Table 1 Patient characteristics and clinical data
Parameter | All (N = 6282) | SvO2 ≥ 60% at admission + at 4 h (N = 4585) | SvO2 ≥ 60% at admission, < 60% at 4 h (N = 746) | SvO2 < 60% at admission, ≥ 60% at 4 h (N = 403) | SvO2 < 60% at admission + at 4 h (N = 528) | P |
|---|---|---|---|---|---|---|
Age (years), median (IQR) | 68 (60–74) | 67 (60–75) | 68 (61–74) | 70 (63–77) | 70 (63–77) | 0.052 |
Male sex, % (n) | 74.4 (4657) | 74.4 (3408) | 79.6 (594) | 68.5 (276) | 71.8 (379) | < 0.001 |
BMI (kg/m2), median (IQR) | 27.3 (24.5–30.4) | 27.1 (24.4–30.1) | 27.6 (24.7–30.5) | 27.7 (25.1–31.0) | 28.1 (25.3–31.3) | < 0.001 |
Preoperative conditions, % (n) | ||||||
Ejection fraction < 35%* | 5.0 (292) | 4.5 (194) | 4.6 (32) | 6.0 (22) | 9.1 (44) | < 0.001 |
Insulin-dependent diabetes | 15.0 (876) | 13.9 (595) | 15.1 (105) | 19.6 (72) | 21.5 (104) | < 0.001 |
Preoperative acute kidney injury | 7.4 (433) | 6.9 (275) | 10.0 (70) | 10.4 (38) | 10.3 (50) | < 0.001 |
Surgical information, % (n) | ||||||
Previous cardiac surgery | 4.9 (288) | 4.8 (205) | 4.2 (29) | 5.7 (21) | 6.8 (33) | 0.16 |
Emergency surgery | 4.8 (279) | 3.5 (148) | 5.0 (35) | 9.2 (34) | 12.8 (62) | < 0.001 |
CABG | 52.8 (3311) | 55.0 (2521) | 48.1 (359) | 54.1 (218) | 40.3 (213) | < 0.001 |
Valvular surgery | 29.1 (1825) | 30.0 (1372) | 29.0 (216) | 26.3 (106) | 24.8 (131) | < 0.001 |
Combined procedures | 12.1 (756) | 9.4 (431) | 17.4 (130) | 14.1 (57) | 26.1 (138) | < 0.001 |
Ascending aortic repair and aortic dissection | 3.5 (217) | 3.1 (141) | 4.2 (31) | 3.7 (15) | 5.7 (30) | < 0.001 |
Other cardiac surgery | 2.4 (153) | 2.6 (120) | 1.3 (31) | 1.7 87) | 3.0 (16) | < 0.001 |
ICU scores | ||||||
APACHE II on admission, median (IQR) | 14 (11–17) | 13 (11–16) | 15 (12–18) | 15 (12–18) | 16 (13–19) | < 0.001 |
APACHE II ≥ 25 on admission, % (n) | 3.0 (187) | 2.0 (91) | 3.8 (28) | 6.2 (25) | 8.1 (43) | < 0.001 |
SOFA on admission, median (IQR) | 6 (5–7) | 6 (5–7) | 7 (6–8) | 6 (5–8) | 7 (6–8) | < 0.001 |
SOFA ≥ 8 on admission, % (n) | 19.4 (1216) | 15.5 (712) | 26.1 (195) | 29.0 (117) | 36.4 (192) | < 0.001 |
SOFA max, median (IQR) | 6 (5–8) | 6 (5–7) | 7 (6–9) | 7 (6–9) | 8 (7–10) | < 0.001 |
ICU data | ||||||
Duration of mechanical ventilation (days), median (IQR) | 0.24 (0.17–0.42) | 0.22 (0.16–0.33) | 0.27 (0.17–0.57) | 0.29 (0.21–0.71) | 0.63 (0.26–1.8) | < 0.001 |
Renal replacement therapy needed, % (n) | 2.4 (149) | 1.3 (58) | 2.8 (21) | 4.7 (19) | 9.7 (51) | < 0.001 |
Max VIS category 0–24 h, % (n) | ||||||
0–5 | 16.7 (1047) | 19.2 (285) | 11.5 (86) | 13.4 (54) | 4.7 (528) | < 0.001 |
5–15 | 40.0 (2500) | 42.9 (1965) | 35.9 (268) | 34.4 (139) | 24.2 (128) | < 0.001 |
15–30 | 23.5 (1473) | 22.7 (1041) | 26.3 (196) | 24.8 (100) | 25.8 (136) | < 0.001 |
30–45 | 6.9 (433) | 6.2 (285) | 8.3 (62) | 7.4 (30) | 10.6 (56) | < 0.001 |
>45 | 12.9 (809) | 9.0 (412) | 18.0 (134) | 19.9 (80) | 34.7 (183) | < 0.001 |
Max weight gain (kg), median (IQR) | 4.5 (2.5–6.6) | 4.2 (2.3–6.0) | 5.4 (3.4–7.5) | 5.0 (3.0–7.8) | 6.0 (3.0–8.9) | < 0.001 |
First 24-h diuresis (mL), median (IQR) | 2290 (1865–2820) | 2300 (1890–2805) | 2300 (1850–2850) | 2300 (1850–2900) | 2300 (1750–3000) | 0.50 |
First 24-h fluids (mL), median (IQR) | 4500 (3800–5400) | 4450 (3800–5300) | 4600 (3900–5600) | 4500 (3700–5300) | 4500 (3900–5500) | 0.14 |
Total red blood cell transfusions (units), median (IQR) | 2 (1–4) | 2 (1–3) | 2 (1–4) | 2 (1–4) | 4 (2–5) | < 0.001 |
LOS ICU (days), median (IQR) | 1 (0.9–2.0) | 1 (0.9–1.9) | 1.8 (0.9–2.9) | 1.7 (0.9–3.6) | 2.8 (1.1–4.8) | < 0.001 |
LOS hospital (days), median (IQR) | 8 (7–11) | 8 (6–10) | 8 (7–12) | 8 (7–12) | 10 (8–15) | < 0.001 |
30-d mortality, % (n) | 2.1 (132) | 1.8 (54) | 2.6 (19) | 4.5 (18) | 7.8 (41) | < 0.001 |
1-year mortality, % (n) | 4.3 (267) | 3.0 (137) | 5.0 (37) | 7.7 (31) | 11.8 (62) | < 0.001 |