Pressure-support ventilation in children with severe asthma

Abstract

Objective: To review the efficacy of pressure-support ventilation in the management of children with status asthmaticus requiring mechanical ventilation.

Design: A case series.

Setting: A university hospital.

Subjects: Children requiring mechanical ventilation due to respiratory failure despite medical therapy during an episode of acute asthma.

Interventions: Mechanical ventilation with pressure-support ventilation.

Measurements and main results: Respiratory parameters (ventilatory settings, minute ventilation, respiratory rate, airway pressures) and blood gases were determined before, on initiation, and for 6 hrs after pressure-support ventilation. Spontaneous ventilation with an initial respiratory rate of 45 breaths/min (range 31 to 46) and an inspiration/expiration ratio (I/E) of 1:1.2 (range 1:1.1 to 1:2) was readily established in each patient. Arterial pH normalized (7.41, range 7.39 to 7.43) within 6 hrs (4.25, range 2 to 6) of the time at which ventilation was begun and the Paco2 decreased (p < .02) to 44 torr (range 39 to 47) (5.9 kPa, range 5.2 to 6.3) during pressure support ventilation.

Conclusion: Pressure-support ventilation permitted patient-cycled spontaneous ventilation in children with asthma. The ability of patients to determine their own respiratory pattern and to maintain forced exhalation during pressure-support ventilation may have important advantages in children with severe asthma who require mechanical ventilation.