Skip to main content
. Author manuscript; available in PMC: 2016 May 1.
Published in final edited form as: Crit Care Med. 2015 May;43(5):1026–1035. doi: 10.1097/CCM.0000000000000921

Table 1.

Patient characteristics

VD/VT Cohort ARDSNet
Cohort
(n = 3,135)

ALTA
(n = 92)
EPVent
(n = 57)
APC
(n = 61)
Total
(n = 210)
Demographics
Age 50 ± 17 54 ± 19 52 ± 18 52 ± 18 51 ± 16
Female 46 (50%) 22 (39%) 26 (43%) 94 (45%) 1,439 (46%)
Non-white race 28 (30%) 7 (12%) 18 (30%) 53 (25%) 871 (28%)
Body mass index (kg/m2) 29.0 ± 9.0 30.7 ± 9.3 28.3 ± 7.4 29.3 ± 8.7 28.7 ± 7.6
Clinical Characteristics
APACHE II 26 ± 7 26 ± 6 20 ± 7 25 ± 7 27 ± 7
Shock 59 (64%) 33 (58%) 16 (26%) 108 (51%) 1,733 (55%)
Primary cause of lung injury
  Aspiration or pneumonia 50 (54%) 8 (14%) 44 (72%) 102 (49%) 1,952 (62%)
  Sepsis 24 (26%) 14 (25%) 9 (15%) 47 (22%) 659 (21%)
  Multiple transfusions 2 (2%) 0 0 2 (1%) 65 (2%)
  Trauma 8 (9%) 15 (26%) 0 23 (11%) 223 (7%)
  Other 8 (9%) 20 (35%) 8 (13%) 36 (17%) 235 (8%)
Respiratory Characteristics
Tidal volume (mL) 390 ± 70 493 ± 96 415 ± 92 425 ± 94 408 ± 94
Tidal volume (mL/kg PBW) 6.3 ± 0.9 7.7 ± 1.4 6.7 ± 1.4 6.8 ± 1.3 6.5 ± 1.4
Respiratory rate (breaths/min) 28 ± 7 25 ± 6 27 ± 7 27 ± 7 27 ± 7
PEEP (cmH2O) 9 ± 3 13 ± 4 9 ± 3 10 ± 4 10 ± 4
PaO2/FiO2 184 ± 63 148 ± 57 160 ± 63 167 ± 63 172 ± 76
PaCO2 (mmHg) 40 ± 8 41 ± 8 41 ± 11 41 ± 9 41 ± 10
Respiratory system compliance (mL/cmH2O) 32 ± 17 36 ± 11 31 ± 22 33 ± 17 32 ± 17
Murray lung injury score 2.4 ± 0.6 2.8 ± 0.6 2.6 ± 0.6 2.6 ± 0.6 2.6 ± 0.7
VD/VT measured 0.57 ± 0.12 0.67 ± 0.10 0.59 ± 0.12 0.60 ± 0.12 N/A
Clinical Outcomes
Mortality 12 (13%) 15 (26%) 7 (11%) 34 (16%) 693 (22%)
Vent-free days through day 28 16 ± 10 10 ± 9 15 ± 10 14 ± 10 14 ± 11

Data are reported as mean ± standard deviation or number (%).

Abbreviations: PEEP = positive end-expiratory pressure; VD/VT = dead-space fraction.