Howlett Thomas, Lerman Jerrold
The Hospital for Sick Children, University of Toronto, Toronto, ON, Canada.
Paediatr Anaesth. 2006 May;16(5):523-9. doi: 10.1111/j.1460-9592.2006.01858.x.
Local anesthetics inhibit mediator and free radical release from polymorphonuclear granulocytes and migration to their site of action. In a recent study, lidocaine significantly improved the alveolar-arterial oxygen difference gradients (A-aDO2) after tracheal instillation of acid in rabbits. The purpose of the current study was to evaluate the effects of lidocaine and pulse-dose steroids on human breast milk (HBM)-induced lung injury in rabbits.
After Animal Care Committee approval, six adult rabbits were assigned to each of three treatments: control, lidocaine, and steroids. After induction of anesthesia and controlled ventilation, acidified HBM at pH 1.8 and volume 1.2 ml.kg(-1) was instilled into the trachea. Rabbits in the lidocaine group received lidocaine 2 mg.kg(-1) i.v. before tracheal instillation and then 2 mg.kg(-1).h(-1) i.v. continuously. Rabbits in the steroid group received 30 mg.kg(-1) methylprednisolone before tracheal instillation. A-aDO2, static compliance and blood for white cell count, and cytokine interleukin-8 (IL-8) concentration were obtained at baseline and at 1 and 4 h postinstillation. After 4 h, the rabbits were killed. The left upper lobe was isolated and excised to determine the wet/dry ratio. The right lung was lavaged with 30 ml normal saline to determine the white cell count and the concentrations of albumin and IL-8. Data were analyzed using one- or two-way anova with repeated measures and an Student-Newman-Keuls (SNK) posthoc test (P < 0.05).
All rabbits completed the protocol. A-aDO2 and CO2 tensions increased significantly at 1 and 4 h compared with baseline, although there were no differences among the treatments (P < 0.05). Compliance in the control group decreased compared with lidocaine and steroids.
We conclude that preemptive lidocaine and steroids attenuate in part HBM-induced lung injury in rabbits.
局部麻醉药可抑制多形核粒细胞释放介质和自由基，并阻止其向作用部位迁移。在最近一项研究中，利多卡因显著改善了兔气管内滴注酸后肺泡-动脉氧分压差梯度（A-aDO2）。本研究的目的是评估利多卡因和脉冲剂量类固醇对兔人乳（HBM）诱导的肺损伤的影响。
经动物护理委员会批准，将6只成年兔分为三组进行不同处理：对照组、利多卡因组和类固醇组。诱导麻醉并控制通气后，将pH值为1.8、体积为1.2 ml·kg⁻¹的酸化HBM滴入气管。利多卡因组的兔在气管内滴注前静脉注射2 mg·kg⁻¹利多卡因，然后以2 mg·kg⁻¹·h⁻¹的速度持续静脉注射。类固醇组的兔在气管内滴注前接受30 mg·kg⁻¹甲泼尼龙。在基线以及滴注后1小时和4小时获取A-aDO2、静态顺应性以及白细胞计数和细胞因子白细胞介素-8（IL-8）浓度的血样。4小时后，处死兔。分离并切除左上叶以测定湿/干比。用30 ml生理盐水灌洗右肺以测定白细胞计数以及白蛋白和IL-8的浓度。使用单因素或双因素方差分析及重复测量，并采用Student-Newman-Keuls（SNK）事后检验进行数据分析（P < 0.05）。
所有兔均完成实验方案。与基线相比，1小时和4小时时A-aDO2和二氧化碳分压显著升高，尽管各处理组之间无差异（P < 0.05）。与利多卡因组和类固醇组相比，对照组的顺应性降低。
我们得出结论，预防性使用利多卡因和类固醇可部分减轻兔HBM诱导的肺损伤。
