Table 3 Descriptive statistics. Surgical prognostic factors

Tourniquet duration

N/A

 (mean [SD] min)

59.0 (21.5)

n = 231 (missing n = 7)

Tourniquet pressure

N/A

 (mean [SD] mmHg)

292.5 (29.1)

n = 231 (missing n = 3)

Surgical approach, N (%)

N/A

 Parapatellar TKA

228 (95.8%)

 Subvastus TKA

10 (4.2%)

 Posterior approach THA

71 (61.2%)

 Direct anterior approach THA

22 (19.0%)

 Direct superior approach THA

23 (19.8%)

Robot-assisted surgery, N (%)

0.16

 No

318 (89.8%)

210 (88.2%)

108 (93.1%)

 Yes

36 (10.2%)

28 (11.8%)

8 (6.9%)

Duration of surgery (min)

0.67

 Median (IQR)

79 (70, 93)

79 (71, 91)

79 (67, 100)

 Range

(37–178)

(37–178)

(49–167)

Anaesthetic method, N (%)

 GA only

97 (27.4%)

57 (23.9%)

40 (34.5%)

0.04*

 GA + spinal LA

198 (55.9%)

145 (60.9%)

53 (45.7%)

0.07

 Sedation + spinal LA

55 (15.5%)

34 (14.3%)

21 (18.1%)

0.35

 Other (intrathecal morphine)

4 (1.1%)

2 (0.8%)

2 (1.7%)

N/A

Initial analgesia, N (%)

 Intra-operative LIA

294 (83.1%)

214 (89.9%)

80 (69.0%)

< 0.001*

 PCA

76 (21.5%)

49 (20.6%)

27 (23.3%)

0.56

 Oral analgesia only

27 (7.6%)

7 (2.9%)

20 (17.2%)

< 0.001*

 Intra-articular catheter

113 (47.5%)

N/A

 Single-shot regional block

31 (13.0%)

N/A

 Ambulatory regional block

25 (10.5%)

N/A