Timing of early laparoscopic cholecystectomy for acute calculous cholecystitis revised: Protocol of a systematic review and meta-analysis of results.

Background: Early laparoscopic cholecystectomy has been adopted as the treatment of choice for acute cholecystitis due to a shorter hospital length of stay and no increased morbidity when compared to delayed cholecystectomy. However, randomised studies and meta-analysis report a wide array of timings of early cholecystectomy, most of them set at 72 h following admission. Setting early cholecystectomy at 72 h or even later may influence analysis due to a shift towards a more balanced comparison. At this time, the rate of resolving acute cholecystitis and the rate of ongoing acute process because of failed conservative treatment could be not so different when compared to those operated with a delayed timing of 6-12 weeks. As a result, randomised comparison with such timing for early cholecystectomy and meta-analysis including such studies may have missed a possible advantage of an early cholecystectomy performed within 24 h of the admission, when conservative treatment failure has less potential effects on morbidity. This review will explore pooled data focused on randomised studies with a set timing of early cholecystectomy as a maximum of 24 h following admission, with the aim of verifying the hypothesis that cholecystectomy within 24 h may report a lower post-operative complication rate compared to a delayed intervention. Methods: A systematic review of the literature will identify randomised clinical studies that compared early and delayed cholecystectomy. Pooled data from studies that settled the early intervention within 24 h from admission will be explored and compared in a sub-group analysis with pooled data of studies that settled early intervention as more than 24 h. Discussion: This paper will not provide evidence strong enough to change the clinical practice, but in case the hypothesis is verified, it will invite to re-consider the timing of early cholecystectomy and might promote future clinical research focusing on an accurate definition of timing for early cholecystectomy for acute cholecystitis.