Page 808 - Cardiac Nursing

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784 PA R T V / Health Promotion and Disease Prevention
lipoprotein. Nicotine is also responsible for the increased platelet smoked. Smoking cessation also lowers the overall risk for stroke to
aggregation and hypercoagulability found in smokers. In addition, that of a nonsmoker within 5 to 15 years of abstinence. 26
it leads to increased production of catecholamines, which in turn Because the overall death rate and rate of reinfarction is higher
increases blood pressure, heart rate and contractility, and systemic in patients with established CHD, intensive smoking cessation in-
vascular resistance, all of which result in increased myocardial oxy- tervention should be directed to this population. Nurses who pro-
gen demand. 25,27 Unfortunately, meeting this demand is difficult vide care for patients with CVD in all practice settings must not
because cigarette smoking constricts large and small epicardial ar- miss the opportunity to encourage smokers to quit at every en-
teries and coronary resistance vessels, leading to a decrease in coro- counter. In addition to the smoking cessation efforts of public ed-
nary blood flow. 28 In fact, in a study of patients with established ucation, commercial programs, and worksite health promotion,
CHD, Barry et al. 29 found that continued cigarette smoking was efforts to assist patients who have manifestations of CHD in the
related to a 12-fold increase in the amount of total ischemia daily. primary care setting are worthwhile.
Episodes of ischemic ST-segment depression occurred 3 times as
often, and the duration was 12 times longer in smokers compared
with nonsmokers (median duration of 24 min/24 h vs. 2 min/24 h). THEORETICAL FRAMEWORK
This increased ischemia may be related to the increased probabil- FOR SMOKING CESSATION
ity of recurrent coronary events in people who smoke. The increase
in heart rate may also lead to endothelial injury, myocardial is- The model we advocate for smoking cessation is the self-efficacy
chemia and MI, arrhythmias, and sudden death. 25 model based on social cognitive learning theory by Bandura. 34
Carbon monoxide interferes with oxygen transport, leading to Self-efficacy, in the case of smoking cessation, is defined as the
a reduced supply of oxygen to the tissues, and, more important, to smoker’s level of confidence that he or she could refrain from
the myocardium at a time when the demand is high because of a smoking in various challenging or “risky” situations such as social
higher heart rate. 26 Carbon monoxide interferes with the oxygen- situations (with friends in a cafe, when someone offers them a cig-
carrying capacity of red blood cells by binding to hemoglobin, arette), emotional situations (when feeling tense or depressed), and
thereby reducing the amount of hemoglobin available for binding habitual–addictive situations (when desiring a cigarette or when
with oxygen and by impeding oxygen release from hemoglobin. 25 they are experiencing withdrawal symptoms). 35 The belief is that
Carbon monoxide also increases the permeability of endothelial as risky situations are identified, strategies can be developed by the
membranes, resulting in increased uptake of cholesterol that leads patient in conjunction with his or her health care provider that will
to atherogenesis. 27 help the patient to either avoid or cope with a given situation. Low
When the number of cigarettes smoked daily, the total number self-efficacy is a strong predictor of relapse to smoking 16,36 ; there-
of years of smoking, the degree of inhalation, and the age of smok- fore, it behooves the health care provider to assess self-efficacy and
ing initiation are considered, the risk for development of CHD is provide coping skills and strategies to help the smoker successfully
found to increase with increasing exposure to cigarette smoke. navigate those situations where they are most at risk to smoke.
Overall, cigarette smokers have a two- to four-fold greater incidence Self-efficacy in various situations, however, is easily assessed in
of CHD than do nonsmokers, and cigarette smokers have a 70% the clinical setting. It has recently been hypothesized, however, that
greater death rate caused by CHD than do nonsmokers. Cigarette self-efficacy is intertwined with the patient’s smoking behaviors
smokers also experience a two- to four-fold greater risk of sudden and fluctuates over the course of the quit attempt. In other words,
death than do nonsmokers. 27 The damage caused by cigarette when the patient is initially attempting to quit, self-efficacy may be
smoking is not restricted to the heart alone. Cigarette smokers have low to moderate; as the patient successfully abstains from smoking,
a higher incidence of arteriosclerotic peripheral arterial disease and self-efficacy increases; self-efficacy may then decrease with a relapse
more severe atherosclerosis of the aorta than do nonsmokers, 26 as and increase with renewed cessation. This cycle would continue to
well as an increased rate of stroke and cerebrovascular disease. 27
fluctuate until permanent smoking cessation has been achieved
which would lead, theoretically, to continuously high self-efficacy.
BENEFITS OF Unfortunately, self-efficacy has rarely been measured more than
SMOKING CESSATION once or twice in a clinical trial, so this hypothesis requires further
17
testing. In the mean time, however, self-efficacy can be used clin-
ically to help guide the intervention and is especially helpful in re-
The health benefits of smoking cessation on the cardiovascular lapse prevention. The identification of risky situations, strategies to
system are well documented. The increased tendency to throm- deal with risky situations, and relapse prevention are discussed in
bus formation, coronary artery spasm, arrhythmias, and reduced greater detail in the section titled “Relapse Prevention.”
oxygen supply are likely to reverse in a short time. 30 For exam-
ple, evidence suggests that quitting smoking after an initial MI
decreases a person’s risk of death from CHD by at least 50% in SMOKING CESSATION
the first year after quitting. 31
This decline in risk appears to be independent of the severity of INTERVENTIONS IN THE
the MI. 32 In addition, reports from the Coronary Artery Surgery CHD POPULATION
Study (CASS) indicate that smoking cessation significantly improves
survival for people of all ages, including those older than 70 years. 33 The recent trials have had larger study populations, used more
In fact, after 1 year of abstinence from smoking, the excess risk of clearly defined definitions for abstinence, and saliva or serum co-
CHD related to smoking is cut in half and then gradually continues tinine levels or expired carbon monoxide levels have been used to
to decline over time. After 15 years of abstinence, the former smoker biochemically verify nonsmoking status. Only recently have
has achieved a risk level similar to that of a person who has never randomized clinical trials been conducted in women with