Table 1 Risk factors recorded before ICU admission and during ICU stay

Surgery before ICU admission

Divided into urgent or elective

Diabetes mellitus

Only insulin-treated patients

COPD

Defined as the presence of a productive cough or expectoration for more than 90 days per year (but on separate days) and for more than 2 consecutive years, provided that a specific disorder responsible for these symptoms was not present

Chronic liver disease

With confirmation of the diagnosis by liver biopsy or in patients with signs of portal hypertension, such as oesophageal varices or ascites

Renal failure

Defined as need for haemodyalisis or peritoneal dialysis at the time of admission to the hospital

Severe heart failure

Defined as New York Heart Association functional class III or IV heart failure

Malignancy

Histological evidence required for a diagnosis of solid tumour and definitive diagnosis for the diagnosis of haematological malignancy

HIV infection

Defined as HIV-positive status

Neutropenia

Total leucocyte count ≤ 500/mm³

Immunosuppression

Altered immune status according to APACHE II criteria [8] or in case of a previous diagnosis (congenital or acquired)

Transplant recipients

Those patients receiving solid organ or bone marrow transplant

Chemotherapy

Use of cytotoxic agents for the treatment of a neoplasm or an autoimmune disease within 30 days before ICU admission

Radiotherapy

Radiation therapy within 30 days before ICU admission

During ICU stay

Presence and duration of catheters

Urinary bladder, venous, or arterial catheter

Nutrition

Enteral or parenteral nutrition

Mechanical ventilation

Dialysis

Use of steroids

Patients treated with a daily dose equivalent to 20 mg prednisone

Neutropenia

Total leucocyte count ≤ 500/mm³

Drug use

Antimicrobial and antifungal agents