Table I.
Preoperative characteristics for the 2005-2010 National Surgical Quality Improvement Program (NSQIP) dataset
| Category | Preoperative variable | N (%) | |
|---|---|---|---|
| Cardiac | Angina within 1 month | Yes | 381 (2.2) |
| Cardiac surgery prior | Yes | 4279 (24.2) | |
| Congestive heart failure | Yes | 120 (0.7) | |
| Myocardial infarction (within 6 months) | Yes | 218 (1.2) | |
| Percutaneous coronary intervention prior | Yes | 3481 (19.7) | |
| Circulatory | Bleeding disorder | Yes | 2497 (14.1) |
| Previous peripheral arterial revascularization or amputation | Yes | 1720 (9.7) | |
| Rest pain in lower extremity | Yes | 121 (0.7) | |
| General | Age, years | <60 | 1896 (10.7) |
| 60-69 | 5465 (30.9) | ||
| 70-79 | 6808 (38.5) | ||
| ≥80 | 3523 (19.9) | ||
| American Society of Anesthesiologists class | 1 | 439 (2.5) | |
| 2 | 4641 (26.3) | ||
| 3 | 11,238 (63.6) | ||
| 4 | 1362 (7.7) | ||
| 5 | 3 (0.02) | ||
| Body mass index, median (interquartile range), kg/m2 | 28.5 (25.4-32.3) | ||
| Corticosteroid use (chronic) | Yes | 319 (1.8) | |
| Diabetes mellitus | On insulin | 2844 (16.1) | |
| On medication | 1934 (10.9) | ||
| Functional status | Dependent | 290 (1.6) | |
| Hypertension | Yes | 15,144 (85.6) | |
| Race | American Indian | 44 (0.3) | |
| Asian/Pacific Islander | 176 (1.0) | ||
| Black | 580 (3.3) | ||
| Hispanic | 506 (2.9) | ||
| Unknown | 1037 (5.9) | ||
| White | 15,162 (86.6) | ||
| Sex | Male | 10,217 (57.9) | |
| Female | 7437 (42.1) | ||
| Systemic inflammatory response syndrome | Yes | 78 (0.5) | |
| Transition (admitted from:) | Home | 17,520 (99.0) | |
| Acute care | 89 (0.5) | ||
| VA acute care | 1 (0.01) | ||
| Chronic care | 55 (0.3) | ||
| VA chronic care | 0 | ||
| Others | 27 (0.2) | ||
| Weight loss >10% within 6 months | Yes | 71 (0.4) | |
| Laboratory | Albumin | Abnormal | 914 (5.2) |
| Alkaline phosphatase | Abnormal | 544 (3.1) | |
| Blood urea nitrogen | Abnormal | 7310 (41.3) | |
| Creatinine | Abnormal | 2197 (12.4) | |
| Hematocrit | Abnormal | 3379 (19.1) | |
| Platelets | Abnormal | 2360 (13.3) | |
| Prothrombin time | Abnormal | 3311 (18.7) | |
| Partial thromboplastin time | Abnormal | 1081 (6.1) | |
| Serum glutamic oxaloacetic transaminase | Abnormal | 922 (5.2) | |
| Sodium | Abnormal | 1950 (11.0) | |
| White blood cell count | Abnormal | 1700 (9.6) | |
| Renal | Dialysis (preoperative) | Yes | 143 (0.8) |
| Respiratory | COPD | Yes | 1755 (9.9) |
| Dyspnea | At rest or moderate exertion | 3310 (18.7) | |
| Pneumonia (preoperative) | Yes | 14 (0.1) | |
| Social | Alcohol intake within last 2 weeks | Yes | 746 (4.2) |
| Smoking within past year | Yes | 4588 (25.9) | |
| Therapy | Anesthesia | General | 14,649 (82.8) |
| Regional | 3040 (17.2) |
COPD, Chronic obstructive pulmonary disease; VA, Veterans Affairs.