Pressure Measurements Research Articles

Validation of oscillometric ratio and maximum gradient methods for non-invasive blood pressure measurement with intra-arterial blood pressure measurements as reference.

Most non-invasive blood pressure (BP) measurements are carried out using instruments which implement either the Ratio or the Maximum Gradient oscillometric method, mostly during cuff deflation, but more rarely during cuff inflation. Yet, there is little published literature on the relative advantages and accuracy of these two methods. In this study of 40 lightly sedated individuals aged 64.1 ± 9.6 years, we evaluate and compare the performance of the oscillometric ratio (K) and gradient (Grad) methods for the non-invasive estimation of mean pressure, SBP and DBP with reference to invasive intra-arterial values. There was no significant difference between intra-arterial estimates of mean pressure made via Korotkoff sounds (MP-OWE) or the gradient method (MP-Grad). However, 17.7% of MP-OWE and 15% of MP-Grad were in error by more than 10 mmHg. SBP-K and SBP-Grad underestimated SBP by 14 and 18 mmHg, whilst accurately estimating DBP with mean errors of 0.4 ± 5.0 and 1.7 ± 6.1 mmHg, respectively. Relative to the reference standard SBP-K, SBP-Grad and DBP-Grad were estimated with a mean error of -4.5 ± 6.6 and 1.4 ± 5.6 mmHg, respectively, noting that using the full range of recommended ratios introduces errors of 12 and 7 mmHg in SBP and DBP, respectively. We also show that it is possible to find ratios which minimize the root mean square error (RMSE) and the mean error for any particular individual cohort. We developed linear models for estimating SBP and SBP-K from a range of demographic and non-invasive OWE variables with resulting mean errors of 0.15 ± 5.6 and 0.3 ± 5.7 mmHg, acceptable according to the Universal standard.

Safety and prescribing recommendations for verapamil in newly diagnosed pediatric type 1 diabetes (T1D): The CLVer experience

ObjectivesTo report the safety and side effects associated with taking verapamil for beta-cell preservation in children with newly-diagnosed T1D. Research Design and MethodsEighty-eight participants aged 8.5 to 17.9 years weighing ≥ 30 kg were randomly assigned to verapamil (N = 47) or placebo (N = 41) within 31 days of T1D diagnosis and followed for 12 months from diagnosis, main CLVer study. Drug dosing was weight-based with incremental increases to full dosage. Side effect monitoring included serial measurements of pulse, blood pressure, liver enzymes, and electrocardiograms (ECGs). At study end, participants were enrolled in an observational extension study (CLVerEx), which is ongoing. No study drug is provided during the extension, but participants may use verapamil if prescribed by their diabetes care team. ResultsOverall rates of adverse events were low and comparable between verapamil and placebo groups. There was no difference in the frequency of liver function abnormalities. Three CLVer participants reduced or discontinued medication due to asymptomatic ECG changes. One CLVerEx participant (18 years old), treated with placebo during CLVer, who had not had a monitoring ECG, experienced complete AV block with a severe hypotensive episode 6 weeks after reaching his maximum verapamil dose following an inadvertent double dose on the day of the event. ConclusionsThe use of verapamil in youth newly-diagnosed with T1D appears generally safe and well tolerated with appropriate monitoring. We strongly recommend monitoring for potential side effects including an ECG at screening and an additional ECG once full dosage is reached.ClinicalTrials.gov number: NCT04233034.

Acute psychosocial stress modulates neural and behavioral substrates of cognitive control.

Acute psychosocial stress affects learning, memory, and attention, but the evidence for the influence of stress on the neural processes supporting cognitive control remains mixed. We investigated how acute psychosocial stress influences performance and neural processing during the Go/NoGo task-an established cognitive control task. The experimental group underwent the Trier Social Stress Test (TSST) acute stress induction, whereas the control group completed personality questionnaires. Then, participants completed a functional magnetic resonance imaging (fMRI) Go/NoGo task, with self-report, blood pressure and salivary cortisol measurements of induced stress taken intermittently throughout the experimental session. The TSST was successful in eliciting a stress response, as indicated by significant Stress > Control between-group differences in subjective stress ratings and systolic blood pressure. We did not identify significant differences in cortisol levels, however. The stress induction also impacted subsequent Go/NoGo task performance, with participants who underwent the TSST making fewer commission errors on trials requiring the most inhibitory control (NoGo Green) relative to the control group, suggesting increased vigilance. Univariate analysis of fMRI task-evoked brain activity revealed no differences between stress and control groups for any region. However, using multivariate pattern analysis, stress and control groups were reliably differentiated by activation patterns contrasting the most demanding NoGo trials (i.e., NoGo Green trials) versus baseline in the medial intraparietal area (mIPA, affiliated with the dorsal attention network) and subregions of the cerebellum (affiliated with the default mode network). These results align with prior reports linking the mIPA and the cerebellum to visuomotor coordination, a function central to cognitive control processes underlying goal-directed behavior. This suggests that stressor-induced hypervigilance may produce a facilitative effect on response inhibition which is represented neurally by the activation patterns of cognitive control regions.

