The increase of oxygen requirement as index to identify the infants at high risk of pneumothorax during nasal continuous positive airway pressure

Abstract

Aim: The aim of this study was to evaluate the inspiration fraction of oxygen (FiO2) trend as an indicator of timing to suspend nasal continuous positive airway pressure (N-CPAP) and shift the babies to mechanical ventilation, in order to reduce the incidence of pneumothorax, comparing a similar population admitted in our division during the previous year.

Methods: Seventy-five newborns (mean gestational age 33.5 weeks, mean birth weight 2,072 g) admitted during 2003 in our Neonatal Intensive Care Unit, treated with Infant Flow System Nasal-CPAP, were included. Patients with more than 40% increase of the starting FiO2 in the first 24 h of treatment, were intubated and shift on mechanical ventilation. Seventy-seven infants, admitted during the previous year, with similar characteristics (mean gestational age 33.7 weeks, mean birth weight 2,047 g) were considered as control.

Results: Fifty-six neonates improved, 19 worsened and required mechanical ventilation. One of these developed pneumothorax (1.3%). Of the 77 infants admitted during the previous year, 26 worsened and were mechanically ventilated, and 8 developed pneumothorax (10.3%). The difference of incidence of pneumothorax was significant (P =0.0337).

Conclusions: An increase of FiO2 more than 40% of the initial value during the first 24 h of N-CPAP may be considered a useful marker to identify infants at high risk of pneumothorax.