Clavien-Dindo classification of complications31
| Grade | Definition |
| I | Any deviation from the normal postoperative course without the need for pharmacological treatment or surgical, endoscopic and radiological interventions. Allowed therapeutic regimes are as follows: drugs as antiemetics, antipyretics, analgesics, diuretics, electrolytes, parenteral nutrition and physiotherapy. This grade also includes wound infections opened at the bedside |
| II | Requiring pharmacological treatment with drugs other than such allowed for grade I complications. Blood transfusions are also included |
| III | Requiring surgical, endoscopic or radiological intervention |
| IIIa | Intervention not under general anaesthesia |
| IIIb | Intervention under general anaesthesia |
| IV | Life-threatening complication requiring ICU management |
| IVa | Single organ dysfunction (including dialysis) |
| IVb | Multiorgan dysfunction |
| V | Death of a patient |