Smoking marijuana prior to surgery? Here’s why your doctor needs to know

Discussing your favorite strain of weed might seem like a strange topic to discuss with your doctor before going under the knife, so to speak. But some of Colorado’s surgeons, nurses and anesthesiologists say it’s imperative.

Disclosing smoking habits could help them determine how much of a sedative is needed prior to surgery.

In a report originally released on NBC, observations and initial research revealed that a cannabis user’s history of using the substance could help or hinder their symptoms in the recovery room. Following legalization in the state of Colorado, patients are more willing than usual to talk to their doctors about their consumption habits.

“It has been destigmatized here in Colorado,” Dr. Andrew Monte, an associate professor of emergency medicine and medical toxicology at the University of Colorado School of Medicine and UCHealth, told CNN. “We’re ahead of the game in terms of our ability to talk to patients about it. We’re also ahead of the game in identifying complications associated with use.”

But patients still might not be aware of some of the risks involved. A small study published in May showed that marijuana users required more than triple the amount of one common sedation medicine, propofol, than nonusers. Another study published last year in the journal Patient Safety in Surgery showed marijuana users reported feeling greater pain, and consumed more opioids in the hospital after vehicle crash injuries compared with nonusers.

More research is needed, yet, these findings have brought new questions to light. Dr. Mark Twardowski, the more recent study’s author, had a few:

If pot users indeed need more anesthesia, are there increased risks for breathing problems during minor procedures? Are there higher costs with the use of more medication, if a second or third bottle of anesthesia must be routinely opened? And what does regular cannabis use mean for recovery post-surgery?

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Unfortunately, it could take years for experts to undergo such research, as marijuana is still illegal on the federal level. New policies would need to be implemented as well. Dr. Joy Hawkins, a professor of anesthesiology at the University of Colorado School of Medicine and president of the Colorado Society of Anesthesiologists, says The Colorado Hospital Association currently doesn’t track anesthesia needs or costs specific to marijuana users.

But they might need to. Hawkins told CNN that anesthesiologists have noticed that patients who use marijuana appear to have built up a tolerance to some common anesthesia drugs, which “help people fall asleep during general anesthesia or stay relaxed during conscious ‘twilight’ sedation.” But he also noted that higher doses can increase “potentially serious side effects” such as low blood pressure and heart function.

“Since they do not receive marijuana while in the hospital, they require a higher replacement dose of opioids,” said Dr. David Bar-Or, who directs trauma research at Swedish Medical Center in Englewood, Colo., and several other hospitals in Colorado, Texas, Missouri and Kansas.

Hawkins also pointed out that limited airway flow could be an issue during surgery for smokers, as weed “acts very much like cigarettes,” thus irritating the airway.

It may be a challenge for some patients to divulge information about marijuana use — especially in emergency scenarios — but it can be just as difficult for doctors to adjust the amount of medication being administered.

“For marijuana, it’s a bit of the Wild West,” Hawkins said. “We just don’t know what’s in these products that they’re using.”

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In contrast, doctors are also observing how marijuana can have a positive impact following surgery. Increasingly, patients are turning to cannabis as an alternative to opioids or other painkillers.

“I didn’t experience the pain I thought I would,” Denver resident Matthew Sheahan told CNN. He used marijuana to relieve postoperative pain after his wisdom teeth were removed four years ago. He lived in Ohio at the time, and didn’t tell his doctor about his secret pain reliever for fear of legal implications.

Hawkins says her cohorts are hopeful that more studies will be published in the coming years as more states nationwide legalize marijuana.

“We’re all wishing we had a little more data to rely on,” Hawkins said.

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