高压氧治疗缺氧缺血性脑病的应用特征

Characteristics of hyperbaric oxygen therapy for hypoxic-ischemic encephalopathy

目的:了解高压氧在治疗缺氧缺血性脑病方面的应用进展。资料来源:检索Medine1980-01/2005-01与高压氧治疗缺氧缺血性脑病临床及基础研究的文章,检索词“hyperbaricoxygen,hypoxic-ischemicencephalopathy”,并限定文章语言种类为英文。检索清华全文数据库2003-01/2005-12关于高压氧治疗缺氧缺血性脑病临床及基础研究的文章,限定文章语言种类为中文,检索词“高压氧,缺氧缺血性脑病”。资料选择:对资料进行初审,筛除明显不随机的研究,对剩余的文献开始查找全文。纳入标准为①随机对照研究;②实验或临床研究包含平行对照组。排除标准:重复性研究。资料提炼:共收集到109篇关于高压氧治疗缺氧缺血性脑病应用方面的文章,25个实验或临床研究符合纳入标准。排除的84篇为未随机研究或重复性研究。资料综合:高压氧可提高血氧浓度,改善各脏器组织氧的供应,改善脑组织代谢,促进脑损伤修复;高压氧可使脑组织内供氧正常的部位血管收缩,脑血流量减少,但可使受损部位的脑血管扩张,增加缺血区脑血流量,减轻脑水肿;提高脑干网状激活系统等部位的氧分压,从而在缺氧缺血性脑病时发挥对脑的保护和修复作用。高压氧可在脑缺血/再灌注损伤中能提高人和动物的存活率,使存活时间延长、脑梗死容量减少、行为功能改善。结论:高压氧治疗缺氧缺血性脑病,除少数学者对高压氧治疗缺氧缺血性脑病的效果持异议外,多数研究者利用动物模型从多个层面证明高压氧治疗缺氧缺血性脑病有一定效果,能改善缺氧缺血性脑病急性期的临床症状和体征,促进脑功能的康复和大脑发育,减少后遗症的发生,不过,用于实验研究的动物多数为成年动物,忽略了新生婴儿大脑处于高速发育期,可塑性极大这一至关重要因素,在评价疗效时只有近期疗效;选用的缺氧缺血性脑病动物模型与人类分娩所造成的新生儿缺氧缺血性脑病的临床现实情况存在较大差异。

OBJECTIVE： To investigate the applied development of hyperbaric oxygen therapy for hypoxic-isehemic encephalopathy. DATA SOURCES： A computer-based online search of Medline was undertaken for articles about clinical and basic researches on hyperbaric oxygen therapy for hypoxic-ischemic encephalopathy published in English between January 1980 and January 2005 with the key words of ＂hyperbaric oxygen, hypoxic-ischemic encephalopathy＇. Meanwhile, we searched Tsinghua Wanfang Full-text database for Chinese articles about clinical and basic researches on hyperbaric oxygen therapy for hypoxic-ischemic encephalopathy between January 2003 and December 2005 with the same key words in Chinese. STUDY SELECTION： The data were selected firstly to exclude the obvious non-randomized researches, and look up the full text of the rest literatureS. Inclusive criteria： ①randomized trial;②experimental or clinical researches containing parallel control group. Exclusive criteria： repetitive studies. DATA EXTRACTION： Among the 109 articles about application of hyperbaric oxygen for hypoxic-isehemic encephalopathy, 25 experimental or clinical researches were accorded with the inclusive criteria, the 84 excluded articles were non-randomized researches or repetitive studies. DATA SYNTHESIS： Hyperbaric oxygen can increase the concentration of blood oxygen, improve the supply of oxygen for each organ tissue and metabolism of brain tissue, promote the repair of brain injury; it makes the vessels of normal oxygen supply organs in brain tissue contract; brain blood flow reduce, hut make the cerebral vessels of injured parts expand, increase the blood flow in ischemic areas and release brain edema; it can also improve the oxygen partial pressure of brain stem reticular activating system, so as to protect and repair the brain in hypoxic-ischemic encephalopathy. Hyperbaric oxygen can improve the survival rate of human and animals with cerebral ischemic-reperfusion injury, prolong the survival time, decrease the cerebral infarction volume and improve the behavioral function. CONCLUSION： Except a few scholars objective to the effect of hyperbaric oxygen therapy on hypoxic-isehemic encephalopathy, many researchers have proved the effect of it by animal models from multiple aspects, they suggest that hyperbaric oxygen can improve the clinical symptoms and sings of hypoxic-ischemic encephalopathy at acute stage, promote the recovery of cerebral function and brain development and decrease the occurrence of sequela, however, most of the experimental animals are adult ones, which overlooks the brain of the newborn is at the rapid development stage with a great plasticity, so it can only evaluate the recent curative effect; there are significant differences between the experimental animal models and neonate with hypoxic-ischemic encephalopathy in clinic.