Continuous Gas Outflow Is More Effective Than Carbon Filters to Evacuate Smoke in Laparoscopic Colorectal Resections: A Comparative Study

Abstract

Background: Carbon filters and expensive evacuation machines are available to evacuate surgical smoke in long-lasting laparoscopic operations and achieve good visibility and patient’s safety. Methods: This study was aimed to determine which of two methods for laparoscopic smoke evacuation is most effective getting the best visibility. 20 patients submitted to elective laparoscopic colorectal resections were allocated to be operated using, either a carbon filter (Group A) or a home-made tubing with a continuous suction (Group B) connected through one of the ports to the hospital vacuum system: both methods were regulated with a roller clamp to increase smoke evacuation in order to obtain good visibility. A mono-polar hook and the LigasureV 5-mm vessel-sealing device were used. Groups were comparable for demographic characteristics, surgical techniques, and malignancy. Mann-Whitney and Fisher’s exact test were used for statistics. Results: Morbidity was 10%. There was no mortality, and there was no difference between Group A and B according to complications ( p = 1.00), hospital stay ( p = 0.23), duration of the operation ( p = 0.79) and total consumption of CO 2 ( p = 0.36). However, the number of times that the clamp had to be released (Group A: 3.4 + 1 vs Group B: 1.5 + 1) ( p = 0.006) and that a port had to be opened freely to quickly evacuate dense smoke (Group A: 0.9 + 0.7 vs Group B: 0) ( p = 0.002) was very significantly increased in Group A as compared to Group B. Mean follow-up was 60 months and no port site metastases that could be a consequence of “chimney effect” or wound recurrence have been detected. Conclusions: The surgeon’s subjective impression that carbon filters are less effective for smoke evacuation than continuous outflow of gas through a port connected to the hospital vacuum source was confirmed. This simple method is advised for long-lasting laparoscopic procedures to improve visibility throughout the procedure.