Pressure Management Research Articles

The optimal management of arterial blood pressure in acute stroke: A never-ending conundrum

The optimal management of arterial blood pressure in acute stroke: A never-ending conundrum

Coordinated management of oxygen excess ratio and cathode pressure for PEMFC based on synthesis variable-gain robust predictive control

In this research endeavor, a novel synthesis variable-gain robust model predictive control (SVGRPC) method using the min-max technique with parameter dependent Lyapunov functions is introduced to achieve the desired trajectory tracking of oxygen excess ratio (OER) and cathode pressure in the polymer electrolyte membrane fuel cells (PEMFCs) system. Initially, a simplified control-oriented model of the air supply system is developed and then transformed into a polytopic form to accommodate the inherent uncertainties in the PEMFC. Subsequently, the polytopic model is integrated with the reference trajectory to construct an augmented state-space model for deriving an error state representation. In the framework of robust model predictive control (RPC) utilizing a parameter-dependent Lyapunov function, a series of variable feedback gains are employed to mitigate conservatism. Additionally, the online solution process imposes a significant computational burden, presenting challenges for the real-time implementation of RPC-based control strategy. Therefore, the offline computing is introduced to significantly reduce the computational burden, resulting in the development of the SVGRPC strategy proposed in this paper. Subsequently, the SVGRPC strategy computes explicit linear state-feedback control laws by solving linear matrix inequalities (LMIs) using an offline control algorithm. The effectiveness of the proposed controller is then validated through assessments conducted under three distinct operating conditions of the PEMFC system. The outcomes of this study affirm that the proposed controller improves the requirements of control performance when compared to the online RPC with a quadratic Lyapunov function while significantly alleviating the computational workload.

Smart management of pressure regulating stations to maximize hydrogen injection in a gas distribution network

Gas distribution networks traditionally maintain constant pressure setpoints at regulating stations, ensuring a consistent supply to end-users with a high safety margin. However, the prospect of hydrogen injection in the gas networks necessitates rethinking operational strategies. This study examines the environmental and fluid-dynamic implications of implementing a smart pressure management approach in regulating stations within a distribution network with a localized hydrogen injection. The research introduces a novel simulation-based optimization algorithm, incorporating a steady-state fluid-dynamic model with hydrogen tracking, used to optimize the pressure setpoints in the stations. The algorithm is applied to a two-pressure levels looped gas network with multiple gas supply nodes and a single hydrogen injection. The test case results reveal that utilizing dynamic pressure setpoints leads to a 22% increase in hydrogen penetration compared to standard operation. Therefore, this study highlights that smart pressure modulation in a gas network with hydrogen injection can unlock a latent decarbonization potential, while simultaneously adhering to safety limits.

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Evidence-Based Practice: From NIHSS Updates to Stroke Navigation, Blood Pressure Management, and Educational Best Practices

Evaluation of Knowledge among Nurses about Pressure Ulcer in a Tertiary Care Hospital, Lahore

Background: Pressure ulcers are a prevalent issue in healthcare settings, leading to significant morbidity and increased healthcare costs. Nurses play a crucial role in the prevention and management of these conditions, yet gaps in knowledge can affect patient outcomes. The study aimed to assess the knowledge of nurses at a tertiary care hospital in Lahore, Pakistan, a setting where pressure ulcer management is critical yet understudied. Objective: This study aimed to evaluate the current level of knowledge among nurses regarding pressure ulcer prevention and management, and to identify any significant differences in knowledge across various critical care settings within the hospital. Methods: A cross-sectional descriptive study was conducted at Shalamar Hospital, Lahore, involving 125 staff nurses and nursing interns selected via simple random sampling. Participants were required to have at least six months of experience in general wards. Data were collected using a validated questionnaire, assessing knowledge of pressure ulcer management. Ethical approval was obtained from the Shalamar College of Nursing's ethical committee. Data analysis was performed using SPSS version 25 and Microsoft Excel, applying descriptive and inferential statistics, including the Chi-square test, with a significance level set at p<0.05. Results: The study revealed that 68.8% (86/125) of nurses had average knowledge, 29.6% (37/125) demonstrated good knowledge, and only 1.6% (2/125) exhibited poor knowledge regarding pressure ulcer management. Notably, nurses in the Surgical Intensive Care Unit (SICU) and High Dependency Unit (HDU) displayed the highest levels of knowledge, whereas those in the Medical Intensive Care Unit (MICU), Cardiac Care Unit (CCU), and Emergency Room (ER) had comparatively lower knowledge levels. Conclusion: The majority of nurses at Shalamar Hospital possessed an average level of knowledge concerning pressure ulcer management. There is a critical need for targeted educational interventions to enhance knowledge and practices, particularly in units where nurses showed lower knowledge levels. Improving nurse education in pressure ulcer management could significantly impact the quality of patient care and reduce the prevalence of these injuries.

