In asthma patients using a metered dose inhaler (MDI) of a beta-2 agonist immediately prior to death, the possible involvement of beta-2 agonist side-effects in cardiopulmonary arrest remain unclear. Two cases of nearfatal asthma were transfered to our hospital. In the first case, a 20-year-old female was being treated with a tulobuterol MDI and suffered an episode of sudden-onset asthma. In the second case, a 16-year-old male was being treated with a procaterol MDI and suffered an episode of slow-onset asthma. After resuscitation, the adequately oxyganated patients were treated with a procaterol MDI using a dose large enough to reduce airway pressure and PaCO2. In the first case, normal breathing was quickly resumed. In the second case, however, five days of procaterol MDI use and intravenous steroids were required before normal breathing was resumed. The decrease in arterial potassium ions (less than 3mEq/l) as a result of frequent procaterol inhalation produced no clinically significant arrhythmias in either case. In conclusion, the patients did not experience any adverse cardiac events while adequately oxygenated despite the frequent inhalation of procaterol.
