Volume Pulse Research Articles

Cardiopulmonary interactions-which monitoring tools to use?

Heart-lung interactions occur due to the mechanical influence of intrathoracic pressure and lung volume changes on cardiac and circulatory function. These interactions manifest as respiratory fluctuations in venous, pulmonary, and arterial pressures, potentially affecting stroke volume. In the context of functional hemodynamic monitoring, pulse or stroke volume variation (pulse pressure variation or stroke volume variability) are commonly employed to assess volume or preload responsiveness. However, correct interpretation of these parameters requires a comprehensive understanding of the physiological factors that determine pulse pressure and stroke volume. These factors include pleural pressure, venous return, pulmonary vessel function, lung mechanics, gas exchange, and specific cardiac factors. A comprehensive knowledge of heart-lung physiology is vital to avoid clinical misjudgments, particularly in cases of right ventricular (RV) failure or diastolic dysfunction. Therefore, when selecting monitoring devices or technologies, these factors must be considered. Invasive arterial pressure measurements of variations in breath-to-breath pressure swings are commonly used to monitor heart-lung interactions. Echocardiography or pulmonary artery catheters are valuable tools for differentiating preload responsiveness from right ventricular failure, while changes in diastolic function should be assessed alongside alterations in airway or pleural pressure, which can be approximated by esophageal pressure. In complex clinical scenarios like ARDS, combined forms of shock or right heart failure, additional information on gas exchange and pulmonary mechanics aids in the interpretation of heart-lung interactions. This review aims to describe monitoring techniques that provide clinicians with an integrative understanding of a patient's condition, enabling accurate assessment and patient care.

Non-Traumatic Coma in Children- A Review

Coma is defined as the unintentional failure of the patient to open their eyes spontaneously or in response to noise and inability to open for commands or localised painful stimuli with or without the ability to express comprehensible words or language response, whereas the Non traumatic coma is without any injury to the brain, and the Glasgow coma scale below 12. The Non traumatic coma causes due to the infections(tubercular meningitis, bacterial meningitis, encephalitis) and other metabolic conditions ,status epilepticus intracranial bleed, miscellaneous, hypoxic ischemic insults, Electrical shock, shunt dysfunction, Inborn error of metabolism. The monitoring parameters are Heart rate, Respiratory rate and pattern, Blood pressure, Temperature, coma severity using GCS, pupillary size, extra ocular movements, corneal reflex, posture, and motor pattern. The main symptoms are ataxia or weakness, isolated cranial nerve palsy, mild alteration of tone, poor pulse volume, apnea, abnormal pupillary size and reaction, dizziness, Headache, abnormal extra ocular movements absent corneal reflex. Management of non-traumatic coma patients at hospital includes Monitoring of Intracranial pressure, Maintenance of an adequate cerebral perfusion pressure, Management of persistent intracranial hypertension and Monitoring of Electroencephalographic Seizure activity. Infections are the most common cause for the non-traumatic coma in several cases. The pattern of infectious caused are CNS infections > metabolic toxic exposure > encephalitis > Intoxication > hypoxic ischemic insults > Intracranial haemorrhages>miscellaneous>unknown cases. 40% of children are prone to Non traumatic coma per 10000 general population per year.

Multi-Level Constrained Intra and Inter Subject Feature Representation for Facial Video Based BVP Signal Measurement.

Facial video-based blood volume pulse (BVP) signal measurement holds great potential for remote health monitoring, while existing methods have issues with convolutional kernel perceptual field constraints. This article proposes an end-to-end multi-level constrained spatiotemporal representation structure for facial video-based BVP signal measurement. First, an intra- and inter-subject feature representation is proposed to strengthen the BVP-related features generation at high, semantic, and shallow levels, respectively. Second, the global-local association is presented to enhance BVP signal period pattern learning, and the global temporal features are introduced into the local spatial convolution of each frame by adaptive kernel weights. Finally, the multi-dimensional fused features are mapped to one-dimensional BVP signals by the task-oriented signal estimator. The experimental results on the publicly available MMSE-HR dataset demonstrate that the proposed structure overperforms state-of-the-art methods (e.g., AutoHR) in BVP signal measurement, with a 20% and 40% reduction in mean absolute error and root mean squared error, respectively. The proposed structure would be a powerful tool for telemedical and non-contact heart health monitoring.

