Cardiorespiratory effects of NIV-NAVA, NIPPV, and NCPAP shortly after
extubation in extremely preterm infants: a randomized crossover trial
Abstract
Objective: Investigate the cardiorespiratory effects of non-invasive
neurally adjusted ventilatory assist (NIV-NAVA), non-synchronized nasal
intermittent positive pressure ventilation (NIPPV), and nasal continuous
positive airway pressure (NCPAP) during the critical period shortly
after extubation. Hypothesis: Levels of non-invasive pressure support
provided and/or presence of synchronization can affect cardiorespiratory
parameters. Study design: Randomized crossover trial. Patient-subject
selection: Infants with birth weight (BW) ≤ 1250g undergoing their first
planned extubation were randomly assigned to all 3 modes following
extubation. Methodology: Electrocardiogram and electrical activity of
the diaphragm (Edi) were recorded during 30min on each mode. Analysis of
heart rate variability (HRV), diaphragmatic activity (Edi area, breath
area, amplitude, inspiratory and expiratory times) and respiratory
variability (RV) were compared between modes. Results: 23 enrolled
infants had full data recordings and analysis: median [IQR]
gestational age = 25.9 weeks [25.2-26.4], BW = 760g [595-900],
and post-natal age 7 [4-19] days. There were no differences in HRV
parameters between modes. During NIV-NAVA and NIPPV, diaphragmatic
activity was significantly lower and RV higher than NCPAP. Delivered
peak inflation pressures (PIPs) were lower during NIV-NAVA than NIPPV
(14 cmH2O [13-16] vs cmH2O 16 [16-17]; p<0.001).
However, due to a significantly higher proportion of assisted breaths
(99% [92-103] vs. 51% [38-82]; p<0.001) NIV-NAVA
provided a higher mean airway pressure (MAP)(9.4 cmH2O [8.2-10.0]
vs. 8.2 cmH2O [7.6-9.3]; p=0.002). Conclusions: NIV-NAVA and NIPPV
applied shortly after extubation were associated with positive
cardiorespiratory effects. This effect was more evident during NIV-NAVA
where patient-ventilator synchronization provided a higher MAP with
lower PIPs.