Which patients benefit from adding theophylline to beta 2-agonist treatment in severe acute asthma?

The aim of this investigation was to study whether certain patients benefit from adding theophylline to the beta 2-agonist treatment of acute asthma. The study group comprised 101 patients who were taking oral theophylline. The patients received inhaled salbutamol (albuterol) (0.15 mg/kg x 2) (n = 53) or IV salbutamol (5 micrograms/kg) (n = 48). Aminophylline (3 mg/kg) was infused intravenously 60 minutes after the start of the salbutamol treatment. The mean increase in peak flow (PEF) after the aminophylline infusion was 22 +/- 33 L/min or 4% +/- 6% of the predicted value (mean +/- SD). A change in PEF correlated negatively to plasma theophylline before treatment (P less than .01) and positively to a change in plasma-theophylline after treatment (P less than .05). All patients with an increase in PEF of more than 10% of the predicted value (n = 14) after the theophylline infusion had plasma-theophylline levels before treatment of below 7.5 mg/L (41 mumol/L). No significant difference in the change in PEF after the theophylline infusion was found between patients who had received inhaled or intravenous salbutamol. This investigation could indicate that IV theophylline as an additive to beta 2-agonist treatment should be reserved for patients who are either not taking theophylline or who have only taken a low dose before arriving for the emergency treatment of acute asthma.