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Table 3 Mechanical data at end a

From: Biphasic positive airway pressure minimizes biological impact on lung tissue in mild acute lung injury independent of etiology

  ALIp ALIexp
Parameters PCV BIVENT-100 BIVENT-75 BIVENT-50 PCV BIVENT-100 BIVENT-75 BIVENT-50
RR (breaths/min) C 99 (98 to 99) 23 (0 to 48)b 21 (0 to 45)b 20 (0 to 22)b 99 (79 to 99) 63 (30 to 64) 0 (0 to 0)b 8 (0 to 17)b
M 13 (0 to 29) 0 (0 to 31) 8 (4 to 14)c,d 0 (0 to 0) 54 (33 to 74) 33 (8 to 49)
Phigh 45 (18 to 48) 26 (0 to 72) 22 (11 to 22) 32 (7 to 34) 18 (0 to 39) 0 (0 to 16)
Plow 44 (41 to 44)c,d 0 (0 to 0) 0 (0 to 0) 21 (0 to 49)
Total 99 (98 to 99) 104 (96 to 129) 83 (74 to 105)b 72 (49 to 98) 99 (79 to 99) 97 (96 to 110) 73 (72 to 76) 92 (91 to 97)
Vt (ml) C 1.8 (1.7 to 1.9) 0.7 (0 to 1.7) 0.4 (0 to 1.2)b 0.6 (0 to 1.4) 1.7 (1.7 to 1.8) 0.7 (0.3 to 1.2)b 0 (0 to 0)b 0.3 (0 to 0.6)b
M 0.4 (0 to 2.0) 0 (0 to 1.4) 2.4 (2.2 to 3.2)c,d 0 (0 to 0) 2.3 (1.6 to 2.6)d 1.7 (1.4 to 2.2)
Phigh 2.0 (1.8 to 2.4) 1.7 (0 to 1.9) 2.2 (1.9 to 3.2) 2.2 (1.7 to 2.4) 1.17 (0.0 to 2.6) 0 (0 to 1.9)
Plow 1.9 (1.5 to 2.1)c,d 0 (0 to 0) 0 (0 to 0) 0.9 (0 to 1.9)
Total 1.8 (1.7 to 1.9) 1.4 (1.3 to 1.8) 2.3 (1.6 to 2.6) 1.6 (1.4 to 2.0) 1.7 (1.7 to 1.8) 1.5 (1.3 to 1.7) 1.7 (1.4 to 2.2) 1.8 (1.6 to 2.3)
V′e (ml/min) C 176 (164 to 185) 24 (0 to 38)b 15 (0 to 66)b 12 (0 to 41)b 168 (139 to 171) 34 (20 to 75) 0 (0 to 0)b 4 (0 to 10)b
M 11 (0 to 58) 0 (0 to 42) 19 (10 to 49)c 0 (0 to 0) 107 (85 to 178) 54 (22 to 78)
Phigh 98 (37 to 124) 42 (0 to 142) 48 (21 to 67) 78 (15 to 80) 42 (0 to 105) 0 (0 to 31)
Plow 0 (0 to 0) 0 (0 to 0) 79 (66 to 90)c,d 0 (0 to 0) 0 (0 to 0) 43 (0 to 91)
Total 176 (164 to 185) 168 (152 to 194) 125 (101 to 158) 156 (147 to 214) 168 (139 to 171) 154 (147 to 165) 190 (118 to 263) 115 (78 to 171)
Ppeak,aw (cmH2O) C 13.6 (13.2 to 15.1) 10.6 (8.8 to 13.5) 11.3 (10.9 to 13.1) 11.1 (9.6 to 11.6) 13.5 (13.1 to 13.5) 9.3 (9.2 to 11.8) 13.7 (13.7 to 13.7) 9.3 (8.2 to 10.5)
M 12.9 (10.6 to 14.3) 12.9 (12.1 to 13.6) 11.5 (10.8 to 12.2) 10.7 (10.7 to 10.7) 9.3 (8.3 to 12.0) 11.0 (10.2 to 12.6)
Pmean,aw (cmH2O) C 9.0 (8.8 to 9.6) 7.8 (7.1 to 9.5) 7.5 (7.4 to 8.2) 8.3 (7.7 to 8.4) 8.8 (8.7 to 9.0) 8.2 (7.2 to 10.2) 8.6 (8.6 to 8.6) 8.0 (7.0 to 13.4)
M 8.6 (7.0 to 9.4) 7.9 (7.4 to 8.3) 7.1 (6.4 to 7.4) 7.3 (7.3 to 7.3) 6.0 (5.5 to 7.2) 6.7 (6.5 to 6.8)
Ti/Ttot (s) C 0.36 (0.35 to 0.37) 0.48 (0 to 0.58) 0.18 (0 to 0.38) 0.46 (0 to 0.47) 0.35 (0.35 to 0.37) 0.50 (0.47 to 0.51) 0 (0 to 0)d 0.24 (0 to 0.58)
PEEP (cmH2O) 5.0 5.0 5.0 5.0 5.0 5.0 5.0 5.0
PTP (cmH2O/ml) M 49.9 (0 to 138.3) 0 (0 to 8.3) 37.0 (74.2 to 14.1)c 0 (0 to 0) 42.3 (30.4 to 103.4)d 12.1 (0 to 17.0)
Phigh 152.7 (19.4 to 321.6) 46.2 (0 to 128.6) 45.4 (5.2 to 66.2)d 50.3 (16.6 to 101.2) 11.3 (0 to 34.1) 0 (0 to 14.9)d
Plow 0 (0 to 0) 0 (0 to 0) 174.4 (89.0 to 251.6)c,d 0 (0 to 0) 0 (0 to 0) 25.5 (0 to 99.3)c,d
Total 254.7 (171.1 to 372.2) 96.0 (29.1 to 217.8) 274.0 (152.8 to 323.8) 78.3 (45.3 to 123.9) 78.3 (44.0 to 122.5) 60.6 (10.5 to 99.3)c,d
P0.1 (cmH2O) M 0.2 (0 to 0.9) 0 (0 to 0.1) 1.1 (0.9 to 1.3)c,d 0 (0 to 0) 1.0 (0.6 to 1.3)d 0.2 (0 to 0.8)
Phigh 0.5 (0.2 to 1.5) 0.5 (0 to 1.1) 0.7 (0.3 to 1.0) 2.2 (1.3 to 2.8) 0.3 (0 to 1.0) 0 (0 to 0.9)
  Plow 0 (0 to 0) 0 (0 to 0) 1.3 (0.6 to 1.5)c,d 0 (0 to 0) 0 (0 to 0) 0.5 (0 to 2.0)c,d
  1. aALIexp: extrapulmonary acute lung injury; ALIp: pulmonary acute lung injury; BIVENT: biphasic positive airway pressure at different rates of time-cycled controlled breaths: 100, 75 and 50 breaths/min; C = fully controlled breaths; M = mixed, assisted breaths; P0.1: driving pressure; PCV: pressure-controlled ventilation; PEEP: positive end-expiratory pressure; Phigh = spontaneous breaths at high continuous positive airway pressure; Plow = spontaneous breaths at low continuous positive airway pressure; Pmean,aw: mean airway pressure; Ppeak,aw: peak airway pressure; PTP: pressure–time product per breath; RR: respiratory rate; V′e: minutes on ventilation; Vt: tidal volume; Ti/Ttot: inspiratory time divided by total respiratory cycle time. Values are medians and IQRs of six rats per group. bPCV, cBIVENT-75, dBIVENT-100 (P < 0.05).