Smoking is a risk factor for complications during and after surgery. However, if you stop smoking in the weeks or months preceding surgery, you may be able to reduce your risk of complications. A study recently published in The Lancet suggests that smokers who begin a smoking cessation program six to eight weeks prior to hip or knee replacement surgery may significantly reduce their risk of complications.

About the study

Researchers in Copenhagen, Denmark, recruited 120 male and female smokers (average age 65) who were scheduled for elective hip or knee replacement surgery. Patients were excluded from consideration for the study if their weekly alcohol intake exceeded 35 units.

Sixty participants were randomly assigned to receive smoking cessation therapy starting six to eight weeks before surgery. Smoking cessation therapy consisted of weekly meetings with a nurse who provided smoking cessation counseling and nicotine replacement products. The nurse also tested the air expired from patients' lungs for carbon monoxide to determine if they had begun smoking again. The other 60 participants were assigned to the control group, which received no smoking cessation therapy.

At the end of the study, the researchers compared which patients had postsurgical complications relative to their smoking status.

The findings

The rate of postsurgical complications in the smoking cessation group was 18% versus 56% in the control group. Specifically, the rate of wound-related complications in the smoking cessation group was 5% versus 31% in the control group. Although the average length of hospital stay in the smoking cessation group was 2 days shorter than the control group, length of hospital stay depends on individual hospital protocol, as well as a patient's condition.

There is a limitation of this study that should be considered along with the results. The people who quit smoking could also have made other changes to improve their overall health, such as exercising, eating more healthful food, getting more rest, or drinking less alcohol. Such changes could make them less likely to experience complications from surgery.

Nicotine replacement products for the smoking cessation group were provided free of charge by Pharmacia Upjohn, and the study was funded by the Danish Research Councils, the Danish Ministry of Health, and Director Danielsen's Foundation. These sponsors had no role in the research or publication process.

How does this affect you?

Should you quit smoking before you have surgery? Of course. Any time is a good time to quit smoking. Will quitting smoking reduce your risk of complications after surgery? The findings of this study and others indicate there's a good chance it might. And keep in mind that other factors—including diet, exercise, alcohol intake, and rest—can also affect your ability to recover from surgery.

This particular study showed a reduction in overall and wound-related complications in hip and knee replacement surgeries, but what about the risk of respiratory complications? In this study, smoking did not increase the risk of respiratory complications. Why? Probably because hip and knee replacement surgeries typically have a low rate of respiratory complications. However, numerous other studies show that smokers have an increased risk of respiratory complications in abdominal surgeries.