Review
Clinical review: Update on neurally adjusted ventilatory assist - report of a round-table conference
1 INSERM U1075, Caen F-14000, France
2 Université de Caen, Caen F-14000, France
3 CHRU Caen, Service de Réanimation Médicale, Caen F-14000, France
4 Adult Intensive Care and Burn Unit, Lausanne University Hospital (CHUV), Rue du Bugnon 46, 1011 Lausanne, Switzerland
5 Department of Anaesthesiology and Intensive Care 2, Bordeaux University Hospital, F-33000 Bordeaux, France
6 LUNAM Université, Angers, France Université Angers, CHU Angers, Medical ICU, 4 rue Larrey, 49933 Angers, Cedex 09 France
7 University Angers, CHU Angers, Réanimation Médicale, 49933 Angers, France
8 Centre d'Investigation Clinique - Innovations Technologiques, Services de Physiologie - Explorations Fonctionnelles, Hôpital Raymond Poincaré, AP-HP, E.A. 4497, Université de Versailles - Saint Quentin en Yvelines, 92380 Garches, France
9 INSERM U955, 94000 Créteil, France
10 Hôpital du Sacré-Coeur de Montréal, 5400 boul. Gouin Ouest Montréal, Québec, H4J 1C5, Canada
11 Intensive Care Unit, Clinique Notre Dame de Grâce, Gosselies Hospital, 212 Chaussée de Nivelles, B-6041-Gosselies, Belgium
12 Intensive Care Unit, University Hospital St-Luc, 10 avenue Hippocrate, 1200 Brussels, Belgium
13 Medical Intensive Care Unit and Respiratory Division, Groupe Hospitalier Pitié-Salpêtrière, Université Pierrer et Marie Curie and INSERM974, Paris, France
14 Department of Critical Care Medicine and Anesthesiology (DAR B), Saint Eloi University Hospital and Universite of Montpellier, INSERM U1046, 80 Avenue Augustin Fliche, 34295 Montpellier, France
15 Intensive Care Unit, Hospital de Sant Pau C. St Quinti 89, 08041 Barcelona, Spain
16 Intensive Care Unit, Geneva University Hospital, School of Medicine, University of Geneva, Rue Gabrielle-Perret-Gentil 4, 1205 Geneva, Switzerland
17 Medical Intensive Care Unit, University Hospital, Charles Nicolle, 76000 Rouen, France
18 UPRES EA3830, Rouen, France
Critical Care 2012, 16:225 doi:10.1186/cc11297
Published: 20 June 2012Abstract
Conventional mechanical ventilators rely on pneumatic pressure and flow sensors and controllers to detect breaths. New modes of mechanical ventilation have been developed to better match the assistance delivered by the ventilator to the patient's needs. Among these modes, neurally adjusted ventilatory assist (NAVA) delivers a pressure that is directly proportional to the integral of the electrical activity of the diaphragm recorded continuously through an esophageal probe. In clinical settings, NAVA has been chiefly compared with pressure-support ventilation, one of the most popular modes used during the weaning phase, which delivers a constant pressure from breath to breath. Comparisons with proportional-assist ventilation, which has numerous similarities, are lacking. Because of the constant level of assistance, pressure-support ventilation reduces the natural variability of the breathing pattern and can be associated with asynchrony and/or overinflation. The ability of NAVA to circumvent these limitations has been addressed in clinical studies and is discussed in this report. Although the underlying concept is fascinating, several important questions regarding the clinical applications of NAVA remain unanswered. Among these questions, determining the optimal NAVA settings according to the patient's ventilatory needs and/or acceptable level of work of breathing is a key issue. In this report, based on an investigator-initiated round table, we review the most recent literature on this topic and discuss the theoretical advantages and disadvantages of NAVA compared with other modes, as well as the risks and limitations of NAVA.
