Patients should discuss their cannabis use with their medical team before any surgical procedure. Disclosing this information allows healthcare professionals to make informed decisions and adjust care plans. Abstaining from cannabis before surgery is advised to minimize complications and promote a safer surgical experience.
Impact on Anesthesia
Cannabis, especially its active component tetrahydrocannabinol (THC), can significantly alter how a patient responds to anesthesia. Individuals who use cannabis may require a higher dose of anesthetic agents to achieve and maintain sedation during surgery. Cannabis users might need up to 50% more anesthesia. This altered requirement can lead to risks such as insufficient sedation during the procedure or a prolonged recovery from anesthesia.
Cannabis use can lead to cardiovascular instability during anesthesia. THC increases heart rate and blood pressure, which can be particularly hazardous for patients with existing heart conditions. This effect can elevate the risk of adverse cardiac events, including myocardial ischemia or irregular heart rhythms. Interactions between cannabis and anesthetic drugs can also make a patient’s response to sedation less predictable.
Effects on Body Systems
Smoking cannabis can have notable effects on the respiratory system, creating challenges during surgery. It can irritate the airways, leading to inflammation, increased mucus production, wheezing, and symptoms similar to chronic bronchitis. These respiratory issues can complicate placing a breathing tube for anesthesia and raise the risk of post-operative breathing difficulties, such as bronchospasm or pneumonia. Swelling of the uvula has also been observed in cannabis smokers, which can further obstruct the airway.
Beyond its direct interaction with anesthesia, cannabis can influence the cardiovascular system by causing fluctuations in heart rate and blood pressure. Users may experience an immediate increase in heart rate and blood pressure, sometimes followed by a drop. Such instability can pose a challenge during surgery, especially for those with underlying heart conditions. Cannabis use can also affect the gastrointestinal system, potentially delaying the emptying of stomach contents. This delayed emptying increases the risk of aspiration, where stomach contents enter the lungs during anesthesia.
Post-Operative Recovery
Cannabis use can complicate pain management during the post-operative period. Patients who use cannabis often report higher levels of pain after surgery and may require larger doses of pain medications, including opioids, to achieve adequate relief. This increased need for medication can lead to a higher incidence of side effects, such as constipation. The perceived pain-relieving benefits of cannabis for chronic conditions do not reliably extend to acute post-surgical pain.
The healing process following surgery can be impacted by cannabis use. Some evidence suggests that cannabis may delay wound healing, prolonging recovery. While some animal studies hint at potential benefits, human research on this topic remains limited and shows conflicting results. Cannabis use has also been linked to an increased risk of post-operative nausea and vomiting. Regular cannabis users may experience withdrawal symptoms after surgery, which can complicate their recovery.
Recommendations for Patients
Provide your surgical team with complete and honest information about any cannabis use, including how often you use it, the method of consumption (such as smoking, edibles, or vaping), and the type of product. Medical professionals rely on this detailed disclosure to create a safe anesthesia plan and to anticipate and manage any potential complications. Healthcare providers are focused on ensuring patient safety and do not approach this information with judgment. Withholding details about cannabis use can compromise the safety and success of your surgical outcome.
The recommended period of abstinence from cannabis before surgery can vary, but discontinuing use several weeks prior is advisable. While some guidelines suggest a minimum of 72 hours before general anesthesia, longer periods, such as 10 days or even four weeks for heavy users or those consuming edibles, are often recommended, particularly due to lingering respiratory effects from inhaled forms. A direct conversation with your surgical team is important to determine the specific abstinence period appropriate for your individual health and the planned procedure.