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Millions of cigarette smokers undergo elective surgery each year. Efforts to help them quit smoking could improve immediate perioperative outcomes, such as those related to the cardiac and respiratory systems, and the healing of surgical wounds. Perhaps more importantly, the scheduling of elective surgery represents an excellent opportunity for smokers to permanently quit, with great benefit to their long-term health. Although it is difficult for smokers to quit, there are now several interventions of proven benefit that can more than double the chances of success. These include simple physician advice to quit, brief behavioral interventions that can be provided by physicians or other clinicians, and pharmacotherapy with drugs such as nicotine. Although specific strategies tailored for the surgical patient remain to be developed, there are steps that anesthesiologists can implement into their practices now that can help their patients quit smoking.
Approximately 23% of American adults smoke cigarettes, and one-third of these individuals will die prematurely because of their use of tobacco (1). Each year, millions of cigarette smokers require surgery and anesthesia. Two major benefits could result from efforts to help them quit smoking. First, smoking increases the risk of some postoperative complications, including pulmonary complications such as atelectasis and pneumonia, cardiovascular complications such as myocardial ischemia, and wound-related complications such as infection (2,3). Even temporary abstinence from smoking may reduce the risk of these complications and improve surgical outcomes. Second, a surgical episode may represent a "teachable moment" that encourages smokers to permanently quit, with great benefit to their long-term health. Many physicians are not aware that there has been great progress in recent decades in the treatment of tobacco dependence, as summarized in the most recent United States Public Health Service Guideline on Tobacco Use and Dependence (4) (available at http://www.surgeongeneral.gov/tobacco/). A primary recommendation of this report is to systematically identify all tobacco users who come in contact with the health care system, strongly urge them to stop, and aid them in doing so. The Guideline goes on to say that "...all physicians should strongly advise every patient who smokes to quit because evidence shows that physician advice to quit smoking increases abstinence rates" (4). The scheduling of patients for surgery is a point of contact that is currently not being exploited systematically for this purpose (5). Evidence demonstrates that even brief clinical interventions can significantly increase abstinence rates in a variety of settings (4). More intensive services, initiated by physicians and fully implemented by other providers, are even more effective. However, little attention has been paid to the role of anesthesiologists and surgeons in addressing tobacco use. Indeed, although many surgical specialists recognize the adverse effects of smoking both on short and long-term outcomes, few are familiar with methods to help their patients quit smoking (5). Moreover, some may have concerns with specific issues related to perioperative smoking cessation, such as whether it is safe for smokers to quit immediately before surgery and the safety of nicotine replacement therapy (NRT) in surgical patients. This commentary will briefly explore 1) why smokers should maintain perioperative abstinence from cigarettes for as long as possible, 2) why surgery is an opportune moment for smokers to quit permanently, and 3) how anesthesiologists can help them do so.
Smoking affects perioperative outcomes in two ways. First, smoking contributes to chronic illnesses such as coronary artery disease, chronic obstructive lung disease, and many others that may increase the risk of perioperative complications. Second, some of the more than 3000 constituents of cigarette smoke, such as nicotine and carbon monoxide (CO), have acute physiologic effects that could plausibly contribute to risk. As a result, status as a current cigarette smoker is an independent risk factor for many postoperative complications (6,7); however, status as an ex-smoker is generally not such a risk factor, suggesting that preoperative abstinence from smoking can reduce risk. Although prolonged abstinence before surgery clearly can improve postoperative outcomes, the benefits of more brief periods of abstinence are less clear and, for most complications, the duration of abstinence needed to derive benefit remains to be defined. The best data exist for perioperative cardiac, respiratory, and wound-related complications, which all occur with increased frequency in smokers. Smokers are at increased risk for perioperative cardiac complications, in part because cigarette smoking increases the risk of developing cardiovascular disease (8). Recent smoking may also contribute to acute vascular events by promoting a hypercoagulable state, increasing myocardial work, decreasing oxygen delivery secondary to CO, causing coronary vasoconstriction, and releasing catecholamines (9). Constituents of cigarette smoke that may contribute to these effects include nicotine, CO (which can interfere with pulse oximetry), oxidant gases, and polycyclic hydrocarbons. As a result, smoking acutely decreases exercise capacity and relatively brief abstinence improves it (10). In smokers, expired CO concentration, an indicator of recent smoking, is correlated with the frequency of significant ST depression during general anesthesia (11). Thus, although the period of abstinence needed to reduce perioperative risk is not known, even relatively brief preoperative abstinence may be beneficial. Smoking is also a risk factor for postoperative pulmonary complications, in part because smoking causes chronic pulmonary disease (6). Acute effects of smoke on ciliary function, the activity of airway efferent nerves, and pulmonary immune function may also contribute to complications. Smoking cessation improves pulmonary function, but this benefit may take several weeks or months to become apparent. Likewise, it may take a similar period of abstinence before a reduction in postoperative pulmonary complications is observed, with available studies estimating that at least 2 mo of abstinence is required before risk diminishes (6,12,13). Surgeons have long recognized that the healing of surgical wounds may be impaired in smokers, especially after procedures such as face lifts that require wide undermining of skin flaps (14). Possible mechanisms include a reduction in tissue oxygenation caused by chronic changes in microvasculature or carboxyhemoglobinemia or effects on immune function. These factors can cause wound dehiscence and infection. Also, bone healing may be impaired in smokers undergoing orthopedic procedures (15). Preoperative smoking cessation can dramatically decrease the frequency of wound-related complications (7); the duration of abstinence necessary for this benefit is not known but it appears to be <4 wk (16).