Comparative analysis of intermittent and continuous energy restriction in obesity management

An alternative to continuous energy restriction in the medical nutrition treatment of obesity, which has come to the fore in recent times, is called intermittent fasting. The aim of this study is to compare the effects of intermittent energy restriction (IER) and continuous energy restriction (CER) practices on body composition and anthropometric measurements in overweight and first-degree obese individuals. The comparison study was conducted on 34 people aged 19-64 between April and September 2022. They had no health problems, and applied to a private institution providing nutrition consultancy. In the study, the participants were divided into two groups and were asked to maintain the IER or CER diet type for six weeks. When the participants in the two diet types were compared in terms of parameters of anthropometric measurements, body compositions, blood pressure measurements, and initial and final measurements of abdominal fat analysis, no statistically significant difference was found (pα, pβ>0.05). The mean weight loss of the participants in the IER and CER groups was 3.95±1.94 kg and 4.09±1.48 kg, respectively. The weight loss of the participants in the two diet groups was similar. The long-term efficacy and safety of time-restricted feeding in weight loss is still unclear. More comprehensive research is needed on this subject.

Super-Resolution Ultrasound Imaging for Monitoring the Therapeutic Efficacy of a Vascular Disrupting Agent in an Animal Model of Breast Cancer.

Evaluate the use of super-resolution ultrasound (SRUS) imaging for the early detection of tumor response to treatment using a vascular-disrupting agent (VDA). A population of 28 female nude athymic mice (Charles River Laboratories) were implanted with human breast cancer cells (MDA-MB-231, ATCC) in the mammary fat pad and allowed to grow. Ultrasound imaging was performed using a Vevo 3100 scanner (FUJIFILM VisualSonics Inc) equipped with the MX250 linear array transducer immediately before and after receiving bolus injections of a microbubble (MB) contrast agent (Definity, Lantheus Medical Imaging) via the tail vein. Following baseline ultrasound imaging, VDA drug (combretastatin A4 phosphate, CA4P, Sigma Aldrich) or control saline was injected via the placed catheter. After 4 or 24 hours, repeat ultrasound imaging along the same tumor cross-section occurred. Direct intratumoral pressure measurements were obtained using a calibrated sensor. All raw ultrasound data were saved for offline processing and SRUS image reconstruction using custom MATLAB software (MathWorks Inc). From a region encompassing the tumor space and the entire postprocessed ultrasound image sequence, time MB count (TMC) curves were generated in addition to traditional SRUS maps reflecting MB enumeration at each pixel location. Peak enhancement (PE) and wash-in rate (WIR) were extracted from these TMC curves. At termination, intratumoral microvessel density (MVD) was quantified using tomato lectin labeling of patent blood vessels. SRUS images exhibited a clear difference between control and treated tumors. While there was no difference in any group parameters at baseline (0 hour, P > .09), both SRUS-derived PE and WIR measurements in tumors treated with VDA exhibited significant decreases by 4 (P = .03 and P = .05, respectively) and 24 hours (P = .02 and P = .01, respectively), but not in control group tumors (P > .22). Similarly, SRUS derived microvascular maps were not different at baseline (P = .81), but measures of vessel density were lower in treated tumors at both 4 and 24 hours (P < .04). An inverse relationship between intratumoral pressure and both PE and WIR parameters were found in control tumors (R2 > .09, P < .03). SRUS imaging is a new modality for assessing tumor response to treatment using a VDA.

