A variety of studies have looked at how the body recovers after stopping smoking.

In six months the lungs have a restored ability to fight infection and the risk of postoperative breathing problems is significantly less. Even six to eight weeks without cigarettes can improve lung function and decrease wound infections and heart problems. Wound healing improves after three weeks smoke-free.

Fortunately, some of the benefits of stopping smoking come more quickly. In just four hours the level of carbon monoxide in the blood is halved. Eight hours without smoking reduces the level of carbon monoxide and nicotine in the blood to safe levels.

Many studies have found that smokers who stop smoking for a few weeks before surgery do much better than those who continue to smoke, but not as well as people who have never smoked. In one study, the risk of the a surgical flap dying was halved if patients stopped smoking before surgery, but was still four times the risk of patients who had never smoked (Padubidri 2001).

In one famous study, smokers who needed joint replacement surgery were randomly divided into two groups. The “Control” group got normal treatment, while the “Intervention” group got normal treatment plus six weeks of smoking cessation counselling and nicotine replacement therapy. Even though some of the patients in the control group stopped smoking, and 40% of the Intervention group were not able to quit, the result was dramatic:

The complication rate was 52% in the Control group and only 18% in the Intervention group.

There was also a reduction in wound problems from 31% in the control group to 5% in the intervention group. On average, the intervention group stayed in hospital for two fewer days than the controlgroup, and 94% of the patient days in the intensive careunit were attributable to the control group. (Moller 2002).

Stopping smoking before surgery makes an enormous difference to your chances of having an uneventful anesthetic and a successful surgery.
If it results in you stopping smoking for good, you will have done the best thing possible for your future health.