Comparison Between Using Cardiometry and IVC Collapsibility

Predicting fluid responsiveness in critically ill patients is crucial to optimizing fluid therapy. Traditional static measures like central venous pressure (CVP) are unreliable, while dynamic indices such as stroke volume variation (SVV) and pulse pressure variation (PPV) are considered more accurate but limited to specific conditions. Novel, non-invasive tools for predicting fluid responsiveness are particularly valuable in heterogeneous patient populations, including those with spontaneous breathing or arrhythmias.

Non-invasive cardiometry, utilizing advanced hemodynamic monitoring technologies, offers another method to assess fluid responsiveness. By measuring parameters such as stroke volume and cardiac output, non-invasive cardiometry provides real-time insights into a patient's hemodynamic status without the need for invasive procedures. This approach has the potential to guide fluid management effectively, especially in critically ill patients where invasive monitoring may pose additional risks.

Electrical cardiometry (EC) was introduced as a new bio impedance method with the new algorithm for processing the impedance signal to overcome the limitations associated with bio impedance which are used to measure and calculate hemodynamic parameters as cardiac output, cardiac index, SV and systemic vascular resistance index.

Inclusion criteria

• Patients Diagnosed with Hypotensive Sepsis: Patients must meet the clinical criteria for sepsis according to the Sepsis-3 definitions, including evidence of infection and hypotension despite adequate fluid resuscitation. Hypotension is defined as systolic blood pressure <90 mmHg or mean arterial pressure (MAP) <65 mmHg.
• BMI ≥18.5 and ≤40 kg/m²: Patients will be included regardless of BMI, as long as it falls within the normal to overweight/obese range. Extremes of BMI (e.g., <18.5 or >40) may be excluded due to the potential influence on peripheral perfusion measurements.
• American Society of Anesthesiologists (ASA) Physical Status Classification as:

ASA Score I-III: Patients with an ASA physical status score of I (healthy patients), II (mild systemic disease), or III (severe systemic disease) will be included. Patients with ASA IV or V (those with severe systemic disease that is a constant threat to life) will be excluded due to potential confounding factors.

Exclusion criteria

• Cardiac Conditions: Significant valvular heart diseases, such as severe mitral or aortic regurgitation, which can affect hemodynamic assessments.

Presence of major cardiac arrhythmias, including atrial fibrillation or frequent ectopic beats, as these can interfere with accurate measurement of fluid responsiveness.

• Renal Considerations: Patients undergoing renal replacement therapy or those with end-stage renal disease, as fluid balance and responsiveness may be altered.

• Pregnancy Hemodynamic changes during pregnancy (e.g., increased cardiac output and altered vascular resistance) differ significantly from septic shock.
• Patients with a body mass index (BMI) greater than 40 kg/m² Obesity can affect the accuracy of non-invasive monitoring techniques with poor window.