The assessment of blood pressure in pregnant women: pitfalls and novel approaches.

Accurate assessment of blood pressure is fundamental to the provision of safe obstetrical care. It is simple, cost effective, and life-saving. Treatments for preeclampsia, including antihypertensive drugs, magnesium sulfate, and delivery, are available in many settings. However, the instigation of appropriate treatment relies on prompt and accurate recognition of hypertension. There are a number of different techniques for blood pressure assessment, including the auscultatory method, automated oscillometric devices, home blood pressure monitoring, ambulatory monitoring, and invasive monitoring. The auscultatory method with a mercury sphygmomanometer and the use of Korotkoff sounds was previously recommended as the gold standard technique. Mercury sphygmomanometers have been withdrawn owing to safety concerns and replaced with aneroid devices, but these are particularly prone to calibration errors and regular calibration is imperative to ensure accuracy. Automated oscillometric devices are straightforward to use, but the physiological changes in healthy pregnancy and pathologic changes in preeclampsia may affect the accuracy of a device and monitors must be validated. Validation protocols classify pregnant women as a "special population," and protocols must include 15 women in each category of normotensive pregnancy, hypertensive pregnancy, and preeclampsia. In addition to a scarcity of devices validated for pregnancy and preeclampsia, other pitfalls that cause inaccuracy include the lack of training and poor technique. Blood pressure assessment can be affected by maternal position, inappropriate cuff size, conversation, caffeine, smoking, and irregular heart rate. For home blood pressure monitoring, appropriate instruction should be given on how to use the device. The classification of hypertension and hypertensive disorders of pregnancy has recently been revised. These are classified as preeclampsia, transient gestational hypertension, gestational hypertension, white-coat hypertension, masked hypertension, chronic hypertension, and chronic hypertension with superimposed preeclampsia. Blood pressure varies across gestation and by ethnicity, but gestation-specific thresholds have not been adopted. Hypertension is defined as a sustained systolic blood pressure of ≥140 mm Hg or a sustained diastolic blood pressure of ≥90 mm Hg. In some guidelines, the threshold of diagnosis depends on the setting in which blood pressure measurement is taken, with a threshold of 140/90 mm Hg in a healthcare setting, 135/85 mm Hg at home, or a 24-hour average blood pressure on ambulatory monitoring of >126/76 mm Hg. Some differences exist among organizations with respect to the criteria for the diagnosis of preeclampsia and the correct threshold for intervention and target blood pressure once treatment has been instigated. Home blood pressure monitoring is currently a focus for research. Novel technologies, including early warning devices (such as the CRADLE Vital Signs Alert device) and telemedicine, may provide strategies that prompt earlier recognition of abnormal blood pressure and therefore improve management. The purpose of this review is to provide an update on methods to assess blood pressure in pregnancy and appropriate technique to optimize accuracy. The importance of accurate blood pressure assessment is emphasized with a discussion of preeclampsia prediction and treatment of severe hypertension. Classification of hypertensive disorders and thresholds for treatment will be discussed, including novel developments in the field.

Developing and evaluating non-invasive healthcare technologies for a group of female participants from a socioeconomically disadvantaged area.

When compared to the general population, socioeconomically disadvantaged communities frequently experience compromised health. Monitoring the divide is challenging since standardized biomedical tests are linguistically and culturally inappropriate. The aim of this study was to develop and test a unique mobile biomedical testbed based on non-invasive analysis, as well as to explore the relationships between the objective health measures and subjective health outcomes, as evaluated with the World Health Organization Quality of Life survey. The testbed was evaluated in a socioeconomically disadvantaged neighborhood in Malmö, which has been listed as one of the twelve most vulnerable districts in Sweden. The study revealed that compared to conventional protocols the less intrusive biomedical approach was highly appreciated by the participants. Surprisingly, the collected biomedical data illustrated that the apparent health of the participants from the ethnically diverse low-income neighborhood was comparable to the general Swedish population. Statistically significant correlations between perceived health and biomedical data were disclosed, even though the dependences found were complex, and recognition of the manifest complexity needs to be included in further research. Our results validate the potential of non-invasive technologies in combination with advanced statistical analysis, especially when combined with linguistically and culturally appropriate healthcare methodologies, allowing participants to appreciate the significance of the different parameters to evaluate and monitor aspects of health.

Assessment of Hypertension Control Among Adults Participating in a Mobile Technology Blood Pressure Self-management Program.

