纳洛酮对细粒棘球蚴所致过敏性休克的影响

Experimental effects of naloxone on anaphylactic shock in sheep induced by Echinococcus granulosus

目的 :观察并评价纳洛酮对细粒棘球蚴所致过敏性休克的血流动力学影响及干预效果。 方法 :实验绵羊分为对照组、干预组 ,每组 6只 ,均为细粒棘球蚴感染的绵羊 ,采用新鲜包虫囊液攻击发敏 ,建立过敏性休克模型 ,干预组立即给予静脉注射纳洛酮 0 .1m g/ kg,然后每分钟 2μg/ kg持续输注。对照组用生理盐水输注。采用Swan- Ganz漂浮导管技术分别于休克前后测定血流动力学参数。 结果 :攻击发敏后 3 .5 m in,干预组和对照组MAP均迅速下降 ,而 MPAP、PCWP迅速升高 ,纳洛酮干预后 MAP迅速恢复 ,而对照组 MAP呈持续低水平状态 ,60 m in后才逐渐恢复。干预组 CO维持高水平状态 ,与对照组 CO差异有统计学意义 ,两组 MPAP、PCWP各时点之间的差异均无统计学意义。肺组织学检查 :两组均有肺间质及肺泡腔水肿、渗出、出血 ,对照组肺毛细血管周围组织中性粒细胞浸润、 型细胞缺失、肺泡萎陷等均较干预组明显。结论 :纳洛酮能促进过敏性休克 MAP、CO升高 ,改善体外周血流动力学状态 ,增加重要生命器官的血流灌注 ,并间接改善微循环 ,对 MPAP、PCWP没有明显降低作用 ,但可抑制肺泡透明膜的形成 ,防止肺泡萎陷 。

Objective: To study the experimental effects of naloxone on anaphylactic shock induced by Echinococcus granulosus(E.g). Methods: 12 sheep with anaphylactic shock induced by E.g were randomly divided into two groups. The naloxone group(N) was infused two doses at 0.1 mg/kg and 2 ug/kg·min -1 respectively via central vein, while the control group(C) was infused by normal saline(equal volume) only. Meantime, mean arterial pressure (MAP), heart rate(HR), mean pulmonary arterial pressure(MPAP), pulmonary capillary wedge pressure(PCWP), cardiac output(CO), cardiac index(CI) were measured during anaphylactic shock of administration of naloxone or normal saline. After challenging,all of the data were recorded at regular intervals. Results: The results showed that upon challenge, a11 sheep of the experimental group occurred severe anaphylactic shock. After 3.5 minutes,both of the naloxone group and the control group decreased sharply in MAP, while increased significantly in MPAP,PCWP. Meanwhile,naloxone significantly increased MAP(P<0.01) and CO(P<0.05). However, MPAP and PCWP in two groups were not significantly different(P>0.05) at different periods. Pulmonary histopathological studies showed that there was no difference of edema, exudation and hemorrhage in lung parenchyma and interstitium of naloxone and control groups. There were white cell infiltrafion, lung epithelial cell Ⅱ loss and lung alveolar collapse around capillaries in the control group more than those in the naloxone group. Based on experimental results, the heart and 1ung were the 'target organ' in the anaphylactic shock induced by E.g. Conclusion: naloxone can be benefit for MAP; elevation of CO during anaphylactic shock induced by E.g can improve the systematic peripherial hemodynamic changes, and can improve tissue oxygen supply temporarily. Naloxone showed no effect in decreasing MPAP and PCWP. But naloxone can prevent the formation of lung alveolar hyaline membrane, lung alveolar collapse and improve the depression of diffusion lung function.