How reliable is intracorporeal laparoscopic knot tying?

Risk identification and technical modifications reduce the incidence of post-cholecystectomy bile leakage: analysis of 5675 laparoscopic cholecystectomies

PURPOSE

The main sources of post-cholecystectomy bile leakage (PCBL) not involving major duct injuries are the cystic duct and subvesical/hepatocystic ducts. Of the many studies on the diagnosis and management of PCBL, few addressed measures to avoid this serious complication. The aim of this study was to examine the causes and mechanisms leading to PCBL and to evaluate the effects of specific preventative strategies.

METHODS

A prospectively maintained database of 5675 consecutive laparoscopic cholecystectomies was analysed. Risk factors for post-cholecystectomy bile leakage were identified and documented and technical modifications and strategies were adopted to prevent this complication. The incidence, causes and management of patients who suffered bile leaks were studied and their preoperative characteristics, operative data and postoperative outcomes were compared with patients where potential risks were identified and PCBL avoided and with the rest of the series.

RESULTS

Twenty-five patients (0.4%) had PCBL (7 expected and less than half requiring reintervention): 11 from cystic ducts (0.2%), 3 from subvesical ducts (0.05%) and 11 from unconfirmed sources (0.2%). The incidence of cystic duct leakage was significantly lower with ties (0.15%) than with clips (0.7%). Fifty-two percent had difficulty grades IV or V, 36% had empyema or acute cholecystitis and 16% had contracted gallbladders. Twelve patients required 17 reinterventions before PCBL resolved; 7 percutaneous drainage, 6 ERCP and 4 relaparoscopy. The median hospital stay was 17 days with no mortality. Hepatocystic ducts were encountered in 72 patients (1.3%) and were secured with loops (54.2%), ties (25%) or sutures (20.8%) with no PCBL. Eighteen sectoral ducts were identified and secured.

CONCLUSION

Ligation of the cystic duct reduces the incidence of PCBL resulting from dislodged endoclips. Careful blunt dissection in the proper anatomical planes avoiding direct or thermal injury to subvesical and sectoral ducts and a policy of actively searching for hepatocystic ducts during gallbladder separation to identify and secure them can reduce bile leakage from such ducts.

In Vivo Comparison of MONOFIX, A Novel Barbed Suture with a Triangular Stopper, with Pre-existing Products in a Porcine Model

STUDY OBJECTIVE

MONOFIX, a new absorbable barbed suture device, has a triangular stopper at the end to hold the suture to the tissue without hooking the looped end or knotting. The aim of this study was to compare the biomechanical strength and histologic features of MONOFIX with other barbed suture devices using a porcine model.

DESIGN

Well-designed, controlled trial without randomization.

SETTING

Animal laboratory in university hospital.

SUBJECTS

Sixteen, 60-kg, mature female domestic pigs (skin closure group) and 5, 60-kg, mature female domestic pigs (fascial closure group).

INTERVENTIONS

In the skin closure group, 3-0 MONOFIX versus 2 widely used 3-0 absorbable barbed sutures (3-0 V-Loc 180 or Stratafix). In the fascial closure group, 2-0 MONOFIX versus 1 widely used 2-0 absorbable barbed sutures (2-0 Stratafix).

MEASUREMENTS AND MAIN RESULTS

In the skin closure group, the biomechanical wound strength of skin sutured with size 3-0 MONOFIX, V-Loc 180, or Stratafix was evaluated by postoperative day assessment (days 0, 3, 7, 14, and 28). In the fascial closure group, pigs underwent 2 paramedian incisions and were sutured with 2-0 MONOFIX or with 2-0 Stratafix to evaluate histologic reaction. At 6 weeks the tissues around the suture line were excised and microscopically evaluated. The biomechanical strength of the MONOFIX had similar tissue tensile strength compared with the control, regardless of postoperative day. In the fascial closure model, there was no significant difference in the average tissue reaction score between MONOFIX and Stratafix (1.2 ± .3 vs 1.3 ± .3, p = .478).

CONCLUSION

This study demonstrated that MONOFIX has equivalent tensile strength and histologic reaction when compared with commonly used barbed suture devices. Accordingly, this preclinical study suggests that the use of MONOFIX is a safe alternative to other barbed suture devices.

One-handed knot tying technique in single-incision laparoscopic surgery

In an open surgery, two-handed as well as one-handed knot tying is commonplace. Knot tying in laparoscopic surgery traditionally involves the use of two instruments (for fashioning an intracorporeal knot) or passing of a ligature around a tubular structure, exteriorising it, fashioning a knot, and sliding it down with a knot-pusher (external slip knot). With increasing interest in expanding applications of single-incision laparoscopic surgery (SILS), surgeons are faced with new challenges. In SILS it is not usually possible to utilise two instruments for knot tying as they lie almost parallel. We describe a novel one-handed knot tying technique devised specifically for use in SILS.

Optimal tissue tension for secure laparoscopic knots

Security and strength of a knot are main concerns of the surgeon since last 4000 years. The advancement of endoscopic and minimally invasive surgery in last few decades had a significant influence on a knot tying. The most difficult methods of a knot tying are performed during endoscopic procedures, in which the surgeon execute instrumentation from outside the body without palpation of organs and three-dimensional vision. In addition, laparoscopic instruments due to friction in transmission mechanism have very poor force feedback. This results into difficulty in applying the appropriate grasping force to the tissue, resulting in slippage or damage to the tissue. Our hypothesis highlights the need of tissue approximation at the 'optimum tissue tension' sufficient to resist the slippage of suture/clip without strangulation. The purpose of suture is to maintain an approximation of the tissue until healing progresses to the point where artificial support is no longer necessary for the wound to resist normal stress. When the approximation is too tight, tension in tissue leads to diminished blood supply resulting into the necrosis. Various tissues need different blood supply and different tissue pressure for optimum healings. Proposed hypothesis helps to improve the feedback of current knot pushers or clip applicators used in laparoscopic surgery using optimum tissue tension. Tissue approximation at an optimal tissue tension translates into the secure laparoscopic knot/clip application resulting in prevention of wound dehiscence, anastomosis leak, and secondary haemorrhages.