“Advocates for Each Other”: The creation and evaluation of a pragmatic peer navigation program for black patients in primary care with uncontrolled hypertension

BackgroundBlack individuals in the U.S. and in our primary care clinic experience worse control of blood pressure compared to White individuals. ObjectiveTo address this inequity, our objectives were to (1) elicit from patients and community members their ideas for barriers and facilitators to blood pressure control; and (2) use their input to design and pilot a navigator program for Black patients in our clinic to improve blood pressure management. Patient involvementWe conducted three focus groups with 27 individuals and identified two main areas of need that informed the peer navigator program: (1) community-based services and (2) skill development for hypertension self-management. MethodsPeer navigators from the Black community called participants at least monthly for 6–12 months and connected them with medical and social services. Available blood pressure data was used as the primary outcome to measure change pre- to post-peer navigation program. ResultsAmong 499 eligible patients in the clinic, 53 (10.6%) enrolled in the peer navigation program. For those with baseline and follow-up blood pressure data, mean systolic blood pressure decreased from 155.9 to 142.4 mmHg after the program (change of −13.6, 95% CI −24.7 to −2.4) for the enrolled patients (N = 17) and from 139.1 to 137.1 mmHg (change of −2.5, −4.8 to 1.9) for unenrolled, comparison patients (N = 183). DiscussionThis community-informed peer navigation program to support Black patients with uncontrolled hypertension led to a 11.1 mmHg greater decrease in average systolic blood pressure for enrolled patients compared to the comparison group. However, the enrolled group started with a significantly higher systolic blood pressure at baseline with more room for improvement. While this study was conducted during the pandemic years, low uptake of this program needs to be addressed in expansion efforts. Practical valueClinic-based peer navigation for hypertension improved blood pressure control and was highly regarded by the subset of enrolled patients. Increasing uptake and sustainable funding for non-billable clinic roles remain areas of need. FundingGrant from the Pacific Hospital Preservation & Development Authority.

Integrity assessment of shale gas wells in Changning Block based on hierarchical analysis method

The integrity of shale gas wells is crucial in ensuring safety and efficiency throughout the development process. Such integrity spans the entire process of drilling and fracturing horizontal wells and is an essential indicator for ensuring safe and stable production throughout the lifespan of the well. This study investigates methods for assessing the integrity of shale gas wells by employing the analytic hierarchy process combined with experimental data to establish evaluation criteria and weights. The assessment is carried out specifically on shale gas wells in Changning Block. Results indicate that the integrity of these shale gas wells is influenced by various factors, such as drilling and fracturing processes. Moreover, the integrity assessment of indicators such as oil layer casing/technical casing, liquid carrying capacity, and tube column deformation is relatively low, indicating a need for enhanced monitoring and management. The comprehensive evaluation results indicate that, overall, the integrity rating of shale gas wells is generally considered “common,” but some potential safety hazards still remain that require timely attention and resolution. Case analysis reveals varying levels of integrity risks in shale gas wells. Case 1’s score of 93.51 warrants attention but is still deemed generally safe. However, Case 2’s score of 73.89 indicates a disaster level, emphasizing urgent intervention needs. Critical factors such as pressure, cementation quality, and corrosion demand proactive management for safe, sustainable operations.

Abstract PO2-22-09: The impact of blood loss and blood pressure management in DIEP flap surgery– a retrospective analysis of 206 patients

