晕厥儿童病因学及其临床特征的研究

目的分析晕厥儿童的病因分布并对各种病因晕厥儿童的临床特征加以分析,以提高其诊断效率。方法回顾性分析在北京大学第一医院儿科就诊的以“晕厥”为主诉的154例患儿的临床资料。结果自主神经介导的反射性晕厥是晕厥患儿的最常见的病因,占所有患儿的65．6％。其次为心源性晕厥,占所有患儿的6．5％。此外,还包括精神性疾病、神经源性及代谢性疾病导致的晕厥。自主神经介导的反射性晕厥、精神性晕厥患儿多见于青春期女孩,发病年龄大于心源性、神经源性及代谢性疾病导致的晕厥患儿（均P〈0．05）;心源性及精神性晕厥患儿的晕厥发作次数则显著多于自主神经介导的反射性晕厥、神经源性及代谢性疾病导致的晕厥患儿（均P〈0.05）。通过logistic回归分析显示,患儿的晕厥次数及晕厥发生时的体位对判断晕厥病因具有重要的意义（P〈0．05）。心电图的检查对发现心源性晕厥儿童具有重要意义。其他检查包括脑电图、Holter心电图、超声心动图检查及精神学评估在寻找晕厥儿童病因方面的意义有限。直立倾斜试验对诊断及鉴别诊断自主神经介导的反射性晕厥具有重要的意义。结论导致儿童晕厥的病因众多,可选择的辅助检查也有多种,但详细的病史收集、体格检查及心电图检查是诊断晕厥儿童的基础。

Etiologic and clinical characteristics of syncope in children

OBJECTIVE: Syncope is a common problem in children and adolescents. Such an event may have multiple possible causes, ranging from benign conditions to life-threatening diseases. Syncope is a major challenge for the practicing physicians. It is very important to know the etiologic and clinical characteristics of syncope in children. This study aimed to improve diagnostic efficacy of syncope in children by analyzing the etiology and clinical characteristics of syncope. METHODS: The investigators retrospectively analyzed the causes of syncope and diagnostic workup of 154 consecutive children seen in Department of Pediatrics, Peking University First Hospital because of a syncopal event. RESULTS: Autonomic-mediated reflex syncope (AMS) was the most common cause of syncope (65.6%), whereas cardiac disorders were found in 10 cases (6.5%) comprising the second cause of syncope in children. Other causes included psychologic problems and neurological and metabolic disorders. Although many causes were studied, 25 cases (16.2%) were found to have uncertain etiologies yet. The children with AMS were commonly seen in pubertal girls, and they had clear inducement of syncope and prodromes. The children with cardiac syncope often had history of cardiac diseases, and they were often younger than those with AMS. Lack of prodromes of syncope, exercise-related syncope, syncope spells seen in any body position, frequent syncope spells and sudden death in family were clues of cardiac syncope. Neurological disorders should be considered if there are any of the followings: syncope with seizure activity, syncope spells seen in any position, and a postictal phase of disorientation or neurologic abnormal signs. A metabolic cause was entertained when the child had a history of metabolic diseases, prolonged anger, or violent vomiting and diarrhea. Children with psychiatric disorders were adolescent girls with prolonged syncope spells, and had more frequent syncopal episodes. Most children with syncope were evaluated by many of diagnostic tests, but most of those tests were not goal-directed approach. Since persons with cardiac syncope were at increased risk for death from any cause, electrocardiography was recommended in almost all children with syncope. Neurologic testing including electroencephalography, computed tomography, etc. were rarely helpful unless neurologic signs and symptoms are present. Holter electrocardiography and echocardiography were most useful in children with suspected cardiac syncope. There was little benefit of screening cardiac enzyme in children with syncope. Routine blood tests (blood electrolytes and blood glucose, etc) rarely yield diagnostically useful information unless the children had the history of metabolic diseases. Head-up tilt testing was most useful in children with recurrent syncope in whom heart disease was not suspected. The children with frequent syncope, long lasting syncopal episode and clear psychiatric inducement of syncope should be evaluated by psychiatric testing. CONCLUSION: Syncope in children may result from a wide variety of causes, and clinicians often use a wide range of investigation to try to achieve a diagnosis. But most of investigations have low diagnostic yield. Thorough history taking, physical examination and electrocardiography are the core of the syncope workup.