Research

Energy balance

Preoperative carbohydrate loading with iso-osmolar drinks 2-3 hours before anesthesia reduces postoperative insulin resistance and length of stay in major abdominal surgery, and is safe in bariatric patients.

Follow your anesthesia team's instructions on preoperative fasting. Modern ERAS protocols often allow you to drink a special carbohydrate-rich clear fluid up to 2 hours before your surgery. This helps reduce stress on your body and may shorten your hospital stay. Do not eat solid food within 6 hours of surgery.

ModerateSupportsMEDIUM confidence
Preoperative carbohydrate conditioning, using iso-osmolar drinks ingested 2–3 h before induction of anaesthesia, attenuated development of postoperative insulin resistance, reduced postoperative nitrogen and protein losses and maintained lean body mass... preoperative carbohydrate ingestion did not lead to an increase in aspiration-related complications in patients undergoing laparoscopic gastric bypass
Anders Thorell et al. · World Journal of Surgery · 2016

Why this rating

Based on meta-analyses in major abdominal surgery and specific studies in bariatric patients, but compliance was low in one RCT.

Source

Guidelines for Perioperative Care in Bariatric Surgery: Enhanced Recovery After Surgery (ERAS) Society Recommendations

Anders Thorell et al. · World Journal of Surgery · 2016

DOI 10.1007/s00268-016-3492-3

clinical_guidelineCited 609×
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DOI resolved against Crossref · corpus check 2026-06-10

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