Estimation of the mean effective pressure of a spark ignition internal combustion engine using a neural network, considering the wall-wetting dynamics

The management and development of internal combustion engines stand as critical pursuits within the automotive and related industries. Utilizing cylinder pressure as feedback, engine controllers rely on intricate systems to regulate performance. However, due to the inherent complexity and nonlinearity of engines, direct measurement of cylinder pressure through pressure sensors is costly and computationally demanding. Consequently, the need for accurate and detailed engine models becomes paramount. Neural networks offer a promising avenue for simulating internal combustion engines, combining speed and precision. By treating the engine as an enigmatic entity, neural networks can construct detailed models. This study aims to employ two types of neural networks—multilayer perceptron and radial basis functions—to train and build a model of an internal combustion engine. These networks will simulate and estimate the engine's mean suitable pressure, allowing for a comparison of their effectiveness. Prior to implementing the neural network architecture, an engine model was constructed in MATLAB to gather necessary training data. This preliminary step ensured a robust foundation for subsequent network design and implementation. In summary, this research focuses on leveraging neural networks to model internal combustion engines, utilizing both multilayer perceptron and radial basis functions to simulate engine behavior and estimate mean suitable pressure.

Venous Congestion Assessed by Venous Excess Ultrasound (VExUS) and Acute Kidney Injury in Children with Right Ventricular Dysfunction.

Right ventricular dysfunction (RVD) is a complication following congenital cardiac surgery in children and can lead to systemic venous congestion, low cardiac output, and organ dysfunction. Venous congestion can be transmitted backwards and adversely affect encapsulated organs such as the kidneys. To investigate the association between systemic venous congestion, as estimated by Venous Excess Ultrasound (VExUS), and the occurrence of acute kidney injury (AKI) in children with RVD following congenital heart surgery. Secondary objectives included comparing changes in VExUS scores after initiating treatment for RVD and venous congestion. This was a prospective observational study in children with RVD. The VExUS study was performed on day 1, day 2, and day 3 and categorized as VExUS-1, VExUS-2, and VExUS-3. Among 43 patients with RVD and dilated inferior vena cava, 19/43 (44%), 10/43 (23%), and 12/43 (28%) were VExUS-2 and VExUS-3, respectively. There was an association between severe RVD and elevated pulmonary artery systolic pressures and a VExUS score >2. A significant association was observed between central venous pressure (CVP) measurements and VExUS. Among 31 patients with a high VExUS score >2, 18 (58%) had AKI. Additionally, improvement in CVP and fluid balance was associated with improving VExUS scores following targeted treatment for RVD. VExUS serves as a valuable bedside tool for diagnosing and grading venous congestion through ultrasound Doppler. An elevated VExUS score was associated with the occurrence of AKI, and among the components of VExUS, portal vein pulsatility may be useful as a predictor of AKI. Natraj R, Bhaskaran AK, Rola P, Haycock K, Siuba MTT, Ranjit S. Venous Congestion Assessed by Venous Excess Ultrasound (VExUS) and Acute Kidney Injury in Children with Right Ventricular Dysfunction. Indian J Crit Care Med 2024;28(5):447-452.

Unattended blood pressure measurement: is it really superior to traditional clinic readings?

Unattended blood pressure measurement: is it really superior to traditional clinic readings?

More shadows than lights in the blood pressure measurement method?

More shadows than lights in the blood pressure measurement method?

Oropharyngeal Dysphagia Phenotypes Across Huntington’s Disease Stages: Endoscopic Findings and Tongue Pressure Analysis

Background: Oropharyngeal dysphagia (OD) is a common symptom in Huntington’s disease (HD) and is associated with severe health and psychosocial consequences. Different OD phenotypes are defined on the basis of characteristic patterns at fiberoptic endoscopic evaluation of swallowing (FEES), and they may vary during disease progression. Objective: To describe OD phenotypes in different HD stages and to analyze their association with neurological data and tongue pressure measurements. Methods: Twenty-four patients with HD at different stages of disease progression underwent a FEES. Data on penetration/aspiration, pharyngeal residue, and OD phenotypes were gained. Neurological examination was performed with the Unified Huntington’s Disease Rating Scale (UHDRS). Patient Maximum tongue pressure (MTP) and tongue endurance were measured. Results: We confirmed that the occurrence of penetration/aspiration increased with disease duration and pharyngeal residue increased from 16.7% to 100% , respectively. The most common OD phenotypes were oropharyngeal dyspraxia (91.7% ), posterior oral incontinence (87.5% ), and delayed pharyngeal phase (87.5% ). These types of dysfunctions are already detectable in &gt;80% of patients in the early disease stages. In more advanced stages, we also observed propulsion deficit (66.7% ), resistive issue (54.2% ), and protective deficit (37.5% ). Propulsion deficit was associated with higher disease stage, greater motor dysfunction (UHDRS-I), and lower MTP and tongue endurance (p &lt; 0.05). Conclusions: OD in HD results from a combination of different swallowing phenotypes. Early assessment of swallowing and periodical follow-ups are necessary to monitor OD severity and phenotypes and to revise diet recommendations.

