Table 1. Demographic and Clinical Variables Stratified by Risk Analysis Index Score.
| Characteristic | RAI Score, No. (%) | ||||
|---|---|---|---|---|---|
| ≤10 | 11-20 | 21-30 | 31-40 | >40 | |
| Total | 811 043 (82.4) | 108 635 (11.0) | 47 304 (4.8) | 14 348 (1.5) | 3220 (0.3) |
| Age, mean/median (SD) | 56.3/58.0 (16.7) | 67.4/70.0 (16.4) | 66.4/67.0 (15.1) | 67.4/69.0 (14.8) | 66.6/68.0 (14.3) |
| Age, y | |||||
| ≤ 55 | 368 515 (45.4) | 25 986 (23.9) | 11 034 (23.3) | 3007 (21.0) | 665 (20.7) |
| 56-65 | 177 826 (21.9) | 19 811 (18.2) | 10 603 (22.4) | 3061 (21.3) | 763 (23.7) |
| 66-75 | 154 235 (19.0) | 22 667 (20.9) | 10 784 (22.8) | 3387 (23.6) | 821 (25.5) |
| >75 | 110 467 (13.6) | 40 171 (37.0) | 14 883 (31.5) | 4893 (34.1) | 971 (30.2) |
| Sex | |||||
| Male | 334 015 (41.2) | 55 707 (51.3) | 32 865 (69.5) | 10 248 (71.4) | 2434 (75.6) |
| Female | 477 028 (58.8) | 52 928 (48.7) | 14 439 (30.5) | 4100 (28.6) | 786 (24.4) |
| Race/Ethnicity | |||||
| White | 609 279 (83.7) | 80 816 (81.6) | 35 129 (81.6) | 10 268 (78.5) | 2242 (76.2) |
| Black | 80 617 (11.1) | 13 686 (13.8) | 5997 (13.9) | 2250 (17.2) | 560 (19.0) |
| Asian | 18 961 (2.6) | 2418 (2.4) | 1057 (2.5 | 295 (2.3 | 75 (2.6 |
| Hispanic | 12 980 (1.8) | 1443 (1.5) | 565 (1.3) | 187 (1.4) | 43 (1.5) |
| Native American | 5968 (0.8) | 716 (0.7) | 303 (0.7) | 86 (0.7) | 21 (0.7) |
| BMI, mean (SD) | 30.9 (12.9) | 27.3 (7.6) | 27.4 (7.4) | 26.9 (7.9) | 29.9 (7.3) |
| ASA level | |||||
| 1 | 54 355 (6.7) | 944 (0.9) | 217 (0.5) | 23 (0.2) | 1 (0.0) |
| 2 | 339 649 (41.9) | 19 036 (17.5) | 6386 (13.5) | 813 (5.7) | 54 (1.7) |
| 3 | 363 771 (44.9) | 62 554 (57.7) | 24 448 (51.8) | 5790 (40.4) | 919 (28.6) |
| 4/5 | 52 184 (6.4) | 25 947 (23.9) | 16 188 (34.3) | 7699 (53.7) | 2242 (69.7) |
| Current smoker (within 1 y) | 173 032 (21.3) | 22 297 (20.5) | 9473 (20.0) | 3067 (21.4) | 784 (24.3) |
| Functional status | |||||
| Independent | 802 653 (99.0) | 69 876 (64.3) | 20 687 (43.7) | 2976 (20.7) | 61 (1.9) |
| Partial dependent | 8390 (1.0) | 36 182 (33.3) | 15 181 (32.1) | 3016 (21.0) | 656 (20.4) |
| Total dependent | 0 | 2577 (2.4) | 11 436 (24.2) | 8356 (58.2) | 2503 (77.7) |
| Diabetes | |||||
| None | 673 992 (83.1) | 81 622 (75.1) | 34 796 (73.6) | 9975 (69.5) | 2204 (68.4) |
| Noninsulin | 36 114 (4.5) | 4944 (4.6) | 1901 (4.0) | 462 (3.2) | 105 (3.3) |
| Oral medication | 49 266 (6.1) | 7662 (7.1) | 3285 (6.9) | 1051 (7.3) | 237 (7.4) |
| Insulin | 51 671 (6.4) | 14 407 (13.3) | 7322 (15.5) | 2860 (19.9) | 674 (20.9) |
| Congestive heart failure | 2331 (0.3) | 6117 (5.6) | 3519 (7.4) | 2034 (14.2) | 830 (25.8) |
| Dyspnea | |||||
| None | 720 144 (88.8) | 86 148 (79.3) | 37 110 (78.5) | 8618 (60.1) | 1160 (36.0) |
| Moderate exertion | 88 591 (10.9 | 15 763 (14.5) | 5829 (12.3) | 1534 (10.7) | 259 (8.0) |
| At rest | 2308 (0.3) | 6724 (6.2) | 4365 (9.2) | 4196 (29.2) | 1801 (55.9) |
