title: Atropine dose in acute myocardial infarction in man.
abstract: Heart rate response to intravenous atropine therapy in acute myocardial infarction (MI) was assessed from detailed studies performed on 18 of 492 consecutively admitted coronary care unit patients. Atropine was given for extreme bradycardia (less than 40/min) or bradycardia (less than 60/min) coincident with hypotension or ventricular premature beats. 14 patients had posterior and 4 anterior infarction. Degree of cardioacceleration evoked by atropine depended upon drug dose and route of administration. Atropine, 0.0053-0.0088 mg/kg, given within 15 sec increased heart rate by 20-72/min but never beyond a peak rate of 120. Larger atropine doses, 0.120-0.148 mg/kg, increased heart rate by 51-92/min and, in four to five instances to a peak rate exceeding 120/min. Intramuscular atropine was associated with paradoxical slowing of heart rate in one case. Multiple neural, hormonal, and circulatory factors can modify heart rate response to fixed amounts of intravenous atropine but 0.008 mg/kg represents a safe and suitable initial drug dose for use in acute MI.
mesh_terms: D000208:Acute Disease; D001285:Atropine / Q000008:administration & dosage* / Q000627:therapeutic use; D001919:Bradycardia / Q000188:drug therapy; D004305:Dose-Response Relationship, Drug; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D007275:Injections, Intravenous; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction / Q000187:drug effects; D009203:Myocardial Infarction / Q000188:drug therapy*; D013268:Stimulation, Chemical; D013997:Time Factors
chemical_list: D001285:Atropine