Diagnostics of acute compartment syndrome : Current gold standard and the state of science of noninvasive assessment methods

Acute compartment syndrome (ACS) is defined by a disorder of the microcirculation due to a persistent pathological pressure increase within amuscle compartment. The ischemia of the tissue leads to an initially reversible functional impairment and finally irreversible damage of the musculature, nerves and other structures. Based on the understanding of the pathophysiology, the current diagnostic concepts and treatment using the so-called dermatofasciotomy of the affected muscle compartments can be derived. In addition to the suspicion of a possible ACS based on the medical history of the patient, the findings of the clinical examination are decisive. This review article gives a summary of all the essential aspects of the diagnostics. In clinically uncertain cases and for monitoring, an objectification of the findings using instrument-based techniques is increasingly required. Nowadays, invasive needle pressure measurement is available; however, due to limited reliability, specificity and sensitivity, these measurements only represent an aid to decision guidance supporting or advising against the indications for dermatofasciotomy. The increasing demands on making a certain diagnosis and justification of a surgical intervention from a legal point of view, substantiate the numerous scientific efforts to develop noninvasive instrument-based diagnostics. These methods are based either on detection of increasing intracompartmental pressure or decreasing perfusion pressure and microcirculation. The various measurement principles are summarized in a lucid form.

The influence of crosswinds and leg positions on cycling aerodynamics

This work investigated the influence of crosswinds and leg positions on the aerodynamics of an articulated cycling mannequin on a track bicycle. Force, wake total pressure and wake velocity measurements were made in a low-speed sports wind tunnel of closed-circuit type. The freestream velocity and wheel speeds were kept at 15m/s\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$15\\, \\hbox {m/s}$$\\end{document}. The crank angle of the mannequin was varied across a pedal cycle. Yaw angles from 0∘\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$0^{\\circ }$$\\end{document} to 20∘\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$20^{\\circ }$$\\end{document} were examined. The experimental results reveal that the leg position significantly affects the aerodynamic performance of a cyclist. At high yaw angles, the aerodynamic drag on the cyclist showed noticeable deviations between most leg positions and their 180∘\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$180^{\\circ }$$\\end{document}-apart pairs. A wake analysis technique effectively captured the influence of leg positions on drag. The total pressure deficit contributes dominantly to the overall drag. The wake pressure contours demonstrate how leg-wheel interaction affects the total pressure distribution and drag under crosswinds. This study offers valuable insights into the flow behavior and drag generation around a cyclist with varying leg positions under crosswinds.

Resolution of Confusion Over Compartment Syndrome After Tibial Osteotomy With Continuous Pressure Measurements

Resolution of Confusion Over Compartment Syndrome After Tibial Osteotomy With Continuous Pressure Measurements

Predictive model for post-induction hypotension in patients undergoing transcatheter aortic valve implantation: a retrospective observational study

PurposePost-induction hypotension (PIH) is an independent risk factor for prolonged postoperative stay and hospital death. Patients undergoing transcatheter aortic valve implantation (TAVI) are prone to develop PIH. This study aimed to develop a predictive model for PIH in patients undergoing TAVI.MethodsThis single-center retrospective observational study included 163 patients who underwent TAVI. PIH was defined as at least one measurement of systolic arterial pressure <90 mmHg or at least one incident of norepinephrine infusion at a rate >6 µg/min from anesthetic induction until 20 min post-induction. Multivariate logistic regression analysis was performed to develop a predictive model for PIH in patients undergoing TAVI.ResultsIn total, 161 patients were analyzed. The prevalence of PIH was 57.8%. Multivariable logistic regression analysis showed that baseline mean arterial pressure ≥90 mmHg [adjusted odds ratio (aOR): 0.413, 95% confidence interval (95% CI): 0.193–0.887; p=0.023] and higher doses of fentanyl (per 1-µg/kg increase, aOR: 0.619, 95% CI: 0.418–0.915; p=0.016) and ketamine (per 1-mg/kg increase, aOR: 0.163, 95% CI: 0.062–0.430; p=0.002) for induction were significantly associated with lower risk of PIH. A higher dose of propofol (per 1-mg/kg increase, aOR: 3.240, 95% CI: 1.320–7.920; p=0.010) for induction was significantly associated with higher risk of PIH. The area under the curve (AUC) for this model was 0.802.ConclusionThe present study developed predictive models for PIH in patients who underwent TAVI. This model may be helpful for anesthesiologists in preventing PIH in patients undergoing TAVI.

