Demographic and procedural data
| Patients with thromboprophylaxis | Patients without thromboprophylaxis | P value*† | |
| Sample size, n | 21,009 | 44,805 | |
| Demographic data | |||
| Female sex, n (%) | 10,162 (48) | 23,830 (53) | <0.001 |
| Mean age (SD) in years | 64.0 (15) | 58.4 (18) | <0.001 |
| Mean BMI (SD) in kg/m2 | 28.2 (6) | 28.1 (6) | <0.01 |
| ASA status, n (%) | |||
| ASA 1 | 1475 (7) | 5931 (13) | <0.001 |
| ASA 2 | 7900 (38) | 21,938 (49) | |
| ASA 3 | 10,897 (52) | 16,349 (37) | |
| ASA ≥4 | 737 (4) | 587 (1) | |
| Mean year of surgery (SD) | 2012 (3) | 2014 (3) | <0.001 |
| Renal insufficiency‡, n (%) | 5715 (27) | 7244 (16) | <0.001 |
| Procedural data | |||
| Peripheral puncture site, n (%) | 9386 (45) | 25,299 (57) | <0.001 |
| Neuraxial puncture site, n (%) | 11,623 (55) | 19,506 (44) | |
| Awake during block placement, n (%) | 9915 (47) | 17,949 (40) | <0.001 |
| Sedated/general anesthesia, n (%) | 11,094 (53) | 26,856 (60) | |
| Single shot, n (%) | 3792 (18) | 10,807 (24) | <0.001 |
| Catheter, n (%) | 17,217 (82) | 33,998 (76) | |
| Use of ultrasound, n (%) | 4221 (20) | 15,682 (35) | <0.001 |
| Multiple skin puncture, n (%) | 3797 (18) | 5742 (13) | <0.001 |
| Bloody tap | 626 (3.0) | 909 (2.0) | <0.001 |
*P value compares patients with thromboprophylaxis versus patients without thromboprophylaxis.
†Mann-Whitney U test used to compare means and χ2 test used to compare proportions.
‡Defined as dialysis or CKD EPI < 60 mL/min/1.73 m².
ASA, American Society of Anesthesiologists; BMI, body mass index; CKD EPI, Chronic Kidney Disease Epidemiology Collaboration estimating equation for eGFR.