The therapy used to correct a specific complication is the basis of this classification in order to rank a complication in an objective and reproducible manner.


It consists of 7 grades (I, II, IIIa, IIIb, IVa, IVb and V). The introduction of the subclasses a and b allows a contraction of the classification into 5 grades (I, II, III, IV and V) depending on the size of the population observed or the of the focus of a study.


Complications that have the potential for long-lasting disability after patient’s discharge (e.g.: paralysis of a voice cord after thyroid surgery) are highlighted in the present classification by a suffix (“d” for disability). This suffix indicates that a follow-up is required to comprehensively evaluate the outcome and related long-term quality of life. The classification is presented below.






























The Clavien-Dindo Classification of Surgical Complications

Full Scale

Contracted Form




Grade  I:

Any deviation from the normal postoperative course without the need for pharmacological treatment or surgical, endoscopic and radiological interventions.


Grade  I:

Same as for Full Scale

Allowed therapeutic regimens are: drugs as antiemetics, antipyretics, analgetics, diuretics and electrolytes and physiotherapy. This grade also includes wound infections opened at the bedside.


Grade  II:

Requiring pharmacological treatment with drugs other than such allowed for grade I complications.
Blood transfusions and total parenteral nutrition are also included.

  Grade  II: Same as for Full Scale

Grade  III:

Requiring surgical, endoscopic or radiological intervention


Grade  III:


Grades IIIa & IIIb

     Grade III-a:

intervention not under general anesthesia

     Grade III-b:

intervention under general anesthesia


Grade IV:

Life-threatening complication (including CNS complications)‡ requiring IC/ICU-management

  Grade IV: Grades IVa & IVb

     Grade IV-a:

single organ dysfunction (including dialysis)

     Grade IV-b:

multi organ dysfunction


Grade V:

Death of a patient

  Grade V: Same as for Full Scale

Suffix 'd':

If the patients suffers from a complication at the time of discharge,  the suffix  “d”  (for ‘disability’) is added to the respective grade of complication. This label indicates the need for a follow-up to fully evaluate the complication.



‡ brain hemorrhage, ischemic stroke, subarrachnoidal bleeding,but excluding transient ischemic attacks (TIA);IC: Intermediate care; ICU: Intensive care unit.


Dindo D., Demartines N., Clavien P.A.; Ann Surg. 2004; 244: 931-937