摘要目的 评价吸入沙丁胺醇的剂量及吸入后不同时间测定FEV1不同的阳性判断标准对支气管舒张试验结果的影响.方法 选择支气管哮喘(简称哮喘)患者30例,COPD患者29例,健康对照组30名,吸入200 μg或400μg沙丁胺醇,吸入后分别于15、20、30 min重复测定FEV1,计算舒张试验阳性率;次日吸入另一剂量的沙丁胺醇再进行支气管舒张试验.统计学处理用SPSS 10.0软件.不同剂量支气管舒张剂及不同时间后舒张试验阳性率比较采用卡方检验.结果 以FEV1改善率≥12%,且FEV1增加绝对值＞200 ml为舒张试验阳性标准,哮喘组吸入200 μg沙丁胺醇后15、20、30 min时的舒张试验阳性者均为28例(28/30,93.3%),哮喘组3个时点间比较差异无统计学意义(x2=0.00,P＞0.05);吸入400 μg沙丁胺醇后15、20、30 min时的舒张试验阳性者分别为28例(28/30,93.3%)、29例(29/30,96.7%)、27例(27/30,90.0%),哮喘组3个时点间比较差异无统计学意义(x2=1.07,P＞0.05);比较吸入200 μg与400 μg沙丁胺醇后的舒张试验阳性者,在3个时点比较差异均无统计学意义(x2值均为0.00,P均＞0.05).COPD组和健康对照组舒张试验阳性率与吸入沙丁胺醇的剂量和观察时间亦无关系.吸入200 μg沙丁胺醇15 min后重复测定FEV1(以FEV1改善率≥12%,且FEV1增加绝对值＞200 ml为舒张试验阳性标准),诊断哮喘的灵敏度可达93.3%,特异性可达98.3%.结论 吸入200 μg沙丁胺醇15 min后重复测定FEV1,既可保证舒张试验的效能,又可减少药物用量及其不良反应,是一种理想的选择;以FEV1改善率≥12%,且FEV1增加绝对值＞200 ml为舒张试验阳性标准,诊断哮喘的效能优于其他舒张试验阳性标准.

abstractsObjective To evaluate the effects of different doses of salbutamol and observation times on bronchodilation test.Methods Three groups of subjects(30 patients with asthma,29 patients with COPD,and 30 normal controls)were included in this study.The forced expiratory volume in the first second (FEV1)was evaluated in the positive rates at 15,20,and 30 min after inhaling 200 μg or 400 μg salbutamol.On day 2,another dose of salbutamol was inhaled,and FEV1 measurement was performed repeatedly.SPSS 10.0 was used for statistical analysis.The positive rates after inhaling 200 μg and 400 μg salbuterol at the 15.20 and 30 min were compared with chi-square test.Resuits Using absolute change of FEV1＞200 ml and improving rate of FEV1≥12%as the positive standard,the positive rate of the asthmatic subiects at 15,20,and 30 min after inhaling 200 μg salbutamol was 28/30(93.3%),28/30(93.3%)and 28/30(93.3%,x2=0.00,P＞0.05).The positive rate of the asthmatic subjects at 15,20and 30 min after inhaling 400 μg salbutamol was 28/30(93.3%),29/30(96.7%),27/30(90.0%,x2=1.07.P＞0.05).The positive rate at 15.20 and 30 min were not significantly different between patients inhaling 200 μg and 400 μg salbutamol(x2=0.00,0.00,0.00,all P＞0.05).In the patients with COPD and in normal controls.the positive rate was not significantly different between patients inhaling 200 μg and 400 μg salbutamol.There was also no difference in the positive rate at different time.If using absolute change of FEV1＞200 ml and improving rate of FEV1≥12%as the positive standard,the best combination of sensitivity and specificity of diagnosing asthma was achieved.The sensitivity was 93.3%and the specificity was 98.3%.Conclusions FEV1 at 15 min after inhaling 200 μg salbutamol is the best choice as it is highly efficient and causes less side effects.We suggest that an absolute increase of FEV1＞200 ml and improving rate of FEV1≥12%to be the positive standard of diagnosing asthma.