338 - Cutoff value of FiO2 for identifying early nasal continuous positive airway pressure failure in very preterm infants with respiratory distress syndrome: A retrospective study

Publication Number: 338.4149

Ting-An Yen, National Taiwan Univsertisty Children's Hospital, Sunnyvale, CA, United States; Hsin-Chung Huang, National Taiwan University Children's Hospital, Taipei, Taipei, Taiwan (Republic of China); Chien-Yi Chen, National Taiwan University Children's Hospital, Taipei, Taipei, Taiwan (Republic of China); Hung-Chieh Chou, National Taiwan University Children's hospital, Taipei, Taipei, Taiwan (Republic of China); Po-Nien Tsao, National Taiwan Univsersity Hospital, Taipei, Taipei, Taiwan (Republic of China)

Background: Nasal continuous positive airway pressure (NCPAP) is used for the initial management of premature infants with respiratory distress syndrome (RDS). Current recommendation to use FiO2 > 0.30 at 2 h of life as the predictor for later NCPAP failure and considering surfactant treatment. We investigated predictors of NCPAP failure in preterm infants born at < 30 weeks and to determine hour-specific cutoff values of the fraction of inspired oxygen (FiO2) for different gestational age groups.

Objective: To analyze factors and hour-specific FiO2 thresholds associated with NCPAP failure in preterm infants with RDS.

Design/Methods: This is a retrospective study, reviewing very preterm infants born at gestational age (GA) 23 + 0/7-29 + 6/7 weeks who required NCPAP upon admission to the neonatal intensive care unit (NICU) in a single tertiary hospital. We reviewed maternal obstetric history and the infants’ respiratory data (from birth to 72 hours of age) and outcomes at discharge. Multivariate logistic regression was conducted to identify the potential predictors of NCPAP failure. The hour-specific cutoff values of FiO2 were derived from receiver operating characteristic curves constructed during the first 4 h of the infants’ life.

Results: Among a total of 206 very preterm infants admitted to the NICU during the study period, 108 (52%) were initially managed with NCPAP. Of them, NCPAP failed in 27 (13 %) infants (median age, 6 h). These infants exhibited lower gestational age, birth weight, and Apgar scores and lower PaO2 (partial pressure of oxygen in the arterial blood) in first blood gas than did those for whom NCPAP was successful (Table1). Multivariate logistic regression revealed that the Gestational weeks and FiO2 requirement during the first 4 h of life was independently associated with NCPAP failure (Table 2). Hour-specific FiO2 cutoff values for CPAP failure were 0.30, 0.28, and 0.25 at < 1, 1 to 2, and 2–4 h of life, respectively. After subgroup analysis, the cutoff value of FiO2 was 0.28 for preterm infants born at 26–30 gestation (area under the curve [AUC]: 0.89–0.98). For infants born at < 26 weeks of gestation, the cutoff value was 0.25 (AUC, 0.69–0.77).(Table 3)

Conclusion(s): Hour-specific cutoff values of FiO2 during the first 4 hours of life could aid in predicting NCPAP failure in advance. Further research is needed to determine whether universal or customized FiO2 thresholds should be used to predict NCPAP failure in extremely preterm infants.

Characteristics of patients received successful and failed NCPAP (N = 108)
*Estimated using chi-square, Fisher’s exact, or independent samples t test.
NCPAP, nasal continuous positive airway pressure; PPROM, preterm premature rupture of membranes; SD, standard deviation; IQR, interquartile range; PEEP, positive end-expiratory pressure; PaO2, partial pressure of oxygen in the arterial blood; PaCO2, partial pressure of carbon dioxide in arterial blood; IVH, intraventricular hemorrhage; ROP, retinopathy of prematurity; BPD, bronchopulmonary dysplasia.
**The use of positive pressure ventilation (mechanical ventilation, NCPAP, or nasal intermittent positive pressure ventilation [NIPPV]) at 36 weeks of gestation was regarded as any ventilators use at 36 weeks of gestation.

Table 2 Multivariate analysis of NCPAP failure at different hours of age


Hour-specific cutoff values for FiO2 in predicting NCPAP failure
FiO2, fraction of inspired oxygen; AUROC, area under the receiver operating characteristic curve; GA, gestational age.