Evaluation of methods of assisted ventilation in hyaline membrane disease

Abstract

Two methods of providing assisted ventilation were compared in infants severely ill with hyaline membrane disease (HMD). 10 infants were assigned to each group. One group received ventilation with a volume-cycled respirator, and the other was ventilated using a pressure-limited ventilator and reversed I:E ratio. Both groups were well matched for severity of illness in terrms of pH and blood gases. pH and Po2 were quickly corrected by both ventilators. However, the pressurecycled ventilator group had higher survival and lower complication rates. Pao2 after one hour was substantially improved at the same F1O2 in the pressure-limited group and after 8 hours the F1O2 required -to maintain a Pao2 of 50-70 mmHg (6·6-9·3 kPa) was significantly decreased compared with the volume-cycled group. No effects on blood pressure were detected in either group. The study shows that the pressure-limited method is significantly better.