Assessment of surgical trainees' quality of knot-tying.

BACKGROUND: This study aimed to assess surgical trainees' knot tying technique and determine the type and security of knots created. METHODS: Twenty-five participants were requested to tie 40 knots each, using Vicryl 2-0 and Prolene 2-0 sutures. With each suture material, the participants tied: in series 1, 4 knots as they would normally do during surgery; in series 2, 4 knots with 3 throws, 4 knots with 4 throws, 4 knots with 5 throws, and 4 knots with 6 throws. All knots were tested for tensile strength using a tensiometer. Knots with tensile strength of less than 5 N were considered dangerous. RESULTS: Of the 25 participants, 2 created square knots consistently, 2 created a mixture of square and slip knots, and 21 created only slip knots. Square knots accounted for only 12.8% of all the knots. The incidence of knot slipping under tension was significantly lower with square knots (p < 0.001). Square knots had significantly higher tensile strength than slip knots (p < 0.001). For Vicryl, 4-throw square knots were superior to 6-throw slip knots (p < 0.001). For Prolene, 3-throw square knots were superior to 6-throw slip knots (p = 0.035). Some 12.6% of Vicryl knots and 5.6% of Prolene knots were dangerous and all of these were slip knots with up to 6 throws. Three out of 12 participants who thought they had created square knots actually created square knots and the rest produced slip knots. The participants' surgical experience did not have any correlation with their knot security (r = -0.044, p = 0.833). CONCLUSIONS: Knot tying is often executed with technical errors resulting in slip knots with less than optimal security and high incidence of dangerous knots. Tensiometry testing could be used as an objective assessment tool for knot-tying competency for surgical trainees.

Randomized clinical trial of torsional versus linear mode ultrasonically activated devices for laparoscopic cholecystectomy.

BACKGROUND: Conventional ultrasonically activated devices use linear mode vibration. Torsional mode ultrasonically activated device (TM) that oscillate around an arc have been recently introduced in the hope that the design may result in faster cutting and better hemostasis. METHODS: Patients undergoing elective laparoscopic cholecystectomy were randomized to TM or linear mode ultrasonically activated device (LM). Intraoperative events were recorded. Postoperatively, a sample of suction fluid was analyzed for hemoglobin concentration to calculate intraoperative blood loss. RESULTS: Seventy-five patients were randomized to TM and 76 patients to LM. Median blood loss was 5 (interquartile range (IQR), 1-19.7) ml with TM and 10.5 (IQR, 2.3-23) ml with LM (p = 0.105). The 95% confidence interval for the difference in median operative blood loss was -1.3 to +9.5 ml. Median gallbladder dissection time was similar in both groups (17 (IQR 11-29) minutes for TM vs. 21 (IQR, 12-29) minutes for LM; p = 0.248). Other modalities of hemostasis were required in 14 patients (19%) in the TM group compared with 21 patients (28%) in the LM group. One patient in the LM group developed postoperative hemoperitoneum and required urgent laparoscopic exploration. No patient required blood transfusion or suffered any other significant complication. CONCLUSION: TM has similar effectiveness to LM for laparoscopic cholecystectomy. REGISTRATION NUMBER: ISRCTN87527062 ( http://www.controlled-trials.com ).

Comparison of early outcomes for laparoscopic ventral hernia repair between nonobese and morbidly obese patient populations.

BACKGROUND: Obesity predisposes to incisional herniation and increased the incidence of recurrence after conventional open repair. Only sparse data on the safety and security of laparoscopic ventral hernia repair (LVHR) for morbidly obese patients are available. This study compared the incidence of perioperative complications and early recurrence after LVHR between morbidly obese and non-morbidly obese patients. METHODS: The case records of consecutive patients who underwent LVHR between December 2002 and August 2007 were reviewed. Patients with a body mass index (BMI) lower than 35 kg/m2 were compared with morbidly obesity patients who had a BMI of 35 kg/m2 or higher. RESULTS: The study included 168 patients (87 men) with a median age of 55 years (range, 24-92 years). Two conversions to open repair (1.2%) were performed, both for non-morbidly obese patients. Of the 168 patients, 42 (25%) were morbidly obese (BMI range, 35.0-58.0 kg/m2) and 126 (75%) were non-morbidly obese (BMI range, 15.5-34.9 kg/m2). The groups showed no significant differences in age, gender, number or size of fascial defects, operative time, length of hospital stay, or incidence of perioperative complications. At a median follow-up period of 19 months (range, 6-62 months), 20 patients (12%) had recurrent hernias. The incidence of recurrence was significantly associated with the size of the fascial defect and the size of the mesh, but not with morbid obesity. CONCLUSION: No significant difference in the incidence of perioperative complications or recurrence after LVHR was observed between the morbidly obese patients and the non-morbidly obese patients.