Efficacy and safety of a rapid-sequence metaproterenol protocol in the treatment of acute adult asthma.
A 6-month prospective study was performed to examine the efficacy and safety of a rapid-sequence nebulized metaproterenol regimen for the treatment of acute asthma in adults. Patients 18 years of age or older who were not pregnant and who had not received beta 2-agonist therapy were identified and started on a rapid-sequence metaproterenol regimen (15 mg) by the triage nurse. Pretreatment and posttreatment peak flow, respiratory rate, pulse rate, and blood pressure were documented. Patients also gave a pretreatment and posttreatment rating of the clinical severity of their attack using a 1-to-10 visual analogue scale. Fifty patients were entered into the study, with an average age of 38 years (range, 19 to 87 years). Data were analyzed using the Wilcoxon matched-pairs signed rank test. Patients showed statistically significant increases in peak flow (193 to 328 L/min, P < .00001) and systolic blood pressure (136 to 143 mm Hg, P < .0054). Statistically significant decreases were shown for respiratory rate (25 to 22 beats/min, P < .0001) and clinical severity (6.2 to 3.2, P < .00001). Thirty-three patients (71%) who completed the protocol experienced an increase in pulse rate. Ten (21%) had a pulse rate increase of more than 30 beats/min. Two (4.2%) had pulse rate increases of more than 40 beats/min. Four patients were removed after one or two nebulizers because of severe side effects. One patient's pulse rate increased to more than 200 beats/min. Although effective in reversing bronchospasm, the side effects of metaproterenol when used in rapid sequence are of major concern.
Jerrard
D A
DA
Division of Emergency Medicine, University of Maryland Medical Center, Baltimore 21201, USA.
Olshaker
J
J
Welebob
E
E
Caraballo
V
V
Hooper
F
F
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001249:Asthma / Q000188:drug therapy* / Q000503:physiopathology; D001794:Blood Pressure / Q000187:drug effects; D004417:Dyspnea / Q000188:drug therapy* / Q000503:physiopathology; D005260:Female; D006801:Humans; D008297:Male; D009921:Metaproterenol / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D008875:Middle Aged; D009330:Nebulizers and Vaporizers; D010366:Peak Expiratory Flow Rate / Q000187:drug effects; D011446:Prospective Studies; D011674:Pulse / Q000187:drug effects
D009921:Metaproterenol