Table 1 Patient characteristics and outcome parameters
Variables | Elastic power quartiles | P value | ||||
|---|---|---|---|---|---|---|
All (n = 403) | Q1 (n = 101) | Q2 (n = 100) | Q3 (n = 101) | Q4 (n = 101) | ||
≤ 13.2 | 13.2–16.5 | 16.5–22.5 | ≥ 22.5 | |||
Age (years) | 61 (47–75) | 67 (56–83) | 64 (51–76) | 58 (48–70) | 52 (41–65) | < 0.001 |
Gender (male), n (%) | 215 (53.3) | 48 (47.5) | 48 (48.0) | 60 (59.4) | 59 (58.4) | 0.168 |
BMI (kg/m2) | 27.8 (24.0–32.3) | 25.0 (22.5–29.3) | 28.8 (25.3–33.2) | 28.6 (24.4–34.5) | 28.2 (25.6–34.3) | < 0.001 |
PBW (kg) | 63.9 (54.7–72.2) | 61.0 (53.7–70.8) | 61.6 (54.8–70.8) | 66.3 (56.9–73.1) | 64.3 (57.1–73.1) | 0.045 |
SOFA score | 7 (5–10) | 6 (4–8) | 7 (5–9) | 7 (5–10) | 8 (5–12) | < 0.001 |
SAPS II | 45 (33–56) | 44 (35–55) | 45 (36–57) | 43 (31–55) | 46 (33–58) | 0.611 |
Causes of ARDS, n (%) | ||||||
Sepsis | 139 (34.5) | 24 (23.8) | 32 (32.0) | 40 (39.6) | 43 (42.6) | 0.023 |
Respiratory disease | 272 (67.5) | 64 (63.4) | 69 (69.0) | 65 (64.4) | 74 (73.3) | 0.411 |
Trauma | 20 (5.0) | 1 (1.0) | 2 (2.0) | 10 (9.9) | 7 (6.9) | 0.013 |
Others | 54 (13.4) | 20 (19.8) | 9 (9.0) | 18 (17.8) | 7 (6.9) | 0.014 |
Comorbidities, n (%) | ||||||
Coronary artery | 50 (12.4) | 21 (20.8) | 8 (8.0) | 11 (10.9) | 10 (9.9) | 0.028 |
COPD | 25 (6.2) | 8 (7.9) | 7 (7.0) | 4 (4.0) | 6 (5.9) | 0.681 |
Chronic liver | 5 (1.2) | 1 (1.0) | 0 (0) | 1 (1.0) | 3 (3.0) | 0.400 |
Chronic renal | 17 (4.2) | 2 (2.0) | 5 (5.0) | 0 (0) | 10 (9.9) | < 0.001 |
Diabetes | 95 (23.6) | 19 (18.8) | 32 (32.0) | 23 (22.8) | 21 (20.8) | 0.128 |
Stroke | 12 (3.0) | 3 (3.0) | 3 (3.0) | 3 (3.0) | 3 (3.0) | 1.000 |
Physiological variables in the first 24 h | ||||||
PH | 7.31 (7.22–7.38) | 7.32 (7.26–7.37) | 7.32 (7.23–7.37) | 7.30 (7.23–7.38) | 7.30 (7.22–7.36) | 0.311 |
PCO2 (mmHg) | 43.0 (37.0–53.0) | 42.0 (37.0–47.4) | 42.0 (37.8–51.0) | 43.0 (37.0–52.0) | 43.0 (38.4–54.0) | 0.364 |
Lowest PO2/FiO2 ratio (mmHg) | 120.0 (83.3–155.0) | 157.1 (113.9–185.0) | 124.5 (97.1–151.2) | 115.0 (79.0–138.3) | 86.2 (62.0–120.0) | < 0.001 |
Respiratory mechanics parameters in the second 24 h | ||||||
VT (ml/kg PBW) | 8.1 (7.0–9.2) | 8.0 (6.9–9.1) | 8.5 (7.6–9.7) | 7.9 (6.9–9.0) | 7.7 (6.5–8.9) | 0.003 |
PEEP (cmH2O) | 8.5 (5.0–12.0) | 5.0 (5.0–7.0) | 6.9 (5.0–9.0) | 10.0 (7.5–12.0) | 13.5 (10.0–16.2) | < 0.001 |
Pplat (cmH2O) | 22.8 (19.0–27.5) | 18.2 (16.5–20.5) | 21.8 (19.2–23.8) | 23.8 (21.5–27.2) | 29.8 (27.0–34.0) | < 0.001 |
ΔP (cmH2O) | 14.0 (11.5–17.2) | 12.5 (10.0–14.3) | 14.6 (12.0–16.6) | 13.5 (11.0–17.0) | 16.0 (13.5–19.8) | < 0.001 |
RR (bpm) | 22.0 (18.0–25.8) | 18.0 (15.8–20.2) | 20.9 (17.2–23.6) | 24.0 (20.0–26.0) | 26.5 (23.0–30.2) | < 0.001 |
Cst (ml/cmH2O) | 35.4 (28.2–45.4) | 41.1 (33.4–51.5) | 37.8 (30.3–51.3) | 38.9 (28.3–50.1) | 33.1 (26.0–39.7) | < 0.001 |
MP (J/min) | 22.6 (17.5–28.8) | 14.8 (12.4–17.4) | 19.8 (17.9–23.5) | 24.9 (21.6–27.5) | 32.3 (28.8–39.2) | < 0.001 |
EP (J/min) | 16.6 (13.2–22.5) | 11.1 (9.7–12.4) | 14.8 (13.9–15.8) | 19.2 (18.1–20.8) | 27.6 (24.0–30.6) | < 0.001 |
FiO2 (%) | 55 (45–71) | 45 (40–55) | 50 (45–55) | 60 (50–75) | 70 (55–80) | < 0.001 |
Clinical outcomes (days) | ||||||
IMV duration | 7.0 (4.2–12.5) | 5.9 (3.4–8.9) | 5.3 (3.6–9.6) | 7.2 (4.6–11.5) | 10.3 (5.9–16.6) | < 0.001 |
ICU LOS | 13.0 (8.0–21.5) | 10.0 (7.0–16.0) | 11.0 (8.0–19.2) | 13.0 (8.0–22.0) | 17.0 (12.0–27.0) | < 0.001 |
Hospital LOS | 20.0 (12.0–29.0) | 18.0 (11.0–26.0) | 17.0 (11.0–26.0) | 20.0 (12.0–31.0) | 21.0 (16.0–36.0) | 0.013 |