Performing Surgery On Smokers: What You Should Know
Patients who smoke have a higher risk for nonunion, non-healing wounds and other complications. Offering insights from the literature and their experience, these authors discuss the impact of smoking on surgical outcomes, timing issues with smoking cessation and pertinent pearls for improving surgical results in patients who continue to smoke.
Cigarette smoking is a major health and economic concern. Smoking is well known to have destructive effects on the respiratory, cardiovascular, endocrine and immune systems.1 The adverse health effects from cigarette smoking account for an estimated 443,000 deaths or nearly one of every five deaths each year in the United States.2,3 Smoking is the most preventable cause of premature death.
Smoking also has adverse effects on bone, decreasing calcium absorption and increasing bone resorption.4 It is a risk factor for the development of osteoporosis and fractures.4 Smoking has a negative effect on surgical outcomes. Multiple studies have shown that smoking has negative effects on bone, skin and wound healing as well as fusion procedures.5-9
Smoking contains over 4,000 chemicals of which only 109 are known chemicals, including nicotine, benzene, arsenic, hydrogen cyanide and tar. Nicotine negatively impacts fracture healing and bone fusion processes. Nicotine causes the release of catecholamines, which results in peripheral vasoconstriction that causes decreased blood flow, tissue ischemia and oxygen tension as well as depressed osteoblastic activity in bone.10-14 Cigarette smoke contains carbon monoxide, which causes tissue hypoxia by binding to hemoglobin to form carboxyhemoglobin. Carbon monoxide has a high affinity for oxygen and decreases the delivery of oxygen at a cellular level.15 Hydrogen cyanide inhibits the cellular respiratory enzymes.
Various authors have reported the adverse effects of cigarette smoking on wound and bone healing. Looking at the effects of smoking on lumbar fusions, Brown and colleagues found a 40 percent pseudarthrosis rate in smokers versus 8 percent in non-smokers.5 Ishikawa and co-workers found a 18.6 percent nonunion rate in smokers versus 7.1 percent in non-smokers receiving hindfoot fusion.6 Krannitz and coworkers found the healing time after Austin bunionectomy was delayed in smokers and even in secondhand smokers in comparison to non-smokers.7 The authors determined there was a 42 percent increase in the time to bone healing in the smoking group in comparison to the non-smoking group. Studies have shown that nicotine has detrimental effects on tendon to bone healing in a rat rotator cuff animal model.8 Daftari and colleagues showed that nicotine reduced the revascularization of cancellous bone grafts.9
Law and Hackham reported that postmenopausal bone loss is greater in smokers than in non-smokers and that tobacco smoking increases the lifetime risk of hip fracture in women by about 50 percent.15
In addition to its adverse effect on bone healing, smoking can result in an increased risk for infection after surgery. Smoking decreases cutaneous blood flow, which interferes with the natural process of wound healing and leads to an increased complication rate. The Lower Extremity Assessment Project (LEAP) study group showed that current smokers were more than twice as likely to develop an infection and 3.7 times as likely to develop osteomyelitis at the site of open tibial fractures.16