Importance: It is unclear whether mobile technology hypertension self-management programs are associated with blood pressure (BP) control. Objective: To examine whether engagement with a hypertension self-management program with a BP monitor and connected smartphone application with clinically based digital coaching was associated with BP control during a follow-up period of as long as 3 years. Design, Setting, and Participants: This cohort study enrolled US adults with elevated BP or hypertension between January 1, 2015, and July 1, 2020. The hypertension self-management program was provided through the participant's (or their spouse's) employer health plan. Exposures: Program engagement, defined by average number of application sessions. Main Outcomes and Measures: Systolic and diastolic BP measured by a US Food and Drug Administration-cleared BP monitor, with categories defined as normal (systolic BP, <120 mm Hg), elevated (systolic BP, 120-129 mm Hg), stage 1 hypertension (systolic BP, 130-139 mm Hg), and stage 2 hypertension (systolic BP ≥140 mm Hg). Other measures included age, gender, depression, anxiety, diabetes, high cholesterol, smoking, geographic region, area deprivation index, self-reported weight, and device-measured physical activity (steps per day). Results: Among 28 189 participants (median [IQR] age, 51 [43-58] years; 9424 women [40.4%]; 13 902 men [59.6%]), median (IQR) baseline systolic BP was 129.5 mm Hg (120.5-139.6 mm Hg) and diastolic BP was 81.7 mm Hg (75.7-88.4 mm Hg). Median systolic BP at 1 year improved at least 1 category for 495 of 934 participants (53.0%) with baseline elevated BP, 673 of 966 (69.7%) with baseline stage 1 hypertension, and 920 of 1075 (85.7%) with baseline stage 2 hypertension. Participants in the program for 3 years had a mean (SEM) systolic BP reduction of 7.2 (0.4), 12.2 (0.7), and 20.9 (1.7) mm Hg compared with baseline for those starting with elevated, stage 1 hypertension, and stage 2 hypertension, respectively. Greater engagement was associated with lower systolic BP over time (high-engagement group: 131.2 mm Hg; 95% CI, 115.5-155.8 mm Hg; medium-engagement group: 133.4 mm Hg; 95% CI 116.3-159.5 mm Hg; low-engagement group: 135.5 mm Hg; 95% CI, 117.3-164.8 mm Hg; P < .001); these results persisted after adjusting for age, gender, depression, anxiety, diabetes, high cholesterol, smoking, area deprivation index rank, and US region, which was partially mediated by greater physical activity. A very high BP (systolic BP >180 mm Hg) was observed 11 637 times from 3778 participants. Greater engagement was associated with lower risk of very high BP; the estimated probability of a very high BP was greater in the low-engagement group (1.42%; 95% CI, 1.26%-1.59%) compared with the medium-engagement group (0.79%; 95% CI, 0.71%-0.87%; P < .001) and the high-engagement group (0.53%; 95% CI, 0.45%-0.60%; P < .001 for comparison with both groups). Conclusions and Relevance: The findings of this study suggest that a mobile technology hypertension self-management program can support long-term BP control and very high BP detection. Such programs may improve real-world BP monitoring and control.

Home Blood Pressure Monitoring.

Home blood pressure monitoring provides important diagnostic information beyond in-office blood pressure readings and offers similar results to ambulatory blood pressure monitoring. Home blood pressure monitoring involves patients independently measuring their blood pressure with an electronic device, whereas ambulatory blood pressure monitoring involves patients wearing a portable monitor for 24 to 48 hours. Although ambulatory blood pressure monitoring is the diagnostic standard for measurement, home blood pressure monitoring is more practical and accessible to patients, and its use is recommended by the U.S. Preventive Services Task Force and the American College of Cardiology/American Heart Association. Home blood pressure monitoring generally results in lower blood pressure readings than in-office measurements, can confirm the diagnosis of hypertension after an elevated office blood pressure reading, and can identify patients with white coat hypertension or masked hypertension. Best practices for home blood pressure monitoring include using an appropriately fitting upper-arm cuff on a bare arm, emptying the bladder, avoiding caffeinated beverages for 30 minutes before taking the measurement, resting for five minutes before taking the measurement, keeping the feet on the floor uncrossed and the arm supported with the cuff at heart level, and not talking during the reading. An average of multiple readings, ideally two readings in the morning and again in the evening separated by at least one minute each, is recommended for one week. Home blood pressure readings can be used in hypertension quality measures.

Analysis of the Implementation, User Perspectives, and Feedback From a Mobile Health Intervention for Individuals Living With Hypertension (DREAM-GLOBAL): Mixed Methods Study.

