Non-Invasive Cardiometry and Ultrasound Guided Inferior Vena Cava Collapsibility Index in Assessing Fluid Responsiveness
Condition: Volume Overload; Tissue Perfusion
Study type: Interventional

Summary: 
      43 patients between 18-60 years presenting with criteria of sepsis (life-threatening organ
      dysfunction caused by a dysregulated host response to infection, suspected or documented
      infection and an acute increase ≥2 SOFA [Sequential Organ Failure Assessment] points) will be
      enrolled in our study. Approval of the ethical committee and informed written consent from
      first degree relatives will be issued. They will be given a full and detailed explanation of
      the intended study protocol and will be informed about the potential benefits of the
      development of a successful technique as well as the potential side-effects.

      To compare the efficacy of non-invasive cardiometry and ultrasound (US) guided inferior vena
      cava (IVC) collapsibility when assessing the response of septic patients to fluid therapy
      guidelines of The Third International Consensus Definitions for Sepsis and Septic Shock
      (Sepsis-3); in the first six hours of ICU admission .
    

Detailed description: 
      One of the newer non-invasive methods used to assess fluid status has been the IVC
      collapsibility index (IVC CI) - which has shown encouraging results as a guide to fluid
      therapy. Studies have shown that there is an increase in CVP and decrease in IVC
      collapsibility with fluid replacement, as well as that both are affected by changes in
      intrathoracic pressure and right heart dysfunction.

      measurement of (IVC CI) is calculated by ultrasound through maximum IVC diameter - minimum
      IVC diameter divided by minimum diameter then multiplied by 100.

      if it is less than 50% means that the patient is volume non- depleted while if it is more
      than 50% means the reverse.

      The other recent non-invasive monitoring tool is electrical cardiometry. Its idea is based on
      electrical impedance. The variations in impedance are calculated using an algorithm that
      allows measurement of the CO as well as other key haemodynamic parameters including preload
      (Thoracic Fluid Index), afterload (systemic vascular resistance, SVR). This has helped
      provide a sound guide to each individual patient's response to fluid therapy and selection of
      the proper cardiovascular medications and support.

      To compare the efficacy of non-invasive cardiometry and ultrasound (US) guided inferior vena
      cava (IVC) collapsibility when assessing the response of septic patients to fluid therapy
      guidelines of The Third International Consensus Definitions for Sepsis and Septic Shock
      (Sepsis-3); in the first six hours of ICU admission .
    

Intervention name(s): OSYPKA Medical ICONTM Noninvasive CardiometerTM Model C3; Fujifilm Sonosite M-Turbo C Ultrasound system
Intervention type(s): Device; Device
Intervention description(s): Based on its precedent electrical impedance. 4 electrodes are placed on the patient: 2 on the left of the neck and the other 2 on the left lower chest . A low magnitude (2 mA), high frequency (30-100 KHz) alternating electrical current (AC) of constant amplitude is applied through the outer electrodes, and the resulting voltage is received by the inner electrodes. The ratio of the detected voltage to the applied current is the bio-impedance. The principle on which this is based is that during systole, red blood cells flow in a parallel manner, which allows the electrical current to flow easily thereby improving the electrical velocity and decreasing impedance. While during diastole, RBCs are randomly arranged, consequently hindering the electrical current (increased impedance) and decreasing electrical velocimetry. The changes of impedance over time are integrated in a complex algorithm that allows to measure CO and the other parameters.; A low-frequency phased array transducer (3.5-5 MHz) will be used to assess the IVC, which lies in the retroperitoneum, to the right of aorta. At or near the junction with the hepatic veins, we will measure the IVC diameter. To properly visualise the IVC, the probe will be inserted in the subxiphoid 4-chamber position with the probe marker oriented vertically to find the right ventricle and atrium. We will see the convergence of the IVC with the right atrium as the probe is progressively aimed towards the spine. We will then follow the IVC inferiorly, to detect the meeting of the hepatic veins with the IVC. M-mode Doppler sonography of the IVC will be used to graphically document the absolute size and dynamic changes in the calibre of the vessel during inspiration and expiration. After the visualisation of the IVC, we will freeze the US screen, and using the caliper function on the US machine, maximum and minimum diameters of the IVC will be documented.
Other intervention name(s): Non-invasive cardiometry; Inferior Vena Cava Collapsibility Index
Intervention model: Single Group Assignment
Masking: None (Open Label)
Primary purpose: Diagnostic
Keywords: Sepsis; IVC; IVC collapsibility index; ICU; Non-invasive cardiometry; Cancer; Critically ill