Co-Investigator(Kenkyū-buntansha) |
COULTHARD Paul The University of Manchester, Turner Dental School Oral surgery, Senior lecturer, 歯学部, 講師
MIURA Makoto The Nippon Dental University, Dental anesthesiology, Research fellow, 歯学部, 助手 (60147816)
FURUYA Hideki The Nippon Dental University, Dental anesthesiology, Professor, 歯学部, 教授 (30060429)
PAUL Coultha マンチェスター大学, 歯学部, 講師
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Budget Amount *help |
¥4,300,000 (Direct Cost: ¥4,300,000)
Fiscal Year 1998: ¥1,400,000 (Direct Cost: ¥1,400,000)
Fiscal Year 1997: ¥1,200,000 (Direct Cost: ¥1,200,000)
Fiscal Year 1996: ¥1,700,000 (Direct Cost: ¥1,700,000)
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Research Abstract |
Clonidine is a prototype of alpha^2-agonist and was originally introduced to clinical practice as an antihypertensive drug. The objective of this study is to evaluate the effects of clonidine as anadjunct in intravenous conscious sedation. We assessed the effects on haemodynamic and adrenergic responses to nociceptive stimuli, sedation and analgesic effects. 20 volunteers received 2 mu g/kg of clonidine intravenously. Constant current, square-wave electric stimuli (duration 20 msec, interval 100 msec, train 10, 5 mA) were delivered as nociceptive stimuli to the median nerve. We measured blood pressure, heart rate(HR) every 5 min, and plasma levels of adrenaline, noradrenaline and cortisol before and 15, 30, 45, 60 and 90 min after clonidine injection, sedative and analgesic effects were measured by visual analogue scale before and 15, 30, 45, 60 and 90 min after drug. HR decreased significantly 0, 20, 30, 50 and 60 minutes after clonidine injection. The maximum decrease in HR was within 10% (8.4%). Systoli pressure(SP) decreased singnificantly 20 minutes later. There was no significant difference from the control at any point in diastolic pressure(DP). The decrease in SP was within 10%, and 2mug/kg of intravenous clonidine did not induce severe hypotension throughout the study in any subject. Clonidine produced significant decrease in adrenaline levels 15 and 60 minutes after intravenous injection. Noradrenaline concentrations significantly decreased 15, 60 and 90 minutes after the injection. Plasma cortisol levels showed significant differences from the control 15, 30, 60 and 90 minutes after clonidine administration. Dry mouth and fatigue or weariness were the most frequent perceptive side effects. 2 mu g/kg of intravenous clonidine did not induce severe bradycardia, hypotension or other serious side effects. it attenuated the adrenergic responses to nociceptive stimuli, and exerted good sedative effect.
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