SELECTED ARTICLES FROM THE RECENT LITERATURE 2005

9/21/05

Airway changes in fatal asthma

Summary
Background - The duration of fatal asthma episodes falls into a bimodal pattern - a short duration (less than a few hours) and a prolonged duration before death. Are there airway pathologic findings that characterize the two temporal patterns of fatal asthma episodes?

Findings - James et al of the Sir Charles Gardner Hospital in Nedlands, Australia examined the pathology in these 2 temporal patterns of fatal asthma attacks in the Victorian asthma mortality study, based on the duration from reported onset of symptoms to time of death.

They found short course (< 3 hours duration) fatalities were characterized by more shortening of airway smooth muscle, higher ratios of neutrophils to eosinophils, and higher blood levels of albuterol than the longer duration (> 8 hours) cases. The latter cases were characterized by greater amount of mucus in the airway lumens.

The authors concluded that, in short duration fatal asthma attacks, acute airway narrowing is due predominantly to bronchoconstriction, possibly associated with altered inflammatory cell responses despite important in longer course fatal asthma episodes.

Reference
 Eur Resp J 2005;26:429-34

Editor's Comments
It has been generally recognized that some fatalities in asthma occur after a quite short duration episodes while in other cases, death occurs after much longer duration when the patient is no longer able to maintain the respiratory effort after ineffectual attempts. These findings suggest that the pathogenesis of short duration episodes is due to excessive shortening of airway smooth muscle, despite high levels of beta agonists, possibly associated with prominent neutrophil accumulation.

<-- BACK