Life‐threatening hyperkalaemia during general anaesthesia in a domestic short‐haired cat

Abstract

There are an increasing number of reports describing the development of hyperkalaemia in healthy veterinary patients during general anaesthesia. While the majority of cases are dogs, it has also been described in large non-domestic cats under general anaesthesia. To the authors’ knowledge, there are no reported cases of acute hyperkalaemia in healthy domestic cats associated with anaesthesia. This case report describes the development of hyperkalaemia in a nine-year-old domestic short-haired cat, anaesthetised for fracture repair. Hyperkalaemia (8.0 mmol/l) was recognised due to the sudden development of bradycardia, spiked T waves, decreased amplitude of P waves, progressing to atrial standstill on the ECG. Initial treatment was with calcium gluconate, insulin and glucose, which resolved the problem, but the hyperkalaemia recurred during recovery from anaesthesia, necessitating further treatment. Possible causes of the hyperkalaemia are discussed.

Hyperkalaemia during two consecutive anaesthetics in an aggressive Bengal cat

“…In this case report, hyperkalaemia was recognised 150 minutes after induction in the first anaesthetic. In a previously reported case in a domestic cat that was anaesthetised with a similar anaesthetic protocol, an increase in plasma potassium occurred after 115 minutes of general anaesthesia 24 . However, in both cases, potassium was only measured following identification of ECG abnormalities.…”

“…However, the phenomenon has not been reported to the same extent in domestic cats. Some studies report hyperkalaemia in cats is triggered by a genetic predisposition to rhabdomyolysis 25 and MH, 26–28 but only one case of hyperkalaemia associated with anaesthesia in a healthy cat has been described 24 . Bengal cats have been selected by breeding domestic cats, particularly the spotted Egyptian Mau, with the Asian leopard cat.…”

“…In a previously reported case in a domestic cat that was anaesthetised with a similar anaesthetic protocol, an increase in plasma potassium occurred after 115 minutes of general anaesthesia. 24 However, in both cases, potassium was only measured following identi-fication of ECG abnormalities. During the second anaesthetic in the case report described here, potassium levels were elevated after 80 minutes.…”

“…Some studies report hyperkalaemia in cats is triggered by a genetic predisposition to rhabdomyolysis 25 and MH, [26][27][28] but only one case of hyperkalaemia associated with anaesthesia in a healthy cat has been described. 24 Bengal cats have been selected by breeding domestic cats, particularly the spotted Egyptian Mau, with the Asian leopard cat. For a Bengal cat to be considered domesticated it must be at least four generations or more from the Asian leopard cat.…”

“…Several cases are reported in dogs, [7][8][9][10][11][12] non-domestic large felids [13][14][15][16][17][18] and horses. [19][20][21][22][23] Unexpected hyperkalaemia in a domestic cat during general anaesthesia has been recently reported, 24 and in other cats in which the cause has been attributed to hyperacute rhabdomyolysis 25 and malignant hyperthermia (MH). [26][27][28] The increasing number of cases described may reflect the frequency of this phenomenon, which is still believed to be under-reported in veterinary medicine.…”