Management of an anaphylactoid crisis due to mast cell degranulation in a dog during general anaesthesia

It is widely stated within the veterinary literature that manipulation of a mast cell tumour can lead to an anaphylactoid reaction; however, there is limited information on the frequency or management of such cases in companion animals. A nine-year-old, 38.4 kg, female neutered, labrador (retriever) presented for excision of a cutaneous mast cell tumour located on the left lower eyelid. This report describes a Grade III anaphylactoid crisis (hypotension, bradycardia and bronchospasm) that occurred when the dog was under general anaesthesia following mast cell degranulation. Prompt management following fluid resuscitation, administration of an aerosolised bronchodilator and intravenous atropine, successfully addressed the underlying pathophysiology of anaphylactoid crisis.