Table 1 Basic characteristics and outcomes of patients before and after matching

Age (years), median [IQR]

71.5 [59.5–77.3]

70.5 [57–77]

72 [61.3–79.5]

0.085

- -0.13

71 [76–77]

73 [61–81]

0.451

0.10

Male, n (%)

52 (54.7)

17 (53.1)

33 (52.4)

0.831

-0.04

17 (53.1)

15 (48.4)

0.800

0.09

BMI, median [IQR]

23.1 [20.4–27.1]

22.5 [20.6–26.7]

23.2 [19.9–27.2]

0.093

-0.02

22.7 [20.5–27.1]

22.3 [19.6–25.3]

0.464

-0.09

Reasons for ICU admission

 Respiratory failure, n (%)

34 (35.8)

15 (46.9)

19 (14.3)

0.119

0.35

14 (45.1)

13 (41.9)

1.000

0.07

 Sepsis, n (%)

22 (23.2)

8 (25.0)

14 (22.2)

0.800

0.07

7 (22.6)

7 (22.6)

1.000

0.07

 Circulatory failure, n (%)

12 (12.6)

4 (12.5)

8 (12.7)

0.800

-0.01

4 (12.9)

4 (12.9)

1.000

0.05

 Cerebrovascular disease, n (%)

15 (15.8)

3 (9.3)

12 (19.0)

0.150

-0.37

3 (9.3)

5 (16.1)

0.707

-0.27

 Acute pancreatitis, n (%)

5 (5.3)

4 (12.5)

1 (1.6)

0.043

0.49

4 (12.5)

1 (3.2)

0.354

0.5

 Acute kidney injury, n (%)

3 (3.2)

2 (6.3)

1 (1.6)

0.262

0.27

2 (6.4)

1 (3.2)

1.000

0.15

 Endocrine disease, n (%)

2 (2.1)

1 (3.1)

1(1.6)

1.000

0.11

1 (3.2)

0(0.0)

0.492

0.25

 Metabolic disorder, n (%)

2 (2.1)

1 (3.1)

1 (1.6)

1.000

0.11

1 (3.2)

0 (0.0)

0.492

0.01

Past medical history

 Alcohol dependence, n (%)

1 (0.01)

0 (0)

1 (0.02)

1.000

-

0 (0)

0 (0)

1.000

-

 Cognitive dysfunction, n (%)

7 (7.4)

0 (0)

7 (11.1)

0.09

-

0 (0)

0 (0)

1.000

-

APACHE II at ICU admission, median [IQR]

17 [13–22]

17 [13–24]

17 [13–22]

0.309

0.27

18 [14–25]

17 [5–10]

0.938

0.07

SOFA at ICU admission, median [IQR]

7 [5–9]

7 [5–10]

7 [4–9]

0.944

0.16

7 [5–10]

7 [4–12]

0.972

0.06

ICU length of stay (days), median [IQR]

6 [4–10]

8.5 [6–11.8]

6.5 [3–12]

0.041

0.58

8.5 [6–12]

7 [4–12]

0.203

0.15

ICU mortality, n (%)

8 (8.4)

3 (9.4)

5 (7.9)

0.831

0.05

3 (9.7)

2 (6.5)

1.000

0.1

28-day mortality, n (%)

19 (20.0)

5 (15.6)

14 (22.2)

0.590

-0.16

5 (15.6)

7 (22.6)

0.749

-0.1

Prone position, n (%)

7 (7.4)

5 (15.6)

2 (3.2)

0.041

0.48

5 (16.1)

1 (3.2)

0.195

0.31

Tracheotomy, n (%)

22 (23.2)

6 (18.8)

5 (20.0)

0.609

0.34

6 (19.4)

7 (22.6)

1.000

0.12

CRRT, n (%)

27 (28.4)

12 (37.5)

15 (23.8)

0.228

0.30

11 (35.5)

8 (25.8)

0.416

0.10

Drug use and dose

 Remifentanil

Use of remifentanil, n (%)

32 (33.7)

-

-

-

-

31 (100)

-

-

-

Infusion total dose (ug)

965 [491–2652]

-

-

-

-

981[474–2700]

-

-

-

Dosing duration (h)

73 [47–149]

-

-

-

-

78 [49–158]

-

-

-

Infusion rate-mean (ug/kg/min)

0.029 [0.02–0.06]

-

-

-

-

0.029 [0.02–0.06]

-

-

-

Fentanyl

Use of fentanyl, n (%)

88 (92.6)

20 (62.5)

63 (100.0)

< .001

-

20 (64.5)

31 (100)

< .001

-

Infusion total dose (ug)

829 [533–2235]

766 [101.7–947.9]

1523 [520–2780]

< .001

-

765 [101.9–992.1]

1678 [926–3620]

< .001

-

Dosing duration (h)

90 [41–163]

90 [42–209]

92 [45–178]

0.698

-

90 [42–207]

100 [48–192]

0.188

Infusion rate-mean (ug/kg/h)

0.16[0.14–0.20]

0.15 [0.14–0.19]

0.17 [0.14–0.20]

0.265

-

0.15 [0.14–0.19)

0.17 [0.15–0.19]

0.597

Use of noradrenaline, n (%)

56 (58.9)

21 (65.6)

34 (54.0)

0.379

-

21 (67.7)

20 (64.5)

0.786

-

Use of dexmedetomidine, n (%)

75 (78.9)

30 (93.8)

45 (71.4)

0.031

0.55

29 (93.5)

28 (90.3)

1.000

0.10

Use of midazolam, n (%)

35 (36.8)

14 (48.3)

21 (33.3)

0.371

0.15

13 (41.9)

12 (38.7)

1.000

0.07

Use of propofol, n (%)

68 (72.3)

23 (74.2)

45 (71.4)

1.000

0.01

22 (73.3)

24 (77.4)

0.772

-0.09

 Sedation and analgesic status

Number of days for RASS-4 and -5

0 [0–3]

0 [0–6]

2 [0–7.5]

< .001

-

0 [0–7]

0 [0–8]

0.121

-

Dairy mean RASS Score

-1 [0—-2]

-1 [0- -2]

-2 [0—-2]

0.42

-

-1 [0- -2]

-2 [0—-2]

0.489

-

Number of days for RASS 0 to 4

0 [0–0]

0 [0–0]

2 [0–2]

0.187

-

0 [0–0]

0 [0–0]

0.687

-

Maximum CPOT, median [IQR]

1 [0–2]

0 [0–1]

1 [0–2]

0.848

-

0 [0–2]

0 [0–2]

0.832

-

 Inflammation response data

IL-6 at ICU admission (pg/ml)

226 [80.6–1252.5]

258 [105–1723]

175 [58.6–1195]

0.335

-

256 [104–1990]

291 [30.5–753.8]

0.404

-

CRP at ICU admission (mg/dL)

8.8 [2–17.5]

12.1 [7.7–22.2]

7.0 [1.7–15.3]

0.01

-

12.1 [7.7–22.2]

6.8 [2.0–17.6]

0.061

-

CRP at ICU days 3 (mg/dL)

11.7 [4.9–17]

12.1 [6.5–18.9]

11.2 [4.1–16.8]

0.292

-

11.7 [6.0–17.0]

12.6 [3.2–16.1]

0.508

-

CRP at ICU discharge (mg/dL)

7.1 [2.5–11.6]

4.6 [1.8–11.5]

7.2 [3.7–12]

0.122

-

4.5 [1.8–11.1]

8.8 [4.8–15.9]

0.039

-