Both patients and physicians may have concerns that brief preoperative abstinence may actually be harmful (13) for at least two reasons. First, many smokers report that respiratory symptoms, such as cough and sputum production, actually increase over the first few weeks after quitting. This may explain why it takes several weeks of abstinence before a reduction in postoperative pulmonary complications is observed (6,12). However, abstinence within a few weeks of surgery does not significantly increase the rate of complications (6,12). Thus, fear of worsening pulmonary outcomes should not discourage physicians from urging their patients to quit regardless of the anticipated duration of preoperative abstinence. Second, many smokers view cigarettes as a tool to manage stress, and they may be reluctant to abstain at a time when they face the considerable stresses associated with surgery. Furthermore, nicotine is highly addictive and nicotine withdrawal can manifest several unpleasant symptoms, including irritability, restlessness, sleep disturbances, and depression, all of which could potentially complicate postoperative recovery. However, recent work (17) demonstrates that smokers report no greater increases in psychological stress over the perioperative period than do nonsmokers, nor do they consistently develop symptoms of nicotine withdrawal. Thus, patients (and their physicians) can be reassured that craving for tobacco will not routinely hamper their recovery if they remain abstinent. In addition, NRT can be used to help manage any withdrawal symptoms that do occur.
A "teachable moment" is an event that motivates individuals to adopt health behaviors that reduce risk (18). There is strong evidence that the concept applies to smoking cessation, as events such as pregnancy, disease diagnosis, and hospitalization are associated with increased rates of spontaneous smoking cessation compared with the rate in the general population. In hospitalized patients, it appears that the chances of quitting increase with the intensity of medical interventions. For example, one study found that of smokers undergoing cardiac interventions, 55% of those undergoing coronary artery bypass grafting, 25% of those undergoing angioplasty, and 14% of those undergoing only angiography were abstinent 1 yr after the intervention, a significant difference that persisted even after adjustment for severity of disease (19). For patients scheduled for elective surgery, those undergoing more extensive interventions (for example, those undergoing inpatient versus outpatient procedures) have a greater likelihood of spontaneously quitting after surgery (17). Thus, elective surgery can serve as a teachable moment as defined. In addition, as a result of smoke-free policies in United States (US) health care facilities, some period of abstinence is mandatory, such that all smokers must at least temporarily address their tobacco dependence. Effective tobacco interventions could dramatically impact the long-term health of the millions of smokers who undergo surgical procedures in the US annually. In addition, considering that prevalence rates of smoking are even higher in many other countries, the application of effective interventions worldwide could represent a significant contribution to world public health.
Most smokers want to quit but find it very difficult to do so. Approximately 70% of smokers report wanting to quit, and more than 50% of them make a quit attempt each year, but most attempts are not successful (4). Nonetheless, millions of people have succeeded in quitting, usually after multiple attempts. A meta-analysis sponsored by the United States Public Health Service screened more than 6,000 articles and was used to formulate practice recommendations based on expert panel opinion (4). The efficacy of several interventions is supported by multiple randomized clinical trials (Fig. 1). Most of these trials have involved the general ambulatory population, and very few have specifically examined surgical patients (20). However, several trials have examined the role of tobacco interventions in hospitalized patients and found similar results (21). These interventions can be categorized as using counseling (i.e., information exchange with patients) or pharmacotherapy.
Several principles are apparent from the evidence regarding the role of counseling in promoting smoking cessation (4). Physician advice to stop smoking increases quit rates. Although the evidence supporting the role of nonphysician clinicians (such as nurses) is less available, it appears that advice from these providers is also effective. Thus, even if clinicians do nothing else, smokers should be advised to quit at every opportunity. Brief counseling (<3 min) regarding smoking cessation provided by clinicians will further increase the rate of abstinence. More intensive interventions are even more effective, and there is a dose-response relationship between the total time spent in interventions and efficacy. These interventions can be delivered by a variety of providers with equal effectiveness. Many different formats of interventions are effective, including telephone counseling, group counseling, and individual counseling. In fact, the use of multiple formats increases efficacy. Components of effective interventions include assisting the patient in devising a personalized quit plan, providing practical problem solving skills, helping the patient obtain social support (e.g., from a spouse), and providing supplemental materials (e.g., brochures, etc.). Therapy is effective in both genders and across age groups and different racial and ethnic backgrounds. Pharmacotherapy is an important element of strategies to help smokers quit (22). The use of these medications approximately doubles the rate of abstinence. Nicotine derived from tobacco use can be replaced using several different delivery systems, including gum, inhalers, nasal spray, patches, and lozenges. All systems are effective in promoting cessation and each has potential advantages. For example, patches need only be applied once daily, compared with other formulations that need to be administered several times throughout the day. Conversely, some patients prefer to titrate their nicotine levels more precisely using the other delivery systems. NRT is generally well tolerated, with the predominant side effect consisting of local irritation at the site of delivery. Nicotine gum, patches, and lozenges are available without a prescription in the US. Other medications also are useful in promoting cessation. Sustained release bupropion, also used as an antidepressant, is approved by the Food and Drug Administration (FDA) for this purpose. Side effects include insomnia and dry mouth. Unlike nicotine replacement, patients should begin taking bupropion for 12 wk before they quit smoking. Clonidine is also effective, although it has not been FDA approved for this indication and side effects may limit its application.
