopic gastric bypass for obesity. Obes Surg. 2008;18(7):896–897.
30.    American Society for Metabolic and Bariatric Surgery. ASMBS position statement on prevention and detection of gastrointestinal leak after gastric bypass including the role of imaging and surgical exploration. January 2009. http://www.asmbs.org/Newsite07/resources/leak_management_position.pdf. Access date: October 28, 2009.
31.    Kligman MD. Intraoperative endoscopic pneumatic testing for gastrojejunal anastomotic integrity during laparoscopic Roux-en-Y gastric bypass. Surg Endosc. 2007;21(8):1403–1405.
32.    Fullum TM, Aluka KJ, Turner PL. Decreasing anastomotic and staple line leaks after laparoscopic Roux-en-Y gastric bypass. Surg Endosc. 2009;23(6):1403–1408.

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