An article written by CNN describes a study conducted by the Journal of the American Osteopathic Association that followed 250 patients receiving minimally invasive surgery in Colorado, where recreational marijuana has been legalized. The study found that patients using marijuana regularly, for recreational or medical purposes, required larger doses of anesthesia for their procedures. Specifically, cannabis users needed 220 percent more propofol, 14 percent more fentanyl and 20 percent more midazolam.
EHC NOTE: This study has a relatively low number of study participants, and was retrospective, limitations which may decrease the wide application of the findings. Researchers looked at medical records and compared the amount of sedation for each patient, they did not control other variables. Despite these factors, 13.5% of adults use cannabis in the United States, and use has increased by 43% between 2007 and 2015. With such a significant increase in use, anesthesiologists and other perioperative providers should be aware and plan accordingly for the possible impact on anesthetic agent requirements when caring for patients who regularly use cannabis.