Vascular control during laparoscopic kidney donation.

SUMMARY: Laparoscopic donor nephrectomy (LDN) is the gold standard for kidney donation. Recent literature has led to considerable debate regarding the safest route to provide vascular control during this procedure. The most common devices used for vascular control during LDN are staplers and surgical clips. Opinions regarding the safety of these devices vary, as both are prone to dysfunction. Certain clips have already been contraindicated for use on the donor artery owing to reports of catastrophic complications of falling off. Donor safety is paramount to the continued success of renal transplantation in Canada. A review of existing practice at each institution may be called for to ensure the safest standards possible are in place. An appendix to this commentary is available at canjsurg.ca.

The unacknowledged incidence of laparoscopic stapler malfunction.

BACKGROUND: Laparoscopic instruments are being used with increasing frequency. Our surgeons recently experienced several independent adverse events involving the laparoscopic linear stapler. Although the Food and Drug Administration maintains a Manufacturer and User Facility Device Experience (MAUDE) database to track such voluntary reports, many events are not reported and the true incidence of adverse events is unknown. We attempted to determine how frequently minimally invasive surgeons have experienced technical problems with a laparoscopic stapler. METHODS: Following IRB approval, we electronically distributed an anonymous 10-question survey to the 124 minimally invasive program directors listed in the Fellowship Council database. The questions focused on personal or peer experience with laparoscopic stapler malfunction, frequency and type of malfunction, device manufacturer, whether the operation was altered, and root cause analysis of the event. RESULTS: Forty-four of the 124 program directors (35%) completed the survey. The majority reported personal or peer experience (86%) with a linear stapler not releasing (66%) or not firing (73%) after application, with 27% of the respondents noting that this occurred three or more times. The malfunction was not related to type of load, straight (23%) or reticulating (32%) model, or manufacturer (Ethicon 30%, Covidien 36%). One quarter of the respondents noted that the malfunction caused them to significantly alter their operative procedure, and 30% reported that they received no helpful feedback from the manufacturer despite contacting it. CONCLUSIONS: Most minimally invasive surgeons have experienced laparoscopic linear stapler malfunction and 25% have had to significantly alter the planned operative procedure due to the malfunction.

Improving safety and efficiency during emergent central venous catheter placement with a needleless securing clamp.

OBJECTIVE: To compare the needleless securing clamp to the traditional suture-secured clamp for central venous catheters. METHODS: Compare the holding strength of each type of clamps by measuring the amount of kinetic energy absorbed, ask 20 physicians to evaluate the clamp placement using sutures or staples, and summarise the clamps effectiveness and complications in 10 patients. RESULTS: Compared to sutured clamp, the needleless clamp was more secure. The needleless clamp was also significantly better with regard to ease of use, safety, perceived strength (p value <0.002), and insertion time was reduced by 63%. No adverse events or skin infections occurred while using the needleless clamps. CONCLUSIONS: Without incurring complications or increasing risk to patients, the needleless clamp is secure and improves safety and efficiency for physicians.

Comparative study of a barbed suture, poliglecaprone and stapler in Pfannenstiel incisions performed for benign gynecological procedures: a randomized trial.

OBJECTIVE: To compare a novel barbed suture, poliglecaprone-25 suture and stapler in Pfannenstiel incisions performed for benign gynecological procedures. DESIGN: A randomized controlled non-inferiority trial with randomization in a 1:1:1 ratio. SETTING: Istanbul Dr. Lutfi Kirdar Kartal Research and Training Hospital, Department of Obstetrics and Gynecology. POPULATION: Patients between 18 and 45 years of age without prior lower abdominal incision and undergoing Pfannenstiel incisions for benign gynecological procedures. METHODS: A total of 117 female patients randomized into barbed (n = 39), poliglecaprone-25 (n = 39) and stapler (n = 39) groups according to suture type. Skin closure techniques were compared in terms of length of incision (cm), adverse events (wound dehiscence, incisional infection, seroma and hematoma), subjective pain scores, patient satisfaction and postoperative scar cosmesis. MAIN OUTCOME MEASURES. The difference between three suture materials in terms of postoperative incision pain, patient satisfaction and scar cosmesis. RESULTS: Skin closure techniques were similar in terms of length of incision (cm), adverse events and pain scores and Modified Hollander Cosmesis Score. Barbed (p < 0.001) and poliglecaprone-25 (p < 0.01) sutures were significantly better than staplers in terms of patient satisfaction. CONCLUSION: The three different methods of skin closure revealed comparable outcome except for a significant superiority of sutures to the stapler method in terms of patient satisfaction scores.

