Review of: Salo D, Tuel M, Lavery R, et al: “A randomized, clinical trial comparing the efficacy of continuous nebulized albuterol (15 mg) versus continuous nebulized albuterol (15 mg) plus ipratropium bromide (2 MG) for the treatment of acute asthma.” The Journal of Emergency Medicine. 31(4):371-376, 2006
The authors of this study attempted to determine if adding ipratropium bromide (Atrovent) to albuterol was superior in effect to albuterol alone, when both are given as a continuous non-stop nebulization for acute asthma attacks. Patients were randomized into two groups. During a two hour period, one group got 15 mg of albuterol, while the second group got 15 mg of albuterol and 2 mg of Atrovent nebulized. The primary outcome measure was peak flows measured at one and two hours.
Both the control group (albuterol alone) and the study group (albuterol plus Atrovent) had similar initial respiratory rates and peak flows. They all received oral prednisone at the outset.
At the one and two hour mark, they found no significant difference in peak flows of either group. Therefore, they concluded that adding Atrovent to a continuous neb is without significant benefit.
Several studies have shown added benefit of providing continuous nebs for bronchospasm, compared to repeated intermittent nebs. Most of the benefit is probably from less interruption in providing care that occurs when you provide a single neb, than when you evaluate a patient, find them still wheezing and then have to mix up another neb.
Atrovent has been proposed as an adjunct to the treatment of bronchospasm through its blunting of the parasympathetic nervous system, which allows the sympathetic beta agonist effect to be more effective. However, some studies indicate that the value of Atrovent is seen more often in older patients and those with COPD, because the parasympathetic nervous system predominates.
In this study, which was limited to asthma, the median age of the patients in both the study and control group was less than 40-years-old. Also, 95% of the patients were African American, which raises the question of racial differences in the pathophysiology for asthma.
While this study did not show a significant improvement, it may be that studies need to examine its use in older patients.