Skip to main content

Table 5 Effect size of two types of anaesthesia on LOS (Days) in prespecified and exploratory subgroups in Each Subgroup

From: Two types of anaesthesia and length of hospital stay in patients undergoing unilateral total knee arthroplasty (TKA): a secondary analysis based on a single-centre retrospective cohort study in Singapore

Anaesthesia LOS (Days)
N β 95%CI Interaction P-value
Age (years) group     0.0072
  < 60 472 0.45 (− 0.03, 0.92)  
  > =60, < 70 1011 0.56 (− 0.07, 1.20)  
  > =70, < 80 744 1.99 (1.15, 2.83)  
  > =80 139 2.46 (−0.29, 5.20)  
Sex     0.0588
 Female 1794 0.62 (0.19, 1.05)  
 Male 572 1.58 (0.49, 2.67)  
Ethnicity     0.8872
 Chinese 1987 0.86 (0.38, 1.34)  
 Malay 169 0.78 (−0.04, 1.60)  
 Indian 137 0.40 (− 0.53, 1.32)  
 Others 73 1.53 (−0.46, 3.52)  
BMI group     0.0067
  < 25 726 1.87 (1.06, 2.67)  
  > =25, < 30 963 0.28 (−0.36, 0.93)  
  > =30, < 35 467 0.38 (−0.26, 1.01)  
  > =35 153 0.96 (−0.17, 2.09)  
ASA Status     0.5077
 1 161 −0.01 (− 0.74, 0.73)  
 2 2058 0.84 (0.46, 1.21)  
 3 147 1.16 (0.46, 1.21)  
Hb(g/dL) group     0.9170
  < 11 164 1.08 (−1.04, 3.19)  
  > =11, < 13 888 0.92 (0.17, 1.67)  
  > =13 1314 0.79 (0.32, 1.26)  
duration of surgery (mins) group     0.5324
  < 60 320 1.00 (0.28, 1.72)  
  > =60, < 120 1903 0.72 (0.25, 1.18)  
  > =120 143 1.63 (−0.77, 4.03)  
Smoking     0.1232
 No 2141 0.93 (0.48, 1.37)  
 Yes 225 −0.23 (−1.13, 0.68)  
OSA     0.5106
 No 2152 0.88 (0.43, 1.32)  
 Yes 214 0.39 (−0.40, 1.18)  
DM     0.2677
 No 1920 0.72 (0.30, 1.15)  
 Yes 446 1.32 (0.12, 2.51)  
IHD     0.0002
 No 2239 0.65 (0.25, 1.05)  
 Yes 127 4.05 (1.07, 7.02)  
CCF     0.0423
 No 2348 0.91 (0.52, 1.29)  
 Yes 18 −5.88 (−36.03, 24.28)  
CVA     0.3150
 No 2321 0.81 (0.39, 1.23)  
Yes 45 2.34 (0.34, 4.33)  
Creatinine > 2 mg/dl     < 0.0001
 No 2090 1.06 (0.64, 1.47)  
 Not recorded 258 −0.43 (−1.55, 0.68)  
 Yes 18 −7.68 (−26.62, 11.27)  
DM on insulin     0.1413
 No 1764 1.07 (0.57, 1.57)  
 Not recorded 563 0.09 (−0.62, 0.79)  
 Yes 39 1.04 (−1.10, 3.17)  
Day of week of operation     0.1282
 Monday 390 1.08 (−0.34, 2.49)  
 Tuesday 539 0.37 (−0.29, 1.04)  
 Wednesday 405 0.40 (−0.28, 1.08)  
 Thursday 533 0.60 (0.01, 1.18)  
 Friday 378 2.08 (0.60, 3.57)  
 Saturday 121 0.15 (−0.69, 0.99)  
  1. Abbreviations: LOS Length of stay, ASA American Society of Anesthesiologist Physical Status, OSA Obstructive sleep apnea, DM Diabetes mellitus, IHD Ischaemic heart disease, CCF Congestive cardiac failure, CVA Cerebrovascular accidents