Acute hemodynamic effects of the Marshall-Plan ablation on left and right atrial pressure: does 'respecting atrial physiology' prevent stiff left atria? A retrospective single- center analysis

Abstract Introduction Stiff left atrium (STILA)-syndrome is a relevant concern after extensive ablation in the left atrium (LA) e.g. in persistent atrial fibrillation (AF). STILA often causes disabling heart failure symptoms worse than the initial arrhythmia symptoms. Therefore preventing adverse ablation-induced hemodynamic effects is of utmost concern. Methods This single-center study retrospectively analyzed data from 89 consecutive patients who underwent biatrial ablation for AF following the Marshall-Plan between February 2022 and November 2023. The procedures included ablation of the CTI and PVI where necessary followed by ablation of a LA roof line and ablation of the lateral mitral isthmus after previously performed ethanol ablation of the vein of Marshall. This lesion set is considered to maintain physiological activation of the LA. This study evaluates acute hemodynamic changes following the Marshall-Plan. Invasive hemodynamic measurements of mean left and right atrial pressure, as well as A- and V-waves were performed in all patients before and after the ablation. We assessed the acute changes of atrial hemodynamics in these procedures. Continuous data are given as mean ± standard deviation, categorical data are expressed as number and percentages. Differences between groups were determined by Student’s t-test, chisquare-test, and Fisher’s exact test using SPSS software. A p-value of &amp;lt;0.05 was deemed significant. Results The patients' mean age was 70.1 ± 7.5 years and 39.0% were female. Mean BMI was 28.9 ± 5.2 kg/m². Procedures were performed under general anesthesia (with a PEEP of 5.5cmH2O (2-10 cmH2O)) and took 181 minutes on average. Left atrial mean pressure averaged at 15.7mmHg before the procedure. The overall average change of left atrial mean pressure was +1,8mmHg. The average change in left atrial A- and V-Wave amounted to -1.9mmHg and -0.9mmHg respectively. The pre-procedural average right atrial mean pressure was 12.1mmHg. Right atrial mean pressure inclined by +1.6mmHg. The average change in right atrial A- and V-Wave was +0.6mmHg and +1.1mmHg respectively. The i.v. administered volume averaged 1900 ± 285ml. 3.3% of patients showed an increase of mean LA-pressure &amp;gt;9mmHg. Those patients tended to be older (74.3years), were all male (100%) and had a higher BMI (31.5 kg/m²) as well as higher amount of i.v. administered volume (2333ml) and a longer procedure (213min). Discussion Complex and extensive biatrial ablation following the Marshall-Plan does not lead to acute significant increases in left or right atrial pressures. The administered i.v. volume might explain the slight increases observed. In our observation, the rate of significant increases in LA-pressure is low. This suggests that disrupting the (left) atrial activation pattern might play a role in the development of diastolic dysfunction and thereby STILA-syndrome. Respecting atrial physiology may be beneficial for preventing adverse hemodyamic changes after ablation.

LVSP and LBBP result in similar or improved LV synchrony and hemodynamics compared to biventricular pacing

