Preliminary study of ventilation with 4 ml/kg tidal volume in acute respiratory distress syndrome: feasibility and effects on cyclic recruitment - derecruitment and hyperinflation

Table 4 Analysis of density fractions of the lungs.

	Tidal volume
	Vt 4	Vt 6	P
Maximal non-aereated tissue	49 (27-76)	50 (26-76)	0.845
Maximal poorly aerated tissue	28 (15-44)	28 (15-45)	0.695
Maximal normally aerated tissue	24 (10-46)	25 (10-45)	0.275
Maximal hyperinflated tissue	0.6 (0.2-1.7)	0.7 (0.3-2.2)	0.013
Minimal non-aerated tissue	46 (24-73)	46 (21-73)	0.232
Minimal poorly aerated tissue	26 (14-42)	26 (14-39)	0.431
Minimal normally aerated tissue	22 (9-45)	22 (9-42)	0.431
Minimal hyperinflated tissue	0.2 (0.1-1.1)	0.2 (0.1-1.0)	0.128
Δ Non-aerated tissue	2.9 (0.9-4.7)	3.6 (2.5-5.7)	0.006
Δ Poorly aerated tissue	2.9 (1.0-4.4)	3.2 (0.4-6.1)	0.322
Δ Normally aerated tissue	1.6 (0.0-4.15)	2.1 (0.7-6.7)	0.131
Δ Hyperinflated tissue	0.3 (0.1-0.6)	0.5 (0.2-1.2)	0.002

Values in the table correspond to percentage of total lung slice weight and are expressed as median (minimal - maximal). All variables were compared by Wilcoxon signed rank test. Δ, difference between maximal and minimal values. Vt 4, tidal volume 4 ml/kg predicted body weight (PBW); Vt 6, tidal volume 6 ml/kg PBW.

ISSN: 1364-8535