It depends on what kind of surgery you are having
The nicotine in the smoke is the culprit because it decreases blood flow in the skin by constricting the vessels. Studies have shown that if a smoker avoids all nicotine products - gums, patches, AND SECOND HAND SMOKE for one month before and one month after surgery, their risk of healing problems is reduced substantially but not quite to the level of a non-smoker.
The surgeries where the risks for smokers are highest are those in which the skin is undermined and tightened to achieve the desired effect. These include breast lifts and reductions, tummy tucks, and facelifts. Smokers should not have any of these surgeries until they are totally off all nicotine as above!!!
Smoking has several effects on the skin, all bad.
First is the acute nicotine vasoconstriction. This is unfortunately also present with nicotine gums and patches. It causes the blood vessels to shrink, reducing blood flow. In plastic surgery terms, the operated areas are suddenly deprived of blood. If a facelift patient were to smoke in the period shortly after surgery, the next day there might be dead skin present in front of the ears. Fortunately the short term effects of nicotine can be avoided by stopping smoking.
The second effect is chronic. Hardening of the arteries occurs. Less blood flow gets to the tissues. Surgeries that a patient would normally tolerate could result in complications. Atr particular risk are breast lifts, facelifts, grafts such as fat injection of LiveFill and tummy tucks.
The third effect is overall surgical risk. Smokers are at risk of having heart attacks, strokes, pneumonia, and every type of surgical complication, probably due to both of the effects above. Although I have not seen scientific studies of the next point, smokers tend to have yellowish unhealthy appearing tissues.
This does not mean that smokers can't have surgeries, just that they must stop smoking usually for 4 weeks before and 4 weeks after surgery, and accept that they are at greater risk for complications than nonsmokers. Their surgeries must also be done more conservatively.
Smoking and Plastic Surgery: Complications and Smoking Cessation
Tobacco emits dozens of known chemicals while burning. Nicotine, among others, is a potent vasoconstrictor to the blood vessels. In other words, the blood vessels spasm when they are exposed to nicotine, whether through cigarettes or chewable nicotine.
This becomes important in plastic surgery when we have to rely on the blood vessels to feed the skin and tissue after an incision is made. If the blood vessels are in spasm, they will not provide enough blood to supply the tissues, hence the tissue will die.
A good physician should listen to you and thus you should have a clear discussion about smoking cessation prior to surgery. In that capacity, the plastic surgeon and patient should begin a behavior modification to stop nicotine intake at least one month prior to surgery.