Intravenous crystal formation around a central venous catheter likely due to incompatibility of thiopental and acidic drugs: a case report

Abstract

Thiopental, a strong base, is known to precipitate when mixed with acidic drugs; thus, administration of thiopental and acidic drugs via separate routes is recommended. Here we present the case of a woman in her 50s with refractory status epilepticus who developed intravascular crystallization after administration of multiple anticonvulsants and sedatives, including thiopental, via a central venous catheter (CVC). On day 40, following an unsuccessful attempt to remove the CVC, computed tomography revealed a high-density intravascular foreign body extending from the left internal jugular vein to the left brachiocephalic vein. The catheter that was later removed showed white solid deposits, and electron microscopy revealed the presence of crystalline components. The patient died of multiple organ failure on day 90. Autopsy revealed gray solid masses, 1-2 cm in size, filling the vessels. Electron microscopy of the solid adhering to the CVC surface confirmed the presence of crystalline components, indicating that the basic drug thiopental (pH 10.2-11.2) had reacted with the acidic drugs midazolam (pH 2.8-3.8) and rocuronium (pH 2.8-3.2), resulting in crystallization.