Table 1 Baseline characteristics of the study cohort, stratified by hydration level according to bioelectrical impedance vector analysis measurement upon admission

Age, yr

63 (48–72)

66 (56–76)

61 (43–68)

65 (52–75)

0.43

Female sex, n (%)

23 (38 %)

5 (38 %)

11 (50 %)

7 (28 %)

0.30

Height, cm

168 (158–175)

168 (160–170)

169 (158–175)

173 (159–178)

0.77

Weight, kg

76 (67–96)

75 (64–85)

74 (67–88)

90 (72–109)

0.16

Body mass index, kg/m²

28 (24–33)

26 (24–29)

27 (23–30)

29 (25–36)

0.22

APACHE III score

62 (47–82)

75 (49–82)

53 (45–67)

72 (48–92)

0.21

Time from ICU admission until enrolled, h

14 (7–19)

11 (5–19)

11 (4–19)

15 (12–19)

0.23

Comorbidity

 Cardiovascular, n (%)

26 (43 %)

4 (29 %)

11 (50 %)

11 (44 %)

0.51

 COPD/asthma, n (%)

8 (13 %)

5 (38 %)

0 (0)

3 (12 %)

0.007

 Diabetes mellitus, n (%)

16 (26 %)

1 (7 %)

5 (23 %)

10 (40 %)

0.08

 Chronic liver disease, n (%)

8 (13 %)

1 (7 %)

0 (0)

7 (28 %)

0.009

 Neurological, n (%)

3 (5 %)

1 (7 %)

1 (5 %)

1 (4 %)

1.0

 Chronic kidney disease, n (%)

4 (7 %)

1 (7 %)

0 (0)

3 (12 %)

0.27

 Malignancy, n (%)

9 (15 %)

3 (21 %)

3 (14 %)

3 (12 %)

0.74

Non-operative admission diagnosis

 Sepsis, n (%)

10 (16 %)

4 (29 %)

4 (18 %)

2 (8 %)

0.24

 Cardiac, n (%)

8 (13 %)

4 (29 %)

2 (9 %)

2 (8 %)

0.21

 Neurological, n (%)

9 (15 %)

1 (7 %)

5 (23 %)

3 (12 %)

0.47

 Respiratory, n (%)

9 (15 %)

3 (21 %)

6 (27 %)

0 (0)

0.01

 Intoxication, n (%)

2 (3 %)

0 (0)

1 (5 %)

1 (4 %)

1.0

 Liver, n (%)

2 (3 %)

0 (0)

0 (0)

2 (8 %)

0.34

 Gastrointestinal, n (%)

5 (8 %)

0 (0)

0 (0)

5 (20 %)

0.02

Operative admission diagnosis

 Neurological, n (%)

3 (5 %)

1 (7 %)

0 (0)

2 (8 %)

0.44

 Vascular, n (%)

2 (3 %)

0 (0)

1 (5 %)

1 (4 %)

1.0

 Gastrointestinal, n (%)

11 (18 %)

1 (7 %)

3 (14 %)

7 (28 %)

0.27