Improving the side-to-side stapled anastomosis: comparison of staplers for robust crotch formation.

BACKGROUND: Few studies have investigated the burst pressure of side-to-side anastomoses comparing different stapling devices that are commercially available. OBJECTIVES: We conducted side-to-side anastomoses with a variety of staplers and compared burst pressure in the crotch of the anastomoses. SETTING: Nagoya City East Medical Center. METHODS: We conducted side-to-side anastomoses with 9 staplers with different shapes and forms. Fresh pig small intestines were used. A side-to-side anastomosis was performed between 2 intestine specimens using a linear stapler. The burst pressure of the anastomosis was recorded. RESULTS: In total, 45 staplers were used for this experiment. The site of leakage in all cases was the crotch. Regarding the influence of the number of staple rows, the burst pressure in 3-row staplers was significantly higher than in 2-row staplers. With regard to the relationship between staple height and burst pressure, staples with a height slightly shorter than the intestinal thickness showed the highest burst pressure. In a comparison of staplers with uniform staple heights and stamplers with staples of 3 different heights, the latter had significantly lower burst pressures. Neoveil significantly increased the burst pressure in the crotch and contributed to the highest burst pressure of all the staplers used in this experiment. CONCLUSIONS: In this experiment, we defined the important factors that influence burst pressure at the crotch of a stapled, side-to-side anastomosis. These factors include the number of staple rows, the height of the staple compared with the thickness of the tissue, uniformity of staple height, and reinforcement of the staple line. In any surgical case requiring intestinal anastomosis, selection of a stapler is a critical step.

Concept design and simulation study on a "phantom" anvil for circular stapler.

INTRODUCTION: Complications and challenges arising from the intraoperative double-stapling technique are seldom reported in colorectal surgery literature. Partial or full-thickness rectal injuries can occur during the introduction and the advancement of the circular stapler along the upper rectum. The aim of this study is to address some of these issues by designing and optimizing a "phantom" anvil manufactured to overcome difficulties throughout the rectal introduction and advancement of the circular stapler for the treatment of benign and malignant colon disease. METHODS: The design of the "phantom" anvil has been performed using computer-aided modeling techniques, finite element investigations, and 2 essential keynotes in mind. The first one is the internal shape of the anvil, which is used for the connection to the gun. The second is the shape of the cap, which makes possible the insertion of the gun through the rectum. The "phantom" anvil has 2 functional requirements, which have been taken into account. The design has been optimized to avoid colorectal injuries, neoplastic dissemination (ie, mechanical seeding) and to reduce the fecal contamination. RESULTS: Numerical simulations show that a right combination of both top and bottom fillet radii of the shape of the anvil can reduce the stress for the considered anatomic configuration of >90%. Both the fillet radii at the top and the bottom of the device influence the local stress of the colon rectum. CONCLUSIONS: A dismountable device, which is used only for the insertion and advancement of the stapler, allows a dedicated design of its shape, keeping the remainder of the stapler unmodified. Computer-aided simulations are useful to perform numerical investigations to optimize the design of this auxiliary part for both the safety of the patient and the ease of the stapler advancement through the rectum.

Prospective comparative evaluation of stapled versus transected silastic ring gastric bypass: 6-year follow-up.

