Utility of transpulmonary thermodilution with Pulse Index Continuous Cardiac Output system for hemodynamic assessment in a hemodialysis patient with arteriovenous fistula and continuous renal replacement therapy: A case report

Close hemodynamic monitoring is crucial for the patients to guide cardiovascular therapy for the optimal management. Transpulmonary thermodilution offers a less invasive hemodynamic monitoring with Pulse Index Continuous Cardiac Output system analysis. Intracardiac shunts have been associated with well-defined alterations in transpulmonary thermodilution–related hemodynamic parameters leading to inaccurate measurements and therefore are among the contraindications for transpulmonary thermodilution. However, data on the effects of arteriovenous fistulas as well as extracorporeal circuits on the thermodilution curves remain limited and inconclusive. Herein, we report generation of modified thermodilution curve forms leading to incorrect calculation of thermodilution-derived hemodynamic parameters by Pulse Index Continuous Cardiac Output system in a female patient in the presence of Continuous Veno-Venous Hemodiafiltration and a high flow arteriovenous fistula. Our findings revealed generation of modified thermodilution curves and unacceptably high extravascular lung water readings by Pulse Index Continuous Cardiac Output system. This seems consistent with early recirculation of cold indicator in case of a peripheral shunt emphasizing the potential impact of high flow arteriovenous fistula on reliability of transpulmonary thermodilution measurements in critically ill patients, limiting the use of Pulse Index Continuous Cardiac Output system in these conditions