The Science Journal of the American Association for Respiratory Care

2012 OPEN FORUM Abstracts


Jerrold Judd2,1, Jonathan Kaufman1, Eduardo Da Cruz1; 1Cardiac Intensive Care Unit, The Heart Institute, Department of Pediatrics, Children’s Hospital Colorado, Aurora, CO; 2Respiratory Care, Children’s Hospital Colorado, Aurora, CO

Background: Neurally adjusted ventilatory assist (NAVA) is a mode of ventilation that senses the electrical activity of the diaphragm (Edi) through the use of an esophageal catheter with electrodes, and provides proportionally assisted support to a patient’s spontaneous breaths. Published studies have shown that its use can improve patient-ventilator synchrony and reduce mean airway pressure (MAP) and peak inspiratory pressure (PIP) during mechanical ventilation. OBJECTIVE: To evaluate the use of NAVA in a pediatric cardiac post-operative population in terms of patient-ventilator synchrony, MAP, PIP and oxygen requirements. METHODS: Fifteen children with congenital and acquired heart disease were assessed post-operatively. Patients were converted from conventional mechanical ventilation (CMV) to NAVA when appropriate strength of signal was being received by the Edi catheter (average of 10 microvolts per breath). The NAVA support level was set initially between 0.5 and 2.0cmH2O/uV to achieve a tidal volume of 5 to 6ml/kg body weight. We evaluated work of breathing, defined as subcostal or suprasternal retractions, oxygen saturation, tidal and minute volume, MAP, PIP and Edi for a period of two hours before and after transitioning to NAVA. RESULTS: In all patients, MAP was reduced by an average of 11% and PIP was reduced by an average of 28% in NAVA as compared to CMV. For one patient recovering after a Bi-Directional Glenn operation the MAP and PIP were reduced by an average of 27% and 47% respectively. Oxygen saturation improved on NAVA from 73% to 75% whilst the need for Nitric Oxide decreased from 40 to 10 ppm after four hours on NAVA. It was noted that in NAVA mode there is significant variability in tidal volumes due to the fact that each breath is delivered proportionately to the patient’s demand. CONCLUSION: In pediatric cardiac patients NAVA improved patient-ventilator synchrony, reduced MAP and PIP, and decreased oxygen requirement. This observation reveals a physiological benefit of NAVA in patients in whom cardiopulmonary interactions may be affected by increased MAP/PIP. Such potential benefits seen in this limited experience would call for further and larger prospective studies in this specific population. Sponsored Research - None