Physiological effects of invasive ventilation with neurally adjusted ventilatory assist (NAVA) in a crossover study

Table 2 Respiratory parameters, hemodynamics and biological data

Respiratory parameters	CV	NAVA	NAVA versus CV	P
Respiratory rate (/min)	30 (7)	35 (13)	+26.4 (-3.6, +56.4)	0.17
V_T (ml/kg)	6.6 (0.7)	6.9 (0.3)	+5.3 (-5.5, +16.1)	0.46
Minute volume (L/min)	1.7 (0.4)	1.6 (0.6)	+5.4 (-4.3, +15.1)	0.67
PIP (cm H₂O)	21 (6)	11 (4)	-32.7 (-48.2, -17.1)	0.04
PEEP (cm H₂O)	4 (2)	4 (2)	-	(a)
EAdi max (microVolt)	3.9 (3.8)	6.3 (1.4)	+61.2 (-4.6, +126.9)	0.34
SpO₂ (%)	98 (3)	96 (3)	-1.2 (-2.8, +0.5)	0.14
FiO₂	30 (4)	30 (4)	-	(a)
Crs (ml/kg.cm H₂O)	0.37 (0.19)	0.87 (0.32)	+98.4 (+43.8, +153.0)	0.04
Hemodynamic parameters
Heart rate	156 (15)	156 (22)	+2.1 (-0.7, +4.5)	0.17
Systolic arterial pressure (mmHg)	93 (6)	99 (13)	+8.4 (+3.3, +13.6)	0.03
Diastolic arterial pressure (mmHg)	54 (12)	57 (6)	+3.6 (-3.0, +10.1)	0.46
Central venous pressure (mmHg)	11 (5)	10 (5)	+3.9 (-5.3, +13.1)	0.92
Cerebral NIRS (%)	62 (5)	61 (3)	+1.6 (-2.6, +5.8)	0.34
Cardiac index (L/min.m²)	2.33 (0.84)	2.26 (0.70)	+1.4 (-3.4, +6.2)	0.17
Pulse oximeter perfusion index (%)	1.50 (2.45)	1.78 (2.29)	+18.8 (+3.0, +34.7)	0.04
Venous blood gases
pH	7.32 (0.04)	7.32 (0.02)	-0.1 (-0.4, +0.2)	0.34
PCO₂ (mm Hg)	47.3 (5.1)	45.8 (8.1)	+0.6 (-5.1, +6.3)	0.50
ScvO₂ (%)	60.1 (20.9)	58.4 (15.4)	+3.3 (-5.7, +12.2)	0.60

Measurements in NAVA and CV are reported as median (interquartile). Variations between NAVA versus CV are reported as mean percentage (95 % CI). Statistical analyses between NAVA versus CV were performed by a Wilcoxon test for paired samples
(a) No changes in PEEP, FiO₂, neither in sedation or inotropic doses were allowed during these study periods
NAVA Neurally adjusted Ventilatory Assist, CV Conventional Ventilation, V_T tidal volume, PIP peak inspiratory pressure, Crs respiratory system compliance, EAdi electrical activity of the diaphragm, ScvO₂ central venous oxygen saturation

ISSN: 1471-2431