Efficacy, results, and complications of mechanical ventilation in children with status asthmaticus.

We have conducted a retrospective survey of 79 children out of a total hospital asthmatic patient population of 2,412, admitted over a 32 month period to the ICU for the management of severe status asthmaticus. All patients were in severe respiratory distress with CO2 retention; 19 required mechanical ventilation due to increasing fatigue and worsening bronchospasm, having failed to respond to either inhaled or IV bronchodilator therapy. All patients were ventilated at slow rates (less than 12 min) and their airway pressure (Paw) was deliberately kept below 45 cmH2O, while accepting a PaCO2 in the 45-60 mmHg range, as long as the pH was compensated. Although two patients developed pneumothoraces while on positive pressure ventilation, these were resolved without incidents. Five patients who had mediastinal or subcutaneous air leaks prior to intubation did not develop pneumothoraces. Following the initiation of mechanical ventilation, IV beta-agonist therapy was increased in order to reverse the bronchospasm and reduce the duration of mechanical ventilation. Mean duration of intubation was 42 hours. Fourteen of the 19 patients were weaned and extubated within 48 hours. All patients survived without sequelae. We conclude that a degree of controlled "hypoventilation" by deliberately choosing Paw less than 45 cmH2O can be successfully used to ventilate children with severe status asthmaticus with a reduced rate of pressure-related complications.