Table 2. Operative Characteristics and Postoperative Laboratory Dataa.
| Characteristic | Mean (SD) | |||||
|---|---|---|---|---|---|---|
| Procedures | Proteinuria | |||||
| Negative | Trace | 1+ | 2+ | 3+ | ||
| Overall, No. | 153 767 | 86 571 | 31 676 | 24 603 | 8457 | 2460 |
| Work RVU, U | 20.1 (7.5) | 20.6 (7.2) | 19.9 (7.7) | 19.2 (8.0) | 18.6 (7.8) | 18.1 (7.9) |
| Total operation time, h | 2.7 (1.7) | 2.6 (1.6) | 2.6 (1.7) | 2.6 (1.7) | 2.5 (1.7) | 2.5 (1.7) |
| Length of postoperative surgical stay, d | 5.2 (4.0) | 5.0 (3.7) | 5.6 (4.2) | 6.0 (4.5) | 6.3 (4.7) | 6.2 (4.6) |
| Wound classification, No. (%) | ||||||
| Clean | 97 855 (63.6) | 59 639 (68.8) | 19 514 (61.5) | 13 190 (53.8) | 4289 (50.4) | 1223 (51.5) |
| Clean/contaminated | 41 338 (26.9) | 21 238 (24.5) | 9042 (28.5) | 7680 (31.3) | 2668 (31.4) | 710 (29.9) |
| Contaminated | 6833 (4.4) | 2793 (3.2) | 1477 (4.7) | 1698 (6.9) | 667 (7.8) | 198 (8.3) |
| Infected | 7729 (5.0) | 2959 (3.4) | 1703 (5.4) | 1937 (7.9) | 885 (10.4) | 245 (10.3) |
| Discharge destination, No. (%) | ||||||
| Community | 135 852 (88.4) | 77 623 (89.6) | 27 829 (87.7) | 21 222 (86.6) | 7189 (84.5) | 1989 (83.7) |
| Subacute care | 17 915 (11.7) | 9008 (10.4) | 3909 (12.3) | 3289 (13.4) | 1322 (15.5) | 387 (16.3) |
| Estimated intraoperative blood loss, mL | 337.4 (276.7) | 345.1 (259.5) | 340.0 (268.5) | 327.7 (283.7) | 322.3 (325.7) | 303.0 (266.0) |
| Estimated glomerular filtration rate, mL/min/1.73 m2 | ||||||
| Highest | 79.3 (46.2) | 79.5 (46.3) | 81.1 (46.2) | 79.7 (46.2) | 74.1 (44.7) | 63.3 (42.3) |
| Lowest | 64.4 (39.2) | 65.4 (39.5) | 65.5 (39.2) | 63.1 (38.7) | 58.0 (37.2) | 49.4 (34.9) |
| Systolic blood pressure, mm Hg | ||||||
| Highest | 151.7 (19.6) | 150.4 (18.9) | 152.5 (19.7) | 155.1 (20.3) | 161.0 (21.5) | 166.0 (22.4) |
| Lowest | 107.5 (14.8) | 106.7 (14.3) | 107.1 (14.9) | 107.8 (15.8) | 109.7 (16.7) | 113.1 (17.9) |
| White blood cell count, /μL | ||||||
| Highest | 11 600 (4500) | 8400 (3000) | 8200 (3200) | 8100 (3200) | 8200 (3000) | 8300 (3300) |
| Lowest | 8.3 (3.1) | 11.5 (4.2) | 11.7 (4.9) | 11.9 (5.0) | 12.0 (4.7) | 12.2 (6.0) |
| Serum creatinine, mg/dL | ||||||
| Highest | 1.1 (0.7) | 1.1 (0.6) | 1.2 (0.7) | 1.3 (0.9) | 1.5 (1.0) | 1.9 (1.5) |
| Lowest | 0.9 (0.4) | 0.9 (0.4) | 0.9 (0.4) | 1.0 (0.5) | 1.2 (0.7) | 1.4 (1.0) |
| Serum urea nitrogen, mg/dL | ||||||
| Highest | 17.5 (10.5) | 16.6 (9.1) | 17.9 (10.8) | 19.9 (12.9) | 24.4 (16.1) | 29.2 (18.3) |
| Lowest | 12.0 (6.9) | 11.5 (6.0) | 11.9 (7.0) | 13.0 (8.3) | 16.1 (11.1) | 20.0 (13.2) |
| Sodium, mEq/L | ||||||
| Highest | 138.4 (3.3) | 138.1 (3.2) | 138.5 (3.4) | 138.7 (3.6) | 139.1 (3.7) | 139.4 (3.8) |
| Lowest | 135.0 (3.4) | 134.9 (3.4) | 134.9 (3.4) | 134.9 (3.5) | 135.0 (3.6) | 135.1 (3.6) |
| Potassium, mEq/L | ||||||
| Highest | 3.7 (1.6) | 3.6 (1.6) | 3.8 (1.6) | 3.9 (1.5) | 4.0 (1.4) | 4.2 (1.4) |
| Lowest | 3.2 (1.4) | 3.2 (1.4) | 3.2 (1.4) | 3.3 (1.3) | 3.4 (1.2) | 3.5 (1.2) |
| International normalized ratio | ||||||
| Highest | 1.5 (0.8) | 1.5 (0.8) | 1.5 (0.8) | 1.5 (0.8) | 1.5 (0.8) | 1.5 (1.0) |
| Lowest | 1.1 (0.2) | 1.2 (0.2) | 1.2 (0.2) | 1.2 (0.2) | 1.2 (0.2) | 1.2 (0.2) |
Abbreviation: RVU, relative value unit.
SI conversion factors: To convert creatinine to millimoles per liter, multiply by 88.4; urea nitrogen to millimoles per liter, multiply by 0.357; white blood cell count to ×109/L, multiply by 0.001; conversion of potassium and sodium to millimoles per liter is 1 to 1.
a
All differences were significant at P < .001, determined with a χ2 test for categorical variables and a t test for continuous variables.