Abstract Introduction: Autologous breast reconstruction using the deep inferior epigastric perforator flap has excellent success rates and a natural aesthetic result. Therefore, this method and its management are of great importance in modern oncoplastic surgery. In particular, women who have undergone radiation therapy after mastectomy benefit from this satisfactory and usually uncomplicated method of breast reconstruction. To achieve a desirable outcome, the effects of blood loss and blood pressure management may play an important role. In this analysis, we hypothesize that neither postoperative blood pressure management (using catecholamines) nor the amount of blood loss (defined by the median hemoglobin level difference) will worsen the surgical outcome or increase the complication rate. Patients and Methods: We performed a multicenter, multisurgeon retrospective analysis with the following primary end points: intraoperative blood loss and postoperative blood pressure management. Secondary endpoints included serious complications including flap loss and minor complications. Patients (n=194) were included from 2014-2018 at St. Antonius Hospital in Eschweiler and from 2016 to July 2018 at the Cologne Municipal Breast Cancer Center in Holweide. Patients underwent either unilateral (n=180) or bilateral (n=13) breast reconstructions with DIEP flaps, resulting in a total of n=206 cases. The subgroup regarding blood pressure management was defined by cohorts with or without catecholamine administration and included all n=206 cases. Blood loss was defined by median hemoglobin level difference and could be calculated in n=199 cases. The cohorts of the two subgroups were comparable. Results: Six flap losses were detected in a total of 206 cases (2.9%). The distribution of flap losses in the blood pressure management subgroup was not statistically significant (p=.67), while the test was not available for the blood loss subgroup. Furthermore, the analysis showed that there were no significant differences in the rates of overall complications related to the amount of blood loss intraoperatively (p= .06) or blood pressure management postoperatively (p= .19). Conclusion: DIEP flap surgery is a safe method for autologous breast reconstruction, independent of blood loss and blood pressure management. Citation Format: Hanna Fritsch, Cosima Schreiber, Wolfram Malter, Matthias Warm, Max Zinser, Alexander Bach, Christian Eichler. The impact of blood loss and blood pressure management in DIEP flap surgery– a retrospective analysis of 206 patients [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO2-22-09.

Association of metabolic syndrome and its components with hearing loss in low-income women: A population-based cross-sectional study

BackgroundHearing loss (HL) is globally prevalent among older adults and a common disability cause. Metabolic syndrome (MetS) is a complex disorder characterized by high blood pressure, high blood sugar, excess fat around the waist, and abnormal cholesterol or triglyceride levels. Few studies have examined the association between MetS and HL in women. This study investigated the association between HL and metabolic disease among low-income population women in China. MethodsThis population-based cross-sectional study was conducted between September and November 2013. All participants completed questionnaires, physical examinations, laboratory examinations, and hearing tests. HL was measured using pure-tone audiometry, and audiologists determined the final diagnoses. ResultsA total of 1448 women were enrolled, including 781 (53.9 %) with demonstrated HL and 804 (55.5 %) with MetS. Elevated blood pressure (BP) and fasting blood glucose (FBG) levels were independent risk factors for pure-tone averages (PTAs) in the high pure tone audiometry (high-PTA) group, after adjusting for education level, smoking and drinking status, body mass index group, and low high-density lipopolysaccharide cholesterol levels (all, P < 0.05); PTAs increased by 2.11 dB HL of hearing level in patients with elevated BP compared with normal BP (95 % confidence interval [CI], 0.22–4.01; P = 0.029); PTAs increased by 1.64 dB HL of hearing level (95 % CI, 0.12–3.15; P = 0.034) in patients with elevated FBG levels compared with normal FBG levels. ConclusionThese results indicate that hypertension and hyperglycemia are influencing factors for HL, and strengthening the management of blood glucose and blood pressure in community populations can reduce the burden of HL.

ANALYSIS OF THE MEDIATING EFFECT OF NONTRADITIONAL LIPID PARAMETERS IN THE RELATIONSHIP BETWEEN BODY MASS INDEX AND BLOOD PRESSURE IN CHINESE ADOLESCENTS

Objective: To analyze the mediating role of non-traditional lipid parameters in the relationship between body mass index (BMI) and blood pressure in children and adolescents, and to provide a reference basis for the development of hypertension prevention and treatment strategies in children and adolescents. Design and method: A stratified whole-group random sampling method was used to select 1796 children and adolescents aged 12 to 18 years from middle and high schools in Ningxia for physical examination and laboratory testing, and a mediating effect model was used to analyze the mediating effect of nontraditional lipids on the relationship between BMI and blood pressure. Results: Among the nontraditional lipid parameters, all of them were significantly associated with blood pressure except Non-HDL-C (all P&lt;0.001); three of them, Remnant Cholesterol (RC), TG/HDL-C and RC/HDL-C, had significantly higher effects on blood pressure than the others (all P&lt;0.001). HDL-C, RC and RC/HDL-C partially mediated the relationship between BMI and blood pressure, with the three mediating effects accounting for 5.2%, 6.9%, and 7.5% of the relationship between BMI and diastolic blood pressure and 4.4%, 3.0%, and 3.8% of the relationship between BMI and systolic blood pressure, respectively (all P&lt;0.001). Conclusions: Nontraditional lipid parameters are associated with blood pressure and partially mediate the relationship between BMI and blood pressure, and more attention should be paid to the role of monitoring nontraditional lipid parameters in the management of blood pressure in children and adolescents.

