FAILURE OF HYPERINSULINEMIC-EUGLYCEMIA IN CALCIUM CHANNEL BLOCKER OVERDOSE

Abstract

SESSION TITLE: Wednesday Medical Student/Resident Case Report Posters SESSION TYPE: Med Student/Res Case Rep Postr PRESENTED ON: 10/23/2019 09:45 AM - 10:45 AM INTRODUCTION: There is a growing body of evidence to support hyperinsulinemic-euglycemia for calcium-channel blocker overdose. However, when given in lower doses than the recommended protocol, hyperinsulinemic-euglycemia was shown to be ineffective in maintaining adequate blood pressure. CASE PRESENTATION: 56-year-old female with hypertension, depression, and a previous suicide attempt admitted to the ICU for an intentional drug overdose with 105 mg of amlodipine. She was hypotensive in the ED despite fluid resuscitation and required pressor support with norepinephrine and phenylephrine. Poison Control recommended starting hyperinsulinemic-euglycemia. She was started on only 0.5u/kg short-acting insulin bolus, followed by a short-acting insulin drip starting at 0.5u/kg/hr. She required multiple doses of glucose and potassium supplementation, showed no marked increase in BP, and continued to require pressor support for the next 48 hours which is approximately the half-life of amlodipine. DISCUSSION: There has been a growing evidence supporting hyperinsulinemic-euglycemia for calcium-channel blocker overdose with improved survival compared to epinephrine [1]. Evidence has been mostly noted in case reports and animal models [2]. The mechanism by which hyperinsulinemic-euglycemia works is still poorly understood, although there is a theory that calcium-channel blockers cause insulin-resistance in the myocardium that is overcome by high-doses insulin [3]. The recommended dose of high-dose insulin therapy by poison control, and in literature, is 1u/kg bolus followed by 0.5u/kg/hr drip to be titrated up to a max of 10u/kg/hr with an end-goal of improvement of hypotension [1]. In the case of our patient, concern over hypoglycemia and hypokalemia, the patient was started with only 0.5u/kg bolus, followed by 0.5u/kg/hr drip that was only titrated up to 0.7u/kg/hr. At this rate, high dose insulin therapy was ineffective in maintaining adequate BP in our patient. CONCLUSIONS: As proven by previous studies, a full 1u/kg bolus must be given to calcium channel blocker overdose patients in order to show any measurable effect on blood pressure. Concern for hypoglycemia and hypokalemia should not prevent clinicians from administering the full dose. Reference #1: Boyer EW, Shannon M. Treatment of calcium-channel-blocker intoxication with insulin infusion. N Engl J Med. 2001 May 31;344(22):1721-2. PubMed PMID: 11386285. Reference #2: Kline JA, Tomaszewski CA, Schroeder JD, Raymond RM. Insulin is a superior antidote for cardiovascular toxicity induced by verapamil in the anesthetized canine. J Pharmacol Exp Ther. 1993 Nov;267(2):744-50. PubMed PMID: 8246150. Reference #3: Kline JA, Raymond RM, Schroeder JD, Watts JA. The diabetogenic effects of acute verapamil poisoning. Toxicol Appl Pharmacol. 1997 Aug;145(2):357-62. PubMed PMID: 9266809. DISCLOSURES: No relevant relationships by Charles Hildebrand, source=Web Response No relevant relationships by Samer Ibrahim, source=Web Response No relevant relationships by Howard Sklarek, source=Web Response