Mönckeberg's Medial Calcific Sclerosis Makes Traditional Arterial Doppler's Unreliable in High-Risk Patients with Diabetes.

To assess Mönckeberg's medial calcific sclerosis (MMCS) severity in patients with a diabetic foot infection. This was an analysis of 2 randomized clinical trials in which we evaluated the treatment of 233 patients admitted to the hospital for moderate and severe foot infections. Arterial calcification was defined as visible radiopaque arteries on foot and ankle radiographs, recorded as the most distal visible artery involved (toes, metatarsals, and ankle/hindfoot). Most subjects (57.1%, n = 133) had MMCS, with extension to toes in 79 (59.4%), to metatarsals in 32 (24.1%), and to ankle/hindfoot in 22 patients (16.5%). In 7 patients (5.2%) MMCS was solely seen in dorsalis pedis (DP) artery, in 13 patients (9.8%) in posterior tibialis (PT) artery, and in 113 patients (85.0%) MMCS was seen in both arteries. Only 29.2% (n = 68) of DP arteries and 34.8% (n = 81) of PT arteries were not compressible by Doppler. DP and PT arteries were not compressible more often in MMCS (DP 34.3% vs 20.4%, P = .02 and PT 43.1% vs 21.4%, P < .01), toe-brachial indices of ≥0.7 were significantly more common in people without MMCS (46.0% vs 67.4%, P < .01). In contrast, there were no differences in skin perfusion pressure measurements (>50 mmHg; 67.7% vs 68.0%, P = .96), waveforms (biphasic/triphasic 83.5% vs 77.0%, P = .22), and pulse volume recording (9.6 ± 3.3 vs 13.7 ± 36.0) between patients with and without MMCS. MMCS is common in patients with diabetic foot infections. MMCS is associated with noncompressible arterial Doppler studies and likely interferes with the accuracy of arterial Doppler studies.

VidBP: Detecting Blood Pressure from Facial Videos with Personalized Calibration.

Recent studies have found that blood volume pulse (BVP) in facial videos contains features highly correlated to blood pressure (BP). However, the mapping from BVP features to BP varies from person to person. To address this issue, VidBP has been proposed as a BP detector that can be calibrated based on an individual's data. VidBP is pre-trained on a large dataset to extract BP-related features from BVP. Then, BVP samples and BP labels of an individual are fed into the pre-trained VidBP to create a personal dictionary of BP-related features. When estimating the individual's BP, the current BP-related feature is compared to the features saved in the dictionary, and the BP labels of the similar features are considered as the BP estimate. The performance of VidBP was evaluated on 640 samples of 16 subjects, and it demonstrated significantly lower errors in BP estimation compared to state-of-the-art methods. The personalized calibration of VidBP is a significant advantage, enabling it to better capture the unique mapping from BVP features to BP for each individual.Clinical relevance This study reports a feasible method to estimate BP from facial videos, providing a convenient and cost-effective way for home BP monitoring.