Investigating the Influence of Sex Hormones on OLFR558

Premenopausal women have blood pressure that is ~10mmHg lower than age-matched men. Women incur cardiovascular disease risk at lower blood pressures than men, implying that this sex difference in blood pressure is functionally important; however, clinical management of blood pressure is identical in men and women (Ji et al Circulation 2021). Recently, a study from our lab examined an olfactory receptor (OLFR558) that is expressed in renal juxtaglomerular cells, as well as in all renal blood vessels and a subset of extrarenal blood vessels. We find that OLFR558 is required for sex differences in blood pressure, as sex differences in blood pressure are entirely absent in Olfr558 knockout mice (Xu et al BioRxiv 2022). However, there is a gap in our knowledge regarding how OLFR558 influences blood pressure, and, in the mechanism underlying the blood pressure differences between the sexes. We hypothesize that sex hormones act to modulate OLFR558 signaling. To pursue this, we examined whether sex hormones may act as agonists or antagonists of OLFR558; in parallel, we also examined the human ortholog of OLFR558 (OR51E1). Green Up cADDis cyclic AMP assays were performed (olfactory receptors elevate cAMP upon activation) in technical triplicates, and each experiment was repeated four times. A known agonist (butyrate) activated OLFR558 at 0.5mM (0.175±0.035 cAMP production ± SD), 1mM (0.208±0.038), 2mM (0.264±0.014) and 5mM (0.238±0.028) vs baseline (0.061±0.009); all comparisons significant vs baseline by one-way ANOVA, p&lt;0.0001. We first tested estrone (E1), estradiol (E2), estriol (E3), progesterone (P), testosterone (T), follicle stimulating hormone (FSH), and luteinizing hormone (LH) as potential agonists for OLFR558. We find that none of these compounds activate OLFR558 (p values vs baseline/PBS: 50 nM estrogen: E1, p&gt;0.999; E2, p=0.999; E3, p=0.938 35nM T: p&gt;0.999, 50 nM P: p&gt;0.999, 10 mIU FSH: p=0.9348, 100 mIU FSH: p-value=0.8429, 10 mIU LH: p value &gt;0.999, 56 mIU LH: p value&gt; 0.999). We then tested these compounds as potential antagonists for OLFR558 by measuring cAMP responses to butyrate in the presence of each hormone. Estrogen, P, and T were tested at two different butyrate doses (0.1mM and 0.2 mM), and LH and FSH were tested at four different butyrate doses (0.5mM, 1mM, 2mM, and 5mM). We find that estrogen and T do not act as antagonists (p-value vs. matched doses of butyrate alone are 0.650-0.725 for 50 nM estrogen, 0.625-0.653 for 50 nM P and 0.708-0.883 for 35 nM T). Similarly, we find that LH and FSH do not antagonize OLFR558 at any of the four butyrate doses tested (p value for hormone+butyrate vs. matched doses of butyrate alone is p-value 0.4275-0.9069 for 10 mIU LH, p-value 0.5225-0.9921 for 56mIU LH, p-value 0.1235-0.9732 for 10mIU FSH, and p-value 0.5610-0.9358 for 100 mIU FSH). Similarly, we find that the human ortholog OR51E1 is significantly activated by known ligand butyrate (0.5 mM: 0.176± 0.011 cAMP production ± SD, 1mM: 0.225±0.001, 2mM: 0.242±0.027, 5mM:0.249±0.021 versus baseline 0.087±0.003 by one-way ANOVA, p&lt;0.0001), but is neither agonized nor antagonized by estrogen, P, T, LH or FSH. Looking ahead, we plan to investigate additional sex hormones and related metabolites, as well as alternative explanations for the phenotype. Better understanding of the relationship between sex hormones, blood pressure, and OLFR558/OR51E1 is pertinent to how physicians treat elevated blood pressure in men and women. Funding: American Heart Association Established Investigator Award (to JLP) and R21AG081683 (to JLP). ADM is supported by NIH PREP grant R25GM109441. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