BACKGROUND: DREAM-GLOBAL (Diagnosing hypertension-Engaging Action and Management in Getting Lower Blood Pressure in Indigenous and low- and middle-income countries) studied a SMS text messaging-based system for blood pressure measurement and hypertension management in Canadian Aboriginal and Tanzanian communities. The use of SMS text messages is an emerging point of interest in global health care initiatives because of their scalability, customizability, transferability, and cost-effectiveness. OBJECTIVE: The study aim was to assess the effect on the difference in blood pressure reduction of active hypertension management messages or passive health behavior messages. The system was designed to be implemented in remote areas with wireless availability. This study described the implementation and evaluation of technical components, including quantitative data from the transmission of blood pressure measurements and qualitative data collected on the operational aspects of the system from participants, health care providers, and community leadership. METHODS: The study was implemented in six remote Indigenous Canadian and two rural Tanzanian communities. Blood pressure readings were taken by a community health worker and transmitted to a mobile phone via Bluetooth, then by wireless to a programmed central server. From the server, the readings were sent to the participant's own phone as well. Participants also received biweekly tailored SMS text messages on their phones. Quantitative data on blood pressure reading transmissions were collected from the study central server. Qualitative data were collected by surveys, focus groups, and key informant interviews of participants, health care providers, and health leadership. RESULTS: In Canada, between February 2014 and February 2017, 2818 blood pressure readings from 243 patients were transmitted to the central server. In Tanzania, between October 2014 and August 2015, 1165 readings from 130 patients were transmitted to the central server. The use of Bluetooth technology enabled the secure, reliable transmission of information from participants to their health care provider. The timing and frequency were satisfactory to 137 of 187 (73.2%) of participants, supporting the process of sending weekly messages twice on Mondays and Thursdays at 11 am. A total of 97.0% (164/169) of the participants surveyed said they would recommend participation in the DREAM-GLOBAL program to a friend or relative with hypertension. CONCLUSIONS: In remote communities, the DREAM-GLOBAL study helped local health care providers deliver a blood pressure management program that enabled patients and community workers to feel connected. The technical components of the study were implemented as planned, and patients felt supported in their management through the SMS text messaging and mobile health program. Technological issues were solved with troubleshooting. Overall, the technical aspects of this research program enhanced clinical care and study evaluation and were well received by participants, health care workers, and community leadership. TRIAL REGISTRATION: Clinicaltrials.gov NCT02111226; https://clinicaltrials.gov/ct2/show/NCT02111226.

Assessment of a commercially available veterinary blood pressure device used on awake and anesthetized dogs.

OBJECTIVE: To compare results of a commercially available device for oscillometrically measured blood pressure (OBP) with invasively measured blood pressure (IBP) in awake and anesthetized dogs. ANIMALS: 19 adult dogs (mean ± SD body weight, 17.8 ± 7.5 kg). PROCEDURES: Blood pressures were measured in dogs while they were awake and anesthetized with isoflurane. The OBP was recorded on a thoracic limb, and IBP was simultaneously recorded from the median caudal artery. Agreement between OBP and IBP was evaluated with the Bland-Altman method. Guidelines of the American College of Veterinary Internal Medicine (ACVIM) were used for validation of the oscillometric device. RESULTS: In awake dogs, mean bias of the oscillometric device was -11.12 mm Hg (95% limits of agreement [LOA], -61.14 to 38.90 mm Hg) for systolic arterial blood pressure (SAP), 9.39 mm Hg (LOA, -28.26 to 47.04 mm Hg) for diastolic arterial blood pressure (DAP), and -0.85 mm Hg (LOA, -40.54 to 38.84 mm Hg) for mean arterial blood pressure (MAP). In anesthetized dogs, mean bias was -12.27 mm Hg (LOA, -47.36 to 22.82 mm Hg) for SAP, -3.92 mm Hg (LOA, -25.28 to 17.44 mm Hg) for DAP, and -7.89 mm Hg (LOA, -32.31 to 16.53 mm Hg) for MAP. The oscillometric device did not fulfill ACVIM guidelines for the validation of such devices. CONCLUSIONS AND CLINICAL RELEVANCE: Agreement between OBP and IBP results for awake and anesthetized dogs was poor. The oscillometric blood pressure device did not fulfill ACVIM guidelines for validation. Therefore, clinical use of this device cannot be recommended.

Blood pressure related to age: The India ABPM study.

