Inhaled albuterol and oral prednisone therapy in hospitalized adult asthmatics. Does aminophylline add any benefit?

STUDY OBJECTIVE: To determine the efficacy of intravenous aminophylline in the treatment of adult patients hospitalized for exacerbation of asthma. DESIGN: Randomized, double-blind, placebo-controlled trial throughout the study. SETTING: University Hospital Clinical Research Center. PATIENTS: Forty-four patients admitted from the emergency room with a primary diagnosis asthma; 39 patients completed the study. INTERVENTIONS: Patients received either intravenous aminophylline or placebo in addition to frequent nebulized albuterol; prednisone 0.5 mg/kg body weight every 6 h orally; and supplemental oxygen. Aminophylline infusion rates were adjusted to achieve serum theophylline concentrations of 10 to 20 micrograms/ml. Changes were made in placebo infusion rates to maintain the double blind design. MEASUREMENTS AND RESULTS: Forced expiratory volume in 1 s (FEV1) and other spirometric measurements every 8 h by a blinded investigator or trained respiratory therapist. Subjective patient response and duration of hospitalization were compared. No difference in spirometric measurements was observed between the two groups at any time point. On admission to the study, FEV1 in the placebo group was 41.5 (+/- 2.9) percent predicted and in the aminophylline group 34.7 (+/- 2.3) percent predicted (p = 0.08). At discharge, FEV1 was 70.4 (+/- 2.9) percent predicted in the placebo group and 63.7 (+/- 2.8) percent predicted in the theophylline group (p = 0.10). There was no difference in subjective patient rating or duration of hospitalization between the two groups (placebo 1.95 days and aminophylline 1.78 days, p = 0.51). CONCLUSIONS: Our results suggest that aminophylline therapy does not add significant benefit to other standard therapies in hospitalized adult asthmatic patients. Because of the risks and cost of aminophylline treatment in the hospital setting, further research is needed to determine if there are subgroups of adult asthmatics who may benefit from the addition of aminophylline to other standard optimal therapies.

The effects of encainide versus diltiazem on the oxidative metabolic pathways of antipyrine.

The effects of diltiazem and encainide on the pharmacokinetics and metabolism of antipyrine were compared in nine healthy male volunteers. Diltiazem 90 mg every 8 hours for 5 days decreased the oral clearance of antipyrine from 2.34 to 1.86 L/hour (p less than 0.05) and increased half-life from 12.7 to 15.9 hours (p less than 0.05). Diltiazem reduced the formation rate constants for 3-hydroxymethylantipyrine by 27% (p less than 0.05) and 4-hydroxyantipyrine by 37% (p less than 0.05). There was also a 21% reduction in the formation rate constant for norantipyrine (0.05 less than p less than 0.10). Encainide 25 mg every 8 hours for 5 days had no apparent effect on the oral clearance or half-life of antipyrine, or on the formation rate constants for metabolites of antipyrine. In contrast to a previously published report in rats, encainide, unlike diltiazem, does not inhibit the oxidative metabolism of antipyrine in humans.

Evaluation of pharmacists' practice in patient education when dispensing a metered-dose inhaler.

Improper inhalation technique with beta-agonist metered-dose inhalers (MDIs) decreases efficacy of the bronchodilator. The success of demonstrating the correct technique and the pharmacist's role in patient education has been reported. To obtain information regarding the routine patient education practice of pharmacists when dispensing a beta-agonist MDI (albuterol), the following study was performed. Fifty-two prescriptions for an albuterol MDI were presented to 52 randomly chosen community pharmacists in three Tennessee cities. Twenty-six independent and 26 chain pharmacies wer evaluated. Pharmacists' practice with regard to patient education, instruction, and demonstration of the correct usage of the MDI was observed and recorded. Overall, 13 percent of the pharmacists initially offered to educate the patient-investigator (PI) regarding the correct usage of the MDI without being asked for information. Fifty-three percent of pharmacists offered information only upon being asked specifically how to use the MDI. Of the pharmacists who offered to educate the PI, 71 percent discussed less than half of the eight steps correctly. Only 1 of the 52 pharmacists actually demonstrated MDI inhalation technique, and this in response to a request. No pharmacist asked the PI to perform the technique while he/she observed. No pharmacist offered information on delivery enhancement devices. Our results demonstrate that few pharmacists educate patients on the correct usage of an MDI, and that many pharmacists are not aware of the correct technique.