RATIONALE AND DESIGN OF PHASE 3 TRIAL FOR BAXDROSTAT, A NOVEL HIGHLY SELECTIVE ALDOSTERONE SYNTHETASE INHIBITOR

Objective: Aldosterone is a key driver of cardiorenal disease as well as hard-to-treat hypertension. Highly selective aldosterone synthase inhibitors (ASI) are a new class of anti-hypertensive therapy that hold great promise for management of blood pressure (BP), having demonstrated BP lowering in a proof-of-concept study. The rationale for and design of a phase 3 trial with the novel ASI baxdrostat are described here. Design and method: The international, multicenter, randomized, double-blind, placebo-controlled phase 3 BaxHTN trial (NCT06034743) will enroll approximately 720 adults with uncontrolled or resistant hypertension defined as seated office systolic BP greater than/equal to 135 mmHg despite 2+ antihypertensives including a diuretic, serum potassium 3.5-5.0 mmol/L, and eGFR greater than/equal to 45mL/min/1.73m2. Given the need to address long-term efficacy but limit placebo use due to the risks of uncontrolled hypertension, the study will have 4 sequential parts following placebo run-in: 1) 12-week double-blind period, 1:1:1 randomization to baxdrostat 2 mg, baxdrostat 1 mg, or placebo; 2) 12-week open label period, re-randomization of the placebo and 1 mg arms to 2 mg or standard-of-care; 3) 8-week randomized withdrawal period to 2 mg or placebo; and 4) 20-week open label period. The primary endpoint will be the change in office systolic BP from baseline to 12 weeks. Adverse events will be evaluated under independent data monitoring committee supervision. Results: Results are expected in late 2025. Conclusions: The phase 3 BaxHTN trial design will allow assessing the safety of baxdrostat and its effect on BP in patients with uncontrolled or resistant hypertension. Results are expected in late 2025.

SINGLE-PILL COMBINATION ANTIHYPERTENSIVE THERAPY IN HYPERTENSIVE, OBESE PATIENTS: A PROSPECTIVE, EPIDEMIOLOGICAL STUDY IN ROMANIA

Objective: To assess the blood pressure (BP) management in obese, hypertensive patients under treatment with single-pill combination (SPC) antihypertensive therapy. Design and method: Prospective, observational, multicenter study, involving 192 investigators (85 cardiologists and 107 general practitioners) randomly selected from Romanian healthcare system, which included 1299 obese, hypertensive patients (Body Mass Index (BMI) of 30 kg/m2 or higher); 56.22±11years; 53.89% females) (1-month recruitment). The total study duration was 5 months (May-Aug 2023), while the patient observational period was 12 weeks (including 3 visits: baseline, at one month and at three months after inclusion). At enrolment visit each patient received a SPC antihypertensive therapy as per investigator’s decision, based on his/her own best medical judgement and in line with the current practice guidelines. Demographic data, comorbidities and data regarding hypertension and evolution of BP values in relation to the antihypertensive treatments were collected. Results: The study population had the following characteristics: BMI 34.35±4.21 kg/m2; 20.94% smokers, 56.81% with CV family history, and 52.12% had comorbidities. Among the patients with comorbidities the most frequently identified were diabetes mellitus type 2 (37.37%), valvular heart disease (20.97%), angina (19.35%) and heart failure (16.24%). At study inclusion the investigators’ perception regarding the cardiovascular (CV) risk was that only 27.02% of patients are in “very high” risk category, while according to SCORE2 and SCORE2-OP the actual calculated CV “very high” risk, was identified in 68.82% of patients. The most frequent recommended double SPC at study inclusion were perindopril/indapamide (81.68%) and olmesartan/amlodipine (5%). Hypertension was treated in all patients and systolic and diastolic BP values (SBP and DBP) and heart rate (HR) decreased significantly throughout the study (p&lt;0.001) (Fig. 1). Analyzing the patients treated with different double SPC a significant decrease in BP and HR values was observed (p&lt;0.001) for the perindopril/indapamide SPC, and olmesartan/amlodipine, respectively (Fig. 2). Conclusions: This study showed that single pill antihypertensive combinations are effective in decreasing BP and HR values in hypertensive obese patients, while correct CV risk estimation by clinicians remains challenging in their daily practice, with the tendency of underestimation.

SEX DIFFERENCES IN HYPERTENSION PREVALENCE, TREATMENT AND CONTROL IN OLDER PEOPLE IN GERMANY: RESULTS OF THE NATINAL EXAMINATION SURVEY GESUNDHEIT 65+

