Scheduled for surgery? Quit smoking to reduce the risk of complications

The Bottom Line

  • People who smoke cigarettes have a greater likelihood of having complications during and after surgery than non-smokers.
  • Quitting – even for a short time – reduces risks and increases the chance of a successful surgery and a faster recovery.
  • Smoking cessation treatments that include behavioural counselling can help people stop smoking prior to scheduled surgery.
  • Intensive programs (four weeks or longer) are most effective at helping people quit prior to surgery and be smoke free one year after surgery.

The health risks associated with cigarette smoking are numerous, serious and well-documented. Whether or not we smoke we all know it’s a dangerous habit and that there are many compelling reasons to quit. But here’s one we might not think of until faced with the situation: people who smoke are significantly more likely to experience complications after having surgery (1).   

Risks are greater because of how smoking affects the body, especially the heart and lungs. The presence of nicotine in the bloodstream puts extra strain on the heart during anaesthesia and surgery, while carbon monoxide in the blood interferes with the delivery of oxygen throughout the body – critical for proper healing (2). Smoking damages the lining of the lungs, putting people at higher risk for pneumonia and other breathing difficulties (3). Making matters worse, smokers have a weakened immune system so are less able to fight off infections resulting from surgery or that occur during recovery (4).

 A solution would be for people to stop smoking – for good – prior to having elective surgery, but as anyone who has tried to quit knows, it isn’t that simple. However quitting for even a short time – a day or two – may minimize potential problems during and after surgery (2;5). 

How can we encourage that? A systematic review of 13 randomized controlled trials sought to find out if pre-surgery smoking cessation treatments are effective in the short and long term, and if they result in fewer complications (6). The studies involved a total of 1,210 participants, all of whom were having elective surgery for a wide variety of health issues. They received behavioural treatments including face-to-face, telephone, or computer-assisted counselling that was either brief in nature (typically one short information session at least a few days before surgery) or intensive – weekly sessions over a period of four to eight weeks. Some participants were offered nicotine replacement therapy or other medications in addition to the behaviour treatments.

What the research tells us

There is modest evidence that pre-surgery behavioural treatments help people stop smoking, at least in the short term. Compared with the control group (little or no smoking cessation treatment), 12 more people out of 100 who received brief treatment, and 46 more people out of 100 who underwent intensive treatment, had stopped smoking at the time of their surgeries. The intensive treatment group also had considerably fewer post-surgery complications and were more likely to have abstained from smoking for the next year.

While the results indicate that intensive treatment to stop smoking should begin at least four weeks before a scheduled procedure, for best results and optimal health smokers are encouraged to take steps to quit as soon as possible, even before they ever need surgery! 

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Author Details


  1. Bluman LG, Mosca L, Newman N et al. Preoperative smoking habits and postoperative pulmonary complications. Chest. 1998; 113:883-9. 
  2. Pearce AC, Jones RM. Smoking and anaesthesia: preoperative and perioperative morbidity. Anesthesiology. 1984; 61:576-84. 
  3. Lourenco RV, Klimek MF, Borowski C.J. Deposition and clearance of two micron particles in the trachiobronchial tree of normal subjects – smokers and non-smokers. JCI. 1971; 50:1411-20.  
  4. Sorensen LT. Wound healing and infection in surgery:the pathophysiological impact of smoking, smoking cessation and nicotine replacement therapy: a systematic review. Annals of Surgery. 2012; 255:1069-79. 
  5. Kambam JR, Chen LH, Hyman SA. Effects of short-term smoking halt on carboxyhemoglobin levels and p50 values. Anesthesia and Analgesia. 1986; 65:1186-8. 
  6. Thomsen T, Villebro N, Moller AM. Interventions for preoperative smoking cessation. Cochrane Database Syst Rev. 2014; 3:CD002294.

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