可乐定降低异氟醚最低肺泡有效浓度的研究

Reduction of MAC of isoflurane by administration of clonidine

研究了麻醉前应用可乐定影响异氟醚最低肺泡有效浓度(MAC)的效应。设可乐定组和对照组各15例,采用随机双盲法给药,根据Eger法确定MAC值。发现麻醉前2小时口服可乐定5μg/kg,可使异氟醚1MAC从对照组的1.185%降至0.775%,降低百分率为34.60%。推测此与可乐定的中枢性镇静、镇痛等效应有关。证实可乐定可做为麻醉前用药,降低异氟醚MAC。研究中采用皮肤电刺激为切皮刺激确定MAC预设范围,有实用价值。

To evaluate the effects of clonidine on the MAC value of isoflurane, thirty adult patients, ASA grade Ⅰ to Ⅱ. scheduled for elective operation, were randomly allocated to be premedicated with placebo (group Ⅰ) or clonidine 5μg/kg P. O. (group Ⅱ). 2 hours before isoflurane anesthesia in double blind method. The electric stimulation (45v. 200Hz. lasting one minute) to the forearm skine was used to estimate the MAC of isoflurane before skin incision (SI), and the responses to SI were applied to defining the MAC during SI. The results revealed that as compared witb those of placebo in group Ⅰ. the MAC of isoflurane kept statistically unchanged before SI (P>0.05). and reduced by 34.6% during SI(P<0.05). It is suggested that clonidine may properly serve as a premedicant to reduce the reqire ment of isoflurane.