Abstract Background The effect of left ventricular myocardial septal pacing (LVSP) and left bundle branch pacing (LBBP) on ventricular synchrony and LV hemodynamics is poorly understood in unselected cardiac resynchronization therapy (CRT) patients. Aim To investigate the impact of LBBP and LVSP on ultra-high-frequency ECG (UHF-ECG) ventricular synchrony and hemodynamics in CRT patients. Methods In consecutive CRT patients with LBBB, ventricular synchrony was assessed using UHF-ECG. LV hemodynamics was assessed using invasive systolic blood pressure measurement during multiple transitions between LBBP, LVSP, and biventricular pacing (BVP). LV synchrony was assessed by LV lateral wall delay (LVLWd) from the first to the last from V5-V8 activations. Hemodynamic effects were expressed as relative changes in systolic blood pressure. Results Thirty patients with an LVEF of 29 ± 6% and mean QRSd of 169 ± 24 ms were included. Twenty had non-ischemic cardiomyopathy. QRSd during BVP, LVSP, and LBBP was the same, but LBBP provided shorter LVLWd than BVP (-9 ms (-16; -4), p = 0.004); the difference between LVSP and BVP was not significant (-4 ms (-10;2), p = 0.2). LBBP was associated with higher systolic blood pressure than BVP (4% (2; 5) p &amp;lt; 0.001), while LVSP was not (1% (1; 2), p = 0.1. LV hemodynamic improvements during LBBP and LVSP vs. BVP were more pronounced in non-ischemic than ischemic patients. Conclusion The differences in ventricular synchrony between LBBP, LVSP, and BVP were demonstrated using UHF-ECG but not QRSd. LBBP, but not LVSP, was associated with better LV synchrony and hemodynamics than BVP.Local activation times in V1–V8Ventricular dyssynchrony and hemodynamic

3D-printed magnetic-based air pressure sensor for continuous respiration monitoring and breathing rehabilitation

The rapid development of point-of-care testing has made prompt diagnosis, monitoring and treatment possible for many patients suffering from chronic respiratory diseases. Currently, the biggest challenge is further optimizing testing devices to facilitate more functionalities with higher efficiency and performance, along with specificity toward patient needs. By understanding that patients with chronic respiratory diseases may have difficulty breathing within a normal range, a respiration sensor is developed focusing on sensitivities in the lower air pressure range. In contrast to the simpler airflow data, the sensor can provide respiratory air pressure as an output using a magnetic-based pressure sensor. This unconventional but highly reliable approach, combined with the rest of the simple 3D-printed design of the sensor, offers a wide range of tunability and functionalities. Due to the detachable components of the respiration sensor, the device can be easily transformed into other respiratory uses such as an inspiratory muscle training device or modified to cater for higher-ranged deep breathing. Therefore, not only does it reach very low air pressure measurement (0.1 cmH2O) for normal, tidal breathing, but the sensor can also be manipulated to detect high levels of air pressure (up to 35 cmH2O for exhalation and 45 cmH2O for inhalation). With its excellent sensitivities (0.0456 mV/cmH2O for inhalation, -0.0940 mV/cmH2O for exhalation), impressive distinction between inhalation and exhalation, and fully reproducible and convenient design, we believe that this respiration sensor will pave the way for developing multimodal and multifunctional respiration sensors within the biomedical field.

Comparative Analysis of Pharmacological and Non-Pharmacological Interventions in Hypertensive Patients at Cumilla Medical College Hospital

Background: Hypertension is a prevalent cardiovascular condition requiring effective management to reduce associated morbidity and mortality. Both pharmacological and non-pharmacological interventions play crucial roles in its treatment. This study aims to compare the effectiveness of these interventions in hypertensive patients at Cumilla Medical College Hospital, Bangladesh. Objective: To conduct a comparative analysis of pharmacological and non-pharmacological interventions in hypertension management. Method: A prospective study was conducted using data from the Department of Medicine at Cumilla Medical College Hospital, Bangladesh, from January 2023 to December 2023. A total of 184 patients were included in the study. Data on pharmacological and non-pharmacological interventions were collected, and blood pressure measurements were recorded. Result: Among the 184 patients, 65% received pharmacological interventions, while 35% received non-pharmacological interventions. Of those receiving pharmacological interventions, 82% achieved blood pressure control, compared to 73% in the non-pharmacological group. The mean reduction in systolic blood pressure was 20 mmHg in the pharmacological group and 15 mmHg in the non-pharmacological group. Regarding lifestyle modifications, 45% of patients in the non-pharmacological group reported improved dietary habits, and 55% reported increased physical activity. Conclusion: Both pharmacological and non-pharmacological interventions effectively manage hypertension, with pharmacological interventions showing slightly higher blood pressure control rates. However, non-pharmacological interventions are valuable for improving lifestyle factors. A combination of both approaches may be optimal for hypertension management.

A Study of the Relationship Between the Severity of Posterior Capsular Opacification Detected by Objective Detection Techniques and Visual Acuity.

