Neurally adjusted ventilatory assist

Neurally adjusted ventilatory assist

NAVA - Neurally Adjusted Ventilatory Assist - is a mode of mechanical ventilation. NAVA delivers assist in proportion to and in synchrony with the patient's respiratory efforts, as reflected by the Edi signal. This signal represents the electrical activity of the diaphragm, the body's principal breathing muscle[1].

The act of taking a breath is controlled by the respiratory center of the brain, which decides the characteristics of each breath, timing and size. The respiratory center sends a signal along the phrenic nerve, excites the diaphragm muscle cells, leading to muscle contraction and descent of the diaphragm dome. As a result, the pressure in the airway drops, causing an inflow of air into the lungs[2].

With NAVA, the electrical activity of the diaphragm (Edi) is captured, fed to the ventilator and used to assist the patient's breathing in synchrony with and in proportion to the patients own efforts, regardless of patient category or size. As the work of the ventilator and the diaphragm is controlled by the same signal, coupling between the diaphragm and the SERVO-i ventilator is synchronized simultaneously[3] [4] [5] [6] [7] [8] [9] [10] [11].


  1. ^ MacIntyre N (February 2010). "Talk to me! Toward better patient-ventilator communication". Critical Care Medicine 38 (2): 714–5. doi:10.1097/CCM.0b013e3181c0ddef. PMID 20083941. 
  2. ^ Brochard LJ (November 2009). "Tidal volume during acute lung injury: let the patient choose?". Intensive Care Medicine 35 (11): 1830–2. doi:10.1007/s00134-009-1632-z. PMID 19760207. 
  3. ^ MAQUET, NAVA, brochure, 2010 MAQUET Critical Care AB, Order No MX-0616
  4. ^ Navalesi P, Colombo D, Della Corte F (May 2010). "NAVA ventilation". Minerva Anestesiologica 76 (5): 346–52. PMID 20395897. 
  5. ^ Schmidt M, Demoule A, Cracco C, et al. (March 2010). "Neurally adjusted ventilatory assist increases respiratory variability and complexity in acute respiratory failure". Anesthesiology 112 (3): 670–81. doi:10.1097/ALN.0b013e3181cea375. PMID 20179505. 
  6. ^ Spahija J, de Marchie M, Albert M, et al. (February 2010). "Patient-ventilator interaction during pressure support ventilation and neurally adjusted ventilatory assist". Critical Care Medicine 38 (2): 518–26. doi:10.1097/CCM.0b013e3181cb0d7b. PMID 20083921. 
  7. ^ Saddy F, Thompson A, Gago F, et al. (April 2009). "Comparison of energy expenditure between neurally adjusted ventilatory assist and pressure support ventilation in COPD patients". American Journal of Respiratory and Critical Care Medicine 179 (1): A3817. 
  8. ^ Conti G, Costa R (February 2010). "Technological development in mechanical ventilation". Current Opinion in Critical Care 16 (1): 26–33. doi:10.1097/MCC.0b013e328334b1e3. PMID 19956072. 
  9. ^ Wu XY, Huang YZ, Yang Y, Liu SQ, Liu HG, Qiu HB (July 2009). "[Effects of neurally adjusted ventilatory assist on patient-ventilator synchrony in patients with acute respiratory distress syndrome]" (in Chinese). Zhonghua Jie He He Hu Xi Za Zhi 32 (7): 508–12. PMID 19954004. 
  10. ^ Del Sorbo L, Slutsky AS (February 2010). "Ventilatory support for acute respiratory failure: new and ongoing pathophysiological, diagnostic and therapeutic developments". Current Opinion in Critical Care 16 (1): 1–7. doi:10.1097/MCC.0b013e32833500bc. PMID 19952735. 
  11. ^ Campoccia Jalde F, Almadhoob AR, Beck J, Slutsky AS, Dunn MS, Sinderby C (2010). "Neurally adjusted ventilatory assist and pressure support ventilation in small species and the impact of instrumental dead space". Neonatology 97 (3): 279–85. doi:10.1159/000255167. PMID 19887857.