The present paper reports trends in office blood pressure (BP) measurement (OBPM) and ambulatory blood pressure measurement (ABPM) with age in a large multi-center Indian all comers' population visiting primary care physicians. ABPM and OBPM data from 27 472 subjects (aged 51 ± 14 years, males 68.2%, treated 45.5%) were analyzed and compared. Individual differences between OBPM and ABPM patterns were compared for patients according to 10-year age categories. Results showed that systolic (S) BP values started to increase with age from the age of 40, BP variability (SD) increased from the age of 30 years. Diastolic (D) BP values started to decrease from the age of 50 years. Mean OBPM values were higher than daytime ABPM values (all P < .001) in all age-groups. The prevalence of white coat hypertension (WCH) and masked hypertension (MH) was based on OBPM and daytime, 24-hour, and nighttime average BPs together. WCH decreased with age from 15.1% and 12.4% in treated and untreated subjects at the youngest age to 7.2% and 6.9% in the oldest age, respectively. MH prevalence was higher for untreated than for treated subjects but remained similar for all age-groups (range of 18.6%-21.3%). The prevalence of reverse dippers increased with age from the youngest to oldest group with 7.3%-34.2% (P < .001 for trend). Dippers prevalence decreased from 42.5% to 17.9% from the youngest to oldest age-groups, respectively (P < .001 for trend). These findings confirm that BP patterns show clear differences in trends with age, particularly regarding nighttime BP.

Validation and Acceptability of a Cuffless Wrist-Worn Wearable Blood Pressure Monitoring Device Among Users and Health Care Professionals: Mixed Methods Study.

BACKGROUND: Blood pressure (BP) is an important modifiable cardiovascular risk factor, yet its long-term monitoring remains problematic. Wearable cuffless devices enable the capture of multiple BP measures during everyday activities and could improve BP monitoring, but little is known about their validity or acceptability. OBJECTIVE: This study aimed to validate a wrist-worn cuffless wearable BP device (Model T2; TMART Technologies Limited) and assess its acceptability among users and health care professionals. METHODS: A mixed methods study was conducted to examine the validity and comparability of a wearable cuffless BP device against ambulatory and home devices. BP was measured simultaneously over 24 hours using wearable and ambulatory devices and over 7 days using wearable and home devices. Pearson correlation coefficients compared the degree of association between the measures, and limits of agreement (LOA; Bland-Altman plots) were generated to assess measurement bias. Semistructured interviews were conducted with users and 10 health care professionals to assess acceptability, facilitators, and barriers to using the wearable device. Interviews were audio recorded, transcribed, and analyzed. RESULTS: A total of 9090 BP measurements were collected from 20 healthy volunteers (mean 20.3 years, SD 5.4; N=10 females). Mean (SD) systolic BP (SBP)/diastolic BP (DBP) measured using the ambulatory (24 hours), home (7 days), and wearable (7 days) devices were 126 (SD 10)/75 (SD 6) mm Hg, 112 (SD 10)/71 (SD 9) mm Hg and 125 (SD 4)/77 (SD 3) mm Hg, respectively. Mean (LOA) biases and precision between the wearable and ambulatory devices over 24 hours were 0.5 (-10.1 to 11.1) mm Hg for SBP and 2.24 (-17.6 to 13.1) mm Hg for DBP. The mean biases (LOA) and precision between the wearable and home device over 7 days were -12.7 (-28.7 to 3.4) mm Hg for SBP and -5.6 (-20.5 to 9.2) mm Hg for DBP. The wearable BP device was well accepted by participants who found the device easy to wear and use. Both participants and health care providers agreed that the wearable cuffless devices were easy to use and that they could be used to improve BP monitoring. CONCLUSIONS: Wearable BP measures compared well against a gold-standard ambulatory device, indicating potential for this user-friendly method to augment BP management, particularly by enabling long-term monitoring that could improve treatment titration and increase understanding of users' BP response during daily activity and stressors.

Assessment of a non-physician screening program for hypertension and cardiovascular risk in community pharmacies.

BACKGROUND AND AIMS: The strategic role of prevention in hypertension setting is well known but, with the only exception of annually events promoted by international scientific societies, no other screening campaigns are available. Aim of this study was to assess the feasibility of a non-physician pharmacy-based screening program and to describe the cardiovascular risk and the BP status of participating subjects. METHODS AND RESULTS: 2731 costumers participated to the screening program, answering to a questionnaire about personal cardiovascular risk and measuring their BP with an Omron HEM 1040-E. Since no threshold for hypertension diagnosis is currently available for community pharmacies BP measurements, we assessed high BP prevalence according to 3 different cut-offs (≥140/90, ≥135/85 and ≥ 130/80 mmHg) and compared normotensives and hypertensives on major cardiovascular risk factors. According to the proposed cut-offs, prevalence of hypertension was respectively of 31%, 45% and 59.5%, and it increased among younger subjects (31-65 y) when the lowest cut-offs were applied. High BP was found in a large percentage of subjects self-declared on-/not on-treatment (uncontrolled hypertensives) or normotensives (presumptive hypertensives) and among those not aware of their own BP values (presumptive hypertensives). Prevalence of CV risk factors was higher in hypertensives than in normotensives. CONCLUSIONS: Our findings demonstrated that a community pharmacy-based screening is feasible and attracts the interests of many subjects, improving awareness on their BP status. The screening was also showed to be useful in order to detect potentially uncontrolled and/or suspected new hypertensives, especially among young adults, to refer to general practitioners for confirmatory diagnosis or further evaluation.

