The HAC trial (harmonic for acute cholecystitis): a randomized, double-blind, controlled trial comparing the use of harmonic scalpel to monopolar diathermy for laparoscopic cholecystectomy in cases of acute cholecystitis.

ABSTRACT

BACKGROUND: The HARMONIC SCALPEL (H) is an advanced ultrasonic cutting and coagulating surgical device with important clinical advantages, such as reduced ligature demand; greater precision due to minimal lateral thermal tissue damage; minimal smoke production; absence of electric corrents running through the patient. However, there are no prospective RCTs demonstrating the advantages of H compared to the conventional monopolar diathermy (MD) during laparoscopic cholecystectomy (LC) in cases of acute cholecystitis (AC). METHODS: This study was a prospective, single-center, randomized trial (Trial Registration Number NCT00746850) designed to investigate whether the use of H can reduce the incidence of intra-operative conversion during LC in cases of AC, compared to the use of MD. Patients were divided into two groups both groups underwent early LC, within 72 hours of diagnosis, using H and MD respectively (H = experimental/study group, MD = control group). The study was designed and conducted in accordance with the regulations of Good Clinical Practice. RESULTS: 42 patients were randomly assigned the use of H (21 patients) or MD (21 patients) during LC. The two groups were comparable in terms of basic patient characteristics. Mean operating time in the H group was 101.3 minutes compared to 106.4 minutes in the control group (p=ns); overall blood loss was significantly lower in the H group. Conversion rate was 4.7% for the H group, which was significantly lower than the 33% conversion rate for the control group (p<0.05). Post-operative morbidity rates differed slightly 19% and 23% in the H and control groups, respectively (p=ns). Average post-operative hospitalization lasted 5.2 days in the H group compared to 5.4 days in the control group (p=ns). CONCLUSIONS: The use of H appears to correlate with reduced rates of laparoscopic-open conversion. Given this evidence, H may be more suitable than MD for technically demanding cases of AC.