Abstract
To test the hypothesis that high-frequency ventilation may reduce the risk of barotrauma and thus the incidence of chronic pulmonary damage in preterm infants who need mechanical ventilation, we measured lung function before discharge in 53 infants who needed mechanical ventilation on the first day after birth and were randomly assigned to receive intermittent mandatory ventilation (n=26) or to receive high-frequency oscillatory ventilation (n=27). There were no significant differences between the groups in birth weight (mean ±SD: 1010±240 vs 1030±230 gm), gestational age (29.1±2.0 vs 28.9±2.1 weeks), initial ventilatory support (mean airway pressure 7.2±1.8 vs 8.1±2.1 cm H
2O; Flo
2 0.62±0.24 vs 0.75±0.22), duration of mechanical ventilation (median (range): 6 (1 to 61) vs 10 (1 to 50) days) and duration of oxygen therapy (13 (1 to 109) vs 27 (4 to 227) days) for the intermittent mandatory ventilation group and the high-frequency oscillatory ventilation group, respectively. At the time of testing, weight was 1830±340 vs 1830±290 gm, and age was 68±24 vs 70±31 days. Respiratory flows were determined by pneumotachygraphy, esophageal pressure through a water-filled feeding tube, and functional residual capacity by N
2 washout. Both groups had abnormal lung function with decreased lung compliance (1.65±0.51 vs 1.54±0.36 ml/cm H
2O) and elevated pulmonary resistance (102±24 vs 107±36 cm H
2O/L/sec). Functional residual capacity was in the normal range (30.6±6.0 vs 28.2±10.7 ml) in both groups. There were no significant differences in lung function between the two treatment groups. These results do not support the hypothesis that high-frequency oscillatory ventilation reduces the risk of lung damage in preterm infants.