Diffuse transmittance visible spectroscopy using smartphone flashlight for photoplethysmography and vital signs measurements

Photoplethysmography (PPG), with its wide range of applications, has become one of the most promising modalities for healthcare monitoring technology. In this work, we present a new PPG measurement technique based on diffuse transmittance spectroscopy (DTS) with the help of a smartphone built-in flashlight as an alternative broadband light source. The blood Volume Pulse (BVP) signal was extracted from recorded transmittance spectra at 620 nm. The results were compared with the ground truth and conventional contact finger PPG sensors. A very high correlation was found between the diffuse transmittance signal and the reference PPG signals (r = 0.997, p < 0.0001). The accuracy and root mean square error (RMSE) were 99.23% and 0.8 bpm, respectively. In addition, a Bland-Altman analysis showed a good agreement between both techniques, with a very small bias between mean paired differences of heart rate observations. A simple forward model for diffuse transmittance spectra for different levels of blood oxygen saturation is developed and supported by experimental measurements. It was also found that blood oxygen saturation (SpO2) can be estimated with the aid of DTS based smartphone flash by tracking the wavelength corresponding to the oxygenation level in the visible range between orange and red regions of the visible spectrum particularly in the range between 610 and 635 nm for 26 healthy subjects. 624 nm on average seems to be the wavelength that corresponds with the normal blood oxygenation level. These findings show the potential of DTS PPG to reliably extract cardiac frequency and estimate SpO2 with adequate accuracy. The results also demonstrate the capability of smartphone flash as a miniature visible light source for recording multispectral PPG signals and quantifying vital signs in the transmission mode at the fingertip with acceptable signal quality over a wide range of wavelengths from 550 nm to 650 nm.

Giant cell arteritis: An interesting case presentation.

Giant cell arteritis (GCA), otherwise known as temporal arteritis, is a form of large vessel vasculitis. Patients may present with a variety of symptoms but the most common include headaches, jaw claudication, fatigue, night sweats and visual disturbance. Diagnosis is made using a combination of temporal artery ultrasound, clinical findings and blood tests and the diagnostic gold standard of a temporal artery biopsy and is sometimes needed for histopathological confirmation. Syphilis is a sexually transmitted disease caused by the spirochaete Treponema pallidum, which can infect the central nervous system and cause neurosyphilis, which can mimic GCA.

Dysregulation of the autonomic nervous system in adult attention deficit hyperactivity disorder. A systematic review

ABSTRACT Background: Adult Attention Deficit Hyperactivity Disorder (aADHD) is characterised by inattention, hyperactivity, impulsivity, and emotional instability, all of which were linked to altered modulation of the autonomic nervous system. This and the clinical effectiveness of sympathomimetic medication raised the question if autonomic modulation is altered in aADHD patients. Methods: We systematically searched PubMed, Cochrane Library, and Web Of Science for publications investigating autonomic modulation in aADHD and controls during resting-state and/or under task conditions. Results: We reviewed 15 studies involving 846 participants (424 aADHD and 422 controls), including 4 studies on sympathetic tone at rest, 13 studies on sympathetic modulation during tasks, 3 studies on resting state parasympathetic modulation and 3 papers on task-related parasympathetic modulation. Studies comprised measurements of electrodermal activity, heart rate variability, blood pressure variability, blood volume pulse, pre-ejection period, and baroreflex sensitivity. 2 studies reported reduced sympathetic tone in aADHD; 7 papers described lower sympathetic reactivity to task demands in this cohort. One study linked aADHD to impaired vagal tone, while no indications of altered tasks-related parasympathetic reactivity in aADHD patients were reported. Conclusion: The reviewed data revealed impaired cardiovascular autonomic modulation in aADHD patients, predominantly in sympathetic modulation and during stress exposure.

Nanosecond volume discharge in the non-stationary high-speed profiled channel flow

The aim of the work is an experimental and numerical investigation of the interaction between the pulse volume discharge with a high-speed flow in the rectangular profiled channel (obstacle on the bottom wall). The special type of combined discharge—pulse volume discharge with preionization by an ultraviolet radiation from plasma sheets—is used. The flow around the obstacle influences the pulse discharge plasma distribution. The short-pulse initiation of a high power discharge leads to the effects observable in the time range up to millisecond. Ultrafast local heating of the medium with the formation of blast (shock) waves is carried out during the creation of a high nonequilibrium sub microsecond pulsed plasma. The duration of the shock-wave effect of the pulsed discharge is from 20 to 120 μs in supersonic and transonic flow. The spatially inhomogeneous distribution of energy input in a supersonic flow associates with the density lowest areas, which occur in a gas flow regime in a channel with an obstacle on the bottom. Discharge localization regions are sources of more intense wall surface local heating observed in the infrared range. A numerical calculation is carried out in order to match the calculated and experimental gas dynamical configurations.

