右美托咪定对小儿全身麻醉围拔管期血流动力学及苏醒的影响

Effect of dexmedetomidine on haemodynamics and analepsia of general anesthesia for children during tracheal extubation period

目的比较手术结束前静脉泵注不同浓度的右关托咪定对小儿全身麻醉围拔管期的血流动力学及苏醒的影响。方法选择6—10岁，ASAⅠ～Ⅱ级，全身麻醉下行低温等离子腺样体消融术＋扁桃体摘除术的患儿84例，随机分为四组，右美托咪定0．7μg／kg组（A组），右美托咪定0．5μg/kg组（B组），右美托咪定0．3μg／kg组（C组），生理盐水组（D组）。术毕前30min静脉泵注相应药品，15min内泵注完毕。观察并记录用药前（T0），拔管前（T1），拔管时（T2），拔管后5min（T3）的收缩压（SBP）、舒张压（DBP）、心率（HR）、心肌耗氧量（MCO）及患儿的苏醒时间、拔管时间和不同时间点的警觉／镇静评分（OAA／S）。结果T2、T3时，与A、B组比较，C、D两组血压及HR、MCO均增高（P〈0．05）；A、B组间血压及HR、MCO比较差异无统计学意义（P〉0．05）。苏醒时间、拔管时间和不同时间点的OAA／S评分，B、C、D三组间比较差异无统计学意义（P〉0．05）；A组和B、C、D三组比较，拔管和苏醒时间延长，OAA／S评分减少（P〈0．05）。结论0．5μg／kg右美托咪定使患儿拔管期血流动力学平稳并能减少苏醒时间和拔管时间，增加对气管导管的耐受性，有利于患儿平稳度过麻醉苏醒期。

Objective To compare the effect of intravenous infusion of dexmedetomidine with different concentrations at the end of the surgery on haemodynamics and analepsia of general anesthesia for children during tracheal extubation period. Methods Eighty-four children with the age between 6 and 10 undergoing low-temperature plasma adenoid body ablation and tonsillectomy under general anesthesia at ASA Ⅰ-Ⅱ level were selected and randomly divided into 4 groups. 0. 7 μg/kg dexmedetomidine was used for group A, with 0. 5 μg/kg dexmedetomidine for group B, 0. 3 μg/kg dexmedetomidine for group C and normal saline for group D. Corresponding medicines were injected through vein 30 rain before the surgery and the injection was completed within 15 rain. The systolic pressure（ SBP）, diastolic pressure （DBP）, heart rate （HR） and myocardial oxygen consumption （MCO） before taking the medicine （ T0）, and the extubation （ T1 ）, during extubation （ T2 ） and 5 rain after the extubation （ T3 ） as well as analepsia time of children, extubation time and OAA/S grading at different time points were observed and recorded. Results At T2 and T3, compared with group A and group B, the blood pressure, HR, MCOof group C and group D were higher （P 〈 0.05）. There was no statistical significancedifference of the blood pressure, HR, MCO between group A and group B （ P 〉 0. 05 ）. As for analepsia time, extubation time and OAA/S grading at different time points, the differences among group B, group C and group D had no statistical significance （ P 〉 0. 05 ）. Comparing group A with group B, group C and group D, both extubation time and analepsia time extend and OAA/S grades decrease. P 〈0. 05）. Conclusions 0.5 μg/kg dexmedetomidine makes haemodynamics of children during the extubation peri- od stable, reduces analepsia time and extubation time and increases tolerance of endotracheal tubes, beneficial to sick children getting through anesthesia and aualepsia period stably.