Effects of Neurally Adjusted Ventilation Assist (NAVA) and conventional modes of mechanical ventilation on diaphragm functions: A randomized controlled trial

Abstract

BackgroundBetter patient-ventilator interactions, during neurally adjusted ventilator assist (NAVA), are expected to result in lower rate of diaphragm dysfunction. ObjectiveThis study was planned to compare the rate of diaphragm dysfunction between the conventional modes of mechanical ventilation and NAVA. MethodsPatients who were initiated on mechanical ventilation for acute respiratory failure were randomized to continue either conventional mode of mechanical ventilation or switched to NAVA. The rates of diaphragm dysfunction were compared between two groups. ResultsThis study included 46 participants (male 30/46) with a mean age of 58 years. Mean APACHE II and SOFA scores were 15 and 3, respectively. The mean (SD) diaphragm thickness fraction in the conventional mechanical ventilation and NAVA group were 37.12% (18.48) and 39.27% (27.65), respectively. The diaphragm dysfunction was observed in 5 (22.7%) and 8 (34.7%) patients in NAVA and conventional arm, respectively. There was no statistically significant difference between the two groups (p-value = 0.37). Diaphragm excursion was better in the NAVA group as compared with the conventional mechanical ventilation group. Diaphragm thickness and thickness fraction were comparable between two groups. ConclusionSwitching from the conventional mode of mechanical ventilation to NAVA leads to statistically non-significant reduction in the occurrence of diaphragm dysfunction. Adequately powered studies are required to assess the exact role of NAVA on diaphragm functions.