Conclusion
In the cat reported here, a notable response to HIET was appreciated as evidenced by an increase in temperature, heart rate, blood pressure and contractility within 15 minutes of initiating therapy. The dosing recommendation for animals is a 1 U/kg insulin bolus followed by a 1U/kg/h CRI for 1 hour, followed by 0.5 U/kg/hr until resolution of clinical signs10 . There is no set protocol for timing of discontinuation of HIET, however the goal of therapy is hemodynamic stability. Based on previous reports and human guidelines, prolonged therapy may be needed. The primary complications associated with HIET are hypoglycemia and hypokalemia; both of which can be anticipated, monitored and addressed. The initiation of vasopressor therapy in the context of amlodipine toxicosis should be approached with caution and considered after initiation and optimization of HIET. The authors also recommend monitoring of magnesium and phosphorus, which have a complex interplay with insulin and are vital for myocardial cellular activity. The wide availability of insulin and dextrose, low expense, and minimal adverse event profile make HIET an attractive therapeutic option for CCB toxicosis. Although the outcome was unsatisfactory in this case, the authors feel that the response to HIET supports the use of this therapy in cats with CCB toxicosis.
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