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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Acute Disease, Adrenergic beta-Agonists, Adrenergic beta-Antagonists, Animals, Antidotes, Disease Models, Animal, Dogs, Drug Evaluation, Preclinical, Drug Monitoring, Epinephrine, Glucagon, Hemodynamics, Hypoglycemic Agents, Insulin, Poisoning, Propranolol, Survival Analysis.
user
Does insulin improve survival in a canine model of acute beta-blocker toxicity? Context: To compare the efficacy of a novel antidote, insulin, with standard treatments, glucagon and epinephrine, in a canine model of acute beta-blocker toxicity. Anesthetized dogs were fitted with instruments by means of thoracotomy and vascular cutdown for multiple cardiodynamic, hemodynamic, metabolic, and electrical measures. After basal measurements were taken, animals received intravenous propranolol (.25 mg/kg/minute) continuously for the remainder of the experiment. Toxicity was defined as a 25% decrease in the product of heart rate times mean blood pressure. Thirty minutes after the development of toxicity, toxic measures were taken (treatment 0 minutes), and then the animals (n = 6 each group) received either sham (saline solution), insulin (4 IU/minute with glucose clamped), glucagon (50 micrograms/kg bolus, then 150 micrograms/kg/hour infusion), or epinephrine (1 microgram/kg/minute). Animals were monitored until death or for 240 minutes. Propranolol decreased contractility, left ventricular pressure, and systemic blood pressure, and resulted in death of all sham-treated animals by 150 minutes. Six of six insulin-treated, four of six glucagon-treated, and one of six epinephrine-treated animals survived. Survival was greater for insulin-treated animals, compared with either glucagon-treated (P < .05) or epinephrine-treated animals (P < .02) by the log-rank test. Insulin-treated animals were characterized by improved cardiodynamics and hemodynamics, increased myocardial glucose uptake, and decreased serum potassium.
assistant
Insulin is a superior antidote compared with glucagon or epinephrine in an anesthetized canine model of acute beta-blocker toxicity. Final Decision: yes