BACKGROUND: The effect of transecting vs. stapling the stomach in continuity in the banded gastric bypass (GBP) operation was studied. METHOD: 50 patients, 25 in each group, were enrolled into a prospective study to determine if transecting the stomach vs. stapling it in continuity in performing GBP for obesity decreases the incidence of gastro-gastric fistula formation without increased morbidity. RESULTS: The patient profiles in the 2 groups were very similar. The peri-operative complications included 1 splenic capsular injury in each group, controlled without a splenectomy. There was 1 anastomotic leak in the stapled and 1 bleeding from the cut edge of the bypassed stomach in the transected group, both requiring re-operations in the immediate postoperative period. There was no peri-operative mortality. The percent follow-up after 6 years was 80% and 88% in the stapled and transected groups respectively. The incidence of late complications of solid food intolerance, ventral incisional hernia, cholelithiasis and small bowel obstruction was similar in both groups. There were 8 gastro-gastric fistulas in the stapled group and 1 in the transected group. The reduction in body mass index and percent excess weight loss (66%) were similar in both groups. CONCLUSION: The incidence of gastro-gastric fistula may be reduced in GBP procedures by transecting the stomach as opposed to stapling it in continuity, without an increase in morbidity or mortality or any loss in the effectiveness of the operation.

New techniques of gastrointestinal anastomoses using the EEA stapler.

A new instrument for performing end-to-end, inverted stapled anastomoses in the gastrointestinal tract is described. Its advantages and disadvantages are also discussed. Techniques to avoid a proximal enterotomy or colotomy are described in Billroth I gastrectomy and end-to-side ileocolostomy, and experience with 30 anastomoses, their hazards, and complications are reported. The instrument creates a better anastomosis and shortens the operative time.

Circular anastomosis stapler. An alternative to pursestring suture.

When used with the circular anastomosis stapler, the pursestring suture (PSS) is not always secure, primarily due to esophageal fragility and secondarily due to poor operative exposure. This problem prompted us to develop a simple, rapid technique to replace the PSS. It consists of a total circular ligature of the esophageal wall, which is tightened around the axis of the stapler between the anvil and cartridge. Exposure of the esophagus and introduction of the device are easily done. Anastomosis reliability was shown by the absence of postoperative complications caused by anastomotic leakage in more than 200 consecutive patients.

Temporary double exclusion of the perforated esophagus using absorbable staples.

A new method for double exclusion of the esophagus is presented. Temporary closure of the cervical and intraabdominal esophagus using absorbable staples allows effective healing of esophageal perforations. The procedure should be routinely combined with drainage of the periesophageal abscess. Complete recanalization of the esophagus occurs 1 to 2 weeks after operation.

Clinical efficacy of the stapled anastomosis in esophageal reconstruction.

We have clinically evaluated Russian and American stapling devices used for esophageal reconstruction and compared the results following stapled anastomosis with those following hand-sutured procedures, both performed by the same surgeon. With the Russian stapler, anastomoses performed in 17 patients with carcinoma of the thoracic esophagus resulted in only one (5.9%) anastomotic leak; in 12 hand-sutured anastomoses and in 11 anastomoses done with an American stapler, no anastomotic complication occurred. Thus, a long gastric tube with good blood supply is of paramount importance, and if the technical details of surgical stapling can be overcome, a stapled anastomosis appears to be as safe as a manual suturing for patients undergoing esophageal reconstruction.

Use of circumferential stapler in reconstruction following resections for carcinoma of the cardia.

The use of the End-to-End Anastomosis (EEA) circumferential stapler for reconstruction following resection of the esophagus and stomach for carcinoma of the cardia is reported here in 9 consecutive patients with fifteen anastomoses performed with this unit. The technical aspects of the EEA stapler are emphasized. Two frequent problems associated with this type of operation namely, stenosis or leak at the suture line, are completely avoided by the use of this stapler unit. Its use is recommended.

Experience with the EEA stapling device.

