Cannabis use may worsen pain and nausea after a procedure and increase the need to prescribe opioids for pain, an anesthesia and pain medicine group says.
Patients getting procedures that require anesthesia should be asked about cannabis use, according to new guidelines from the American Society of Regional Anesthesia and Pain Medicine (ASRA Pain Medicine).
Cannabis use has increased over the past 20 years. Cannabis is second only to alcohol in the use of psychotropic substances, with about 10% of Americans using cannabis monthly, according to the U.S. Substance Abuse and Mental Health Services Administration.
The new guidelines were published by the journal Regional Anesthesia & Pain Medicine. "Surgical patients using cannabinoids are at potential increased risk for negative perioperative outcomes," the guidelines say. For patients undergoing surgery, cannabis use may worsen pain and nausea after a procedure and increase the need to prescribe opioids for pain management, according to a prepared statement from ASRA Pain Medicine.
"Before surgery, anesthesiologists should ask patients if they use cannabis—whether medicinally or recreationally—and be prepared to possibly change the anesthesia plan or delay the procedure in certain situations," Samer Narouze, MD, PhD, senior author of the guidelines and ASRA Pain Medicine president, said in the prepared statement. "They also need to counsel patients about the possible risks and effects of cannabis. For example, even though some people use cannabis therapeutically to help relieve pain, studies have shown regular users may have more pain and nausea after surgery, not less, and may need more medications, including opioids, to manage the discomfort. We hope the guidelines will serve as roadmap to help better care for patients who use cannabis and need surgery."
The guidelines were crafted by ASRA Pain Medicine's Perioperative Use of Cannabis and Cannabinoids Guidelines Committee. The panel featured 13 experts, including anesthesiologists, chronic pain physicians and a patient advocate.
The panel fielded nine questions and made 21 recommendations. The recommendations were graded on a scale established by the United States Preventive Services Task Force (USPSTF). The USPSTF assigns letter grades to recommendations: A, B, C, D, and I. An A grade is given to recommendations with the highest level of evidence. An I grade is given to recommendations with insufficient evidence.
The panel assigned an A grade to four recommendations:
- Screen all patients for cannabis use before surgery
- Postpone elective surgery for patients who have an altered mental status or impaired decision-making ability at the time of surgery
- Counsel heavy users about the potentially negative effects of cannabis use on postoperative pain control
- Counsel pregnant patients on the risks of cannabis use to the unborn child
The panel assigned a B grade to two recommendations:
- Counsel patients about the potential risks of cannabinoid use before, during, and after surgery
- Discourage cannabis use during pregnancy and immediately following childbirth
"The medical, social, and political landscape of cannabis is fluid, changing on an almost daily basis. Cannabinoid use in the perioperative setting has significant potential negative medical implications," the guidelines say.
Christopher Cheney is the senior clinical care editor at HealthLeaders.
Cannabis is second only to alcohol in the use of psychotropic substances among Americans.
New guidelines call on healthcare providers to screen all patients for cannabis use before surgery.
The guidelines say elective surgery should be postponed for patients who have an altered mental status or impaired decision-making ability at the time of surgery.