A 7-year-old Percheron gelding presented to the Equine Orthopedic Surgery Service at Cornell University treatment for overgrown hooves and chronic hoof abscesses. For 4-years he had resisted hoof trimming and consequently had had very little hoof maintenance. Due to his temperament and size, he was placed under general anesthesia to facilitate hoof trimming and shoe placement. Corrective heart-bar shoes were fabricated and placed on his feet while under intravenous anesthesia. The procedure and anesthetic recovery were without incident. That evening his catheter became detached transiently. He suffered an episode of acute lameness and collapse followed by an obtunded state. He recovered quickly and by I hour after the episode of collapse he had with no apparent neurological deficits. An air embolus was suspected but not confirmed. Intravenous catheters are used commonly in many species, veterinary and human alike. Thrombophlebitis and infection are common complications but other infrequent but equally severe events may occur. Several factors influence the success of intravenous catheters; dwell time, systemic health of the patient, and local catheter environment are some of the most important. Events such as catheter or air embolization are not predictably correlated with those factors. Both human and veterinary medical practitioners have taken preventative steps to reduce the occurrence of these adverse events and to better manage intravenous catheters.