JAMA Otolaryn Head Neck Cancer

How pre/post-op care differs for cannabis users

August 27, 2024

Cannabis users may warrant special attention regarding pre-op counseling; intra-op anesthesia including drug-drug interactions; and post-op management of pain, nausea, and vomiting.

• Pre-op. Acutely intoxicated patients may not be capable of signing informed consent. Most executive functions are restored around 5 hours after inhalational use; however, more time may be required after oral ingestion. Although evidence is limited, a reasonable ask is abstinence from cannabis starting midnight before a surgery, as this timing minimizes cannabis withdrawal syndrome. Gradual tapering over time could be considered for heavy users; however, rapid tapering could lead to cannabis withdrawal syndrome, which may last for weeks.
• Intra-op. Cannabis use has been linked to increased rates of myocardial ischemia, higher tolerance to standard anesthesia dosing, and prolonged sedation. Cannabis interacts with numerous medications, notably common anticoagulants. As a potent CYP-enzyme inhibitor, it has clinically significant interactions with many drugs used in anesthesia. THC has been linked with increased sedation in combination with other CNS agents, e.g., opioids and benzodiazepines. CBD is a potent inhibitor of enzymes involved in the metabolism of propofol, morphine, and lorazepam. Patients with short-term intoxication may require less propofol for induction; those with long-term use may require more.
• Post-op. Though studies are mixed, cannabis use may be linked to increased post-op pain (and in some cases, increased opioid needs), sedation, and prolonged ventilatory support. While some people employ cannabis for nausea, studies are mixed on whether cannabis use increases post-op nausea. Cannabis hyperemesis syndrome, a form of cyclic vomiting, may occur in heavy, long-term users. Around 21% of those who use cannabis qualify as having cannabis use disorder; these patients are at higher risk of hyperalgesia and postoperative nausea/vomiting.

Source:

Mims MM, et al. (2024, August 22). JAMA Otolaryngol Head Neck Surg. Surgery-Related Considerations in Treating People Who Use Cannabis: A Review. https://pubmed.ncbi.nlm.nih.gov/39172477