Table 1 Pulmonary complication grading scheme adapted from the Clavien-Dindo classification (Dindo et al. 2004)

Grade I

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

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

Secretion retention requiring physiotherapy

Atelectasis requiring physiotherapy

Therapeutic supplemental oxygen given by nasal catheter or oxygen mask

Grade II

Requiring pharmacological treatment with drugs other than such allowed for grade I complications

Blood transfusions and total parenteral nutrition are also included

Pneumonia treated with antibiotics on the ward

Grade III

Requiring surgical, endoscopic, or radiological intervention

Suction of secretions by bronchoscopy for treatment of pneumonia

Atelectasis requiring bronchoscopic intervention

Grade IIIa

Intervention not under general anesthesia

Grade IIIb

Intervention under general anesthesia

Grade IV

Life-threatening complication requiring IC/ICU management

Readmission to the ICU because of respiratory dysfunction

Grade IVa

Single organ dysfunction (including dialysis)

Respiratory failure requiring endotracheal or noninvasive ventilation

Grade IVb

Multiorgan dysfunction

Respiratory failure with failure of another organ

Grade V

Death of a patient

Death