Kumar versus Olsen cannulation technique for intraoperative cholangiography: a randomized trial

Area of Science:

• Gastroenterology and Hepatobiliary Surgery
• Surgical Innovation
• Minimally Invasive Procedures

Background:

• Routine intraoperative cholangiography (IOC) faces resistance due to prolonged surgical times and perceived difficulty.
• Alternative instruments aim to simplify IOC and encourage its wider adoption during cholecystectomy.
• The KOALA trial investigated the Kumar cannulation technique against the standard Olsen clamp for IOC.

Purpose of the Study:

• To compare the Kumar cannulation technique with the Olsen clamp for intraoperative cholangiography (IOC) during laparoscopic cholecystectomy.
• To evaluate differences in procedure time and perceived ease of use between the two IOC methods.
• To determine if the Kumar clamp offers advantages over the Olsen clamp in simplifying IOC.

Main Methods:

• Elective laparoscopic cholecystectomy patients were randomized to IOC using either the Kumar or Olsen clamp.
• Primary endpoints included IOC procedure duration and surgeon-assessed ease of use (visual analog scale 0-10).
• A sample size of 40 patients was calculated to detect a 33% difference in IOC time.

Main Results:

• The study included 59 patients, with 28 randomized to the Kumar clamp and 22 to the Olsen clamp for IOC.
• Success rates were comparable: 82.1% for Kumar clamp and 86.4% for Olsen clamp (p > 0.999).
• Mean IOC time was 10 min 27 sec (Kumar) vs. 11 min 34 sec (Olsen) (p = 0.537), with perceived ease rated identically (6.8 for both).

Conclusions:

• The Kumar cannulation technique offers no significant advantage in speed or ease of use over the Olsen clamp for IOC.
• Both the Kumar and Olsen clamps facilitate intraoperative cholangiography in approximately 10 minutes.
• The choice between the Kumar and Olsen clamps for IOC should be based on individual surgeon preference.