喉上神经阻滞下置入喉罩对血流动力学及儿茶酚胺的影响

目的观察喉上神经阻滞下置人喉罩对心血管系统的反应和血中儿茶酚胺的变化。方法选择无心血管疾病，ASA分级Ⅰ～Ⅱ级，择期行上下肢骨折手术的患者40例，随机分成两组：喉上神经阻滞组（B组）和对照组（c组），每组各20例。分别于下列时间点观察血流动力学变化：手术前（Tn），泵注普鲁泊福5min（T1），置入喉罩过程中（T2），置入喉罩后1min（B），置入喉罩后3min（T4），置人喉罩后5min（T5）。同时分别在T0、T5从动脉通路中抽取血液5ml。血标本用ELISA法测定儿茶酚胺的含量。结果两组患者麻醉诱导后平均动脉压（MAP）均下降（P〈0．05）；喉罩置入过程中，c组的MAP和心率明显升高，分别升高（22．00±8．50）mmHg（1mmHg=0．133kPa）和（19．75±2．22）次／min，差异有统计学意义（P〈0．01），而B组虽有升高，但差异无统计学意义（P〉0．05）。置入喉罩前后C组血中的肾上腺素和去甲肾上腺素含量比较差异有统计学意义（P〈0．01），而B组比较差异无统计学意义（P〉0．05）。结论喉上神经阻滞后，通过阻断局部的感觉传导，可减少置人喉罩对机体血流动力学的影响，抑制儿茶酚胺的释放。

Effect of bilateral superior laryngeal nerve block on preventing cardiovascular reaction and inhibiting secretion of catecbolamines secondary to inserting the laryngeal mask airway

Objective To investigate the effect of bilateral superior laryngeal nerve block on preventing cardiovascular responses and the level of catecholamines in the blood during the insertion of the laryngeal mask airway （LMA）. Methods Forty ASA Ⅰ or Ⅱ patients without cardiovascular disease undergoing limb fracture surgery were enrolled in the study. The patients were randomly divided into two groups, superior laryngeal nerve block group （group B ） and control group （group C ）,with 20 patients in each group. In the following phase to observe changes in blood flow dynamics： the basis of pre-operative value （T0）, 5 min after induction （T1）, process of LMA insertion （T2）, 1 min after LMA insertion （T3）, 3 min after LMA insertion （T4）, 5 min after LMA insertion （T5）. Meanwhile, blood samples were collected from artery channel at To and T5, and the level of catecholamines was checked by ELISA method. Results The mean arterial pressure（MAP） decreased after the induction of anesthesia in two groups（P 〈 0.05 ）. MAP and heart rate during inserting the LMA increased significantly in group C increased （22.00 ± 8.50） mm Hg （ 1 mm Hg =0.133 kPa） and （19.75 ±2.22） times/min, scparatcly] （P 〈0.01）, but there were no significant difference increase in group B （P 〉 0.05 ）. The levels of epinephrine and norepinephrine in group C increased significantly after LMA insertion （P〈0.01）, while there were no significant differences in group B （P〉 0.05）. Conclusion Blocking the superior laryngeal nerve could effectively reduce the cardiovascular responses and inhibite the release of catecholamines during the insertion of the LMA.