The Most Useful Method To Evaluate The Volume Status Of Critical Patients In The Emergency And Intensive Care Units: Point Of Care Ultrasound

Abstract

Background: Accurate and rapid assessment of intravascular volume status of the patients in emergency services and intensive care units at diagnosis, treatment and follow-up stages is crucial yet rather difficult. The purpose of hemodynamic monitoring is to determine cardiovascular insufficiency and to provide the most suitable treatment for unstable patients in critical condition.
 Aim: The study aims to compare vena cava inferior diameter, vena cava inferior- collapsibility index (for spontaneously breathing patients) and vena cava inferior- distensibility index (for patients breathing on mechanical ventilation support) measurement by ultrasonography to central venous pressure measurement by placing invasive catheter for assessment of the intravascular volume status and making an accurate volume replacement in emergency service and intensive care units and to determine the correlation between them.
 Material and Methods: The study was carried out prospectively on the patients above the age of 18 who applied to the emergency service clinic between the dates of 01.06.2014 and 01.04.2015 or who stayed in the emergency intensive care unit between these dates. Measurements were taken from vena cava inferior in both the inspirium and expirium phases by using M mode and they were recorded in millimeter. Simultaneous central venous pressure measurements were performed on the patients by using manometric devices and the results were recorded in cm H2O.
 Results: 43.3% of the patients were female (n: 26) and 56.7% were male (n: 34), and the mean age is 70.58 ± 14.86. The study found high degree of positive correlation between central venous pressure and vena cava inferior diameters and high degree of negative correlation between vena cava inferior- collapsibility index . The study also found that there is a high degree of negative correlation between vena cava inferior- distensibility index and central venous pressure in patients receiving mechanical ventilatory support.
 Conclusion: Measurement of respiratory variation in vena cava inferior diameter by using ultrasonography is a quick, reliable, easily applicable, cost-efficient and non-invasive method in critical patients receiving mechanical ventilatory support or have spontaneous respiration in emergency services and intensive care units and it can be useful in assessing the volume status and estimating central venous pressure.