Prospective Comparative study of Ultrasound Guided Central Venous Pressure Measurement using Jugular Vein and Inferior Venacava Diameters for Postoperative Patients on Mechanical Ventilation

INTRODUCTION: Physical examination of Jugular Venous Pressure is always considered as an integral part of the cardio vascular system examination and precise bedside Jugular Venous Pressure analysis is highly desirable. Jugular Venous Pressure is important for estimation of cardiac filling pressures and it can be reliably estimated in the bedside. Hemodynamic monitoring in the form of invasive arterial, central venous pressure and PCWP monitoring is frequently required in critically ill surgical and medical ICU patients. Also it is of utmost value in patients undergoing cardiac surgeries and surgeries involving gross hemodynamic changes. OBJECTIVE: The aim of the study was to evaluate the correlation between the sonographically measured Central Venous Pressure and conventionally measured invasive Central Venous Pressure in postoperative patients on mechanical ventilation. METHODS: Ultrasonography was performed on 50 post operative patients on mechanical ventilation for estimating Central Venous Pressure. The Internal Jugular Vein (IJV) and Inferior Vena Cava (IVC) diameters were measured during the respiratory cycle and the IJVarea and IVC index were calculated. The study was conducted in the Post Anesthesia Care Unit of our hospital. RESULTS: A CVP of 10 mm Hg was selected as clinically significant cutoff for high CVP and 6 mm Hg was chosen for low CVP. According to our study, a strong positive correlation was found between the invasive CVP and IJV max (Maximum Internal Jugular Vein diameter), IJV min (Minimum Internal Jugular Vein diameter), IJVarea (Internal Jugular Vein area), IVC max (Maximum Inferior Vena Cava diameter), IVCmin (Minimum Inferior Vena Cava diameter), with a Pearson's “r” value of 0.904495; 0.918336 ; 0.939898 ; 0.89597; 0.924532 ; respectively. A strong negative correlation was found between invasive CVP and IVC-Collapsibility Index. (Pearson's "r" value=-0.92307). There was no significant correlation between invasive CVP and age, sex or BMI as per our study. CONCLUSION: From the study, we conclude that in postoperative patients on mechanical ventilation, the sonographically estimated Central Venous Pressure helps in the assessment of intravascular volume status. The response to fluid resuscitation can be evaluated by this method. This is a non invasive without any complications