Effect of Adding Vasopressin on Cardiac Output, Blood Pressure, Diuresis, and Tissue Perfusion Indices in Patients With Septic Shock

In patients with septic shock, vasopressin is increasingly used in combination with norepinephrine, but its timing of initiation remains heterogeneous and its clinical hemodynamic effects are still insufficiently characterized. Available data suggest variable responses, which may depend on the hemodynamic phenotype at the time of treatment initiation. In particular, the effects of vasopressin may differ according to the presence of preload dependency, baseline cardiac output, impaired systolic function, or baseline diastolic arterial pressure, reflecting the degree of vasoplegia. In this context, the VASO-PHENO study aims to provide a detailed and dynamic description of the early hemodynamic and clinical effects of vasopressin initiation in septic shock. To date, no clinical study has systematically and dynamically evaluated the effects of vasopressin on central and peripheral hemodynamic parameters according to the hemodynamic profile at the time of its initiation. Describing these effects appears essential to better understand the variability in clinical responses and to contribute to a more rational and personalized approach to vasopressor escalation in septic shock.