Central Venous Oxygen Saturation Impact on Prognosis of Post Arrest Patients

Central venous oxygen saturation (ScvO₂) is a very important measurement which can be easily taken in a critical care environment by both medical and nursing staff. It provides an understanding of the patient's oxygen delivery, oxygen consumption and cardiac output. It has a key role within early goal-directed therapy and has been shown to decrease mortality when taken and analysed appropriately. (Central venous oxygen saturation: analysis, clinical use and effects on mortality,2013) Venous oxygen saturation (SvO2) measures the blood's oxygen content returning to the right side of the heart after perfusing the entire body. When the oxygen supply is insufficient to meet the metabolic demands of the tissues, an abnormal SvO2 ensues and reflects an inadequacy in systemic oxygenation. SvO2 is, therefore, dependent on oxygen delivery and oxygen extraction. Venous oximetry is used in specific clinical settings of hemodynamic instability, such as in critical illnesses, perioperative periods of major surgeries, heart failure, sepsis andd post arrest patients. The venous blood in the pulmonary artery represents oxygen extraction in the whole body and is called mixed venous oxygen saturation (SmvO2). It was measured using a pulmonary artery catheter (PAC). A second, less invasive method of measuring SvO2 is via a central venous catheter (CVC) positioned in the superior vena cava and is called the central venous oxygen saturation (ScvO2).

Central venous oxygen saturation (ScvO(2)) is suggested to reflect the adequacy of oxygen delivery, and the main objective of the present study was to determine whether ScvO(2) is associated with outcome in haemodynamically stabilized post arrest patients predicting mortality and outcome based on central venous oxygen saturation