Table 1.
Demographic and Baseline Characteristics of the Population
| Patient variable | Missing | Summary statistics, N = 9141 |
|---|---|---|
| Age (y) | 64 ± 13 | |
| Male | 6206 (68) | |
| BMI (kg/m2) | 1 | 29 ± 6 |
| Race | ||
| White | 8264 (90) | |
| Black | 312 (4) | |
| Other | 565 (6) | |
| ASA physical classification | ||
| III | 751 (8) | |
| IV | 8390 (92) | |
| Comorbidities | ||
| Endocarditis | 368 (4) | |
| Hypertension | 3 | 6698 (73) |
| Atrial fibrillation or flutter | 106 | 2320 (26) |
| Left ventricular dysfunction | 216 | |
| Normal | 7888 (88) | |
| Mild | 670 (8) | |
| Moderate | 289 (3) | |
| Moderate-severe | 44 (<1) | |
| Severe | 34 (<1) | |
| Myocardial infarction | 9 | 1049 (12) |
| Pulmonary hypertension | 610 (7) | |
| Chronic lung disease | 3 | 1788 (20) |
| Moderate or severe mitral insufficiency | 2894 (32) | |
| Carotid artery disease | 1 | 473 (5) |
| Peripheral vascular disease | 547 (6) | |
| Diabetes mellitus | 1 | 1902 (21) |
| Stroke | 19 | 557 (6) |
| Preoperative medication | ||
| Aspirin | 2 | 3027 (33) |
| Beta Blocker | 5912 (65) | |
| ACE or ARB | 4093 (45) | |
| Statin | 2915 (32) | |
| Diuretic | 8619 (94) | |
| Inhaled steroids | 538 (6) | |
| Inhaled bronchodilator | 1054 (12) | |
| Preoperative laboratory measurements | ||
| Hematocrit (%) | 357 | 42 [39, 45] |
| Creatinine (mg/dL) | 37 | 0.98 [0.83, 1.14] |
| Surgery characteristics | ||
| Surgery type | ||
| Aortic valve procedure | 3186 (35) | |
| Mitral valve procedure | 2353 (26) | |
| CABG | 1559 (17) | |
| Aortic resection, replacement, or anastomosis | 1237 (14) | |
| Other valve surgery | 806 (9) | |
| Pre-CPB arterial Pao2 | 9 | 151 [112, 189] |
| CPB length (min) | 93 [68, 127] | |
| Total fluid (mL) | 2900 [2250, 3550] | |
| Total blood transfusion (unit) | 0 [0, 1] | |
| Ultrafiltration | 998 (11) | |
Data are summarized as median [Q1, Q3], mean ± SD, or N (%).
Abbreviations: ACE, angiotensin converting enzyme; ARB, angiotensin receptor blocker; ASA, American Society of Anesthesiologists; BMI, body mass index; CABG, coronary artery bypass grafting; CPB, cardiopulmonary bypass; Pao2, arterial oxygen partial pressure.