Thoracic Fluid Content as an Outcome Predictor in Respiratory Intensive Care Unit

Hemodynamic monitoring is measuring and monitoring the factors that influence the force and flow of the blood. It is an important aspect of patients care in operating rooms and critical care units. It aims to guide medical management so as to prevent or treat organ failure and improve the outcomes of patients. This monitoring itself includes several different techniques and may range from invasive to less and even non-invasive techniques.

Critically ill patients are often hemodynamically unstable (or at risk of becoming unstable) owing to hypervolemia, cardiac dysfunction or alterations of vasomotor function, leading to organ dysfunction, deterioration into multi-organ failure and eventually death range from 15% to 25% of patients admitted to intensive care units.

Impedance cardiography (ICG) and Electrical Cardiometry (EC) are recently developed technologies to measure thoracic fluid content (TFC), cardiac output (CO) and other hemodynamic parameters. Both ICG and EC derive CO from measurements of Thoracic Electrical Bioimpedance (TEB).

One of the parameters examined by electrical cardiometry is thoracic fluid content(TFC) ,which is inversely associated with the patient's transthoracic electrical bioimpedance, and reflects the total (intravascular and extravascular) fluid volume contained in the chest cavity. A study concluded that electrical cardiometry monitoring indicated new possibility to anticipate prognosis of pneumonia patient. Increased thoracic fluid content value would relate to worse outcome of the patient like mortality and intensive care unit admission. Electrical cardiometry monitoring allows real-time measurements of thoracic fluid content without restraining the patient or invasive catheters.

In ARDS patients with cardiac comorbidities, TFC can distinguish between non-cardiogenic and cardiogenic pulmonary edema. In addition, TFC is helpful in the differential diagnosis of the mechanisms of respiratory failure. Thus, recently it was shown that TFC was greater in ARDS than in patients with atelectasis or pleural effusion. Therefore, depending on the TFC value, we can provide different therapeutic interventions.