Table 1.
Descriptive characteristics of all total hip replacement (THR) patients according to red blood cell transfusion within 8 days of surgery.
| Transfusion n = 9,063 |
No transfusion n = 19,024 |
Standardized mean difference*** | |
|---|---|---|---|
| Age (years) | |||
| 10-49 | 338 (3.7%) | 1363 (7.2%) | 0.18797 |
| 50-59 | 834 (9.2%) | 3162 (16.6%) | 0.22038 |
| 60-69 | 2098 (23.2%) | 6334 (33.3%) | 0.18585 |
| 70-79 | 3189 (35.2%) | 5957 (31.3%) | 0.11451 |
| +80 | 2604 (28.7%) | 2208 (11.6%) | 0.42107 |
| Sex | |||
| Female | 6440 (71.1%) | 10450 (54.9%) | 0.36876 |
| Primary hip diagnosis | |||
| Primary arthrosis | 5646 (62.3%) | 15588 (81.9%) | 0.40642 |
| Trauma | 2546 (28.1%) | 1628 (8.6%) | 0.48898 |
| Other | 871 (9.6%) | 1808 (9.5%) | 0.02348 |
| Comorbidity history (yes) | |||
| Myocardial infarction | 491 (5.4%) | 717 (3.8%) | 0.07073 |
| Congestive heart failure | 612 (6.8%) | 600 (3.2%) | 0.17886 |
| Peripheral vascular disease | 442 (4.9%) | 645 (3.4%) | 0.05825 |
| Cerebrovascular disease | 990 (10.9%) | 1010 (5.3%) | 0.22239 |
| Dementia | 165 (1.8%) | 106 (0.6%) | 0.11135 |
| Chronic pulmonary disease | 815 (9.0%) | 1227 (6.5%) | 0.09349 |
| Connective tissue disease | 679 (7.5%) | 972 (5.1%) | 0.11434 |
| Peptic ulcer disease | 654 (7.2%) | 745 (3.9%) | 0.15010 |
| Mild liver disease | 167 (1.8%) | 214 (1.1%) | 0.05590 |
| Diabetes (type I and II) | 544 (6.0%) | 764 (4.0%) | 0.08144 |
| Hemiplegia | 19 (0.2%) | 19 (0.1%) | 0.01715 |
| Moderate to severe renal disease | 236 (2.6%) | 229 (1.2%) | 0.13977 |
| Diabetes with end organ damage | 274 (3.0%) | 326 (1.7%) | 0.10146 |
| Any tumor | 1151 (12.7%) | 1637 (8.6%) | 0.16577 |
| Leukemia | 36 (0.4%) | 35 (0.2%) | 0.05114 |
| Lymphoma | 69 (0.8%) | 76 (0.4%) | 0.06085 |
| Moderate to severe liver disease | 63 (0.7%) | 39 (0.2%) | 0.07666 |
| Metastatic solid tumor | 141 (1.6%) | 121 (0.6%) | 0.11523 |
| Fixation technique | |||
| Cemented | 4060 (44.8%) | 6170 (32.4%) | 0.26193 |
| Cementless | 2118 (23.4%) | 7486 (39.4%) | 0.37578 |
| Hybrid | 2885 (31.8%) | 5368 (28.2%) | 0.09093 |
| Type of anesthesia | |||
| Regional | 5929 (65.4%) | 14622 (76.9%) | 0.29165 |
| Universal and Combined | 3134 (34.6%) | 4402 (23.1%) | 0.29165 |
| Duration of surgery (minutes) | |||
| 0-60 | 1819 (20.1%) | 7439 (39.1%) | 0.34220 |
| 61-120 | 6199 (68.4%) | 11097 (58.3%) | 0.10558 |
| >121 | 1045 (11.5%) | 488 (2.6%) | 0.34021 |
| 20 hospitals performing the THR procedures* | |||
| Prophylaxis for heterotopic bone formations ** | |||
| Yes | 600 (6.6%) | 1317 (6.9%) | 0.01945 |
| No | 8463 (93.4%) | 17707 (93.1%) | 0.02058 |
| Year of surgery | |||
| 1999 | 114 (1.3%) | 115 (0.6% | 0.10403 |
| 2000 | 731 (8.1%) | 764 (4.0%) | 0.11245 |
| 2001 | 623 (6.9%) | 1353 (7.1%) | 0.05878 |
| 2002 | 1123 (12.4%) | 1757 (9.2%) | 0.19310 |
| 2003 | 989 (10.9%) | 1669 (8.8% | 0.13441 |
| 2004 | 1103 (12.2%) | 2570 (13.5%) | 0.01450 |
| 2005 | 1410 (15.6%) | 3148 (16.6%) | 0.08021 |
| 2006 | 1579 (17.4%) | 3820 (20.1%) | 0.19120 |
| 2007 | 1390 (15.4%) | 3828 (20.1%) | 0.12261 |
Data are shown in number (%) unless otherwise specified. * Each of the 20 hospitals performing the THR procedures was treated as separate covariate. ** Anti -rheumatic drugs were used as prophylaxis for heterotopic bone formation. *** A standardized mean difference that exceeds 0.1 is indicative of significant imbalance between groups.