Hochfrequenzoszillation (HFO) bei Mekoniumaspiration und bei Bronchopulmonaler Dysplasie

Within one year 3 newborns with meconiumaspiration and 4 infants with bronchopulmonary dysplasia (BPD) were treated with HFP, synchronous with conventional ventilation (CMV). The entrance criteria were insufficient oxygenation (Po2/Fio2<50 mmHg) and/or CO2-elimination (>60 mmHg), respectively peak inspiratory pressure Pi>40 mmHg and mean airway pressure MAP>20 mbar during CMV. All three cases of meconiumaspiration have shown a striking improvement in oxygenation and ventilation, in one case starting from a disastrous situation with PCO2>90 mmHg, Po2 30 mmHg (Fi(o2) 100%). After a HFO period of 9 to 10 hours Pi, MAP and CMV-frequency could be reduced. The patients could be extubated after 1-2 weeks. In severe BPD only in one case continous improvement and extubation in the 4. week of live were possible. Here the pulmonary artery pressure in dopplerechocardiography slightly was elevated (30-35 mmHg). In a further case extubation was possible after several trials with HFO. Indeed chronic respiratory insufficiency, progredient pulmonary emphysema on x-ray and clearly elevated pulmonary artery pressure (>40 mmHg) persisted. In 2 further cases there was no longstanding improvement of ventilation. One child died after 8 months, one after 6 months. In both cases there was a right-to-left shunt over foramen ovale and pulmonary artery pressures at systemic level. HFO led to an improvement in oxygenation and ventilation in all three cases of meconiumaspiration and probably prevented a fatal outcome in one case. The effect seems to depend on improved secretolysis and gas exchange. The different effects in BPD depend on the degree of pulmonary damage and elevation of pulmonary artery pressure.