Dobutamine-Induced Perioperative Anaphylaxis in a Dog

A 9-years old spayed female Maltese was referred for the treatment of mass on the right 1^st mammary gland and acute weight bearing lameness of right hindlimb. It was diagnosed as malignant mammary tumor and cranial cruciate ligament rupture of right stifle joint. Right upper regional mastectomy followed by cranial closing wedge osteotomy (CCWO) of the right tibia were planned for the present problems. Preanesthetic work-up did not show any remarkable abnormalities. Forty-five minutes after induction of anesthesia dobutamine was administered at a rate of 5 ㎍/kg/min by constant rate infusion due to gradual decrease of blood pressure below MAP 60 mmHg during surgical procedure. Despite of the increase of dobutamine infusion rate up to 20 ㎍/kg/min, blood pressure didn't recover. At the end of regional mastectomy generalized skin redness and eyelid edema were identified. Anesthesia was stopped and CCWO procedure was cancelled. To recover from the anaphylactic reactions dexamethasone and diphenhydramine were administered. After about one hour, the patient completely recovered from hypotension and anaphylactic reactions. After 4 weeks, intradermal skin test (IDST) was performed for all the drugs used during anesthesia. Only dobutamine showed positive reaction in IDST. Therefore, dobutamine was considered as the causative agent of anaphylaxis in this patient during the anesthesia. In case of perioperative anaphylactic reaction, postoperative investigation should be performed to identify causative agent and to provide safe recommendations for future anesthetic procedure.