The EEA stapling instrument was used to perform 48 anastomoses without operative mortality. One of the 29 colorectal anastomoses developed a leak. Two intraabdominal abscesses were noted, one after an intraperitoneal colocolostomy and one after a colorectal anastomosis. No leaks were demonstrated in the 12 esophageal anastomoses. Minor bleeding that occurred in one of the colorectal anastomoses ceased spontaneously without need for transfusion. One esophageal and one colorectal anastomosis became narrowed postoperatively, but both were corrected with dilatation without further problem. In two of the very low colorectal anastomoses, transient fecal soilage occurred for 4 to 5 months postoperatively. On the basis of our experience, we believe that the EEA instruments has a definite place in gastrointestinal surgery. Its greatest virtue is that it provides a means to perform the heretofore technically difficult and frequently insecure colorectal and esophageal anastomoses with greater facility and security.

Evaluation of the safety of end-to-end (EEA) stapling anastomoses across linear stapled closures.

An experimental study involving circular stapled anastomoses across linear stapled closures is presented. Although the staples were deformed, cut in two, and sometimes uninjured, no complications were found. These data support the use of this technique, which is currently employed in clinic practice.

Pullout strength of power- and hand-driven staples in synthetic bone: effect of design parameters.

The pullout strength of power-driven and hand-driven staples of different sizes and different leg profiles was investigated in a synthetic bone model. Consistent material properties were reflected in the relatively small standard deviation in pullout strength, which was less than 7% of the mean value for power-driven and less than 10% of the mean value for hand-driven staples. An approximate linear relationship was shown to exist between the mean value of pullout strength and foam density. In paired studies, the mean value of pullout strength was significantly (p less than 0.0005) greater for the power-driven staples than similar size hand-driven staples. It was also shown that a square cross section creates significantly (p less than 0.017) more resistance to pullout force than a circular section of similar or even larger area. Although the pullout strength was not a function of the staple's width, the staple's leg length contributed to its pullout strength in a nonlinear fashion. This study suggests that narrow, long, power-driven staples of rectangular cross section have the best pullout strength for similar cross-sectional area.

Laparoscopic clips. Evaluation of absorbable and titanium with regard to hemostasis and tissue reactivity.

Advanced laparoscopic techniques require laparoscopic means of providing hemostasis. We tested the hemostatic ability of laparoscopic surgical clips and their tissue reactivity as assessed by adhesion formation in an animal model. Twenty-six New Zealand white rabbits were randomized at laparotomy to one of three treatment groups: titanium surgical clips, absorbable surgical clips (both applied with a laparoscopic clip applicator) and chromic sutures of equal mass. Either the right fallopian tube was transected, with clips or sutures applied proximally and distally to control bleeding, or the clips or sutures were applied 5 mm apart and the tube transected. A clip or suture of the same material was placed on the midportion of the left fallopian tube. Necropsy was performed at 42 days, and each clip/suture site was scored for adhesions. All the materials were easily applied and effective in achieving hemostasis. The adhesion scores tended to be lower with the absorbable clips; however, there were no statistically significant differences between the groups. Laparoscopic clips are effective in providing hemostasis, are easily applied and cause no more adhesion formation than do conventional suture materials.

Stapled anastomosis in esophageal resections with Chinese staplers: a retrospective study of 1965 consecutive cases.

OBJECTIVES: To investigate the safety and efficacy of mechanical anastomosis with Chinese staplers in the surgical treatment of esophageal carcinoma and carcinoma of gastric cardia in order to find out an alternative effective anastomotic technique to hand-sewn method. METHODS: From August 1980 to April 1996, there were totally 1264 cases of esophageal carcinoma and 701 cases of carcinoma of gastric cardia receiving esophagogastric anastomosis with Chinese staplers combined with telescope suturing of seromuscular layers after resection of tumors, with age ranging from 28 years to 81 years and a man to woman ratio of 4:1 (1572/393). The anastomosis was performed at the cervical region in 44 patients, and intrathoracically in 1921. Our technical essential points also included fixation of the gastric substitute to the thoracic apex or mediastinum with 3-4 stitches to relieve the anastomotic tension. RESULTS: Compared with the reported postoperative leakage rate from 2%-4% in China and 4.2%-12.3% abroad, our techniques reduced the total leakage rate to 0.8%, that is, cervical leakage rate was 11.4% (5/44), and intrathoracic leakage rate 0.57% (11/1921). The intrathoracic leakage rate was 0.99% (8/808) for the first 8 years, and 0.27% for the following 8 years. There was no leakage (0/350) in the last 3 years. There anastomotic stricture occurred in 98 patients (4.99%) which could be relieved by Bougie or balloon dilatation. The total operative mortality was reduced to 0.76%. CONCLUSIONS: Mechanical anastomosis with Chinese staplers combined with telescope suturing should be an effective method to prevent the occurrence of anastomotic leakage after esophageal resections.

