血液透析前后血浆B型钠尿肽变化及对心力衰竭的诊断价值

The change of B-type natriuretic peptide(BNP) levels before and after dialysis and its diagnostic value for heart failure

目的观察慢性肾功能不全病人血液透析前后血浆B型钠尿肽水平(BNP)的变化及对合并心力衰竭患者的诊断价值。方法观察56例慢性肾功能不全病人血液透析前,透析后即刻,3、6、24h的血浆BNP水平。并测定32例健康人作为对照。结果56例慢性肾功能不全病人血液透析前血浆BNP水平为(284±369)pg/ml,透析后即刻(371±425)pg/ml,3h(265±308)pg/ml,6h(204±242)pg/ml,24h(230±288)pg/ml(P<0.001)。健康者BNP为(37±37)pg/ml,有心功能不全症状及心超异常者血透前BNP为(595±438)pg/ml,无心功能不全症状及心超正常者BNP为(98±110)pg/ml(P<0.001)。BNP诊断心功能不全的ROC曲线下面积在血透后6h最大,为0.929。以BNP99pg/ml为界值诊断慢性肾功能不全病人、血液透析病人心功能不全敏感性为0.905,特异性为0.686,以225pg/ml为界值敏感性0.667,特异性为0.971。结论慢性肾功能不全血液透析病人血浆BNP水平明显高于正常,在血液透析后有一先增高后下降再增高的过程。慢性肾功能不全病人血浆BNP有助于心功能不全检出,在血透后6h采血测定诊断价值最大。BNP低于99pg/ml有助于排除心功能不全,高于225pg/ml有助于确立心功能不全诊断。

Objective To investigate the change of B - type natriuretic peptide（BNP） levels before and after dialysis its diagnostic value for heart failure . Methods The BNP levels were determined in 56 patients of chroic renal failure before and after dialysis and in 30 healthy people as control. Results The BNP levels in 56 patients betore dialysis, and right, 3 hours, 6 hours, 24 hours ＂after dialysis were （284 ± 369） pg/ml, （371 ± 425） pg/ml, （265 ± 308） pg/ml, （204 ± 242） pg/ml, （230 ± 288 ） pg/ml respectively（ P 〈 0. 001 ）. The BNP levels were （595 ± 438） pg/ml in patients with heart dysfunction, （98 ± 110） pg/ml in patients without beart dysfunction and （37 ± 37） pg/ml in healthy people（ P 〈 0. 001 ）. The biggest ROC area of BNP diagnosing heart failure in patients with dialysis was 0. 929 at 6 hottrs after dialysis. BNP had a sensibility of 0. 905 and specificity of 0. 686 to diagnose heart failure in patients with dialysis at a cutoff value of 99pg/ml, and a sensibility of 0. 667 and specificity of 0. 971 at a cutoff value of 225pg/ml. Conclusions The BNP levels are higher in patients with dialysis than those in healthy people, regardless of patients＇ heart function and have a process of temperary increasing , then decreasing and increasing again. Measurement of BNP in patients with dialysis contributes to the diagnosis of heart dysfunction and that at the time point 6h after dialysis has the best diagnositc value. BNP lower than 99 pg/ml can help to exclude heart failure and contributes to heart failure diagnosis when higher than 225 pg/ml.