Objective: Neurally adjusted ventilatory assist (NAVA) synchronizes spontaneous respiratory effort with mechanical ventilation. Electrodes detect the electrical activity of the diaphragm (Edi) and transmit this information to the ventilator, allowing the patient to determine their own respiratory rate (RR), peak pressures, and inspiratory and expiratory times in synchrony with the ventilator. The objective of this study was to evaluate if premature neonates ventilate as effectively on NAVA as compared to pressure control ventilation (PCV).
Study design: Five ventilated neonates were enrolled (gestational age 25-29 weeks). Each neonate was ventilated on NAVA for 4 h, then switched to PCV for another 4 h. The cycle was repeated three times. Ventilatory parameters were averaged every 30 min to collect eight time points for each ventilatory mode. Data were analyzed using the mixed effects model procedure, utilizing the least-squares means (P<0.05).
Result: When compared to PCV, neonates ventilated with NAVA had lower peak inspiratory pressures (PIP), fraction of inspired oxygen (FiO2), transcutaneous PCO2 Edi peak and RR. There was an increase in expiratory tidal volume (TV), compliance and Edi minimum. Despite lower PIP and RR, partial pressure of CO2 (PCO2) was lower when ventilated on NAVA. There was no difference in mean airway pressure.
Conclusion: Premature neonates ventilated with NAVA required less PIP, FiO2 and RR to achieve lower PCO2 and better compliance compared with PCV.