Exercise tolerance

Propranolol. Propranolol (Table 1), a Class II antiarrhythmic agent, is usefiil in the management of hypertrophic subaortic stenosis, especially for the treatment of exertional or other stress-induced angina by improving blood flow. The dmg can increase exercise tolerance in patients suffering from angina. Propranolol has been shown to have cardioprotective action in post-MI patients (37—39,98,99,108). 

Premature onset of certain diseases in addition to significant aggravation of symptoms and decreased exercise tolerance in healthy persons. 

TypeV Myophosphorylase deficiency, McArdle s syndrome Absence of muscle phosphorylase Diminished exercise tolerance muscles have abnormally high glycogen content (2.5-4.1%). Little or no lactate in blood after exercise. 

There are two common systems for categorizing patients with HF. The New York Heart Association (NYHA) Functional Classification (FC) system is based on the patient s activity level and exercise tolerance. It divides patients into one of four classes, with functional class I patients exhibiting no symptoms or limitations of daily activities, and functional class IV patients who are symptomatic at rest (Table 3-5). The NYHA FC system reflects a subjective assessment by a health care provider and can change frequently over short periods of time. Functional class correlates poorly with EF however, EF is one of the strongest predictors of prognosis. In general, anticipated survival declines in conjunction with a decline in functional ability. 

In addition to weight changes, a marked decline in exercise tolerance should also be reported to the HF care provider. 

The major outcome parameters focus on (1) volume status (2) exercise tolerance (3) overall symptoms/quality of life (4) adverse drug reactions and (5) disease progression and... 

If diuretic therapy is warranted, monitor for therapeutic response by assessing weight loss and improvement of fluid retention, as well as exercise tolerance and presence of fatigue. 

Bronchodilators are the mainstay of treatment for symptomatic COPD. They reduce symptoms and improve exercise tolerance and quality of life. 

The medications available for COPD are effective for reducing or relieving symptoms, improving exercise tolerance, reducing the number and severity of exacerbations, and improving quality of life. No medications presently available have been shown to slow the rate of decline in lung function. 

Pulmonary symptoms may include chronic cough, sputum production, and decreased exercise tolerance. 

Hirsch, A., Gervine, E., Nakso, S., Come, P., Silverman, K. and Grossman, W., The effect of caffeine on exercise tolerance and left ventricular function in patinets with coronary heart disease. Annals of Internal Medicine 110, 593-598, 1989. 

Left ventricular systolic dysfunction and symptoms such as dyspnea, fatigue, and reduced exercise tolerance... 

Other outcomes include improvement in exercise tolerance and fatigue, decreased nocturia, and a decrease in heart rate. 

Exercise tolerance (stress) testing (ETT) is recommended for patients with an intermediate probability of CAD. Results correlate well with the likelihood of progressing to angina, occurrence of acute MI, and cardiovascular death. Ischemic ST-segment depression during ETT is an independent risk factor for cardiovascular events and mortality. Thallium myocardial perfusion scintigraphy may be used in conjunction with ETT to detect reversible and irreversible defects in blood flow to the myocardium. 

Patients should also be asked about exercise tolerance. 

After initiation of antiinflammatory therapy or an increase in dosage, most patients should begin experiencing a decrease in symptoms within 1 to 2 weeks and achieve maximum symptomatic improvement within 4 to 8 weeks. Improvement in baseline FEVj or PEF should follow a similar time frame, but a decrease in BHR as measured by morning PEF, PEF variability, and exercise tolerance may take longer and improve over 1 to 3 months. 

Patients experiencing a COPD exacerbation may have worsening dyspnea, increase in sputum volume, or increase in sputum purulence. Other common features of an exacerbation include chest tightness, increased need for bronchodilators, malaise, fatigue, and decreased exercise tolerance. 

The goals of therapy are to prevent disease progression, relieve symptoms, improve exercise tolerance, improve overall health status, prevent and treat exacerbations, prevent and treat complications, and reduce morbidity and mortality. 

Chronic theophylline use in COPD has been shown to produce improvements in lung function, including vital capacity and FEVj. Subjectively, theophylline has been shown to reduce dyspnea, increase exercise tolerance, and improve respiratory drive. Nonpulmonary effects that may contribute to better functional capacity include improved cardiac function and decreased pulmonary artery pressure. 

As with other bronchodilators in COPD, parameters other than objective measurements such as FEVj should be monitored to assess efficacy. Subjective parameters, such as perceived improvements in dyspnea and exercise tolerance, are important in assessing the acceptability of methylxanthines for COPD patients. 

Therapy of congestive heart failure. By lowering peripheral resistance, diuretics aid the heart in ejecting blood (reduction in afterload, pp. 132, 306) cardiac output and exercise tolerance are increased. Due to the increased excretion of fluid, EEV and venous return decrease (reduction in preload, p. 306). Symptoms of venous congestion, such as ankle edema and hepatic enlargement, subside. The drugs principally used are thiazides (possibly combined with K+-sparing diuretics) and loop diuretics. 

Exposure to excess bromine in pool water (8.2 Bg/ml) was thought to be responsible for irritative skin rashes eye, nose, and throat irritation bronchospasm reduced exercise tolerance fatigue headache gastrointestinal disturbances and myalgias in 17 adolescents. Several had persistent or recurrent symptoms lasting weeks to months after exposure. Oral, inhalation, and dermal absorption may all have occurred under the exposure conditions. 

With once-daily dosing, 24-hour control is achieved by giving doses larger than necessary to achieve an immediate maximum effect. The maximum early effect on exercise tolerance occurs with doses of 50 to 100 mg, but the effect at 24 hours is attenuated, averaging approximately 50% to 75% of that with once-daily doses of 200 mg. 

Some ACEIs have demonstrated a beneficial effect on the severity of heart failure and an improvement in maximal exercise tolerance in patients with heart failure. In these patients, ACEIs significantly decrease peripheral (systemic vascular) resistance, BP (afterload), pulmonary capillary wedge pressure (preload), pulmonary vascular resistance and heart size and increase cardiac output and exercise tolerance time. 

Because of these interindividual variations in the kinetics of propranolol, the therapeutic dose of this drug is best determined by titration. End points of titration include relief of anginal symptoms, increases in exercise tolerance, and plasma concentration of propranolol between 15 and 100 ng/mL. For additional details on the pharmacokinetics of propranolol and other (3-receptor antagonists approved for clinical use in the treatment of angina pectoris, see Table 17.3 and Chapter 11. 

Mechanism of Action AnACE inhibitor that suppresses the renin-angiotensin-aldos-terone system and prevents conversion of angiotensin I to angiotensin 11, a potent vasoconstrictor may also inhibit angiotensin II at local vascular and renal sites. Decreases plasma angiotensin II, increases plasma renin activity, and decreases aldosterone secretion. Therapeutic Effect Reduces peripheral arterial resistance, pulmonary capillary wedge pressure improves cardiac output and exercise tolerance. Pharmacokinetics ... 

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