Oxygen Consumption (V̇O2)

The goal of this prospective observational study is to analyse change in VO2 and VCO2 measured via a dedicated ventilator after hemodynamic optimization maneuvers in adult patients admitted to the ICU with any sign of shock. The main questions it aims to answer are: 1. Do common maneuvers for hemodynamic optimization (fluid bolus and/or vasopressor administration) have any impact on tissue perfusion in terms of oxygen consumption (VO2) and carbon dioxide production (VCO2) measured by a dedicated ventilator? 2. Are the values measured by exhaled gas comparable to those calculated by the measurement of dissolved veno-arterial gas? Participants enrolled in the study will receive advanced hemodynamic monitoring with MostCare Up (Vygon ®) and their hemodynamic instability will be managed according to most recent guidelines and based on clinical decision of treating physicians.