The Science Journal of the American Association for Respiratory Care

2010 OPEN FORUM Abstracts


Cynthia C. White, Brandy Seger, Li Lin, Susan McGee, Lesley Doughty; PICU, Cincinnati ChildrenÂ’s Hospital Medical Center, Cincinnati, OH

Background: Neurally Adjusted Ventilatory Assist,(NAVA)is an FDA approved mode of ventilation that allows patients to breathe spontaneously in proportion to the normal electronic physiologic signal of the diaphragm. This feature offers the advantage of total breath cycle synchrony. Two small studies revealed a decreased peak airway pressure(PIP)for pediatric patients ventilating in the NAVA mode of ventilation in comparison to Pressure Support Ventilation,(PSV),(Breatnac,2010,Bengtsson 2010). The purpose of this study was to determine whether PIP would decrease in NAVA in comparison to pneumatically triggered, (primarily SIMV) modes of ventilation,and trend the physiological effect on parameters that contribute to minute ventilation. Method: A convenience sample of 15 patients in the Pediatric Intensive Care Unit,(PICU) was included in our pilot study. Blood gas data was collected from our electronic charting system. PIP and other ventilation parameters were downloaded from the Servo i ventilator utilizing an electronic data card. Data was continuously collected by minute from 30-minutes prior, and 6 hours after swiching to NAVA from conventional modes. Descriptive statistics were used to summarize the sample demographics and outcome measures. Mixed model repeated measures ANCOVA was conducted to test mean outcome differences among baseline(30 minutes before), 30 minutes after and 6 hours after NAVA accounting for age, gender, weight, pre-NAVA mode of ventilation and NAVA level. Post-hoc multiple comparison adjustment was applied for significant effect. Results: PatientsÂ’ ages ranged from three weeks to 15 years with a median of 1.25 years (IQR = 2.75). This sample was primarily male (66.7%) and their weight ranged from 3.6 to 77.2 kilograms (Median = 8.3, IQR = 8.7). PIP consistently and significantly decreased at both at 30 minutes and 6 hours after switching to NAVA (p = .0091). See Table 1 for effect for on tidal volume, minute ventilation, PH, and pCO2. Conclusion: This data supports the theory that improved breath cycle synchrony with the diaphragm may result in improved lung compliance. Data from our NAVA cohort revealed a consistent decrease in PIP after patients were switched to NAVA. All changes and variability in ventilation parameters were patient dependent. Overall decreases in tidal volume, increases in RR, and decreases in mean airway pressure were seen. Minute ventilation, pCO2 and PH were maintained in adequate ranges. Sponsored Research - None