Table 2

Breathing pattern and transcutaneous blood gas tensions with spontaneous breathing, PSV and PAV

SBPSVSBPAVPSV – PAV
Values are mean (SD).
SB = spontaneous breathing; PSV = pressure support ventilation; PAV = proportional assist ventilation; V`e = minute ventilation; Vt = tidal volume; Ti = inspiratory time; Te = expiratory time; Ttot = total cycle duration; IC = inspiratory capacity; Tcco2 = transcutaneous CO2; Tco2 = transcutaneous O2; Sao2 = transcutaneous oxygen saturation; PSV − PAV = difference between PSV and PAV.
V`e (l/m)10.5 (2.3)13.9 (3.8)*10.1 (2.7)12.6 (4.0)*+1.34 (1.51)
Vt (l)0.5 (0.1)0.7 (0.2)*0.5 (0.2)0.7 (0.2)*+0.1 (0.1)
Ti (s)1.1 (0.3)1.1 (0.2)1.1 (0.2)1.1 (0.3)+0.0 (0.2)
Te (s)1.9 (0.6)2.0 (0.7)2.0 (0.6)2.3 (0.9)−0.2 (0.7)
Ttot (s)3.1 (0.9)3.1 (0.9)3.2 (0.8)3.4 (1.1)+0.2 (0.7)
IC (l)1.2 (0.3)1.1 (0.3)1.2 (0.3)1.2 (0.3)−0.1 (0.2)
Tcco2 (mm Hg)52 (6.1))48 (6.2)*52 (6.8)49 (5.1)*−1 (2.8)
Tco2 (mm Hg)62 (7.8)63 (8.0)61 (8.6)65 (7.4)−1 (6.7)
Sao2 (%)90 (3.5)93 (1.8)*91 (2.4)92 (2.4)1 (2.1)