Permissive Approach and Relationship to Outcomes of Infants <27 Weeks Gestation

Purpose: To determine profiles of carbon dioxide (PaCO2), pH and blood pressure (BP) in preterm infants (<27 weeks gestational age) in relation to mortality or any of three severe morbidities: (a) severe neurological injury, (b) severe retinopathy or (c) chronic lung disease. Methods: Profiles of pH, PaCO2 and BP in the first week and outcomes were analysed by dividing infants in three groups: (1) no morbidities (n=73); (2) with one/two morbidities (n=125), and (3) death or all three morbidities (n=56). Results: Mean pH were higher for Groups 1 and 2 compared to Group 3. Mean PaCO2 values were normal and lower for Group 1 compared to Groups 2 and 3. Mean BP was not different between three groups. Conclusion: Preterm infants with no morbidities had pH and PaCO2 values near normal range whereas infants with significant morbidities or mortality had values in the so-called "permissive" range.