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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