RESUMO
OBJECTIVE: Understanding of how oscillometric waveforms (OMW) vary between pregnant and nonpregnant individuals remains low. An exploratory analysis was completed to assess for quantitative and qualitative changes in OMW and oscillometric envelope features in pregnancy. DESIGN AND METHODS: Eighteen pregnant individuals (over 20 weeks gestational age) and healthy, nonpregnant (HNP) women were recruited. Six HNP were matched to six healthy pregnant (HP) women, and six pregnant women with a hypertensive disorder of pregnancy (HDP) by age, arm circumference, and cuff size. Blood pressure measurements were completed per the International Organization for Standardization (ISO) protocol using a custom-built oscillometric device as the test device and two-observer mercury auscultation as the reference measurement. Auscultatory blood pressure and blood pressure derived from slope-based and fixed ratio algorithms were determined. OMW and envelope features were compared among groups. RESULTS: In HNP, HP, and HDP groups respectively: mean auscultatory blood pressure (systolic mean ± SD/diastolic mean ± SD) was 103.4â ±â 12.2/67.1â ±â 7.9; 109.5â ±â 3.1/58.1â ±â 6.4; 135.6â ±â 18.9/85.1â ±â 14.2â mmHg. HDP had significantly higher auscultatory systolic and diastolic blood pressure than the HP group ( P â =â 0.001). The pregnant groups had a lower average pulse width (mean ± SD: HNPâ =â 0.8â ±â 0 s, HPâ =â 0.6â ±â 0.1 s, HDPâ =â 0.6â ±â 0.1 s; HP vs. HNP mean difference [adjusted P value]: 0.2 [ P â =â 0.004], HDP vs. HNP 0.1 [ P â =â 0.018]) compared with the HNP group. The HDP group had a larger area under the OMW envelope than the HNP group (mean ± SD: HNP = 22.6â ±â 3.4; HDP = 28.5â ±â 4.2; HDP vs. HNP mean difference [adjusted P value]: 5.9 P â =â 0.05). CONCLUSION: In this exploratory work, differences in the OMW morphology and parameters were found in pregnancy and in hypertensive disorders of pregnancy compared with healthy controls. Even small differences may have important implications in algorithm development; further work comparing OMW envelopes in pregnancy is needed to optimize the algorithms used to determine blood pressure in pregnancy.
Assuntos
Hipertensão Induzida pela Gravidez , Oscilometria , Humanos , Feminino , Gravidez , Adulto , Hipertensão Induzida pela Gravidez/fisiopatologia , Oscilometria/instrumentação , Pressão Sanguínea , Determinação da Pressão Arterial/métodos , Determinação da Pressão Arterial/instrumentaçãoRESUMO
OBJECTIVE: Assess the accuracy of the BIOS BD240 home blood pressure (BP) monitor and wide-range cuff according to the International Organization for Standardization (ISO) 2018 standard. METHODS: Eighty-five subjects (aged ≥18 y) with arm circumferences between 24 and 43 cm were studied. Blinded, two-observer, mercury-based auscultation performed using a two-piece cuff chosen for upper arm size was used for reference measurements. Accuracy criteria 1 and 2 of the ISO standard were determined and Bland-Altman plots generated. RESULTS: Sixty percent of the study sample was female and 42% had hypertension. Mean device-to-reference standard differences in SBP/DBP were 0.0 ± 6.2/-0.2 ± 6.3 for criterion 1 and 0.0 ± 4.8/-0.2 ± 5.8 for criterion 2. CONCLUSION: The BIOS BD240 passed the requirements of the American National Standards Institute/Association for the Advancement of Medical Instrumentation/ISO standard for both SBP and DBP and can be recommended for use.