Table 2.

Clavien–Dindo classification of surgical complications

Grade	Definition
I	Any deviation from the normal postoperative course without the need for pharmacological treatment or surgical, endoscopic and radiologic interventions. Allowed therapeutic regimens are drugs including antiemetics, antipyretics, analgesics and diuretics, and electrolytes and physiotherapy. This grade also includes wound infections opened at the bedside.
II	Requiring pharmacological treatment with drugs other than those allowed for grade I complications. Blood transfusions and total parenteral nutrition are also included.
III	Requiring surgical, endoscopic or radiological intervention
IIIa	Intervention not under general anesthesia
IIIb	Intervention under general anesthesia
IV	Life-threatening complication (including CNS complications)1 requiring IC/ICU management
IVa	Single organ dysfunction (including dialysis)
IVb	Multiple organ dysfunction
V	Death as a result of complications

¹Brain hemorrhage, ischemic stroke, or subarachnoid bleeding, but excluding transient ischemic attacks. Adapted from Clavien–Dindo classification. CNS: Central nervous system; IC: Intermediate care; ICU: Intensive care unit.