Objective: As hypertension is closely linked to cardiovascular events, blood pressure (BP) levels and management in populations are a vital public health concern. A gender gap with higher awareness, treatment and control of hypertension in women, especially in younger women, has been repeatedly reported. We analyze recent national BP data of the Gesundheit 65+ study in older and very old men and women in Germany 2022-2023. Design and method: Nationally representative examination survey of the population aged 65 years and older residing in Germany. We analysed self-reported hypertension diagnoses, the mean of the second and third standardized oscillometric BP measurements (Mobil-O-Graph) with one of five cuffs according to upper arm circumference and Anatomical Therapeutic Chemical- (ATC) coded medication in the past 7 days. Hypertension was defined as mean systolic BP (SBP) at or above 140 mm Hg, or mean diastolic BP (DBP) at or above 90 mm Hg, or use of antihypertensives (ATC-codes C02 antihypertensives, C03 diuretics, C07 beta-blockers, C08 calcium-channel blockers or C09 ACEI and ARB) in participants with self-reported hypertension diagnosis. Awareness was defined as self-reported BP diagnosis in those with hypertension according to study definition. Provisional population weights were used. Results: BP was measured and hypertension status defined in 743 men and 686 women aged 65 to 100 years. The prevalence of hypertension according to our study definition was 58.3% [95% CI 53.2-63.3] in men and 59.5% [53.8-64.9] in women. There were no sex differences in awareness among hypertensives (men 81.7%, women 81.2%), nor in treatment among aware hypertensives (97.5% in men and women). However, control among treated hypertensives differed considerably: while 75.7% [69.2; -81.2] of men with treated hypertension had BP at or below 140/90, control among treated in women was only at 61.4% [54.2-; 68.1]. Conclusions: Our 2022-2023 national blood pressure data of people aged 65 years and older in Germany suggest a new gender gap with less hypertension control in older women compared to older men which was not yet apparent a decade ago and stands in contrast to findings in younger adults across many studies.

Antigen-Independent Activation of CD8 T Cells Promotes Salt Sensitive Hypertension

While CD8+ T cells (CD8Ts) have recently emerged as key players in hypertension, the precise mechanisms underlying their involvement remain incompletely understood. Our previous research uncovered the critical role of CD8T activation during the initial phase of blood pressure elevation, facilitating their direct interaction with the distal convoluted tubule (DCT) via the interferon-gamma (IFNγ)-PDL1 pathway. Importantly, we have now discovered that CD8T activation during this early phase occurs in an antigen-independent manner. In this study, we delve into the contribution of the P2X7 receptor to CD8T activation and its subsequent promotion of sodium retention in the kidney. We hypothesize that blocking this receptor on CD8Ts will disrupt CD8T-tubular interaction and lead to a reduction in blood pressure. To investigate whether CD8T activation in hypertension necessitates T cell receptor (TCR) stimulation, we employed Rag2−/−/OT1mice, which exclusively harbor transgenic OT1 CD8Ts, recognizing only ovalbumin peptides but not other antigens. These mice, without any exposure to ovalbumin, were induced to develop hypertension through the DOCA + salt (DOCA) model. Blood pressure was monitored using radio-biotelemetry, and CD8T activation was confirmed using flow cytometry. In our in-vitro studies, CD8Ts were obtained from both WT and P2X7 KO mice and stimulated with BZATP or ATP. The endpoints include calcium influx (measured via the intracellular calcium indicator Fluo-4), IFNγ transcription, and glycolytic activity (assessed by Seahorse metabolic flux analyzer) as indicators of activation. To validate our findings in an in-vivo context, we measured the activation profiles of CD8Ts obtained from WT and P2X7 KO mice subjected to sham or DOCA treatment, employing RT-PCR and flow cytometry. Additionally, we conducted an adoptive transfer experiment, transferring naïve WT CD8Ts to P2X7 KO mice undergoing DOCA treatment. Blood pressure was consistently monitored via radio-biotelemetry. Our observations revealed that CD8Ts from Rag2−/−/OT1 mice become activated in response to the DOCA pressor, leading to increased IFNγ production and contributing to salt-sensitive hypertension, even in the absence of TCR-mediated antigen stimulation. Agonists of the P2X7 receptor, such as BZATP and ATP, elicited calcium influx in CD8Ts, upregulated IFNγ transcription, and enhanced glycolytic activity, all indicative of T cell activation. Furthermore, CD8Ts pre-stimulated with the P2X7 agonist BZATP displayed increased tubular PDL1 expression and sodium retention in our co-culture model when compared to naïve CD8Ts. Notably, DOCA-treated P2X7 KO CD8Ts were unable to induce an increase in blood pressure in our adoptive transfer model. However, transferring sham WT CD8Ts to DOCA-treated P2X7 KO mice successfully restored hypertension to WT levels. Our findings suggest a novel mechanism in which P2X7 receptor stimulation contributes to CD8T activation in the pathogenesis of hypertension. The deficiency of this receptor on CD8Ts prevents their activation by ATP, resulting in attenuated blood pressure elevation. As such, the CD8T P2X7 receptor presents itself as a promising target for the improvement of blood pressure management. Funding: NIH R01-HL146713, AHA 23TPA1076467. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Effectiveness of Applying Green Heart, a Smartphone-Based Self-management Intervention to Control Smoking: A Randomized Clinical Trial.

