Study: Standard preoperative fasting instructions sufficient for diabetic patients

Editor's Note

Recent research suggests that minimizing the risk of perioperative pulmonary aspiration in diabetic patients does not require different fasting instructions. However, at least one expert has questioned the results, and widespread glucagon-like peptide-1 (GLP-1) receptor agonists for the treatment of both type 2 diabetes and weight loss can complicate the issue, according to a May 6 report on the study in Medscape Medical News.

Published in the April 2024 issue of Anesthesiology, the prospective study focused on 180 patients, 84 with diabetes and 96 without, undergoing elective surgery and following standard preoperative fasting guidelines. Gastric ultrasound showed no significant difference between the two groups. The frequency of full stomach was also similar. As a result, the researchers concluded that current fasting guidelines by the American Society of Anesthesiologists are similarly effective in diabetic and nondiabetic patients.

Mark A. Warner, MD, professor of anesthesiology at the Mayo Clinic in Rochester, Minnesota, wrote in an accompanying editorial that the findings ‘will be very helpful to anesthesiologists,’ although he noted that the exclusion of people with a BMI > 40 is a limitation, Medscape reports. He also noted that the use of GLP-1 receptor agonists will likely change perioperative fasting guidelines. “The inconsistent impact of GLP-1 agonists on gastric emptying, ranging from little to significant, makes it difficult for anesthesiologists to gauge whether or not patients taking GLP-1 agonists are likely to have preoperative gastric liquid or solid contents that could cause subsequent damage if regurgitated,” he wrote.

The Medscape report also includes testimony from an endocrinologist who disputes the results based on patient health. "They've picked the wrong group of diabetics," said Michael Horowitz, MBBS, PhD, FRACP, director of the Endocrine and Metabolic Unit at the Royal Adelaide Hospital and professor of medicine at Adelaide Medical School in Adelaide, Australia, citing the average patient A1c of 7.2%, and the fact that fewer than half of patients had microvascular or neuropathic complications. "This is not a group where you would expect a very high prevalence of delayed emptying."