Affordable and low-maintenance obstetric devices.

OBJECTIVE: Adequate obstetric care requires the availability of essential diagnostic and management equipment; however, for centers with budget restrictions, the acquisition and maintenance of these devices can pose major challenges. The purpose of the present paper is to disseminate knowledge about the availability of affordable and low-maintenance obstetric devices, which might help to save lives in low- and medium-resource countries. METHOD: Over the course of 2015-2018, the International Federation of Gynecology and Obstetrics (FIGO) Safe Motherhood and Newborn Health Committee acquired information from different clinical and commercial sources regarding the availability of affordable and low-maintenance essential obstetric devices. RESULTS: The Committee identified several devices that met the criteria of low cost and ease of maintenance: a winding handheld Doppler device for intermittent auscultation; a portable continuous fetal heart rate monitor; a validated semi-automated blood pressure monitor; the Foley catheter balloon for labor induction in women with an unfavorable cervix; reusable metal and plastic vacuum cups and manual pumps; an intrauterine tamponade balloon; and the non-pneumatic anti-shock garment. CONCLUSION: Several affordable and low-maintenance obstetric devices are currently available that offer the potential to save lives in resource-constrained settings.

Quality of Blood Pressure Tracking Apps for the iPhone: Content Analysis and Evaluation of Adherence With Home Blood Pressure Measurement Best Practices.

BACKGROUND: Blood pressure (BP) tracking apps may aid in hypertension (HTN) self-management, but app quality may be problematic. OBJECTIVE: This study aimed to develop a content-dependent rating system for BP tracking apps and systematically evaluate BP tracking features, content-independent quality, functional characteristics, and educational comprehensiveness of English language iPhone apps developed with the primary purpose of tracking a consumer's BP measurements. METHODS: We created a 28-item checklist reflecting overall app quality and a simplified 2-item checklist to assess adherence with home BP monitoring best practices. Apps with educational information were evaluated for comprehensiveness on a 7-point scale and for consistency with evidence-based guidelines. Higher scores represent better quality and comprehensiveness. We searched the Canadian App Store on June 28, 2016, using the keywords hypertension and blood pressure. A total of 2 reviewers independently assessed apps according to the standardized template. We determined if paid apps, educational apps, or those rated ≥4 stars were of higher quality. RESULTS: Of the 948 apps screened, 62 met the inclusion criteria. The mean overall quality score was 12.2 (SD 4.6, out of 28) and 6 apps (10%, 6/62) met the home BP monitoring best practice criteria. In all, 12 apps contained educational content (mean comprehensiveness 2.4, SD 1.6 out of 14), most commonly, background information on HTN. Apps with educational content (mean 15.1, SD 3.8 vs 11.8, SD 4.8; P=.03) or a ≥4 star rating (median 19, interquartile range [IQR] 15-20, vs 12, IQR 9-15; P=.02) had higher overall quality. CONCLUSIONS: The BP tracking apps reviewed had variable quality and few met the home BP monitoring best practice criteria. When deciding to recommend a specific BP tracking app, we suggest clinicians should evaluate whether the app allows input of duplicate BP readings in the morning and evening for at least seven days and presents the mean BP value for user-specified dates. Greater attention to home BP measurement best practices is required during app development.

Validation in the General Population of the iHealth Track Blood Pressure Monitor for Self-Measurement According to the European Society of Hypertension International Protocol Revision 2010: Descriptive Investigation.

BACKGROUND: High blood pressure is one of the most common reasons why patients seek assistance in daily clinical practice. Screening for hypertension is fundamental and, because hypertension is identified only when blood pressure is measured, accurate measurements are key to the diagnosis and management of this disease. The European Society of Hypertension International Protocol revision 2010 (ESH-IP2) was developed to assess the validity of automatic blood pressure measuring devices that are increasingly being used to replace mercury sphygmomanometers. OBJECTIVE: We sought to determine whether the iHealth Track blood pressure monitor meets ESH-IP2 requirements for self-measurement of blood pressure and heart rate at the brachial level and is appropriate for use in the general population. METHODS: This study was a descriptive investigation. ESH-IP2 requires a total number of 33 participants. For each measure, the difference between observer and device blood pressure and heart rate values is calculated. In all, 99 pairs of blood pressure differences are classified into 3 categories (≤5, ≤10, and ≤15 mm Hg), and 99 pairs of heart rate differences are classified into 3 categories (≤3, ≤5, and ≤8 beats/min). We followed these protocol procedures in a convenience sample of 33 participants. RESULTS: iHealth Track fulfilled ESH-IP2 requirements and passed the validation process successfully. We observed an absolute difference within 5 mm Hg in 75 of 99 comparisons for systolic blood pressure, 78 of 99 comparisons for diastolic blood pressure, and 89 of 99 comparisons for heart rate. The mean differences between the test and standard readings were 4.19 (SD 4.48) mm Hg for systolic blood pressure, 3.74 (SD 4.55) mm Hg for diastolic blood pressure, and 1.95 (SD 3.27) beats/min for heart rate. With regard to part 2 of ESH-IP2, we observed a minimum of 2 of 3 measurements within a 5-mm Hg difference in 29 of 33 participants for systolic blood pressure and 26 of 33 for diastolic blood pressure, and a minimum of 2 of 3 measurements within a 3-beat/min difference in 30 of 33 participants for heart rate. CONCLUSIONS: iHealth Track readings differed from the standard by less than 5, 10, and 15 mm Hg, fulfilling ESH-IP2 requirements. Consequently, this device is suitable for use in the general population.

