Measurement of Anterior–Posterior Diameter of Ivc By Ultrasonography: a Non Invasive Method for Estimation of Central Venous Pressure

The assessment of intravascular volume in severely traumatized patients or patients admitted in ICU is very essential. At present the accurate method for estimating the intravascular volume requirement is by measuring the CVP which is an invasive method. The measurement of IVC diameter by ultrasound has been suggested as an easily available and simple method for measuring the intravascular volume status. The purpose of this study was to compare the results of IVC diameter measurement by ultrasonography and CVP measurement for calculating the intravascular volume in ICU admitted patients.

This was a descriptive and prospective study including 50 patients admitted in ICU with a central venous catheter placed for any reason whatsoever and no signs of increased right atrial pressure. CVP was measured in supine position by CVP manometer. The anterior- posterior IVC diameter was assessed by ultrasonography during inspiration and expiration. Data analysis was performed by SPSS and evaluated statistically with Pearsons regression and linear correlation test.

The mean CVP at inspiration and during expiration was 11.35+ 5.53, 12.20 + 5.65 cmH2O, respectively. The mean of inspiratory and expiratory IVC diameter was 7.71 + 3.5 , 11.37 + 3.28 mm, respectively. There was significant correlation between CVP and IVC diameter both during inspiration (r= 0.64 , p-value= 0.001) and expiration (r=0.495 , p-value=0.001)

The result of this study suggests that IVC diameter measurement by ultrasound can be used as a reliable and non- invasive method for estimating the intravascular volume.