Evaluation of Hemodynamics and Amount of Blood Flowing Through the Kidneys by Measuring Some Physiological Substances in Blood and Urines

Hemodynamic Indexes and Renal Perfusion: Indirect Evaluation of Blood Volume Using the Association Between ScvO2 and Urinary Electrolytes in Patients Undergoing Major Surgery.

The purpose of this study is to verify any existing relationship between mixed oxygen saturation (from central venous catheter) and urinary sodium, potassium, chloride in determining the volemic state and renal perfusion of patients undergoing major surgical interventions.

Inclusion Criteria:

• thoracic-abdominal major surgical operations
• placing of a central venous catheter and urinary catheter
• age 18-75
• ASA class I-III

Exclusion Criteria:

• age above 75 or under 18
• ASA class IV
• trauma, sepsis and/or heart-lung failure
• liver transplantation
• kidney transplantation
• pre-existing renal failure
• pregnant patients
• patients unable to give their written consent