A Case Report: Tizanidine-Induced Cardiogenic Shock Managed in a U.S. Army Role 3 Field Hospital

We report a 58-year-old Active-Duty male who developed transient, severe left ventricular dysfunction with cardiogenic shock after tizanidine ingestion, successfully managed in a forward-deployed Role 3 U.S. Army Field Hospital. This case highlights the use of multimodal macro- and micro-hemodynamic monitoring-capillary refill time, urine output, lactate, central venous oxygen saturation (ScvO2), and bedside echocardiography-to guide titration of vasoactive medications when right heart/pulmonary artery catheterization was unavailable. Echocardiography was applied both qualitatively (visual ejection fraction assessment) and quantitatively (stroke volume and cardiac output estimation via left-ventricular outflow tract [LVOT] diameter and velocity-time integral [VTI]). Despite profound left ventricular dysfunction and multi-drug hemodynamic dependence, cardiac function quickly normalized. This case demonstrates that advanced, physiology-guided shock resuscitation is feasible in trauma-focused, forward-deployed environments and adds to the sparse literature recognizing tizanidine-induced, reversible heart failure.