Noninvasive assessment of blood pressure in rotary blood pump recipients using a novel ultrasonic Doppler method.

In rotary blood pump recipients with low blood pressure pulsatility, current oscillometric methods to measure blood pressure are not applicable. The aim of this study was to use ultrasonic Doppler flow measurements to determine blood pressure in this patient population noninvasively. In 28 rotary blood pump recipients, blood pressure was measured three times with the developed Doppler method and compared to the invasive arterial line (n = 15) or to the oscillometric Terumo Elemano BP monitor (n = 13). Blood velocities in the radial artery were recorded by the new Doppler sensor during cuff deflation. A sigmoid curve was fitted to a preprocessed velocity signal and the systolic and mean arterial pressures were determined. A total of 84 measurements were performed, and 17 recordings were visually excluded from further analysis due to obvious artifacts. Both the systolic and mean pressures derived by the Doppler method were in good accordance with the invasively measured pressure (3.7 ± 6.6 mmHg for the systolic and -2.1 ± 7.3 mmHg for the mean pressure). A good agreement between the oscillometric monitor and the Doppler method for the systolic (0.0 ± 6.0 mmHg) and mean (1.0 ± 5.9 mmHg) pressures was observed. In this study, a new Doppler blood pressure measurement system was developed and clinically validated. The novel sensor allows easier placement above the radial artery compared to commercial probes. An algorithm was developed which processes the Doppler signal robustly and is able to determine the systolic as well as the mean arterial blood pressure.

Intra-arterial pulse wave analysis during thrombectomy for the assessment of collateral status - A feasibility study.

PURPOSE: Knowledge of the collateralization of an occluded vessel is important for the risk-benefit analysis of difficult revascularization maneuvers during mechanical thrombectomy. If the territory behind a clot is well perfused, one could desist from performing a risky thrombectomy maneuver. The arterial pulse pressure curve may serve as an indicator for the collateralization of an occluded target vessel. We investigated the feasibility of arterial pulse measurements with a standard microcatheter. METHODS: We measured the intra-arterial blood pressure proximal and distal to the clot in 40 thrombectomy maneuvers in a porcine stroke model. We used a microcatheter (Trevo Pro 18, Stryker, Kalamazoo, CA, USA), a pressure transducer (MEMSCAP SP844), an AdInstruments Powerlab 16/35 workstation, and LabChart 8 Software (AdInstruments, Dunedin, New Zealand). RESULTS: Median arterial blood pressure proximal and distal to the clot was 96.0 mmHg (IQR, 23.8 mmHg) and 47.5 mmHg (IQR, 43.5 mmHg), respectively (p < .001). The median difference between systolic maximum and diastolic minimum proximal and distal to the clot decreased significantly from 1.8 mmHg (IQR, 3.6 mmHg) to 0.0 mmHg (IQR, 0.5 mmHg) (p < .001). There was loss of the curve in 26 of 40 cases and loss of pressure in 23 of 40 cases (p = .008). There was no significant correlation between vessel diameter and either loss of the pulse pressure curve (p = .20) or overall pressure loss (p = .31). CONCLUSION: It is possible to measure the pulse pressure proximal and distal to the clot with a standard microcatheter used during mechanical thrombectomy.

Health 2.0 2018.

Martin J. Kurian, Peter J. Rentzepis, Ann M. Carracher, and Kelly L. Close are of Close Concerns (http://www.closeconcerns.com), a healthcare information company focused exclusively on diabetes and obesity care. Close Concerns publishes Closer Look, a periodical that brings together news and insights in these areas. Each month, the Journal of Diabetes includes this News feature, in which Kurian, Rentzepis, Carracher, and Close review the latest developments relevant to researchers and clinicians.

