Demographic and operative characteristics (table created by the authors)
| 2016 | 2019 | P value | |
| Total | 211 | 201 | 0.19 |
| Hip replacement | 87 (41.2) | 70 (34.8) | |
| Knee replacement | 124 (58.8) | 131 (65.2) | |
| Gender—female (percent) | 119 (56.4) | 122 (60.7) | 0.42 |
| Hip replacement | 53 (60.9) | 41 (58.6) | 0.87 |
| Knee replacement | 66 (53.2) | 81 (61.8) | 0.21 |
| Age (years) | 68 (61–77) | 70 (62–75) | 0.89 |
| Hip replacement | 69 (61–78) | 67 (57–75) | 0.33 |
| Knee replacement | 68 (62–76) | 70 (64–75) | 0.53 |
| Calculated eGFR (mL/min) | 73 (62–82) | 78 (63–90) | 0.02 |
| Hip replacement | 71 (60–83) | 80 (62–96) | 0.05 |
| Knee replacement | 75 (64–81) | 75 (63–90) | 0.22 |
| CKD stage (percent) | 0.01 | ||
| 1 | 29 (13.7) | 51 (24.4) | |
| 2 | 138 (65.4) | 115 (57.2) | |
| 3A | 40 (19.0) | 28 (13.9) | |
| 3B | 4 (1.9) | 7 (3.5) | |
| ASA score (per cent) | 0.007 | ||
| 1 | 7 (3.3) | 1 (0.5) | |
| 2 | 130 (61.6) | 100 (49.8) | |
| 3 | 73 (34.6) | 99 (49.3) | |
| 4 | 1 (0.5) | 1 (0.5) | |
| ASA score—hip replacement (per cent) | 0.28 | ||
| 1 | 6 (6.9) | 1 (1.4) | |
| 2 | 46 (52.9) | 37 (52.9) | |
| 3 | 34 (39.1) | 32 (45.7) | |
| 4 | 1 (1.1) | 0 (0.0) | |
| ASA score—knee replacement (per cent) | 0.007 | ||
| 1 | 1 (0.8) | 0 (0.0) | |
| 2 | 84 (67.7) | 63 (48.1) | |
| 3 | 39 (31.5) | 67 (51.1) | |
| 4 | 0 (0.0) | 1 (0.8) | |
| Preoperative medication use (per cent) | |||
| Diuretics | 40 (19.0) | 44 (21.9) | 0.46 |
| ARB/ACEi | 92 (43.6) | 121 (60.2) | 0.001 |
| Anticoagulants/Clopidogrel | 56 (26.5) | 22 (10.9) | <0.001 |
| Comorbidities (per cent) | |||
| Gastrooesophageal reflux disease | 24 (11.4) | 28 (13.9) | 0.46 |
| Gastrointestinal bleeding | 3 (1.4) | 2 (1.0) | 1 |
| Diabetes mellitus | 44 (20.9) | 62 (30.8) | 0.02 |
| Surgical duration (minutes) | 86 (67–103) | 78 (66–94) | 0.009 |
| Hip replacement | 87 (67–106) | 81 (69–96) | 0.31 |
| Knee replacement | 85 (68–103) | 76 (61–92) | 0.02 |
| General anaesthesia used (per cent) | 41 (19.4) | 46 (22.9) | 0.4 |
| Hip replacement | 14 (16.1) | 19 (27.1) | 0.12 |
| Knee replacement | 27 (21.8) | 27 (20.6) | 0.88 |
| Spinal anaesthesia used (per cent) | 153 (72.5) | 186 (92.5) | <0.001 |
| Hip replacement | 60 (69.0) | 60 (85.7) | 0.02 |
| Knee replacement | 93 (75.0) | 126 (96.2) | <0.001 |
| Spinal or epidural anaesthesia (per cent) | 155 (73.5) | 186 (92.5) | <0.001 |
| Hip replacement | 62 (71.3) | 60 (85.7) | 0.04 |
| Knee replacement | 93 (75.0) | 126 (96.2) | <0.001 |
| Peripheral nerve block (per cent) | 10 (4.7) | 98 (48.8) | <0.001 |
| Hip replacement | 1 (1.1) | 1 (1.4) | 1 |
| Knee replacement | 9 (7.3) | 97 (74.0) | <0.001 |
| Surgical local infiltration (per cent) | 112 (53.1) | 109 (62.6) | 0.06 |
| Hip replacement | 32 (36.8) | 40 (64.5) | 0.001 |
| Knee replacement | 80 (64.5) | 69 (61.6) | 0.69 |
| Hospital length of stay (days) | 4.1 (3.2–5.2) | 3.8 (3.0–4.9) | <0.001 |
| Hip replacement | 4.1 (3.2–5.2) | 3.1 (2.2–4.2) | 0.001 |
| Knee replacement | 4.1 (3.2–5.2) | 4.0 (3.0–5.0) | 0.04 |
| Readmission rate (per cent) | 43 (20.4) | 20 (10.0) | 0.004 |
| Hip replacement | 18 (20.7) | 2 (2.9) | 0.001 |
| Knee replacement | 25 (20.2) | 18 (13.7) | 0.18 |
| Reason for readmission (per cent) | |||
| Pain/analgesia | 6 (2.8) | 5 (2.5) | 1 |
| Constipation | 9 (4.3) | 0 (0.0) | 0.004 |
| Pain/analgesia OR constipation | 15 (7.1) | 5 (2.5) | 0.04 |
| Rule out DVT/PE | 5 (2.4) | 9 (4.5) | 0.28 |
| Other or unrelated reasons | 28 (13.3) | 15 (7.5) | 0.08 |
ACEi, angiotensin-converting enzyme inhibitor; ARB, angiotensin receptor blocker; ASA, American Society of Anesthesiologists; CKD, chronic kidney disease; DVT, deep vein thrombosis; eGFR, estimated glomerular filtration rate; PE, pulmonary embolism.