European journal of pediatric surgery : official journal of Austrian Association of Pediatric Surgery ... [et al] = Zeitschrift für Kinderchirurgie
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Infants with congenital diaphragmatic hernia (CDH) die, because their lungs are hypoplastic and their pulmonary vascular resistance remains elevated after birth. In human newborns, it is difficult to appreciate the benefit of new therapeutic approaches, because the pathological findings are not uniform, the disease is rare and the clinical criteria for poor prognosis with conventional therapy are uncertain. To study the benefit of high-frequency ventilation (HFV) the use of Tolazoline in CDH, we created a diaphragmatic defect in sheep fetuses at 0.6 gestation and studied full-term newborns after a caesarian section. ⋯ Clinical and pathological findings of the lambs with CDH were very similar to severe CDH in humans with bilateral lung hypoplasia, severe respiratory distress, high pulmonary vascular resistance and severe hypoxemia. HFV dramatically improved CO2 elimination, allowed less aggressive ventilation, and was associated with higher flows and lower systemic and pulmonary vascular resistance. However, HFV did not improve oxygenation leaving the newborn with severe hypoxemia associated with massive intrapulmonary foramen ovale shunting from right to left.