Suspected anaphylaxis from intravenous cefazolin during general anaesthesia in a dog

Abstract

A 6-year-old female Shetland Sheepdog with a history of cardiorespiratory compromise during general anaesthesia was referred for ovariohysterectomy surgery. Clinical examination was unremarkable at presentation and physiologic parameters under general anaesthesia were within expected ranges during preparation for surgery. Shortly after completion of an intravenous injection of cefazolin, the audible signal from the Doppler ultrasound unit stopped. A rapid survey of the patient revealed tachycardia with weak femoral pulses, tachypnoea, hyperpnoea and substantially increased resistance to manual positive pressure ventilation. Stopping inhalant anaesthesia, administering salbutamol, corticosteroids and diphenhydramine were associated with resolution of clinical signs. However, marked hypotension and resistance to ventilation recurred approximately 25 minutes later. Low dose intravenous epinephrine (5 mcg/kg) was effective at increasing arterial blood pressure and reversing respiratory dysfunction. Surgery was completed and the patient recovered uneventfully. Initial reliance on second line therapy and delay in administering epinephrine, the recommended treatment for anaphylaxis, may have slowed resolution of clinical signs.

A suspected non‐allergic anaphylactic reaction to intravenous administration of atracurium in a dog

“…We decided not to administer epinephrine because cardiovascular signs were moderate and were improving in our patient. Furthermore, unlike various other case reports in the veterinary literature 18,23,26,29,30 where respiratory signs (bronchospasm and decreased chest compliance) were associated with cardiovascular ones, no signs of severe bronchoconstriction were evident in our patient (Tv and PIP did not show any changes during the episode). Nonetheless, peripheral pulses were still weak 15 minutes after the onset of hypotension.…”

“…Cases of hypersensitivity reaction following atracurium administration are well documented in human medicine, 9,11,20–22 but no reports exist in veterinary medicine. Numerous other drugs administered in the perioperative period can be responsible for an acute non‐allergic hypersensitivity reaction or allergic anaphylaxis, among which antibiotics, 23–26 opioids, 27,28 iodinated 29 and gadolinium‐based contrast media, 8,30 thiopentone, 31–33 acepromazine, 34,35 dexamethasone, 36 xylazine‐ketamine 37 and rocuronium, 18 just to mention a few. Particularly during the perioperative period, many of these drugs are likely to be administered concurrently, thus making it difficult for the clinician to identify the agent responsible for the adverse reaction.…”