Table 1 –
Patient and surgical characteristics according to preoperative anemia status*
| Preoperative Anemia (N=1234) |
No Preoperative Anemia (N=2883) |
Absolute standardized difference | |
|---|---|---|---|
| Patient characteristics | |||
| Age, years | 72 (64, 79) | 69 (59, 76) | 0.31 |
| Sex | 0.23 | ||
| Female | 438 (35%) | 1349 (47%) | |
| Male | 796 (65%) | 1534 (53%) | |
| BMI, kg/m2 | 28.5 (25.3, 32.7) | 28.2 (24.7, 32.4) | 0.08 |
| Smoking history | |||
| Current | 96 (8%) | 246 (9%) | 0.03 |
| Former | 554 (45%) | 1083 (38%) | 0.15 |
| Never | 584 (47%) | 1554 (54%) | 0.13 |
| Preoperative lab values | |||
| Hemoglobin, g/dL | 11.5 (10.7, 12.1) | 13.8 (13.2, 14.5) | 2.43 |
| Creatinine, mg/dL | 1.1 (0.9, 1.5) | 1.0 (0.8, 1.1) | 0.45 |
| Platelet count, × 109/L | 206 (165, 263) | 209 (176, 248) | 0.07 |
| Comorbidities | |||
| Charlson score | 6 (4, 8) | 4 (3, 6) | 0.67 |
| Kidney disease | 376 (30%) | 232 (8%) | 0.59 |
| Diabetes with complications | 148 (12%) | 116 (4%) | 0.30 |
| Hypertension | 889 (72%) | 1759 (61%) | 0.24 |
| Surgical characteristics | |||
| Valve surgery | 837 (68%) | 2043 (71%) | 0.07 |
| CPB duration, minutes | 84 (62, 111) | 78 (55, 102) | 0.19 |
| Total intraoperative RBCs, units | 0.74 | ||
| None | 472 (38%) | 2220 (77%) | |
| 1–2 | 460 (37%) | 497 (17%) | |
| 3–4 | 228 (18%) | 133 (5%) | |
| 5+ | 74 (6%) | 33 (1%) |
BMI – body mass index; CPB – cardiopulmonary bypass; RBC – red blood cell.
*
Continuous and categorical variables are presented as median (25th percentile, 75th percentile) and frequency (percentage) respectively.