I feel you should consider quitting this habit before the surgery because of two main reasons. One, there is some amount of tobacco in your joint which, as is well known, hampers good lung functioning and impairs cardiovascular status. Secondly, smoking
cannabis also has been shown to be associated with sudden deaths due to stroke
. So in my opinion, any surgical procedure involving general anaesthesia
would be less risky in people who do not smoke at all. But you also need to consider that having taken this for so long, you may suffer from withdrawal symptoms
when you quit.
Hope this has been of help. Best wishes for your surgery.