Cardiovascular diseases (CVDs) pose a significant global health concern and are the most common cause of death and disability, necessitating preventive interventions targeting modifiable risk factors. Recently, mobile-health technology has been developed to improve the delivery of cardiovascular prevention by risk factor modification. The "Green Heart" mobile application (app) was designed to aid in risk factor control among coronary artery disease (CAD) patients. This parallel-group, single-blinded randomized controlled trial enrolled 1590 CAD patients, including 668 current smokers, randomly assigned to control (paper-based education) and intervention (application-based) groups. The app encompassed three modules targeting smoking cessation, dyslipidemia control, and blood pressure management. This study evaluated the impact of the smoking cessation module on behavioral change among current smokers. Green Heart assesses nicotine dependence, offering personalized quit plans, educational content, motivational messages, and automated progress tracking. The odds of smoking behavior changes during the 24-week follow-up underwent assessment. The intention-to-treat analysis highlighted significantly elevated rates of smoking cessation and reductions in the intervention group versus the control group. Adherence to the app (per-treatment analysis) also demonstrated significantly more favorable smoking behavior changes among the application users. Logistic regression emphasized higher odds of quitting and reduction in smoking in the application group, showing an odds ratio of 2.14 (95% CI: 1.16-3.97) compared to those not using the app (P=0.015). Our results confirmed that complete adherence to the app for at least 24 weeks was linked to alterations in cigarette smoking behavior among CAD patients. Trial Registration Number: IRCT20221016056204N1.

Cerebral autoregulation metrics correlate with some major morbidity and mortality outcomes after cardiac surgery

Background: Personalized arterial blood pressure management based on cerebral autoregulation has shown clinical relevance in cardiac surgery. Here we explore the associations between lower limit of cerebral autoregulation (LLA) metrics and postoperative outcomes in a heterogenous and high-acuity population of patients undergoing high-risk cardiovascular surgery. Methods: Autoregulation parameters were determined retrospectively in 686 patients undergoing cardiac surgery at UAB Hospital. Cerebral oximetry index (COx) and hemoglobin volume reactivity index (HVx) determine a patient’s unique LLA by examining the correlation between mean arterial pressure (MAP) and near-infrared spectroscopy signals. Logistic regression analyses explored associations of area under the time-pressure curve and duration below LLA with stroke, acute kidney injury, operative mortality, low cardiac output syndrome, and mechanical ventilation lasting more than 48 hours. Any incidence of these outcomes was considered as the primary outcome of interest: major morbidity or operative mortality (MMOM). Results: We explored the association of Area under the time-pressure curve for pressures less than patient-specific Lower Limits of Autoregulation (AUCABP&lt;LLA: and MMOM. Results are reported with odds ratio (OR) and 95% confidence intervals (CI). AUCABP&lt;LLA was not significantly associated with MMOM incidence (HVx: Odds Ratio 1.000, 95% CI 0.970-1.030, p=0.979; COx: OR 1.006, 95% CI 0.990-1.023, p=0.456). However, for components of MMOM, specifically operative mortality (HVx: OR 1.063, 95% CI 1.013-1.115, p=0.013; COx: OR 1.027, 95% CI 1.001-1.052, p=0.038) and low cardiac output syndrome (HVx: OR 1.036, 95% CI 1.004-1.068, p=0.025), there were statistically significant relationships with AUCABP&lt;LLA when controlling for logistic Euroscore and preoperative hemoglobin levels. Conclusions: Area under the time-pressure curve for pressures less than patient-specific LLA was not significantly associated with MMOM incidence. However, we found significant associations between components of MMOM, specifically operative mortality and low cardiac output syndrome, with an AUCABP&lt;LLA and time under LLA. These results suggest that LLA metrics might have utility in predicting specific postoperative outcomes, but their role in predicting overall MMOM may be limited in heterogenous and high-acuity patient populations. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

ASSOCIATION OF BLOOD PRESSURE WITH MORTALITY IN OLDEST OLD PEOPLE WITH FRAILTY IN CHINA: RESULTS FROM CHINESE LONGITUDINAL HEALTHY LONGEVITY SURVEY (CLHLS)

