Neurally Adjusted Ventilatory Assist (NAVA) is a unique approach to mechanical ventilation based on neural respiratory output.

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 patient’s 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 virtually simultaneously.

NAVA is available for both invasive and non-invasive ventilation (NIV), assuring effective patient-ventilator synchrony independent of patient interface.

NAVA is used in intensive care units in countries all around the world for neonatal, pediatric and adult patients.  Clinical evidence for NAVA has been documented in multiple clinical studies in scientific peer-reviewed journals, a body of work that continues to grow exponentially every year.

Always in synchrony: In NAVA, the ventilator delivers assist in proportion to patient demand, and the patient and ventilator are always in synchrony. This benefits the patient, as the synchronized respiratory assist enables lower assist levels, and eliminates the mismatch in pneumatic timing of inspiration and expiration, avoiding the risk of missed efforts. NAVA provides a smooth transition to natural breathing.

Edi – the respiratory vital sign: The Edi signal can be used as a diagnostic tool to monitor the electrical activity of the diaphragm (Edi) in any situation or ventilation mode as well as in standby after extubation. This provides useful information on respiratory drive, volume requirements and the effect of the ventilatory settings.

Decision support for intubation or extubation: The Edi signal also indicates patient condition. An increasing Edi may signify increasing weakness or worsening of the patient condition, as objective criteria for intubation decisions. As the patient’s condition improves, the decreasing Edi amplitude and pressure drop is an indicator to consider weaning and extubation.

Decision support for unloading and assist titration: The Edi signal enables clinicians to set the assist level from the ventilator and to optimize unloading. PEEP titrated to the lowest Edi means that work of breathing is minimized.  As the patient’s condition improves with NAVA, Edi amplitude decreases, resulting in a reduction in ventilator-delivered pressure.

Patient comfort: With NAVA, the respiratory muscles and the ventilator are driven by the same signal. This synchrony between patient and ventilator may minimize patient discomfort and agitation, promoting spontaneous breathing, providing for improved sleep quality and possibly reduced sedation.

Decreasing the patient’s pressure load and risk of over assist: The use of NAVA helps avoid over- or under assistance of the patient. In an increasing number of clinical studies, NAVA has been associated with lower levels of peak airway pressures, compared to conventional mechanical ventilation with Pressure Support.

In neonatal and pediatric intensive care patient populations, ventilation with NAVA was associated with improved patient-ventilator synchrony and lower peak airway pressure when compared with Pressure Support ventilation.

In conventional NIV, leaking around the mask is a major contributor to asynchrony between patient and ventilator. This can lead to patient discomfort, under-assist and other complications. For infants and neonates, conventional NIV can also be complicated by the inability of the ventilator’s pressure and flow triggers to reliably detect the infant’s weak effort to breathe.

NIV NAVA is neurally controlled: the assist is matched to neural demands and is delivered regardless of leakage associated with the patient interfaces. Breath triggering and cycle off are not affected by leakage, and every patient effort - independent of type of interface - is assessed and responded to equally effectively for all patients from adult to the smallest neonates.

The magazine Critical Care News and its website www.criticalcarenews.com is a forum hosted by MAQUET Critical Care for intensive care clinicians to share clinical experience of NAVA. The website is a primary source of user information about NAVA and NIV NAVA, and contains up-to-date lists of clinical literature reference lists, neonatal, pediatric and adult patient case reports as well as numerous NAVA lectures and interviews with intensive care physicians about NAVA.