3.15 Smoking and complications in medical treatment

3.15.1 Smoking and surgical outcomes

Smoking causes a range of adverse surgical outcomes, particularly related to respiratory complications in the peri-operative and post-operative period, as well as suboptimal wound healing and increased risk of infection.5

Smoking affects heart rate, blood flow, tissue oxygenation, airways clearance and the immune system, each of which impact upon the body's ability to withstand surgical procedures and anaesthesia, and to optimise the healing process.82 A recent review has found that even short-term smoking cessation prior to surgery may help reduce the risk of post-operative complications.83 Smokers are also more likely to require higher levels of analgesia (painkillers) peri-operatively than non-smokers.82

The Australian and New Zealand College of Anaesthetists has stated that smoking is an identifiable major risk factor relating to surgery and the peri-operative period, and recommends that patients who smoke be encouraged to stop smoking at least six to eight weeks before surgery. In the short term, smoking should not be permitted in the 12 hours before surgery.82

3.15.2 Interaction of smoking with drugs and other medical therapies

Nicotine interacts with a range of drugs, with important implications for drug therapy. Drugs may be processed by the body in a different way when nicotine is present, and nicotine may also mediate the effectiveness of certain drugs. Drug types known to be affected by co-use of nicotine include oral contraceptives, sedatives, and drugs used to treat a number of different conditions, including aspects of heart disease, mental health problems, and breathing difficulties. These interactions are capable of causing clinically significant outcomes, making it vital that health professionals are aware of a patient's smoking status.12, 84

There is also evidence that the effectiveness of radiotherapy and chemotherapy (both used in the treatment of cancer) are affected by tobacco smoking.85, 86 For example, a study investigating patients with cancers of the head and neck who underwent radiotherapy while continuing to smoke showed that they had a reduced response to the treatment, and poorer two year survival rates.87 Chemotherapy patients who smoke may also experience more severe side effects, increased impairment of immune function, and reduced effectiveness of treatment than non-smoking patients.85 Therefore the cancer patient who also smokes faces a greater risk of complications and poorer outcomes from surgical, radiotherapy and chemotherapy treatments.86