Optimum treatment of vasopressor-dependent distributive shock

Abstract

Distributive shock is associated with decreased systemic vascular resistance and altered oxygen extraction. Septic shock is the most frequent form of distributive shock. In shock states, duration of hypotension is associated with poor outcomes. The speed at which treatment to restore adequate perfusion pressure is initiated is, therefore, important to improve survival. Areas covered: This review presents an overview of the literature related to the management of vasopressor-dependent distributive shock, and in particular the relationship between arterial pressure and organ perfusion and function. Studies that have tried to determine an optimal blood pressure level are discussed demonstrating that it is difficult to define and will vary according to individual patient factors, including age and a history of chronic hypertension. An initial target mean arterial pressure (MAP) of 65-70 mmHg is probably sufficient in most patients. The influence of increasing MAP on the microcirculation is also covered. Expert commentary: Microcirculatory monitoring may be the best way to individualize management of these patients, but remains experimental at present. In the meantime, repeated blood lactate levels and venous oxygen saturations, combined with hemodynamic variables and the clinical picture, can provide an indication of the response to treatment and adequacy of tissue perfusion.

Keywords: Sepsis; cellular metabolism; oxygen delivery; systemic vascular resistance; vasoactive agents; vasoconstriction; vasodilation.