Summary of risk scores
| ASA | Revised cardiac risk index | Thoracic revised cardiac risk index | ARISCAT risk index | ||||
| Risk factors | Points | Risk factors | Points | Risk factors | Points | Risk factors | Points |
| ASA I | 0 | History of coronary artery disease | 1 | History of coronary artery disease | 1.5 | Age: 51–80 years / >80 years | 3 / 16 |
| ASA II | 2 | Respiratory infection in the past month | 17 | ||||
| ASA III | 4 | History of heart failure | 1 | History of cerebrovascular disease | 1.5 | ||
| ASA IV | 5 | History of cerebrovascular disease | 1 | Surgical incision: upper abdominal / intrathoracic | 15 / 24 | ||
| ASA V | 6 | Pneumonectomy | 1.5 | ||||
| Surgical risk: low / intermediate / high / emergency intervention | 0 / 1 / 2 / 1 | High-risk surgery (vascular, intraperitoneal or intrathoracic) | 1 | Serum creatinine >177 μmol·L−1 | 1 | Emergency procedure | 8 |
| Preoperative SpO2: 91–95% / ≤90% | 8 / 24 | ||||||
| Preoperative insulin therapy | 1 | Preoperative anaemia (≤10 g·dL−1) | 11 | ||||
| Serum creatinine >177 μmol·L-1 | 1 | Duration of surgery: >2–3 h / >3 h | 16 / 23 | ||||
ASA: American Society of Anesthesiologists’ classification of physical health; ARISCAT: Assess Respiratory Risk in Surgical Patients in Catalonia; SpO2: arterial oxygen saturation measured by pulse oximetry.