Padwal Raj, Jalali Afrooz, McLean Donna, Anwar Saifal, Smith Kevan, Raggi Paolo, Ringrose Jennifer S
Department of Medicine.
Mazankowski Heart Institute.
Blood Press Monit. 2019 Feb;24(1):33-37. doi: 10.1097/MBP.0000000000000356.
Fixed-ratio and slope-based algorithms are used to derive oscillometric blood pressure (BP). However, a paucity of published data exists assessing the accuracy of these methods. Our objective was to determine the accuracy of fixed-ratio and slope-based algorithms in healthy adults and in adults with cardiovascular risk factors.
Overall, 85 healthy adults (age≥18 years) and 85 adults with cardiovascular risk factors were studied. Three oscillometric and four two-observer mercury-based auscultation measurements were performed in each, according to International Standards Organization 2013 methodology. Two fixed-ratio algorithms and one slope-based algorithm were applied to process oscillometric waveform envelopes and derive oscillometric BP. Paired and unpaired t-tests were used to compare mean oscillometric BP within and between each group, respectively.
For healthy adults, mean age was 50.3±17.8 years, mean arm circumference was 30.4±3.8 cm, and 62% were female. In the cardiovascular risk group, mean age was 63.8±12.4 years, mean arm circumference was 31.9±4.2 cm, and 62% were female. For systolic BP, the fixed-ratio algorithms produced the lowest mean error and narrowest SD. For diastolic BP, mean errors were similar for all three algorithms, but the fixed-ratio algorithms had higher precision. The comparison of healthy adults and those with cardiovascular risk factor showed high variability for systolic and diastolic BP (SD: 8.113.9 mmHg).
In both healthy adults and in those with cardiovascular risk factors, the fixed-ratio technique performed better than the slope-based algorithm. High between-group variability indicates that subject-specific algorithms may be needed.
固定比率和基于斜率的算法用于推导示波法血压（BP）。然而，评估这些方法准确性的已发表数据很少。我们的目的是确定固定比率和基于斜率的算法在健康成年人和有心血管危险因素的成年人中的准确性。
总共研究了85名健康成年人（年龄≥18岁）和85名有心血管危险因素的成年人。根据国际标准化组织2013年的方法，对每个人进行了三次示波法测量和四次双观察者汞柱听诊测量。应用两种固定比率算法和一种基于斜率的算法来处理示波波形包络并推导示波法血压。分别使用配对和非配对t检验来比较每组内和组间的平均示波法血压。
健康成年人的平均年龄为50.3±17.8岁，平均臂围为30.4±3.8厘米，62%为女性。在心血管风险组中，平均年龄为63.8±12.4岁，平均臂围为31.9±4.2厘米，62%为女性。对于收缩压，固定比率算法产生的平均误差最低，标准差最窄。对于舒张压，所有三种算法的平均误差相似，但固定比率算法具有更高的精度。健康成年人与有心血管危险因素的成年人之间的比较显示，收缩压和舒张压的变异性很高（标准差：8.1 - 13.9 mmHg）。
在健康成年人和有心血管危险因素的成年人中，固定比率技术的表现优于基于斜率的算法。组间的高变异性表明可能需要针对个体的算法。
