“…Through the use of invasive (ie, pulmonary artery thermodilution catheters) and noninvasive systems (ie, thoracic electrical bioimpedance devices) for continuous monitoring of cardiac output, William Shoemaker and others have helped to more clearly define the patterns of acute circulatory dysfunction in the early shock phase. Intensive monitoring of those patients with critical illness from high‐risk surgery, trauma, and sepsis linked survival to significantly higher cardiac indices (CIs), oxygen delivery (DO 2 ), and oxygen consumption (VO 2 ) when compared with nonsurvivors with the same comorbidities and type of shock 1 , 2 . Thus, these studies suggest that failure to respond to the hemodynamic dysfunction in the early postinjury phase (ie, ebb phase) portends an unfavorable prognosis, including multisystem organ failure and/or death.…”