Q & A: Cannabis, Surgery and Anesthesia

Answer: When looking for evidence-based and specific guidance related to cannabis-using patients preparing for scheduled surgery, we find limited results. However, a few reviews, expert opinions, position papers and posts may offer meaningful and relevant insights.

In one early review published in the Journal of the American Association of Nurse Anesthetists (S. Dickerson, RN., 1980), the author suggests that anesthesia should be avoided, if at all possible, in any patient with cannabis use within the past 72 hours.”¹ That opinion has been adopted by another more recent review (2018)² and a position paper published on the American College of Surgeons website.³ 

However, more recent information written by an expert panel of anesthesiologists, chronic pain physicians, as well as patient advocates published on the website of the American Society of Anesthesiologists (D. Dickerson M.D., 2023)⁴ advises that:

• Smoking weed can significantly increase heart rate and blood pressure within the first two hours following use and may increase the patient’s risk of suffering a surgery-related heart attack. 
• Same-day smoking of marijuana outside the two-hour window may still carry some risk, although the evidence is not as strong as for use within two hours. 
• Smoking weed the day before surgery might have a negative impact, especially for someone who smokes it frequently. You may be advised to stop smoking marijuana one or more days before surgery unless you use it for a medical reason. 

They further advise you to tell your anesthesiologist if you were hoping to use cannabis to get a good night’s sleep, reduce anxiety, or relax before surgery. They can use their medical expertise to suggest other options that will not increase your risk.   

Additionally, there is one trial (I. Ngozi et al., 2021) that I find informative and related to helping answer some aspects of your concern and question. Daily, weekly, and monthly cannabis users needed increasingly higher dosages of the anesthetic propofol, respectively, than non-users to achieve effective analgesia.⁵ 

Endnotes:

1. Dickerson SJ. Cannabis and its effect on anesthesia. AANA J. 1980 Dec;48(6):526-8. 
2. Huson HB, Granados TM, Rasko Y. Surgical considerations of marijuana use in elective procedures. Heliyon. 2018 Sep 15;4(9):e00779.  
3. American College of Surgeons. For Patients, Marijuana and Surgery. 
4. Shah S, Schwenk ES, Sondekoppam RV, Clarke H, Zakowski M, Rzasa-Lynn RS, Yeung B, Nicholson K, Schwartz G, Hooten WM, Wallace M, Viscusi ER, Narouze S. ASRA Pain Medicine consensus guidelines on the management of the perioperative patient on cannabis and cannabinoids. Reg Anesth Pain Med. 2023 Mar;48(3):97-117.
5. Imasogie N, Rose RV, Wilson A. High quantities: Evaluating the association between cannabis use and propofol anesthesia during endoscopy. PLoS One. 2021 Mar 4;16(3):e0248062.