Marijuana Use Should be Disclosed Before Surgery, New Guidelines Say

Before undergoing surgery, patients should tell their anesthesiologist if they're a heavy cannabis user and, according to new guidelines, anesthesiologists should be asking about use.

Cannabis use, particularly when it's regular and heavy, can leave patients in more pain than normal after surgery, and getting high just before an operation can put a patient at risk for heart problems, even a heart attack, said Dr. Samer Narouze, president of the American Society of Regional Anesthesia and Pain Medicine.

The society released the guidelines Jan. 3, and they are intended to be both educational and instructive, Narouze said. While medical schools are now starting to teach about cannabis, most practicing doctors learned little about the drug or the body's reaction to it during their training.

"It's a problem for every practicing anesthesiologist. They have this patient and they just don't know what to do," said Narouze, also chairman of the Center for Pain Medicine at Western Reserve Hospital in Cuyahoga Falls, Ohio.

The guidelines recommend anesthesiologists ask patients whether they use cannabis, how much, how often, how recently, what type of marijuana and whether it was smoked or ingested. The guidelines also call for postponing elective surgery if a patient arrives high and educating pregnant patients about the risks of using marijuana on their baby.

Some heavy marijuana users may require more anesthesia to fall asleep or keep them asleep, he said. Heavy use may leave patients more agitated during recovery, and someone acutely intoxicated with cannabis may feel confused, have a racing heart and panic episodes, and cannot appropriately consent to surgery, Narouze said.

A simple conversation before the operation can help the anesthesiologist provide appropriate pain control and help the patient understand their risks, Narouze said. A heavy user might need more monitoring during recovery and their discharge could be delayed.

"If the anesthesiologist is aware of the risks," he said, "they can put the pieces together and manage the patient well."