Malicious poisoning of a canine with the neuromuscular blocking agent Rocuronium: A case report with postmortem quantitation

Rocuronium bromide is a non-depolarizing neuromuscular blocking agent (NMBA) commonly used in anesthesia for its rapid onset and intermediate duration of action. While its therapeutic use has been well-documented in humans and experimentally in dogs, this report describes the first known case of its malicious use in the fatal intoxication of a canine. Herein we describe the case of a six-year-old male Plott Hound found deceased under suspicious circumstances. Postmortem investigation revealed focal hemorrhages near potential injection sites and toxicological analysis via liquid chromatography-tandem mass spectrometry (LC-MS/MS) confirmed the presence of rocuronium in muscle tissue, heart blood and urine. The dog had no surgical history or indication for anesthesia. However, rocuronium concentrations mirrored those seen in anesthetized human patients under ventilatory support. The owner, a licensed pharmacist, was suspected of drug theft and aggravated animal abuse. This case highlights the lethality of NMBA's when misused outside of the clinical setting and further underscores a collaborative, multi-institutional, multidisciplinary approach to veterinary forensic investigations.