Regular cannabis users face an elevated risk of complications prior to, during, and following surgical procedures.
Additionally, smoking within two hours prior to surgery increases the likelihood of experiencing a heightened risk of a cardiac event resulting from the surgical procedure.
This is according to researchers with the University of Texas Health Science Centre in Houston, whose study is published in JAMA Surgery.
Their findings support the need to include screening for cannabis use disorder in any pre-operative risk assessment.
The study found that cannabis use disorder was associated with a modest increased risk of perioperative morbidity and mortality after major elective, inpatient, non-cardiac surgery.
Researchers analysed 12,422 patients after major elective, non-cardiac surgery.
They say that after major surgery, people with cannabis use disorder (CUD) have a higher chance of experiencing:
Stroke
Blood clots
Kidney problems
Respiratory failure
Death.
The risk of complications for CUD patients is 7.73% compared to 6.57% for non-CUD patients – a significant difference, the authors claim.
The pharmacologic effects of cannabinoids may contribute to an increased risk of perioperative complications, including:
Bronchial hyperreactivity
Cannabis withdrawal syndrome
Immunosuppression
Interaction with perioperative medications.
Additionally, three in 10 users develop a clinically significant CUD and face higher hospital bills than people without the disorder.
New guidelines regarding cannabis use by patients were published at the beginning of the year by the American Society of Regional Anaesthesia and Pain Medicine.
They advise that patients undergoing a procedure that requires anaesthesia should disclose their cannabis use before surgery.
The guidelines also noted that regular use of marijuana may worsen pain and nausea after surgery, increasing the need for powerful but addictive opioid painkillers.
They also suggested that healthcare professionals should counsel patients who use cannabis about the possible risks and effects of their habit.
At the time, senior author of the guidelines Samer Narouze, who is also a Professor of Surgery and Anaesthesiology at Northeast Ohio Medical University and president of the Society, said that he hoped the guidelines would ‘serve as a roadmap to help better care for patients who use cannabis and need surgery’.
He added: ‘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.’
The National Centre for Drug Abuse Statistics reveals that 55 million American adults use marijuana.
Meanwhile, 14 million people have used cannabis in the UK, making it the most popular illicit drug according to figures from the UK Addiction Treatment Centres website.
Marijuana use by patients is a common challenge for healthcare professionals across all sectors.
Last year, a survey by the American Dental Association (ADA) revealed that 52% of dentists in the US said patients had arrived to appointments high on marijuana or another drug, with 46% saying they had to increase anaesthesia because of the way the combination of the two can impact the central nervous system.
