Table 1. Characteristics of study cohort.
| Characteristics | All patients | Rescue Therapy | No Rescue Therapy | P valuea |
|---|---|---|---|---|
| N (%) | 428 (100) | 62 (14) | 366 (86) | -- |
| Propensity score, mean (SD) | -- | 0.28 (0.18) | 0.12 (0.11) | < 0.01 |
| Age, y, mean (SD) | 51. 0 (17.7) | 41.7 (19.0) | 52.6 (17.0) | < 0.01 |
| Male gender, n (%) | 310 (72) | 42 (68) | 268 (73) | 0.36 |
| Body mass index, mean (SD) | 29.5 (8.7) | 30.1 (10.7) | 29.4 (8.3) | 0.54 |
| Race/Ethnicity, n (%) | 0.01 | |||
| Caucasian | 296 (69) | 36 (58) | 260 (71) | |
| African American | 40 (9) | 5 (8) | 35 (9) | |
| Asian | 46 (11) | 7 (11) | 39 (11) | |
| Hispanic | 15 (4) | 8 (13) | 7 (2) | |
| Native American | 22 (5) | 4 (7) | 18 (5) | |
| Unknown | 9 (2) | 2 (3) | 7 (2) | |
| Patient population, n (%) | 0.57 | |||
| Medical | 363 (85) | 55 (89) | 308 (84) | |
| Trauma | 27 (6) | 4 (6) | 23 (6) | |
| Surgical, non-trauma | 38 (9) | 3 (5) | 35 (10) | |
| Primary admission diagnostic category, n (%) | < 0.01 | |||
| Sepsis or Pneumonia | 141 (33) | 32 (52) | 109 (30) | |
| Trauma | 113 (26) | 10 (16) | 103 (28) | |
| Neurological injury | 42 (10) | 9 (14) | 33 (9) | |
| Other | 132 (31) | 11 (18) | 121 (33) | |
| Mechanically ventilated within 24 hours of ICU admit, n (%) | 163 (38) | 33 (53) | 130 (36) | 0.01 |
| SAPS II, mean (SD) | 60.8 (18) | 60.8 (17.1) | 60.8 (18.3) | 0.99 |
| ISS in trauma patients, mean (SD) (n=169) | 32.1 (15.8) | 35.0 (14.7) | 31.7 (16.0) | 0.36 |
| AIS – Head, mean (SD) (n=102) | 3.44 (1.29) | 3.9 (1.3) | 3.4 (1.3) | 0.15 |
| AIS – Chest, mean (SD) (n=113) | 3.77 (0.76) | 3.9 (0.74) | 3.8 (0.77) | 0.64 |
| PaO2/FIO2 ratio at ICU admission, mean (SD) | 160 (108) | 150 (127) | 162 (104) | 0.47 |
| Study qualifying PaO2/FIO2 ratio, mean (SD)b | 76 (16) | 68 (18) | 78 (16) | < 0.01 |
| ICU length of stay (days), median (IQR) | 15 (8, 25) | 17 (6, 31) | 14 (8, 24) | 0.47 |
| Hospital length of stay (days), median (IQR) | 20 (10, 34) | 21 (8, 36) | 20 (10, 34) | 0.94 |
| Hospital costs, mean (SD)c | 189K (172K) | 218K (193K) | 184K (168K) | 0.20 |
SD: standard deviation; SAPS II: simplified acute physiology score II; ISS: injury severity score; AIS: abbreviated injury severity; ISS and AIS applicable only for trauma patients
a
Two-sample t-test with assumption of unequal variance or Fisher's exact test, comparing Rescue Therapy versus No Rescue Therapy
b
Value of first PaO2/FIO2 ratio <100 within 72 hours of admission to ICU
c
Mean hospital costs, adjusted for inflation and reported in 2012 U.S. Dollars.