[Hypercapnic status asthmaticus. Rapid reversibility of hypercapnia under medical treatment].

Fifty-four episodes of hypercapnic status asthmaticus (Pa CO2 50 mmHg or more) were treated with intravenous theophylline (6 mg/kg over 30 minutes, then 1 mg/kg/hour), intravenous hydrocortisone hemisuccinate (1 g then 500 mg 4-hourly) rehydration and oxygen therapy at a sufficient rate to obtain a Pa O2 of 80 mmHg or more. As a rule, improvement was rapid with a significant decrease of mean Pa CO2 values from 61 +/- 14 to 44.5 +/- 11.5 mmHg (P less than 0.001) over 2 hours. In only 3 cases was mechanical ventilation necessary. An initially high Pa CO2 value is not an absolute indication of mechanical ventilation. This method remains exceptional and can be avoided in most patients by the emergency medical treatment outlined above.