A Suspected Anaphylactoid Reaction to Propofol in a Dog

Anaphylactoid reactions to anaesthetic drugs are rarely reported in veterinary medicine. The aim of this report is to describe a suspected anaphylactic reaction to propofol in a 14 years old Shih-Tzu undergoing general anaesthesia for ovariohysterectomy due to a pyometra. The anesthetic protocol included intramuscular methadone for premedication and fentanyl, midazolam and propofol intravenously for co-induction. At endotracheal intubation, the glottis appeared subjectively thickened. Shortly after induction and endotracheal intubation, desaturation, hypercapnia and bradycardia occurred; chest compliance at manual ventilation was poor and peripheral pulses were weak. The procedure was aborted. Pulmonary oedema was diagnosed at thoracic radiography and a cardiogenic origin was excluded via echocardiography. Fluid therapy and glucocorticoids were administered, and mechanical ventilation was started in the intensive care unit. Two hours later, the owner opted for euthanasia due to financial constraints.