Zwanenburg Alex, Hermans Ben Jm, Andriessen Peter, Niemarkt Hendrik J, Jellema Reint K, Ophelders Daan Rmg, Vullings Rik, Wolfs Tim Gam, Kramer Boris W, Delhaas Tammo
Department of Biomedical Engineering, Maastricht University, Maastricht, The Netherlands.
MHeNs School for Mental Health and Neuroscience, Maastricht University, Maastricht, The Netherlands.
Pediatr Res. 2016 Jun;79(6):907-15. doi: 10.1038/pr.2016.21. Epub 2016 Feb 11.
Current methods for assessing perinatal hypoxic conditions did not improve infant outcomes. Various waveform-based and interval-based ECG markers have been suggested, but not directly compared. We compare performance of ECG markers in a standardized ovine model for fetal hypoxia.
Sixty-nine fetal sheep of 0.7 gestation had ECG recorded 4 h before, during, and 4 h after a 25-min period of umbilical cord occlusion (UCO), leading to severe hypoxia. Various ECG markers were calculated, among which were heart rate (HR), HR-corrected ventricular depolarization/repolarization interval (QTc), and ST-segment analysis (STAN) episodic and baseline rise markers, analogue to clinical STAN device alarms. Performance of interval- and waveform-based ECG markers was assessed by correlating predicted and actual hypoxic/normoxic state.
Of the markers studied, HR and QTc demonstrated high sensitivity (≥86%), specificity (≥96%), and positive predictive value (PPV) (≥86%) and detected hypoxia in ≥90% of fetuses at 4 min after UCO. In contrast, STAN episodic and baseline rise markers displayed low sensitivity (≤20%) and could not detect severe fetal hypoxia in 65 and 28% of the animals, respectively.
Interval-based HR and QTc markers could assess the presence of severe hypoxia. Waveform-based STAN episodic and baseline rise markers were ineffective as markers for hypoxia.
目前评估围产期缺氧状况的方法并未改善婴儿预后。已提出多种基于波形和基于间期的心电图标志物，但未进行直接比较。我们在标准化的绵羊胎儿缺氧模型中比较心电图标志物的性能。
69只妊娠0.7期的胎羊在脐带闭塞（UCO）25分钟期间（导致严重缺氧）之前4小时、期间及之后4小时记录心电图。计算了多种心电图标志物，包括心率（HR）、心率校正的心室去极化/复极化间期（QTc）以及ST段分析（STAN）发作期和基线上升标志物，类似于临床STAN设备警报。通过将预测的和实际的缺氧/正常氧合状态进行关联，评估基于间期和基于波形的心电图标志物的性能。
在所研究的标志物中，HR和QTc表现出高敏感性（≥86%）、特异性（≥96%）和阳性预测值（PPV）（≥86%），并且在UCO后4分钟时能在≥90%的胎儿中检测到缺氧。相比之下，STAN发作期和基线上升标志物表现出低敏感性（≤20%），分别在65%和28%的动物中无法检测到严重胎儿缺氧。
基于间期的HR和QTc标志物可评估严重缺氧的存在。基于波形的STAN发作期和基线上升标志物作为缺氧标志物无效。