| Chronic obstructive pulmonary disease | 41 824 (5.2) | 12 577 (11.6) | 5826 (12.3) | 2432 (17.0) | 692 (21.5) |
| Preoperative pneumonia | 2103 (0.3) | 1973 (1.8) | 2164 (4.6) | 1652 (11.5) | 668 (20.7) |
| Preoperative ventilator | 1698 (0.2) | 2155 (2.0) | 4874 (10.3) | 3603 (25.1) | 1250 (38.8) |
| Preoperative coma | 59 (0.0) | 44 (0.0) | 269 (0.6) | 340 (2.4) | 139 (4.3) |
| Impaired sensorium | 2093 (0.3) | 2165 (2.0) | 2993 (6.3) | 2529 (17.6) | 1100 (34.2) |
| Transient ischemic attack | 27 841 (3.4) | 6358 (5.9) | 2252 (4.8) | 725 (5.1) | 185 (5.7) |
| Stroke | |||||
| None | 776 006 (95.7) | 97 270 (89.5) | 41 137 (87.0) | 11 411 (79.5) | 2540 (78.9) |
| Without deficit | 17 466 (2.2) | 5219 (4.8) | 2224 (4.7) | 677 (4.7) | 152 (4.7) |
| With deficit | 17 493 (2.2) | 6138 (5.7) | 3938 (8.3) | 2260 (15.8) | 528 (16.4) |
| Ascites | 6086 (0.8) | 3030 (2.8) | 2500 (5.3) | 1464 (10.2) | 570 (17.7) |
| Bleeding disorder | 50 312 (6.2) | 16 138 (14.9) | 8331 (17.6) | 3436 (23.9) | 1002 (31.1) |
| Disseminated cancer | 0 | 10 397 (9.6) | 12 777 (27.0) | 3416 (23.8) | 1247 (38.7) |
| Chemotherapy | 0 | 7587 (7.0) | 7047 (14.9) | 1783 (12.4) | 644 (20.0) |
| Radiotherapy | 0 | 3474 (3.2) | 5588 (11.8) | 1279 (8.9) | 318 (9.9) |
| Steroids | 27 641 (3.4) | 7021 (6.5) | 3345 (7.1) | 1353 (9.4) | 466 (14.5) |
| Transfusion | 4762 (0.6 | 2985 (2.7 | 2375 (5.0 | 1173 (8.2 | 383 (11.9) |
| Weight loss | 139 (0.0) | 19 795 (18.2) | 5039 (10.7) | 4241 (29.6) | 1186 (36.8) |
| Open/infected wound | 32 324 (4.0) | 16 166 (14.9) | 9951 (21.0) | 4358 (30.4) | 1129 (35.1) |
| Dialysis | 5121 (0.6) | 10 408 (9.6) | 5194 (11.0) | 2155 (15.0) | 749 (23.3) |
| Preoperative renal failure | 1162 (0.1) | 3093 (2.8) | 2055 (4.3) | 1321 (9.2) | 666 (20.7) |
| Hypertension requiring medications | 407 460 (50.2) | 71 080 (65.4) | 29 665 (62.7) | 9434 (65.8) | 2124 (66.0) |
| Type of operation | |||||
| General | 599 503 (73.9) | 70 003 (64.4) | 33 325 (70.4) | 10 183 (71.0) | 2429 (75.4) |
| Vascular | 120 128 (14.8) | 26 096 (24.0) | 9557 (20.2) | 3056 (21.3) | 595 (18.5) |
| Thoracic | 8179 (1.0) | 1939 (1.8) | 1197 (2.5) | 325 (2.3) | 87 (2.7) |
| Cardiac | 9301 (1.1) | 2203 (2.0) | 572 (1.2) | 200 (1.4) | 34 (1.1) |
| Orthopedic | 73 932 (9.1) | 8394 (7.7) | 2653 (5.6) | 584 (4.1) | 75 (2.3) |
| Length of stay, d, Mean/Median (SD) | 4.4/3 (6.1) | 8.5/6 (10.7) | 11.3/7 (13.9) | 14/9 (16.9) | 15.4/10 (17.8) |
| Emergency operation | 133 137 (16.4) | 22 071 (20.3) | 12 523 (26.5) | 5737 (40.0) | 1733 (53.8) |
| Procedural mortality risk | |||||
| <1% (low) | 483 286 (59.6) | 28 352 (26.1) | 6820 (14.4) | 1103 (7.7) | 140 (4.3) |
| >1% (high) | 327 757 (40.4) | 80 283 (73.9) | 40 484 (85.6) | 13 245 (92.3) | 3080 (95.7) |
Abbreviations: ASA, American Society of Anesthesiologists; BMI, body mass index (calculated as weight in kilograms divided by height in meters squared).