Abstract:

Objective　To explore the relationship between increased plasma D-dimer level and secondary persistent pulmonary hypertension of the newborn (PPHN). Methods　A total of 100 newborns diagnosed with pulmonary hypertension (PH) who were hospitalized in the neonatal intensive care unit of Huadu District People's Hospital of Guangzhou from June 1, 2020 to May 31, 2023 were selected as the study objects. They were divided into a PPHN group (33 cases) and a PH group (67 cases) based on presence of patent ductus arteriosus (PDA) or atrial septal defect (ASD) or patent foramen ovale (PFO) with right-to-left or bidirectional shunt, or based on whether the ventricular septum was protruded to the left. The plasma D-dimer concentration of all subjects were determined by enzyme-linked immunofluorescence assay. The difference of plasma D-dimer level between the two groups was compared, the relationship between D-dimer level and pulmonary artery systolic blood pressure (PASP) was analyzed, the value of D-dimer level in predicting PPHN was analyzed by receiver operating characteristic curve (ROC), and the related risk factors of PPHN were analyzed by multivariate logistic regression analysis. Independent sample t test, Mann-Whitney U test, χ² test, rank sum test, and Pearson correlation analysis were used. Results　The level of plasma D-dimer in the PPHN group was higher than that in the PH group [5 421.25 (3 311.23, 8 079.45) µg/L vs. 2 799.14 (2 253.28, 3 589.12) µg/L], with a statistically significant difference (Z=4.667, P<0.001). The D-dimer level was positively correlated with PASP (r=0.671, P<0.001). The area under the curve for predicting PPHN with D-dimer level was 0.788 (P<0.001). When the maximum Youden index was 0.518, the cut-off value of D-dimer level was 3 770.265 µg/L, and the sensitivity and specificity for predicting PPHN occurrence were 0.727 and 0.791. Multivariate logistic regression analysis showed that plasma D-dimer level >3 770 µg/L, acidosis (pH <7.2), HCO₃^- ≤18 mmol/L, and blood lactic acid >3 mmol/L were independent risk factors for PPHN (all P<0.05). Conclusion　The abnormal increase of D-dimer level may be an important factor that causes or promotes secondary PPHN.

Key words:

Persistent pulmonary hypertension of the newborn, Secondary, Pulmonary artery systolic blood pressure, D-dimer

摘要：

目的　探讨血浆D-二聚体水平升高与继发性新生儿持续性肺动脉高压（PPHN）的关系。方法　选取2020年6月1日至2023年5月31日在广州市花都区人民医院新生儿重症监护室住院的100例诊断为肺动脉高压（PH）的新生儿为研究对象，根据其心房和/或动脉导管水平血液是否存在右向左分流或双向分流，或室间隔是否向左侧凸起，分为PPHN组（33例）和PH组（67例），采用酶联免疫荧光法检测所有受试儿血浆D-二聚体浓度，比较两组新生儿的血浆D-二聚体水平的差异，分析D-二聚体水平与其肺动脉收缩压（PASP）的关系，利用受试者操作特征曲线（ROC）分析D-二聚体水平预测PPHN的价值，并对PPHN的相关危险因素进行多因素logistic回归分析。采用独立样本t检验、Mann-Whitney U检验、χ²检验、秩和检验、Pearson相关性分析。结果　PPHN组患儿血浆D-二聚体水平高于PH组 ［5 421.25（3 311.23，8 079.45）µg/L比2 799.14（2 253.28，3 589.12）µg/L］，差异有统计学意义（Z=4.667，P<0.001），且D-二聚体水平与PASP呈正相关（r=0.671，P<0.001）。用D-二聚体水平预测PPHN的曲线下面积为0.788（P<0.001），当约登指数最大为0.518时，D-二聚体水平截断值为3 770.265 µg/L，其预测PPHN发生的灵敏度为0.727，特异度为0.791。多因素logistic回归分析显示，血浆D-二聚体水平>3 770 µg/L、酸中毒（pH<7.2）、HCO₃^-≤18 mmol/L及血乳酸>3 mmol/L均是PPHN发生的独立危险因素（均P<0.05）。结论　D-二聚体水平异常升高可能是引起或促进继发性PPHN发生的重要因素。

关键词:

新生儿持续性肺动脉高压, 继发性, 肺动脉收缩压, D-二聚体