[Evaluation of mechanical ventilation in meconial aspiration syndrome].

Twenty seven newborn with serious meconial aspiration syndrome are studied. Two groups are stablish weather they require or not mechanical ventilation during evolution. When comparing various perinatal and clinical data, only the Silverman test showed statistically significant differences; pH and gases in blood during the first hours of life did not showed differences. Pneumothorax incidency in both groups was 33%. Twelve newborn required mechanical ventilation. The starting age was 24 hours of life range 3-54 hours. Most frequent indication was hipoxemia and apnea. Use of intermitent positive pressure improved PaCO2 with a light increase in PaO2 though it also increased alveolo-arterial oxygen gradient. Hipoxemia was the most relevant data in evolution of these patients. In seven cases continuous distending pressure was applied, with a light increase in PaO2 only in three patients. No patient suffered pneumothorax during mechanical ventilation. In patients with mechanical ventilation mortality was 25%. The possibility of an addition in certain cases of pulmonary hypertension with right-to-left shunting ductal and atrial is reported.