Assessment of Fitness for Air travel in Patients with Pulmonary Diseases

During air travel, increasing hypoxia with altitude ascent is a potentially serious problem for patients with hypoxemic chronic airway obstruction (CAO). Travel by air is the most popular way of transport nowadays &amp; estimated that each year worldwide, more than 3 billion passengers travel by air &amp; 736 million in the United States alone. For most passengers, even those with respiratory disease, air travel is safe and comfortable. Some patients with COPD &amp;other Chronic Lung diseases may be at risk but, with screening, these patients can be identified and most of them can travel safely with supplemental oxygen. Some patients with chronic lung disease may have mild hypoxemia at sea level but during air travel in a hypobaric hypoxic environment, compensatory pulmonary mechanisms may be inadequate despite normal sea-level oxygen requirements. In addition, compensatory cardiovascular mechanisms may be less effective in some patients who are unable to increase cardiac output. Air travel also presents an increased risk of venous thromboembolism. It's estimated that, almost 1 medical emergency for every 600 flights. Respiratory symptoms accounted for 12% of all these in-air emergencies.&#x0D; Pulse Volume 12-14 2020-2022 p.16-21

Patient safety culture plays an essential role to ensure safe patient care and quality in healthcare services

Patient Safety is a global health priority. Every year, millions of patients suffer or die because of unsafe and poor- health care service. There are several factors which compromise patient safety and cause potential harm in health care settings. In developed countries, it is estimated that one in every 10 patients is harmed while receiving care in hospital. In developing countries, there is inadequate information on adverse event due to poor quality of health care service. Despite recent developments in Bangladesh, there is still great concern about the quality of care in healthcare sector. Evercare Hospital Dhaka is one of the leading private health care organizations in the country and committed towards patient safety from the very beginning. The purpose of this article is to discuss the importance of patient safety culture at healthcare service and how it is nurtured at Evercare hospital Dhaka by following the joint commission international standards.&#x0D; Pulse Volume 12-14 2020-2022 p.53-61

Papillary Tumor of Pineal Region: A Case Report

Pineal region tumors constitute about 0.4%-1% of intracranial tumors in adults. These tumors may arise from pineal gland itself or structures around it which are all termed as pineal region tumor. Papillary tumor of the pineal region is a non-parenchymal tumor of the pineal region. First described in 2003, it is an extremely rare tumor. We have presented a case of 27-year-old female patient presented as a pineal tumor. After successful excision, the tumor proved to be Papillary tumor of Pineal region (PTPR) both histomorphologically and immunohistochemical study.&#x0D; Pulse Volume 12-14 2020-2022 p.13-15

An interesting case of Posterior Layering in the Urinary bladder on Fluorine- 18 Fluorodeoxyglucose (F18-FDG) PET-CT study

Contrast PET/CT may show layering within the UB, and several examples of have been reported in the literature. But without using contrast this is rare. Our case demonstrates the interesting posterior layering of F18-FDG in urinary bladder in a 78 years old male without the use of contrast.&#x0D; Pulse Volume 12-14 2020-2022 p.32-33

Exosomes - A Potential Candidate to Combat Covid-19 and A Future Emerging Nanotechnology with Diverse Perspectives

Corona virus causes severe contagious acute respiratory syndrome known as coronavirus disease 2019 (COVID-19). Several initiatives have been taken to tackle so far. One of them, being therapy based biological nano particles “Exosomes”. Administration of exosomes loaded with immunomodulatory cargo in combination with antiviral drugs will be a promising approach. This study deals with the exosomal isolation techniques of the Bruton Tyrosine Kinase (BTK) protein from cells. It represents initial trials to establish a method to isolate exosomes from human B cells.&#x0D; Pulse Volume 12-14 2020-2022 p.22-25

