145 - A Blinded Observational Pilot study to evaluate Edi metrics to better predict extubation readiness

Premature neonates requiring invasive mechanical ventilation are at risk for several adverse respiratory outcomes which are further associated with neurodevelopmental impairments.We try to limit duration of intubation and advocate for early safe extubation.However, quantifying optimal extubation readiness in premature neonates is a challenge with nearly 1/3 of neonates requiring reintubation within 7 days.The decision to extubate is based on clinical judgement leading to a high degree of subjectivity and variation in the decision making.Electrical activity of the diaphragm (EAdi), a measure of neural respiratory drive and inspiratory load, may be a useful predictor of extubation success in preterm neonates.

Objective:

a)Measure pre-extubation & post-extubation Edi metrics [Edi peak, Edi min, Delta Edi pressures] as they relate to successful vs unsuccessful extubation
b)Compare accuracy of pre-extubation Edi metrics to comprehensive clinical events and vital sign changes in predicting successful extubation

Design/Methods: This is a prospective observational pilot study.All infants admitted to NYU Langone Medical Center NICU requiring conventional mechanical ventilation were eligible.The Edi catheter is placed at time of intubation, ~6 hours prior to extubation, and for up to 48 hours post-extubation.Extubation failure is defined as reintubation within 48 hours.Patient cohort is divided into 2 groups: successful extubation group and extubation failure group.Clinical & Edi metric data will be collected during these time periods and compared between the 2 groups using student T test and a chi-square test.A P value of < 0.05 will be used to define statistical significance.   

Results: 11 preterm neonates were studied, 3 failed extubations & 8 neonates were successfully extubated.The successfully extubated group of neonates received more antenatal steroids (87% vs 0%: p< 0.05).The cohort of failed extubation were more tachypneic, requiring increased fio2 and worsening blood gas 12 hours post extubation. Six hours prior to extubation, there was increase in delta Edi (10.68 vs 6.11: p< 0.05) & a trend towards decrease in TV:delta edi ratio (0.61 vs. 2.78) in the cohort of failed extubation group (Table 2).  

Conclusion(s):

Subjects who failed extubation had a higher Delta Edi & lower mean TV:Delta Edi ratios 6 hours prior to extubation when compared to the successfully extubated group.This cohort of infants were also significantly tachypneic with worsening blood gas 12 hours post extubation.Edi measurements prior to extubation may be a useful adjunctive tool to aid clinicians when making extubation decisions.