Page 906 - Cardiac Nursing

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882 PA R T V / Health Promotion and Disease Prevention
levels, lipids, and blood pressure can be helpful in guiding treat- in people with diabetes. In diabetes, plaque formation is amplified
ment. Lifestyle interventions, including at least a 5% weight loss due to the propensity for platelet activation, aggregation, and hy-
and engaging in 150 minutes of physical activity a week, can stop percoagulation. Arterial stiffness and decreased compliance of the
the progression to diabetes. arterial wall increases systolic blood pressure and pulse pressure.
Pharmacologic interventions to prevent diabetes have also had These elevated pressures increase shear stress on the endothelium.
some success as evidenced by the Metformin arm of the Diabetes In type 2 diabetes, elevated systolic pressure is associated with
Prevention Program. In addition to the DPP, in the double-blind vascular events and left ventricular hypertrophy. In summary, hy-
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Study to Prevent Non-Insulin Dependent Diabetes Mellitus trial, pertension, endothelial dysfunction, inflammation, increased
participants with impaired glucose tolerance were randomized to re- thrombosis production, and arterial stiffness are all contributors
ceive either acarbose (a medication that decreases postmeal glucose to the high risk of cardiovascular complications associated with
by delaying the absorption of carbohydrates) or placebo. Over a diabetes. 13
3.3-year period, there was a 36% relative risk reduction in progres-
sion to diabetes. In addition, treatment participants experienced a
53% relative risk reduction in cardiovascular events. The results Manifestations of Macrovascular
from this trial highlight the importance of managing postprandial Disease in Diabetes
glucose levels. Other trials demonstrated a decrease in the progres- Coronary artery disease occurs in 9.1% of people with diabetes
sion to diabetes with the use of thiazolidinediones (TZDs). These versus 2.1% in the general population 40 and accounts for 56% to
studies include the Diabetes Reduction Assessment with Ramipril 60% of all deaths. There is still debate whether coronary artery
13
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and Rosiglitazone Medications and the Troglitazone in Prevention bypass grafting, aggressive risk factor management or percuta-
of Diabetes Study. 38 neous transluminal coronary angioplasty is the superior treatment
Given the predicted global epidemic of diabetes, health care for patients with diabetes. When completed, the Bypass Angio-
professionals are encouraged to identify high-risk patients and plasty Revascularization Study should provide some answers and
41
promote lifestyle changes to improve health outcomes.
help direct care for post-MI patients with diabetes.
Cerebrovascular accidents are more likely to occur in people
with diabetes at a younger age and when there is a history of my-
MACROVASCULAR ocardial infarction. Stroke occurs in 6.6% of the diabetes popula-
COMPLICATIONS OF DIABETES tion and 1.8% in persons without diabetes. Management includes
40
vascular surgery or management of risk factors, with a special focus
The NCEP III has termed diabetes a coronary heart disease risk on managing hypertension, smoking cessation, and initiation of an-
equivalent. 40 CVD is the major cause of mortality and morbidity tiplatelet therapy. 13
for individuals with diabetes and is the largest contributor to the Diabetes increases the risk of the development of congestive heart
13
direct and indirect costs of diabetes. 11 Given the prevalence and failure (CHF), especially in women; 7.9% of people with diabetes
severity, an understanding of the pathophysiology and manifesta- have CHF, versus 1.1% in the general population. 40 Possible mech-
tions of CVD will be presented. Risk reduction and treatment will anisms for this increased risk include decreased ventricular elasticity
be addressed in “Goals of the Diabetes Care” section. due to cross-linking of collagen, inflammatory cytokines, and oxida-
tive stress. Other risk factors include hypertension, hyperglycemia,
and endothelial inflammation. The end result is diminished relax-
Pathophysiology of Macrovascular ation of the ventricle and impaired diastolic filling, both of which in-
Disease in Diabetes crease the risk of developing CHF. 13
Peripheral arterial disease (PAD) affects approximately 20% to
Hyperglycemia is associated with defects in the vascular endothe- 30% of people with diabetes and is frequently under diagnosed
lium, the lining of the blood vessels, and chemical mediators that and under treated. 42 Assessment of PAD includes determining if
increase vascular dysfunction. Current research has shown that the the patient suffers from intermittent claudication and measuring
vascular endothelium is an active endocrine organ that secretes a ankle brachial index. Main risk factors for development of PAD
number of factors, which provide an environment that inhibits include tobacco use and diabetes. Since people with diabetes and
the adhesion of leukocytes, platelets, prevents clot formation, and PAD are at increased risk for lower extremity complications in-
inhibits vasopasm. 13 A bioactive substance of particular impor- cluding amputations and cardiovascular events, it is important to
tance is nitric oxide (NO). NO causes vasodilatation and platelet help patients identify and reduce vascular risk factors.
inhibition, reduces vascular wall inflammation, prevents vasocon-
5
striction and thrombus formation. However, in the presence of
cardiovascular risk factors and hyperglycemia, levels of NO are di-
minished and there is decreased vasodilatation in response to NO. NURSING MANAGEMENT
This defect contributes to the high prevalence of hypertension as- OF DIABETES
sociated with hyperglycemia.
Diabetes also increases the inflammatory response often seen Nurses are positioned to play a pivotal role in curbing the diabetes
in damaged vessels due to oxidative stress, diminished NO pro- epidemic. Nurses can initiate diabetes detection initiatives, such as
duction, and high postmeal circulating levels of FFAs. Inflamma- evaluation of all glucose levels in the hospital or outpatient set-
tory mediators enhance the creation of foam cells, decrease tings to find those who are undiagnosed. In the clinical setting,
plaque stability, and increase risk of plaque rupture triggering they can review patient’s history, symptoms, and lab values to de-
acute thrombotic events. Cardiovascular risk is closely linked to termine if they are at risk for prediabetes, undiagnosed diabetes,
the platelet dysfunction and coagulation disorders commonly seen or heart disease. Important nursing roles include explaining the