Prevalence of Neisseria gonorrhoeae, Chlamydia trachomatis, Mycoplasma genitalium, and Trichomonas vaginalis among patients suspected of sexually transmitted infections in Evercare Hospital Dhaka during 2015 to 2022

Background Sexually Transmitted Infections (STIs) are often diagnosed by clinical symptoms and signs due to lack of sensitive laboratory methods. Most of the time pathogens are not identified and antibiotics are used empirically. The purpose of our study is to find out the STI pathogens detected by sensitive multiplex PCR done routinely in a tertiary care hospital.&#x0D; Materials and methods A total of 578 samples were tested from February 2015 to July 2022. Urine, prostatic secretion, urethral swab, high vaginal swab, semen, throat swabs were collected from symptomatic patients for the routine test. DNA was extracted and Neisseria gonorrhoeae, Chlamydia trachomatis, Mycoplasma genitalium, Trichomonas vaginalis were screened by using CE-IVD approved multiplex Real Time PCR kit.&#x0D; Result Out of 578 cases, 76 (13.15%) were positive for at least one pathogen and 5 were co-infections. Out of 76 positive cases, Chlamydia trachomatis was found 41 (53.9%), Neisseria gonorrhoeae was 13 (17.1%), Mycoplasma genitalium was 12 (15.8%), and Trichomonas vaginalis 5 (6.6%) and co-infections with Neisseria gonorrhoeae and Chlamydia trachomatis was 5 (6.6%). Positivity rate was remarkably higher in male (77.6%) than female (22.4%) and predominant age group was 19-40 years.&#x0D; Conclusion The predominant STIs pathogen found in our cohort is Chlamydia trachomatis followed by Neisseria gonorrhoeae. Multiplex PCR is a wide-ranging diagnostic method for the detection of multiple pathogens simultaneously which allows early and accurate diagnosis of STIs.&#x0D; Pulse Volume 12-14 2020-2022 p.34-39

Dominance of human Influenza H1N1pdm09 in flu like patients during early two months of 2020

Introduction:Influenza is a worldwide respiratory infectious disease which affect all age groups and associated with significant number of morbidity and mortality each year. The circulating subtypes varies countrywide yearly, and it helps policy maker to get preparedness for early effective management of influenza epidemics.&#x0D; Materials and methods Nasal swabs were collected from 463 patients in January and February 2020 presenting flu-like symptoms and Rapid Influenza Diagnostics Tests (RIDTs) were performed for influenza A &amp; B screening as a routine test. Then influenza A subtyping was done by RT-PCR followed by gel electrophoresis of 27 influenza positive samples.&#x0D; Result Among 463 cases, 106 (22.9%) were Influenza positive with huge (99.06%) dominance of Influenza A. Subtyping of randomly selected outpatient derived 27 Influenza A positive cases showed flourishing presence of seasonal Influenza A/H1N1pdm09 (21; 77.8%).&#x0D; Conclusion This small study warrants further elaborate investigation to know circulating influenza A subtyping in the country which may assist health care providers in making treatment decisions and hence, appropriate patient management.&#x0D; Pulse Volume 12-14 2020-2022 p.4-9

Infective Endocarditis Associated with Multisystem Inflammatory Syndrome in Children (MIS-C): Two Case Studies

