Marijuana affects many parts of the body. These effects can impact your surgery through the following ways:
- Respiration: Marijuana affects the airways making it harder to place a breathing tube for anesthesia. Marijuana also affects the lungs and can cause wheezing, coughing, and chronic bronchitis.
- Cardiac effects: Marijuana affects heart rate and blood pressure and has the potential to increase risks of a heart attack and/or stroke.
- Pain management: Marijuana may interfere with pain control and the amount of pain medication needed to provide relief following an operation.
You should discuss with your surgical team if you are using any form of marijuana or cannabis products. It can affect the outcome of your surgery. It is recommended to stop using marijuana products 72 hours before surgery.
Their full statement goes into greater detail. https://www.facs.org/for-patients/safe-pain-management/marijuana-and-surgery/
Also see What They Don’t Tell You About Cannabis Before Surgery