Established practice
Practice guidelines for pre-op fasting issued by the American Society
of Anesthesiologists in 1999 said it was appropriate for patients to
drink clear liquids at least 2 hours before elective procedures. The
ASA reiterated that recommendation in its latest guideline update
issued in 2011.
"The guidelines were never intended to drive a change in practice
habits or do away with NPO altogether," says anesthesiologist Joyce
Wahr, MD, director of the University of Minnesota Health
Preoperative Assessment Center. "They're intended to inform about
when it's safe to anesthetize patients without having them aspirate."
But fear of pulmonary aspiration remains a significant barrier to
providers letting patients drink clear liquids before surgery, says TJ
Gan, MD, MHS, FRCA, professor and chairman of the department of
anesthesiology at Stony Brook (N.Y.) School of Medicine.
"A major concern is that oral intake before surgery will increase
residual gastric volume and a decrease in gastric pH, causing a higher
risk of aspiration," he says.
Dr. Gan has some advice for hesitant providers: Don't worry about
it. Seriously. He says studies have shown that ingestion of clear liquids
2 hours before surgery results in smaller residual gastric volumes and
higher gastric pH levels compared with longer fasts. In addition, the
rate of gastric emptying in obese individuals is the same as it is in
people of average weight, he says.
"There is absolutely no risk in letting patients drink clear fluid up
until 2 hours before surgery," he adds. "If fact, it promotes gastric
emptying. It's actually safer."
Saying no to NPO has been slow to catch on because health care is
stuck in emphasizing what providers need to accomplish instead of
O C T O B E R 2 0 1 8 • O U T PA T I E N T S U R G E R Y. N E T • 5 3
