Background Determining extubation readiness in preterm infants is often difficult, and infants who have respiratory failure and require reintubation incur additional morbidities. A heart rate characteristics index (HRC index or HeRO Score) developed for sepsis detection in VLBW infants has been shown to be associated with other adverse events including respiratory decompensation (Sullivan, J. Paediatrics 2014).

Objective Test the hypothesis that the HRC index predicts extubation failure in VLBW infants.

Methods We analysed all extubations within 3 weeks of birth for VLBW infants enrolled in a multicenter trial of HRC index monitoring (HeRO trial) randomised to the control arm (HeRO scores not displayed to caregivers).

Results There were 427 extubations in 365 VLBW infants. Excluding 20 infants who died within 3 days, 98 (24%) infants failed extubation, requiring reintubation within 72 h. Infants who failed extubation had significantly lower postmenstrual age (mean PMA 27.2 vs 28.6 weeks) and higher HRC index (2.2 vs. 1.5). Relative risk of extubation failure if PMA was <26 weeks or if HRC index was >1.0 were 2.3 and 2.2, respectively. HRC index added to PMA in predicting extubation failure, and infants <26 weeks PMA with HRC index >1.0 had 55% failure rate (Table).

Conclusion The HRC index adds to PMA for prediction of extubation failure in VLBW infants.