Preoperative fasting could become a thing of the past.
New research challenges the long-standing practice of requiring patients to fast before surgery to mitigate the risk of post-surgical vomiting.
An analysis of published data indicates no significant evidence supporting the efficacy of preoperative fasting in preventing aspiration during anaesthesia.
Patients universally express discomfort regarding fasting before procedures, primarily aimed at avoiding the risk of vomiting.
However, the latest findings reveal no correlation between fasting and reduced post-operative vomiting rates.
This latest study involved a systematic review of randomised clinical trials and observational studies published between 1 January 2016 and 1 December 2023, focusing on aspiration events.
A total of 801 patients were in the experimental group and 990 in the control group. The primary outcome assessed was clinical aspiration, with secondary outcomes including gastric volume and pH levels.
From an initial search yielding 3580 references, 17 studies were included in the final analysis. Of these, nine specifically reported on aspiration outcomes.
The results demonstrated that clinical aspiration rates were unaffected by the fasting regimens: aspiration occurred in only four of 801 patients (0.50%) in the experimental group compared to seven of 990 (0.71%) in the control group.
Trial sequential analysis indicated a low likelihood of identifying a significant impact of fasting on aspiration risk.
Dr Edward Livingston, health sciences professor of surgery at the David Geffen School of Medicine at UCLA and the study’s senior author, said: ‘Fasting for long periods of time is extremely uncomfortable and patients really don’t like to do it. Our research suggests that long periods of fasting may not be necessary.’
The researchers have initiated further exploration into the correlation between fasting guidelines and actual fasting durations in various healthcare settings, examining over 80 published papers.
This analysis revealed that patients often fast for significantly longer than necessary, resulting in considerable discomfort.
Moving forward, prospective trials are planned to investigate reduced fasting durations before surgery, utilising modern assessment methods such as preoperative gastric ultrasound to evaluate the safety of proceeding with anaesthesia.
The findings will be published in the August 2025 issue of the peer-reviewed journal Surgery.
