Table 1.
Patient characteristics of 16,250 total knee arthroplasties. Values are count (%) unless otherwise specified
| Variable | No tourniquet n = 3,732 | Tourniquet n = 12,518 | P value | Total n = 16,250 |
|---|---|---|---|---|
| LOS, median (IQR) | 2 (2–3) | 2 (2–3) | < 0.001 | 2 (2–3) |
| VTE | 25 (0.7) | 52 (0.4) | 0.1 | 77 (0.5) |
| BMI mean (SD) | 30.1 (5.7) | 29.4 (5.4) | < 0.001 | 29.6 (5.5) |
| Missing | 17 | 57 | 74 | |
| Age, mean (SD) | 67.7 (10) | 67.9 (9.9) | 0.2 | 67.9 (10) |
| History of VTE | 306 (8.4) | 858 (7.0) | 0.02 | 1,165 (7.3) |
| Missing | 75 | 199 | 274 | |
| Female | 2,298 (62) | 7,604 (61) | 0.6 | 9,912 (61) |
| Cardiovascular disease | 561 (15.3) | 1767 (14.2) | 0.2 | 2,332 (15) |
| Missing | 55 | 118 | 173 | |
| Pulmonary disease | 382 (10) | 1,049 (8.4) | 0.002 | 1,433 (8.9) |
| Missing | 28 | 67 | 95 | |
| Hereditary VTE | 460 (14) | 1484 (14) | 0.9 | 1,946 (14) |
| Missing | 378 | 1554 | 1,932 | |
| Potent anticoagulative | ||||
| treatment | 291 (7.8) | 848 (6.8) | 0.01 | 1,140 (7.0) |
| Smoking | 535 (15) | 1,513 (12) | < 0.001 | 2,049 (13) |
| Missing | 39 | 80 | 119 | |
| Alcohol | 283 (7.7) | 859 (6.9) | 0.2 | 1,144 (7.1) |
| Missing | 47 | 92 | 13 | |
| Living with others | 2,308 (62) | 8,461 (68) | 10,781 (67) | |
| Living alone | 1,375 (37) | 3,955 (32) | 5,335 (33) | |
| Nursing home | 17 (0.5) | 57 (0.5) | < 0.001 | 74 (0.5) |
| Missing | 32 | 45 | 77 | |
| Walking aid | 902 (25) | 2,405 (20) | < 0.001 | 3,312 (21) |
| Missing | 90 | 238 | 328 | |
| Anemia | 940 (25) | 2,943 (24) | 0.09 | 3,889 (24) |
| Missing | 19 | 151 | 170 | |
| Hypertension | 2,227 (60) | 6,262 (50) | < 0.001 | 8,501 (53) |
| Missing | 8 | 53 | 61 | |
| Hypercholesterolemia | 1,271 (35) | 4,894 (39) | < 0.001 | 6,172 (38) |
| Missing | 52 | 52 | 104 | |
| Psychiatric disorder | 380 (11) | 997 (12) | 0.3 | 1,378 (11) |
| Missing | 164 | 3,913 | 4,081 | |
| Stroke | 251 (6.9) | 749 (6.1) | 0.2 | 1,001 (6.2) |
| Missing | 78 | 153 | 231 | |
| IDDM | 93 (2.5) | 346 (2.8) | 439 (2.7) | |
| NIDDM | 403 (11) | 1,030 (8.3) | 1,434 (8.9) |
LOS = postoperative length of stay, VTE = venous thromboembolism, IQR = interquartile range, SD = standard deviation, IDDM = insulin-dependent diabetes mellitus, NIDDM = non-insulin-dependent diabetes mellitus.