[Circular staple anastomoses in the gastrointestinal tract with the staplers SPTU and EEA]. / Zirkuläre Klammeranastomosen im Magen-Darm-Trakt mit den Klammernahtgeräten SPTU and EEA.

In 72 patients, 80 circular stapler anastomoses have been performed in the whole gastrointestinal tract of them, 39 were created by means of the Russian SPTU stapler with a single row of staples and 41 were performed with the American Auto-Suture EEA stapler, which employs a double row of staples. Three patients died because of anastomotic leakage (4.17%) and one myocardial infarction (overall mortality: 5.56%). The use of circular staplers lowers the incidence of anastomotic dehiscence, shortens the operating time and enlarges the operative possibilities, particularly in esophageal and rectal surgery. Since application of these staplers may be difficult, this, like any other surgical technique, must be trained.

[DIN-oriented tensile strength evaluation of surgical tissue sutures]. / DIN-orientierte Festigkeitsprüfung chirurgischer Gewebeverbindungen.

Methods to determine the mechanical properties of surgical wounds and sutures are valuable tools in wound healing research. So far standardized testing procedures have not been defined in the surgical literature, which reduces the comparability of results from different authors. Therefore we suggest a modified tensile testing procedure which follows German industrial standards (DIN 53455). The experimental set-up includes an universal testing machine and special clamps. The dumbbell-shaped specimen consist of freshly prepared pig skin and the suture which is to be tested. Well-known mechanical properties of surgical sutures and wounds were used to approve the precision of the experimental set-up. Reproducible analysis of all tested sutures and wounds (n = 120) was possible. We recommend testing procedures adapted to industrial standards to obtain comparable results in determination of mechanical properties of surgical wounds and sutures.

A newly designed miniplate staple for high tibial osteotomy.

A biomechanical study was made to compare the mechanical performance of the newly designed Miniplate staple to the conventional Coventry staple in high tibial osteotomy (HTO). Using twenty fresh porcine tibiae, the fixational strength of the two different types of staples in HTO was compared. To minimize the error due to the specimen-to-specimen individuality, the bone mineral density of the tibiae was measured with bone densitometry and those with 0.8 to 1.2 gm/cm2 at the proximal tibia were used in the biomechanical test. Testing was performed on a material testing system with aid of a commercial data processor. Using two different loading modes, "pull-out" and "push-out," the maximum resistant force required to release the staple from the substrate bone was recorded. In the pull-out test, ten nonosteotomized specimens were used and the staple was pulled out by subjecting an axial tension on the head of the staple inserted. In the push-out test ten tibiae osteotomized in the usual method of HTO were used and the staple was not directly loaded. In this testing, as a mimic condition of the natural knee, the proximal part of the specimen tibia was pushed horizontally in order for the staple to be pulled out while the distal tibia was fixed. The pull-out strength of Coventry staple and Miniplate staple were found to be 27.88 +/- 5.12 kgf and 182.47 +/- 32.75 kgf, respectively. The push-out strength of Coventry staple and Miniplate staple were 18.40 +/- 4.47 kgf and 119.95 +/- 19.06 kgf, respectively. The result revealed that the Miniplate staple has both a pull-out and push-out strength that is more than six times higher than Coventry staple. Based on the data, it is believed that the Miniplate staple provides better postoperative fixation in HTO. The postoperative application of long leg casting may not be needed after HTO surgery.