Surfactant replacement therapy: a multicentric trial comparing two dosage approaches.

In this study the results of two different initial doses (Group A: 200 mg/kg--82 patients; Group B: 100 mg/kg--83 patients) of a porcine surfactant were compared in the treatment of neonatal respiratory distress syndrome. Main entry criteria were: birth weight between 700 and 2,000 grams, need of mechanical ventilation, FiO2 > or = 0.60 to obtain a PaO2 between 50 and 80 mmHg (PaO2/FiO2 < or = 133.3 mmHg) and less than 15 hours of postnatal age. Two further 100 mg/kg doses could be given in both groups at 12 hours interval if FiO2 was > 0.40. Birth weight (Group A: 1,231 +/- 281 g. and Group B: 1,324 +/- 355 g.), gestational age (Group A: 29.9 +/- 2.7 wk. and Group B: 30.6 +/- 2.6 wk.) and Apgar scores were similar in the two groups. Group A had a significantly higher mean PaO2/FiO2 ratio (p < 0.05) after 12 hours--178 (40-506) vs 133 (17-243) mmHg, before receiving a 2nd dose, after 24 hours--180 (17-431) vs 152 (39-360), and in the 3rd day--177 (40-333) vs 124 (24-249) and needed a lower FiO2 (p < 0.05) after 36 hours (0.47 +/- 0.20 vs 0.53 +/- 0.23) and on the 3rd day (0.51 +/- 0.23 vs 0.61 +/- 0.24). The mean peak inspiratory pressure was lower in Group A at 36 hours (17.5 +/- 4.5 vs 20.6 +/- 6.8) after the initial dose (p < 0.05). The time of exposure to high oxygen concentrations (FiO2 > or = 0.40) was lower in Group A--85 (3-643) vs 131 (3-672) hours; p < 0.05). Total amount of phospholipids given per patient was meanly 224 mg in Group A and 144 mg in Group B. Mortality was lower in group A but without significant difference (Group A: 17/82; Group B: 26/83). The analysis of the subgroup of babies with less than 1,500 gr. at birth showed a statistically significant difference in mortality (Group A: 15/70; Group B: 24/56; p < 0.02).

[Surfactant replacement therapy: a multicentric trial comparing two dosage approaches]. / Tratamento com surfactante pulmonar exógeno: um estudo multicêntrico comparativo entre duas diferentes doses iniciais.

This is an interim analysis of a multicentric trial that took place in 7 Neonatal Units to compare two initial doses of exigenous pulmonary surfactant (100 mg/kg and 200 mg/kg of phospholipids)by using a porcine surfactant for the treatment of very severe Hyaline Membrane Disease. The initial higher dose produced better oxigenation of arterial blood, reducing the time in high oxygen concentrations,while retreatments were necessary in less than half of the infants receiving 200 mg/kg as initial dose. The protocol of this study allowed the administration of additional doses only when FiO(2) was equal or greater than 0.40 instead of > 0.21, as in a large study recently published, where the same initial doses were given. This resulted in more than 40% reduction in the amount of surfactant administered,with apparently similar clinical outcome.