Doctors strongly recommend stopping smoking at least eight weeks before surgery.
If you smoke, you will have much higher risks for serious complications during and after surgery. If you continue to smoke, you will be more likely to:
- starve your heart of oxygen
- form blood clots in your veins
- find it harder to breathe during and after surgery
- increase you risk of infection
- impair the healing of bones, skin and wounds
- change the breakdown of certain drugs in your body
Why does smoking cause these risks?
Nicotine in cigarette smoke increase your heart rate and blood pressure, making your heart work harder so that it needs more oxygen. Carbon monoxide in cigarette smoke competes with the oxygen in your blood. This makes it harder to get the oxygen you need for your heart and body. Chemicals in cigarette smoke make your blood thicker, stickier and more likely to clot.
Chemicals in cigarette smoke can paralyse and destroy the cilia in your lungs which work to keep your lungs clear. Smoking increases the amount of mucus in your lungs, and narrows your airways. It increases the likelihood that your airways and air sacs in your lungs will partially collapse, making it harder to breathe.
Smoking alters your immune system and you will have a higher risk for chest and wound infections after surgery. Smoking can slow down and interfere with the healing of bones, skin and other body tissues. You are more likely to have wound infection after surgery, longer healing times, problems with new scars opening up and bad scarring. Chemicals in cigarette smoke interfere with the rate at which certain drugs break down in your body.
What can I do?
You can greatly reduce these risks by stopping smoking, ideally at least eight weeks before surgery. You will be more likely to:
- have a faster recovery
- have better wound healing
- have a shorter stay in hospital
- not need intensive care
- not need further surgery.
Quitting completely is the only way to stop and reverse the damage done by cigarettes. Cutting down in the weeks before surgery does not appear to reduce the risks of wound or lung complications at all. You can cut down before stopping smoking completely, but the recovery of your body will only start from the time you stop completely.
After you quit:
- At 24 hours the nicotine and carbon monoxide from cigarettes will be mostly gone from your body. Even quitting 12 hours before surgery will improve your heart rate and blood oxygen levels.
- At 1 week the cilia in your lungs will have begun to recover and will start cleaning mucus out of your lungs.
- At 2 weeks your throat and the large airways in your lungs will be less reactive, causing less problems with breathing during surgery.
- At 3 weeks your body's ability to heal wounds will have begun to improve.
- At 4 weeks the small airways in your lungs will be working better, but will still improve over the next five months.
- At 6 weeks your lungs will produce a normal amount of mucus, which will help your breathing during surgery.
- At 8 weeks your risk of lung complications will be lower than a continuing smoker. Your blood will be less thick and sticky, and your blood flow will improve. Your risk of wound complications will be much less than a continuing smoker. Your immune system and response to anaesthetic drugs will also improve.
Your rate or extent of recovery may also depend on other things such as whether you already have an advanced smoking-related illness.
After surgery, it is important that you do not start smoking again, even if you only quit 12 hours before surgery. Allow your body to recover and heal properly. Smoking makes recovery harder by stressing your heart, affecting your blood pressure, reducing oxygen in your blood and body tissues and damaging your lungs.
Passive smoking and surgery
Children and adults exposed to tobacco smoke have more breathing difficulties after having a general anaesthetic drug than non-smokers who have not been passive smoking. Children affected by tobacco smoke have lower levels of oxygen in their blood after surgery.
Non-smokers should avoid other's tobacco smoke before surgery.