Personalized Hemodynamic Therapy in Patients Undergoing High-risk Surgery

Inclusion Criteria: * Patients ≥ 18 years undergoing a major abdominal procedure (including general, urological, gynaecological, and vascular) with an expected duration of surgery ≥ 90 min or presumed blood loss exceeding 1,000 mL (e.g., intrabdominal vascular surgery) and ≥ 1 of the following high-risk criteria: * acute or chronic renal impairment (serum creatinine ≥ 1.3 mg/dL) * predefined risk factors for cardiac or respiratory complications * Immunodeficiency due to a therapy (e.g., immunosuppressants, chemotherapy, radiation, long-term or high-dose steroids) * Immunodeficiency due to specific diseases (e.g., leukaemia, lymphoma, AIDS) * severe liver impairment (biopsy proven liver cirrhosis plus 1 of the following: portal hypertension or history of upper gastrointestinal bleeding due to portal hypertension or previous episodes of hepatic insufficiency/hepatic encephalopathy/hepatic coma * Age ≥ 80 years Exclusion Criteria: * Age \<18 years * Pregnancy * surgery for palliative treatment * emergency procedure * refusal of consent * participation in another randomized controlled trial * failure to meet inclusion criteria