Endovascular treatment of transplant renal artery stenosis based on hemodynamic assessment using a pressure wire: a case report.

BACKGROUND: Transplant renal artery stenosis (TRAS) is a serious complication after renal transplantation, leading to hypertension, deterioration in renal function, and/or graft loss. The incidence of TRAS reportedly varies from 1 to 23%, depending on its definition or diagnostic tools. The hemodynamic definition or therapeutic indication of TRAS is unclear. CASE PRESENTATION: A 66-year-old man with a history of diabetes, chronic kidney disease, and angina presented with a 2-week history of dyspnea and leg edema. He had undergone living-donor kidney transplantation for end-stage renal disease secondary to diabetic nephropathy 7 years earlier. He developed acute deterioration in renal function after the administration of an angiotensin II receptor blocker and required emergency hospitalization owing to acute congestive heart failure with pulmonary edema. A vasodilator and loop diuretics were administered following his admission, and the patient's symptoms resolved quickly. Further investigation, including magnetic resonance angiography and ultrasonography, revealed severe stenosis of the transplant renal artery. Renal arteriography and pressure gradient measurement using a 0.014-inch pressure wire were performed. The systolic pressure gradient was 40 mmHg, and the resting Pd/Pa ratio (ratio of mean distal to lesion and mean proximal pressures) was 0.90 without hyperemia. Hemodynamically significant stenosis was suspected. Intravascular ultrasonography revealed vessel shrinkage in the stenotic area, suggestive of the end-to-end anastomosis site. Pre-dilation using a 4-mm balloon, implantation of a 6-mm self-expandable stent, and post-dilatation using a 5-mm balloon were performed. Although the moderate stenosis persisted angiographically, the systolic pressure gradient dropped to 20 mmHg with the mean systolic pressure ratio increased to 0.95, which was considered an acceptable result. One month after the procedure, the patient's renal function and blood pressure control had significantly improved. CONCLUSIONS: Hemodynamic assessment using a pressure wire is useful in determining the appropriate therapeutic indication and endpoint of endovascular treatment of TRAS.

Wideband External Pulse Recorded During Cuff Blood Pressure Measurement: A New Technique for Cardiovascular Assessment.

INTRODUCTION: The wideband external pulse (WEP) recorded during blood pressure measurement reveals three components (K1, K2, K3). K1 is recorded with cuff pressure (CP) above systolic (SP). AIM: To assess whether the K1 pattern contains information about the functional and structural properties of the cardiovascular system. METHODS: WEP analysis, echocardiography, carotid artery (CA) ultrasonography and applanation tonometry were conducted on 178 hypertensives. K1R, a feature of K1, was defined to provide a measure between the arterial incident and backward reflective waves. RESULTS: K1R was strongly correlated to vascular functional and structural parameters compatible with vascular effects of aging and hypertension. ANOVA analysis (K1R < 0 vs K1R > 0) showed that K1R < 0 participants: (1) were older, shorter, weighed less, had a smaller body surface area; (2) had higher SP, pulse (PP) and mean (MP) pressure, lower heart rate (HR), greater total peripheral resistance (TPR), lower cardiac output (CO), and a stiffer arterial system; (3) had a greater left ventricular (LV) relative wall thickness (LVRWT), carotid artery (CA) relative wall thickness (CARWT), CA far-wall intima-media thickness at end diastole (CIMTd) and CA cross-sectional area (CSA) (all p < 0.001). Regressions revealed that age, TPR, SP, gender, and HR predicted K1R (R2 = 0.64) and that PP and K1R predicted CARWT (R2 = 0.14). Logistic regression revealed that age, TPR, SP and aortic diameter differentiated K1R < 0 from K1R > 0 (Nagelkerke R2 = 0.77). CONCLUSIONS: K1R is related to vascular functional properties, with suggestive evidence that K1R is also related to vascular structural properties and perhaps subsequent cardiovascular risk.

Hypertension Canada's 2018 Guidelines for the Management of Hypertension in Pregnancy.

We present Hypertension Canada's inaugural evidence-based Canadian recommendations for the management of hypertension in pregnancy. Hypertension in pregnancy is common, affecting approximately 7% of pregnancies in Canada, and requires effective management to reduce maternal, fetal, and newborn complications. Because of this importance, these guidelines were developed in partnership with the Society of Obstetricians and Gynaecologists of Canada with the main common objective of improving the management of women with hypertension in pregnancy. Guidelines for the diagnosis, assessment, prevention, and treatment of hypertension in adults and children are published separately. In this first Hypertension Canada guidelines for hypertension in pregnancy, 7 recommendations for the management of nonsevere and severe hypertension in pregnancy are presented. For nonsevere hypertension in pregnancy (systolic blood pressure 140-159 mm Hg and/or diastolic blood pressure 80-109 mm Hg), we provide guidance for the threshold for initiation of antihypertensive therapy, blood pressure targets, as well as first- and second-line antihypertensive medications. Severe hypertension (systolic blood pressure ≥ 160 mm Hg and/or diastolic blood pressure ≥ 110 mm Hg) requires urgent antihypertensive therapy to reduce maternal, fetal, and newborn adverse outcomes. The specific evidence and rationale underlying each of these guidelines are discussed.

