Patient comorbidity characteristics across Clavien grades.
| Characteristic | Clavien Grade | P Value | |
| Minor | Major | ||
| Diabetes mellitus | 14.5% | 54.2% | <0.001 |
| Smoking status | 14.1% | 16.8% | 0.526 |
| Cigarette pack-years | <0.001 | ||
| Alcohol consumption, >2 drinks/d | 2.4% | 4.5% | 0.027 |
| Preoperative functional health status | 0.967 | ||
| Independent | 93% | 94.1% | |
| Partially dependent | 5.5% | 4.7% | |
| Totally dependent | 1% | 0.8% | |
| Ventilator-dependent | 0.3% | 0.2% | 0.625 |
| Chronic obstructive pulmonary disease | 4.6% | 4.7% | 0.645 |
| Ascites | 0.1% | 0.0% | 0.202 |
| Congestive heart failure | 0.4% | 0.3% | 0.546 |
| History of myocardial infarction 6 mo prior | 0% | 0% | 0.55 |
| Previous percutaneous coronary intervention | 5.1% | 9.0% | 0.001 |
| Previous cardiac surgery | 4.8% | 6.0% | 0.341 |
| Hypertension | 54.7% | 49.8% | 0.41 |
| Revascularization/amputation for peripheral vascular disease | 0.5% | 0.3% | <0.001 |
| Rest pain/gangrene | 0% | 0% | 0.55 |
| Acute renal failure | 0.1% | 0.2% | 0.063 |
| Preoperative dialysis | 0.5% | 3.0% | <0.001 |
| Impaired sensorium | 1% | 1.5% | 0.131 |
| Hemiplegia | 0.5% | 3.0% | <0.001 |
| Paraplegia | 5.3% | 9.0% | 0.009 |
| Quadraplegia | 0.7% | 3.0% | 0.002 |
| History of transient ischemic attack | 1.9% | 0% | 0.003 |
| Cerebral vascular accident /stroke with neurological deficit | 1.7% | 1.5% | 0.971 |
| Tumor involving central nervous system | 1.4% | 4.5% | <0.001 |
| Disseminated cancer | 2.6% | 3.0% | 0.016 |
| Open wound/wound infection | 1.2% | 1.4% | 0.016 |
| Steroid use for chronic infection | 5.1% | 5.7% | 0.057 |
| >10% Loss body weight in past 6 mo | 1% | 0.9% | 0.111 |
| Bleeding disorders | 2.3% | 5.1% | <0.001 |
| Transfusion <72 h before surgery | 2% | 0.8% | 0.002 |
| Chemotherapy ≤30 d before surgery | 1.0% | 3.0% | 0.001 |
| Radiotherapy in past 90 d | 0.5% | 0% | 0.3 |
| Prior operation within 30 d | 8.7% | 13.6% | 0.002 |
| American Society of Anesthesiologists classification | 0.641 | ||
| 1—No disturbance | 1.9% | 3.1% | |
| 2—Mild disturbance | 36.9% | 40.0% | |
| 3—Severe disturbance | 57.4% | 53.5% | |
| 4—Life-threatening disturbance | 3.7% | 3.3% | |
Note: Boldface indicates statistical significance at P < 0.05 across complication levels.