Objective: To determine the target blood pressure in old people (80+ years) with frailty. Design and method: In this community based, longitudinal prospective study, we enrolled 3,134 oldest old people with frailty. The exposure-response associations between blood pressure and all-cause mortality, cardiovascular disease (CVD) mortality, and non-CVD mortality were assessed by the penalized cubic splines fitted in Cox models. Results: During 5 years follow-up, 2,532 deaths were documented. An approximate L-shaped association between systolic blood pressure (SBP) and 5-year all-cause mortality was identified. Compared with 140 mmHg (inflection point), the risk of all-cause mortality significantly increased for SBP below 127 mmHg, which varied from HR of 1.050 (95% CI: 1.003-1.100) to 1.576 (95% CI: 1.128-2.203). After 140 mmHg, mortality risk gradually fell with increasing SBP, although not reaching statistical significance. Diastolic blood pressure (DBP) suggested a significant U-shaped association with 5-year all-cause mortality with 90 mmHg conferred the lowest risk. Before that, the risk of all-cause mortality rose with decreasing DBP, which varied from HR of 1.041 (95% CI: 1.001-1.082) to 1.304 (95% CI: 1.005-1.692). After 90 mmHg, although the observed differences were not statistically significant, mortality risk tended to rise with increasing DBP. Among the 2,037 participants with a confirmed cause of death, 346 died from CVDs and 1,691 died from non-CVDs. In comparison with 120 mmHg, SBP above 134 mm Hg exhibited a significantly elevated CVD mortality risk; when SBP below 121 mmHg, significantly increased non-CVD mortality risk could be found in comparison with SBP at 140 mmHg. As for DBP, it could not predict CVD mortality risk; there was an approximate U-shaped association between DBP and non-CVD mortality that DBP below 69 mmHg was associated with a higher risk with 85 mmHg as the reference. Stratified and sensitivity analyses showed robustness of main findings. Conclusions: In the oldest old people with frailty, in addition to all-cause mortality, blood pressure management should balance CVDs risk and non-CVD risk. Maintaining blood pressure at 120-140/80-100 mmHg can reduce all-cause mortality risk and meanwhile may prevent the adverse events due to excessively higher or lower blood pressure.

Inverse association of prepregnancy systolic blood pressure and live birth rate in normotensive women undergoing in vitro fertilization/intracytoplasmic sperm injection

To explore whether maternal baseline systolic blood pressure (SBP) and diastolic blood pressure (DBP) affect pregnancy outcomes particularly in normotensive women (SBP, 90-139 mm Hg; DBP, 60-89 mm Hg) and hypertensive women undergoing invitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI). Retrospective cohort study. Maximum care hospital for reproductive medicine. This study included 73,462 patients who underwent IVF/ICSI at the Reproductive and Genetic Hospital of CITIC-Xiangya between January 1, 2016, and November 30, 2020, selected on the basis of pre-established criteria. Analysis was limited to the first transfer cycle of the first stimulation cycle. Baseline SBP and DBP. The primary outcome focused on the live birth rate (LBR), with the secondary outcomes including clinical pregnancy rate, ectopic pregnancy rate, first-trimester miscarriage rate, second- or third-trimester fetal loss, and delivery/neonatal/maternal outcomes. Analytic methods included Poisson regression, linear regression, linear mixed-effect model, and restricted cubic spline analysis as appropriate. For normotensive women, a 10-mm Hg increase in SBP was associated with an adjusted relative risk of 0.988 (95% confidence interval, 0.981-0.995) for live birth likelihood. However, DBP was not significantly associated with LBR after adjustments. The secondary outcomes indicated that increases in SBP and DBP were associated with higher risks of first-trimester miscarriage, gestational diabetes mellitus, and gestational hypertension in the normotensive subset. Sensitivity analyses confirmed these associations between SBP/DBP and LBR, consistent with the main findings even under stricter guidelines and after adjusting for multiple confounders. Subgroup analyses showed variation in the impact of blood pressure on LBR across different demographics and conditions. Consistent with earlier studies on blood pressure and birth outcomes, we found a 10-mm Hg increase in SBP was associated with a 5.4% (adjusted relative risk per 10 mm Hg, 0.946; 95% confidence interval, 0.907-0.986) reduction in LBR in the hypertensive subgroup. Systolic blood pressure impacted LBR outcomes in normotensive women who underwent IVF/ICSI, which suggests the need for reconsidering blood pressure management guidelines for reproductive-age women, focusing on reproductive health in addition to cardiovascular risk.

Data‐efficient and risk‐based pressure sensor placement optimization for water systems

AbstractDeployment of remote metering infrastructure can help utilities improve pressure management and limit pipe break impacts. Since it is cost‐infeasible to install sensors to fully cover an entire system, a risk‐based approach where devices are deployed in areas of systemic vulnerabilities will maximize the benefit of these limited resources. Previous work on sensor allocations requires well‐calibrated hydraulic models that contain a full asset inventory. This high barrier of data requirement makes it difficult to apply existing methods. In this research, we present a more efficient methodology with lower data requirements. Proxies for system vulnerabilities are generated using historic break records, and GIS inventories are used to derive candidate installation points. The problem is presented as a generalized version of the well‐studied maximal coverage location problem, where locations are selected for optimal coverage of risky areas. The workflow is demonstrated on a small suburban utility in Pennsylvania, USA.