Alan K. Halperin

Use of emergency medical services by patients with decompensated obstructive lung disease

Little information is available about the risk of relapse when patients with decompensated obstructive lung disease are treated in an emergency department for dyspnea. The purpose of our study was to determine if the risk of relapse was related to the severity and type of airway obstruction or to the time and duration of treatment. Over a period of 29 months, 496 patients with decompensated chronic obstructive pulmonary disease (COPD), asthma, or both were seen in the ED of the Albuquerque Veterans Administration Medical Center. Of 868 visits in which patients were treated and released, 244 (28.1%) were followed by a relapse within 14 days. Those who relapsed had a slightly higher one-second forced expiratory volume at baseline than those who did not (50.1 +/- 22.2% versus 45.5 +/- 20.6% predicted, P = .054). For 94 patients (group 1), asthma was the exclusive clinical diagnosis, and all available pulmonary function tests showed a bronchodilator response. For 268 patients (group 2), COPD was the exclusive diagnosis, and all tests showed no bronchodilator response. One hundred thirty-four patients (group 3) were either diagnosed as having both disorders or had varying bronchodilator response on sequential testing. The risk of relapse for group 3 patients (35.6%) was higher than for those in groups 2 (23.1%, P less than .001) or 1 (19.7%, P = .001). The frequency of relapse was higher for nighttime than daytime visits (36.1% versus 24.5%, P = .006) and for weekend than weekday visits (33.6% versus 26.6%, P = .049). Prognosis did not vary with the season or duration of treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

The effect of antihypertensive medications on exercise performance: a review.

This review describes the effects of antihypertensive drugs on the performance of aerobic exercise. All available antihypertensive drugs lower blood pressure both at rest and decrease the rate of increase during exercise. However, they differ in their effects on exercise performance. The ideal antihypertensive agent should not have significant depressant effects on the myocardium, should not promote arrhythmias, should preserve the distribution of blood flow to exercising muscle, and should not interfere with substrate utilization. Diuretics, one of the most commonly prescribed class of antihypertensives, have few deleterious effects on exercise performance but have adverse metabolic effects; beta blockers have many adverse effects on exercise performance. Agents which have the least potential for adverse effects on exercise performance and metabolic effects are the converting enzyme inhibitors, calcium channel blockers, and alpha blockers, and central alpha agonists. The literature concerning each of these drugs is reviewed and recommendations are made for prescribing for the hypertensive who wishes to engage in vigorous exercise.

Treatment of decompensated chronic obstructive pulmonary disease in the emergency department--correlation between clinical features and prognosis.

STUDY OBJECTIVE Patients with decompensated chronic obstructive pulmonary disease (COPD) are at high risk of relapse after treatment in an emergency department. The purpose of this study was to determine if the risk of relapse correlates with the clinical features of the disease. PATIENTS Three hundred fifty-two patients with documented COPD who were treated for dyspnea in the ED of the Albuquerque Veterans Administration Medical Center over a three-year period. METHODS We reviewed the clinical features and pulmonary function tests of the patients, who were considered to have COPD if the baseline prebronchodilator one-second forced expiratory volume (FEV1) was less than 80% predicted, and less than 80% of the forced vital capacity and inhaled bronchodilators failed to increase the FEV1 to levels of more than 80% predicted. Visits for pneumonia, pneumothorax, pleural effusion, or pulmonary emboli were excluded. A relapse was defined as an unscheduled revisit to the ED within 14 days of initial treatment. Data were entered into a microcomputer data base and analyzed by a commercial statistical package. RESULTS Of 877 visits in which the patient was treated and released from the ED, 281 (32.0%) resulted in relapse and were considered unsuccessful Compared with successful visits, unsuccessful visits were characterized by a shorter duration of dyspnea (P = .002), a lower entry FEV1 (P = .027), a lower discharge FEV1 (P = .040), a greater number of treatments with nebulized bronchodilators (P = .009), more frequent use of parenteral adrenergic drugs (P = .006), and less frequent use of oral prednisone on discharge (P = .016). Patients with one or more relapse visits during the study period (relapsers) differed from nonrelapsers in several respects. Relapsers had a greater bronchodilator response on baseline FEV1 than nonrelapsers (P = .047). Nevertheless, relapsers required more bronchodilator treatments in the ED (P less than .001); were treated more frequently with parenteral adrenergic drugs (P less than .001), IV glucocorticoids (P less than .001), and oral prednisone (P less than .001); and recovered less of their baseline FEV1 (P less than .014). CONCLUSION Bronchodilator response on baseline pulmonary function testing appears to identify patients with COPD who have a poor prognosis after emergency treatment. Their poor response to intensive bronchodilator treatment suggests that loss of bronchodilator response may be involved in the pathogenesis of respiratory decompensation.