A risk-benefit analysis of alternating low-pressure CO2 insufflation and fluid medium in arthroscopic knee ACL reconstruction.

Abstract

The purpose of this study was to test the hypothesis that the surgical technique using alternating fluid irrigation and carbon dioxide (CO2) gas medium as a means of knee joint distension during arthroscopy is a safe and effective method, compared to traditional fluid arthroscopy. This prospective randomized comparative study involved 94 patients undergoing the same arthroscopic ACL reconstruction surgical procedure except for the medium used to distend the joint: In a first group of 48 patients ("ACL gas" group), CO2 insufflation was mainly used, at a low pressure of 40-50 mmHg, alternating with a fluid medium for knee joint washout only. In the second group of 46 patients, classical arthroscopic joint distension by fluid was used, with a pump pressure of 50-70 mmHg. Early pre- and post-operative complications, duration of surgery, intraoperative monitoring data and particularly the end-tidal carbon dioxide (EtCO2) as a marker of CO2 blood diffusion were prospectively collected. EtCO2 and other monitoring data changes before and after tourniquet release were not different between the two groups. Tourniquet time was significantly longer when using fluid rather than gas. We observed 3 cases of small and localized subcutaneous emphysema, resolving completely within hours. Hematoma and reflex sympathetic dystrophy occurred more often in the "ACL fluid" group, with no statistical significance. Low-pressure CO2 knee joint insufflation proved to be a safe technique capable of improving surgical comfort compared with the use of fluid alone. The CO2 blood diffusion measured by end-tidal carbon dioxide monitoring during ACL arthroscopic reconstruction was similar with or without gas insufflation.