The Effects of Propranolol and Esmolol on Blood Flow of Common Carotid Artery and Vital Signs in Rabbits / 대한마취과학회지

ABSTRACT

BACKGROUND: This study was planned to evaluate the influence of propranolol and esmolol on cerebral circulation and to estimate clinical implications and usefulness. METHODS: This study was designed to measure vital signs, cerebrospinal fluid pressure, cerebral perfusion pressure and blood flow velocity of common carotid artery. This was measured by Doppler Flowmeter after intravenous administration of propranolol 12.5, 25, 50 microgram/kg (P-12.5, P-25, P-50, respectively), and esmolol 0.5, 1.0, 2.0 mg/kg (E-0.5, E-1.0, E-2.0 group, respectively) at 1 or 2 minute intervals for 14 minutes. RESULTS: In the propranolol group (P-12.5, P-25 and P-50), the systolic blood pressure (SBP) significantly decreased since postinjection 1 minute and this decreased pressure continued throughout the entire experiment. But in esmolol group (E-0.5, E-1.0 and E-2.0), the SBP decreased significantly and rapidly recovered within 4 minutes. Heart rate significantly decreased in the propranolol group and continued throughout the experiment, but in the esmolol group the heart rate decreased and rapidly recovered within 10 minutes. The duration of the decreased heart rate in the esmolol group was shortened by decreasing the dosage. The blood flow velocity of the common carotid artery significantly decreased at 1 to 14 minutes after the injection of propranolol, but in group E-1.0, it was significantly decreased at 1 to 2 minutes, and in group E-2.0 at 1 to 3 minutes. CONCLUSIONS: The esmolol group showed less changes of SBP, heart rate and common carotid artery flow, and shorter duration of effect than the propranolol group. Mean blood pressure, cerebrospinal fluid pressure and cerebral perfusion pressure had no significant differences between propranolol and esmolol groups.