Infective endocarditis (IE) is the infection of endocardial surface of the heart. IE is the rare disease with significant complications which require early diagnosis and proper treatment for reducing morbidity and mortality.IE with vegetation on pulmonary valve, leaflets are uncommon. However, we have diagnosed one case with infective endocarditis associated with Multisystem Inflammatory Syndrome in Children (MIS-C) which is related with COVID-19. MIS-C is commonly associated with coronary artery aneurysm (CAA), myocarditis and heart failure. Our patient had IE and was subsequently affected with MIS-C due to COVID. The child had vegetation on pulmonary valve with flail pulmonary valve-leaflet with grade II pulmonary regurgitation and MIS-C related CAA. The second child was previously diagnosed as infective endocarditis and was treated in other hospital for intravenous antibiotic for four weeks. However, in our hospital he was diagnosed clinically, by laboratory investigations and by echocardiography as MIS-C with large vegetation, which was surgically removed, and biopsy revealed mycobacterium tuberculosis as causative organism.&#x0D; Pulse Volume 12-14 2020-2022 p.26-31

Case series report of LINAC-based Stereotactic radiosurgery of Intracranial meningioma – an institutional experience

Stereotactic radiosurgery (SRS) has been widely used for the treatment of intracranial lesions. We have been doing SRS since March 2019. The unique ability of SRS to deliver higher focused dose to the smaller targets preferably in a single exposure in a convenient manner while sparing adjacent critical structures has made a more widely adopted treatment option. This case series is intended to show our institutional experience and procedural technique adapted for treating intracranial meningioma using SRS by Linear accelerators. We present five cases of intracranial meningioma. Four had Grade I meningioma and one patient with Grade III meningioma. One patient had radiological diagnosis only and treated with SRS. Two patients underwent gross total resection and SRS was prescribed on the event of recurrence. Rest two patients had recurrence/progression after subtotal resection and adjuvant radiation. The dose prescription ranged from 13 to 21Gy in one to three fractions which was determined by tumor volume, location, grade, proximity to critical structures, pre-existing neurologic impairment, previous treatment history, time to progression/relapse and the ideal balance of prescription dosage and expected problems. There were no acute side effects from any of the procedures. All five patients had improvement in clinical symptoms in the immediate post-SRS period. One patient who has two-year post-SRS revealed a significant regression in the size of the tumor. This case series summarizes the fact that SRS for intracranial meningioma is safe and effective treatment strategy when appropriate.&#x0D; Pulse Volume 12-14 2020-2022 p.40-52

Is Helminthiasis a Precipitating Factor for Frequently Relapsing Nephrotic Syndrome?

Nephrotic Syndrome (NS) is a common childhood illness. It is a disease of relapse and remission with major concern to manage the cases with relapse. Helminthiasis also a common problem in our subcontinent. So, it is very important to find out any relation with helminthiasis and relapse in children. In our study, 88 patients, clinically diagnosed as minimal change nephrotic syndrome, were studied to find out any relationship with helminthiasis and frequent relapse. 36 patients (40.9%) had no helminthic infection, 34 patients (38.6%) had helminthiasis and 18 patients (20.5%) had atopic disorders. 62 patients were successfully followed up for 6 months. Relapses occurred 47.8% (11/23) patients in non-helminthiasis group. 88.5% (23/26) in helminthiasis group and 84.6% (11/13) in atopic group, patients who completed follow up. Thirteen percent (3) patients in non-helminthiasis group, 50% (13) in helminthiasis group and 38.5% (5) in atopic group were found to be frequent relapser. The differences were statistically significant.&#x0D; Pulse Volume 12-14 2020-2022 p.10-12&#x0D;

A physiological signal database of children with different special needs for stress recognition

This study presents a new dataset AKTIVES for evaluating the methods for stress detection and game reaction using physiological signals. We collected data from 25 children with obstetric brachial plexus injury, dyslexia, and intellectual disabilities, and typically developed children during game therapy. A wristband was used to record physiological data (blood volume pulse (BVP), electrodermal activity (EDA), and skin temperature (ST)). Furthermore, the facial expressions of children were recorded. Three experts watched the children’s videos, and physiological data is labeled “Stress/No Stress” and “Reaction/No Reaction”, according to the videos. The technical validation supported high-quality signals and showed consistency between the experts.