Hemodynamic Monitoring Using Echocardiography in Shock

Abstract

Hemodynamic monitoring is necessary in unstable patients with shock, especially in the presence of complex circulatory compromise, high risk of rapid worsening or treatment intolerance. It allows early identification of the main mechanisms leading to shock states, hence helps in guiding adequate and targeted therapeutic interventions, and assesses both the efficacy and tolerance of therapy. Critical care echocardiography is currently recommended as the first-line technique for the hemodynamic assessment of patients presenting with acute circulatory failure. Two complementary approaches may be used. Conventional transthoracic echocardiography is primarily performed and may be completed by the transesophageal approach in the presence of suboptimal imaging quality or if expected diagnostic accuracy is deemed insufficient. If a dedicated training in which modalities have recently been detailed is respected, critical care echocardiography is ideally suited to best determine the type of shock and guide its therapeutic management. Importantly, critical care echocardiography provides additional information when compared with the standard management of patients with septic shock, and this accurately identifies the presence of acute cor pulmonale associated with the acute respiratory distress syndrome and depicts potential sources of imprecision of “blind” hemodynamic monitoring devices, such as the transpulmonary thermodilution. Repeated echocardiographic assessment allows monitoring of both the efficacy an tolerance of therapeutic interventions, including the potential deleterious effects of ventilator settings on right ventricular function in patients sustaining moderate-to-severe acute respiratory distress syndrome. In the near future, the emergence of miniaturized transesophageal echocardiographic probes promises to provide adequate tools for prolonged hemodynamic monitoring using critical care echocardiography in the most unstable patients.