Lack of bronchodilator effect after administration of subanaesthetic concentration of isoflurane in mild asthmatic subjects challenged with methacholine

Isoflurane therapy for severe refractory status asthmaticus in children

OBJECTIVE

To describe the use of inhaled isoflurane in a series of children with life-threatening asthma.

DESIGN

Retrospective case series.

SETTING

Pediatric intensive care unit of a tertiary-care children's hospital. Ten children ranging in age from 1 to 16 years with 11 episodes of severe asthma requiring invasive mechanical ventilation in the pediatric intensive care unit over a 5-year period.

RESULTS

Isoflurane resulted in an improvement in arterial pH and a reduction in partial pressure of arterial carbon dioxide (PaCO(2)) in all the 11 instances. This effect was sustained in 10 cases and led to clinical improvement and rapid weaning from mechanical ventilation. One child failed to show sustained response and was placed on veno-venous extracorporeal membrane oxygenation. One child died secondary to anoxic brain injury sustained prior to hospitalization. Hypotension was the major side effect, and occurred in 8 children necessitating vasopressor support.

CONCLUSIONS

Isoflurane improves arterial pH and reduces partial pressure of arterial carbon dioxide in mechanically ventilated children with life-threatening status asthmaticus who are not responsive to conventional management.