Background: The aim was to determine the effectiveness of continuous aminophylline infusion on refractory bronchospasm in long-term mechanically ventilated neonates.
Case report: Presented are seven newborns with gestational ages from 24 to 38 weeks and mean age at treatment of 29.7 days. All were mechanically ventilated from birth because of respiratory distress syndrome. Bronchospasm was diagnosed by wheezing, worsening of gas exchange, lengthening of expiratory time, and the need to modify the peak inspiratory pressure (PIP) to maintain the tidal volume. All patients had received conventional bronchodilator treatment for more than 24 hours before aminophylline treatment, without significant response. After discontinuation of previous bronchodilator drugs, an intravenous 6 mg/kg aminophylline bolus was administered over 20 minutes, followed by continuous infusions of 0.7 mg/kg/h for 12 hours and 0.35 mg/kg/h during the next 12 hours. Altogether, the treatment was carried out for 24 hours. Pulse-oximetry saturation (SpO(2)), transcutaneous pO(2)/pCO(2) (TcPO(2)/PCO(2)), heart rate, blood pressure, mean airway pressure (MAP), and fraction of inspired oxygen (FiO(2)) were recorded before and after the treatment. The SpO(2) (p<0.005) and TcPO(2) (p<0.002) increased significantly, while significant reductions in TcPCO(2) (p<0.00008) and FiO(2) (p<0.03) were observed. No signs of toxicity or significant differences in heart rate or blood pressure were reported. Mean serum aminophylline concentration resulted in therapeutic levels at both 12 and 24 hours.
Conclusions: It is suggested that continuous infusion of aminophylline is well tolerated and may prove useful in improving the gas exchange in long-term mechanically ventilated neonates with refractory bronchospasm.