Table 1 Baseline characteristics

n

220

106

114

Age (mean (SD))

68.2 (6.2)

67.8 (5.7)

68.5 (6.7)

Male Gender, n (%)

129 (58.6)

60 (56.6)

69 (60.5)

Weight kg (mean (SD))

95.8 (20.2)

96.0 (19.5)

95.7 (20.9)

BMI (mean (SD))

33.3 (6.3)

33.3 (6.1)

33.4 (6.4)

ASA Status, n (%)

 1

4 ( 1.8)

1 ( 0.9)

3 ( 2.6)

 2

100 (45.5)

48 (45.3)

52 (45.6)

 3

112 (50.9)

54 (50.9)

58 (50.9)

 4

2 ( 0.9)

2 ( 1.9)

0 ( 0.0)

 not recorded

2 ( 0.9)

1 ( 0.9)

1 ( 0.9)

 Charlson co-morbidity index (mean (SD))

2.6 (0.9)

2.6 (1.00)

2.6 (0.8)

 Hypertension, n (%)

140 (63.6)

70 (66.0)

70 (61.4)

 Congestive Heart Failure, n (%)

3 ( 1.4)

2 ( 1.9)

1 ( 0.9)

 Prior Myocardial Infarction, n (%)

8 ( 3.6)

4 ( 3.8)

4 ( 3.5)

 Smoker, n (%)

49 (22.3)

24 (22.6)

25 (21.9)

 Diabetes, n (%)

32 (14.5)

16 (15.1)

16 (14.0)

 STOP-Bang Score (mean (SD))

5.0 (1.3)

5.0 (1.4)

5.0(1.2)

 ESS Score (mean (SD))

6.2 (4.2)

6.7 (4.2)

5.8 (4.1)

 Knee Surgery, n (%)

139 (63.2)

68 (64.2)

71 (62.3)

MiniCog Score, n (%)

 ≤ 2

10 ( 4.5)

4 ( 3.8)

6 ( 5.3)

 > 2

177 (80.5)

87 (82.1)

90 (78.9)

 Missing

33 (15.0)

15 (14.2)

18 (15.8)