There are two primary concerns with using NRT in surgical patients: the effects of nicotine on cardiovascular function and its effects on wound and bone healing. Although the effects of NRT on cardiac function have not been studied specifically in surgical patients, much is known about the safety of NRT in ambulatory patients with coronary artery disease. NRT does not increase the frequency of cardiac events in cigarette smokers with coronary artery disease, even if they continue smoking (9). NRT may even reduce cardiovascular risk if cigarette consumption is reduced but not eliminated. For example, NRT significantly decreases the extent of exercise-induced myocardial ischemia assessed by exercise thallium imaging in smokers with coronary artery disease (23). These results suggest that the benefits of NRT to help patients with coronary heart disease stop smoking outweigh the risk of continued smoking and support the concept that components of cigarette smoke other than nicotine, such as CO, contribute to adverse cardiac effects. Animal experiments support the clinical observation that cigarette smoking can impair wound and bone healing. For example, the survival of skin flaps that require wide undermining is decreased in animals exposed to smoke-filled chambers compared with smoke-free control animals (24). In these studies, it is not possible to determine which constituents of cigarette smoke are responsible for these effects. Several studies have shown that nicotine itself can impair wound healing in experimental animals (25). However, most studies use nicotine doses far in excess of those provided by NRT in humans, doses often sufficient to cause anorexia and weight loss. One important study (16) showed that quitting smoking dramatically decreased the incidence of surgical wound infection in humans; this benefit was observed whether or not the subjects used NRT to promote cessation. Thus, as in the case of cardiovascular function, avoidance of the other constituents of cigarette smoke is beneficial, even when nicotine is continued. Although more studies need to be performed specific to the surgical setting, available evidence does not support a detrimental effect of NRT in surgical patients, especially when compared with the consequences of continued smoking.
Given factors such as the time pressures associated with current practice, often associated with limited preoperative patient contact with an anesthesiologist, implementation of tobacco interventions poses very real challenges. Ideally, the interventions provided by anesthesiologists should be just one component of a comprehensive approach that includes systemic approaches such as collaborations with other health care providers. Given their role as perioperative physicians, anesthesiologists should at least be supportive of these efforts if they do not take a leading role. Although much more research is needed regarding how best to implement systems to help surgical patients quit smoking, in the meantime there are steps that all anesthesiologists can take today to help their patients quit. For primary care physicians, components of clinical interventions have been codified as the "5 As": Ask about tobacco use, Advise to quit, Assess willingness to make a quit attempt, Assist in quit attempt, and Arrange followup. Even with limited preoperative patient contact, anesthesiologists can perform these first three intervention elements as part of their preoperative visit.
Advise.
Assist.
Depending on practice settings, there may be other opportunities to intervene. If the patient is seen before the day of surgery, more intensive interventions can be administered, including more extensive counseling and the preoperative initiation of pharmacotherapy. If anesthesiologists see patients postoperatively before discharge from the facility, this provides an excellent opportunity to reinforce the stop smoking message, and ensures that referral to appropriate resources is made. If these opportunities for intervention are combined with other physician contact inherent in the surgical process, including the surgeons preoperative and postoperative visits and interventions by other clinicians, multiple reinforcing messages could have a powerful effect on smoking behavior, both in the immediate perioperative period and in the long term. Indeed, as perioperative physicians, anesthesiologists may be uniquely qualified to develop and lead multidisciplinary tobacco interventions by the surgical team.
Anesthesiologists do not hesitate to insist that patients change their behavior when they believe that such changes will be beneficial. For example, we consistently force our patients to deprive themselves of food for a certain preoperative interval. Growing evidence suggests that smoking in the perioperative period is harmful. Even limited perioperative abstinence may be beneficial and should be strongly recommended by anesthesiologists. Perhaps more importantly, if anesthesiologists can take the next step to help their patients take advantage of the excellent opportunity to quit permanently, they can make a significant difference in the lives of their patients that extends far beyond the relatively brief perioperative encounter. The author thanks Drs. Richard Hurt, Lowell Dale, William Lanier, Michael Sarr, and David Danielson, and Mr. Kenneth Offord (all from Mayo Clinic, Rochester, MN), for their helpful suggestions, and Ms. Kay Eberman (Mayo Clinic Nicotine Dependence Center, Rochester, MN) for assistance designing Figure 2.
Supported, in part, by the Mayo Foundation. Accepted for publication January 25, 2005.
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