Review of Practices Reported for Preoperative Food and Water Restriction of Laboratory Pigs (Sus scrofa)

The traditionally cited recommendations for the preoperative restriction of food (including bedding) and water in pigs do not appear to be evidence-based. As a preliminary step in elucidating a rationale for and standardizing preoperative food and water restriction (PFWR), this structured review recorded recent reported practices in PFWR in laboratory pigs and its consequences. Medline, Google Scholar and Web of Science databases were searched for recently published (2012 - 2014) recovery surgery procedures in pigs. Information pertaining to PFWR practices, as delineated in the ARRIVE guidelines, was extracted from the 233 articles retrieved. Food withdrawal was described in 73 of the 233 (31%) papers evaluated, bedding withdrawal in 5 articles (2%), and water withholding in 13 publications (6%) papers. Food, bedding, and water withdrawal regimens had a median (range) duration of 12 (4 to 48), 48 (48 to 72), and 12 (2 to 12) h, respectively. Compared with other types of procedures, articles describing gastrointestinal or abdominal surgery were more likely to report fasting regimes. Liquid diets were described in 11 of the 233 (5%) publications evaluated. Adverse effects of PFWR effects were not reported. These data reveal considerable variation in PFWR practices. The stress of fasting coupled with the absence of evidence for current recommendations makes the rationale and standards for PFWR in pigs worthy of further study.