Effects of Fentanyl and Morphine on Epinephrine - induced Arrhythmia in Halothane Anesthetized Dogs / 대한마취과학회지

ABSTRACT

The purpose of this study was to elucidate the effects of fentanyl and morphine on the ability of epinephrine to induce arrhythmias in halothane-anesthetized dogs. Epinephrine was infused in progressively increasing doses from 0.5 ug/kg/min. Arrhythmogenic dose of epinephrine(ADE), defined as that induces 4 or more premature ventricular contractions within 15 s during 3 min iafusions of epinephrine, was determined before(control) and after pretreatment of either fentanyl(6 ug/kg i.v. plus 6 pg/kg/hr) or morphine(0.2mg/kg i.v. plus 0.2 mg/kg/hr). Blood pressure and heart rate were also measured immediately before(baseline), immediately after infusion of epinephrine. The results were as follows. l) Fentanyl and morphine increased ADE by 37%(2.19+/-0.49 to 3.00+/-0.44 ug/kg/min, p<0.01) and by 43%(2.50+/-0.60 to 3.58+/-0.93 ug/kg/min, p<0.05), respectively. 2) Percent increases in systolic blood pressure at control were similar to those after pretreatment with fentanyl or morphine in both groups, but systolic blood pressures at the time of arrhythmia after pretreatment were lower than those at control in fentanyl(p<0.05) and morphine group(NS). 3) Fentanyl and morphine decreased heart rate by 27%(127+/-8 to 93+/-6 beats/min, p<0.001) and by 13%(118+/-5 to 103+/-5 beats/min, p<0.05), respectively. These results suggest that fentanyl or morphine inhibits epinephrine induced arrhythmias during halothane-oxygen anesthesia. Thus, pretreatment of surgical patients, who were supposed to receive epinephrine during halothane anesthesia, with either fentanyl or morphine might be safe.