hemodynamic assessment & useful guidance. In relation to the CVP and the volume of blood in circulation, inferior vena cava (IVC) is a sizable vein with a certain size and form. Septic shock is defined as sepsis accompanied by hypotension that does not respond to fluid resuscitation. Aim: Identifying the link between the diameters of IVC, CVP, as well as Inferior Vena Cava Diameter Collapsibility Index (IVCCI), all while assessing the volume status of critically septic shocked individuals to establish a diagnosis of septic shock. Patient and methods: This prospective observational research involved one hundred individuals who suffered from septic shock & were hospitalized to emergency department at Mansoura University, Mansoura, Egypt. The research was carried out over the course of a single calendar year, beginning on May 20, 2022, and ending on May 20, 2023. Results: There was a considerable disparity among both groups regarding age, sequential organ failure assessment (SOFA) score, heart rate, platelets count, serum urea and serum creatinine, C-reactive protein, ESR, serum lactate, PH, serum bicarbonate, inferior vena cava diameter collapsibility index (IVCCI), systolic blood pressure (SBP) & diastolic blood pressure (DBP). Besides, there was no statistically significant variance between both groups regarding sex, the change in the CVP, initial SBP, DBP, respiratory rate (RR) and temperature. Conclusion: The assessment of CVP as well as IVCCI is an excellent prognostic method in sepsis patients.