Hypertension Canada's 2018 Guidelines for Diagnosis, Risk Assessment, Prevention, and Treatment of Hypertension in Adults and Children.

Hypertension Canada provides annually updated, evidence-based guidelines for the diagnosis, assessment, prevention, and treatment of hypertension in adults and children. This year, the adult and pediatric guidelines are combined in one document. The new 2018 pregnancy-specific hypertension guidelines are published separately. For 2018, 5 new guidelines are introduced, and 1 existing guideline on the blood pressure thresholds and targets in the setting of thrombolysis for acute ischemic stroke is revised. The use of validated wrist devices for the estimation of blood pressure in individuals with large arm circumference is now included. Guidance is provided for the follow-up measurements of blood pressure, with the use of standardized methods and electronic (oscillometric) upper arm devices in individuals with hypertension, and either ambulatory blood pressure monitoring or home blood pressure monitoring in individuals with white coat effect. We specify that all individuals with hypertension should have an assessment of global cardiovascular risk to promote health behaviours that lower blood pressure. Finally, an angiotensin receptor-neprilysin inhibitor combination should be used in place of either an angiotensin-converting enzyme inhibitor or angiotensin receptor blocker in individuals with heart failure (with ejection fraction < 40%) who are symptomatic despite appropriate doses of guideline-directed heart failure therapies. The specific evidence and rationale underlying each of these guidelines are discussed.

Evaluation of a novel device for the management of high blood pressure and shock in pregnancy in low-resource settings: study protocol for a stepped-wedge cluster-randomised controlled trial (CRADLE-3 trial).

BACKGROUND: Obstetric haemorrhage, sepsis and pregnancy hypertension account for more than 50% of maternal deaths worldwide. Early detection and effective management of these conditions relies on vital signs. The Microlife® CRADLE Vital Sign Alert (VSA) is an easy-to-use, accurate device that measures blood pressure and pulse. It incorporates a traffic-light early warning system that alerts all levels of healthcare provider to the need for escalation of care in women with obstetric haemorrhage, sepsis or pregnancy hypertension, thereby aiding early recognition of haemodynamic instability and preventing maternal mortality and morbidity. The aim of the trial was to determine whether implementation of the CRADLE intervention (the Microlife® CRADLE VSA device and CRADLE training package) into routine maternity care in place of existing equipment will reduce a composite outcome of maternal mortality and morbidity in low- and middle-income country populations. METHODS: The CRADLE-3 trial was a stepped-wedge cluster-randomised controlled trial of the CRADLE intervention compared to routine maternity care. Each cluster crossed from routine maternity care to the intervention at 2-monthly intervals over the course of 20 months (April 2016 to November 2017). All women identified as pregnant or within 6 weeks postpartum, presenting for maternity care in cluster catchment areas were eligible to participate. Primary outcome data (composite of maternal death, eclampsia and emergency hysterectomy per 10,000 deliveries) were collected at 10 clusters (Gokak, Belgaum, India; Harare, Zimbabwe; Ndola, Zambia; Lusaka, Zambia; Free Town, Sierra Leone; Mbale, Uganda; Kampala, Uganda; Cap Haitien, Haiti; South West, Malawi; Addis Ababa, Ethiopia). This trial was informed by the Medical Research Council guidance for complex interventions. A process evaluation was undertaken to evaluate implementation in each site and a cost-effectiveness evaluation will be undertaken. DISCUSSION: All aspects of this protocol have been evaluated in a feasibility study, with subsequent optimisation of the intervention. This trial will demonstrate the potential impact of the CRADLE intervention on reducing maternal mortality and morbidity in low-resource settings. It is anticipated that the relatively low cost of the intervention and ease of integration into existing health systems will be of significant interest to local, national and international health policy-makers. TRIAL REGISTRATION: ISCRTN41244132. Registered on 2 February 2016. Prospective protocol modifications have been recorded and were communicated to the Ethics Committees and Trials Committees. The adapted Standard Protocol Items: Recommendations for Interventional Trials (SPIRIT) Checklist and the SPIRIT Checklist are attached as Additional file 1.