Effects of Synchronization during Noninvasive Intermittent Mandatory Ventilation in Preterm Infants with Respiratory Distress Syndrome Immediately after Extubation

Background: Noninvasive ventilation is increasingly used in very-low-birth-weight infants (VLBWI) to reduce complications that occur with invasive ventilation. However, the physiological effects of synchronization during noninvasive nasal intermittent mandatory ventilation (IMV) have not been tested in VLBWI immediately after extubation. Objective: We aimed to study the short-term effects of synchronized nasal IMV (S-NIMV) compared to nonsynchronized nasal IMV (NIMV) on breathing effort as measured by phasic esophageal pressure (Pe) deflection, spontaneous respiratory rate (RR), gas exchange, cerebral tissue oxygen saturation (StO(2)) and intermittent episodes of bradycardia or hypoxemia in VLBWI recovering from respiratory distress syndrome (RDS). Methods: Fourteen VLBWI recovering from RDS were studied using a randomized cross-over design during both S-NIMV and NIMV (of 2 h each) immediately after extubation. Results: Phasic Pe deflection, spontaneous RR and transcutaneous PCO2 decreased significantly while transcutaneous PO2 and synchrony rate (defined as peak ventilator pressure delivered within the first half of spontaneous inspiration) increased significantly during S-NIMV compared to during NIMV. There was no difference in blood pressure, average arterial oxygen saturation (SpO(2)), cerebral StO(2), fractional tissue oxygen extraction of the brain and severe bradycardia (defined as time with a heart rate < 100 beats/min lasting >= 10 s) and in hypoxemic episodes (SpO(2) < 80%) between the two modes. Conclusion: Synchronization during nasal ventilation immediately after extubation in VLBWI recovering from RDS improved gas exchange and decreased the respiratory effort, and it could therefore be considered to provide a more efficient respiratory support and synchrony. (C) 2015 S. Karger AG, Basel