To explore the severity of posterior capsule opacification (PCO) using objective detection techniques and its relationship with visual acuity. The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China. Prospective cohort study. All patients underwent slit-lamp examination, intraocular pressure measurement (IOP), best-corrected visual acuity (BCVA) before neodymium: yttrium aluminium garnet (Nd:YAG) laser capsulotomy, followed by examination after fully dilated, including IOLMaster 700, optical coherence tomography (OCT), Sirius anterior segment analysis system (Sirius), color fundus photography (CFP). Conducting BCVA and IOP post-treatment again. Recording the thickness and density of posterior capsule, color fundus photography quality (CFPQ) and OCT Signal Strength (OCTSS). Analysis using Spearman correlation analysis, heatmaps, and ROC curves. A total of 83 eyes in 78 patients were included in this study. Spearman correlation analysis revealed correlations between pre-treatment BCVA and IOLMaster 700 PCO thickness (MT), IOLMaster 700 cumulative effect (MCE), Sirius PCO thickness (ST), Sirius maximum density (SMD), Sirius cumulative effect (SCE), OCTSS, and CFPQ (correlation coefficients were 0.500, 0.484, 0.465, -0.256, 0.317, -0.442, -0.412, all P＜0.05). The improvement of Vision Acuity (ImpVA) showed correlations with MT, MCE, ST, SCE, OCTSS, and CFPQ (correlation coefficients were -0.452, -0.471, -0.346, -0.278, 0.320, 0.381, all P＜0.05). For ImpVA, the predictive ability of IOLMaster 700 was superior to Sirius, and the joint model was significantly better than single factors. Posterior capsule thickness and cumulative effect were reliable indicators for evaluating PCO. Compared to Sirius, IOLMaster 700 demonstrates superior predictive ability and higher correlation.

#2570 Non-invasive blood pressure monitoring in dialysis patients using pulse wave velocity

Abstract Background and Aims Dialysis patients are at high risk of circulatory dysregulation and hypotension during treatment. Intradialytic hypotension (IDH) is a potentially life-threatening complication. The main causes are high ultrafiltration volumes and high ultrafiltration rates when patients tend to gain a lot of weight between dialysis treatments. A lack of patient compliance with regard to drinking volumes and a lack of residual diuresis are risk factors for this. Close circulatory monitoring and therapy settings to avoid absolute or relatively high UF rates to prevent IDH are frequently used. These are primarily the frequent non-invasive measurement of blood pressure using cuffs, the measurement of relative blood volume and the adjustment of ultrafiltration rates to these values. Prophylactically, the dialysis time can be extended, ultrafiltration profiles or ultrafiltration breaks can be planned, the dialysate temperature can be lowered and the composition of the dialysate can be adjusted. Despite all attempts, however, the incidence of IDH in everyday clinical practice is too high. The non-invasive measurements with cuffs are not carried out frequently enough, the measurement of the relative blood volume only covers a partial range, sudden changes in vascular tension or cardiac output are not recorded. Method The pulse wave velocity (PWV) is a well-known parameter for describing the propagation of the pressure wave after ejection of the heart beat volume in the arteries. The PWV is dependent on blood pressure, vessel wall tension and cardiac output. Changes in blood pressure can therefore be recognised by measuring the PWV. With the help of a measuring device (PESAS) for the ECG signal and peripheral pulse plethysmography, PWV can be measured non-invasively, continuously, for every heartbeat and, above all, hardly noticed by the patient. The PESAS allows the time-synchronised measurement of ECG and peripheral plethysmography curves and thus the determination of PWV. It is an experimental device. We would like to present a study showing the use of a measuring device (PESAS) in 15 prevalent dialysis patients for the detection of IDH. All study participants were examined during 3 dialysis treatments. Results The measurement of PWV in chronic dialysis patients during treatment is technically feasible. The measurement is tolerated by the patients. Changes in PWV could be detected in the patients during the course of dialysis; these were also dependent on the ultrafiltration rates. Individual patient reactions to volume withdrawal varied, with both increases and decreases in PWV being demonstrated. An acute change in PWV was usually associated with a drop in blood pressure. Continuous measurement allowed IDH events to be detected earlier than intermittent blood pressure measurement with cuffs. Sudden drops in blood pressure could be detected better and earlier with the PESAS system than by measuring the relative blood volume. Conclusion The PESAS system is suitable for monitoring dialysis patients to prevent IDH. Further adjustments and optimisation of the evaluation algorithms are necessary.