Treatment of status asthmaticus with intravenous magnesium sulfate.

The bronchodilating effect of magnesium sulfate (MgSO4) was studied in two patients with status asthmaticus, who were intubated and mechanically ventilated by a respirator. Airway resistance was continuously monitored by the respiration-controlled interruption technique. After administration of 0.5 mmol/min MgSO4 intravenously, airway resistance decreased from 17 to 9, and from 13 to 8 mmHg/L/s in the two patients, respectively, and piping rales diminished or disappeared. We conclude that while corticosteroid therapy requires several hours to demonstrate significant effects in status asthmaticus, MgSO4 is of great benefit in the rapid improvement of airflow obstruction.