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1.
Am J Bioeth ; 24(6): 27-33, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38829586

ABSTRACT

The introduction of normothermic regional perfusion (NRP) in controlled donation after circulatory determination of death (cDCDD) protocols is by some regarded as controversial and ethically troublesome. One of the main concerns that opponents have about introducing NRP in cDCDD protocols is that reestablishing circulation will negate the determination of death by circulatory criteria, potentially resuscitating the donor. In this article, I argue that this is not the case. If we take a closer look at the concept of death underlying the circulatory criterion for determination of death, we find that the purpose of the criterion is to show whether the organism as a whole has died. I argue that this purpose is fulfilled by the circulatory criterion in cDCDD protocols, and that applying NRP does not negate the determination of death or resuscitate the donor.


Subject(s)
Death , Tissue and Organ Procurement , Humans , Tissue and Organ Procurement/ethics , Perfusion , Tissue Donors/ethics , Resuscitation/ethics , Blood Circulation
3.
Zhongguo Zhong Yao Za Zhi ; 49(7): 1974-1980, 2024 Apr.
Article in Chinese | MEDLINE | ID: mdl-38812210

ABSTRACT

Hypertension is the most common chronic disease in clinics and has become the most common risk factor for cardiovascular diseases. Because of its high incidence rate, disability rate, and mortality, it has attracted worldwide attention. Despite continuous progress in modern medicine in the treatment of hypertension with new antihypertensive drugs such as Zilebesiran, a nucleic acid drug that acts on microRNA, direct renin inhibitors, and renal sympathetic blockade, the control rate is still not ideal. How to effectively prevent and control hypertension has become one of the urgent clinical challenges to be solved. Traditional Chinese medicine(TCM) has a long record of treating hypertension and has accumulated rich experience, including theoretical understanding, effective single medicine, compound medicine, traditional Chinese patent medicines, and classic famous prescriptions. In TCM, hypertension belongs to the categories of diseases such as dizziness and headache. Previous literature and clinical studies have found that hypertension has key pathogenesis such as fire syndrome, fluid syndrome, deficiency syndrome, and blood stasis syndrome. Among them, the hyperactivity of liver Yang is closely related to blood pressure fluctuations, blood pressure variability, inflammation, and sympathetic activity stimulation. Internal obstruction by blood stasis is closely related to the damage of target organs such as the heart, brain, and kidneys in hypertension. Therefore, the two key pathogenesis of liver yang hyperactivity and internal obstruction by blood stasis run through the entire process of hypertension. Previous studies have found that the effective empirical formula Tianxiong Granules, based on the principles of suppressing Yang and promoting blood circulation, originated from the classic formula Xiongqiong Tianma Pills in Yu Yao Yuan Fang. It is composed of Gastrodiae Rhizoma, Chuanxiong Rhizoma, Puerariae Lobatae Radix, Achyranthis Bidentatae Radix, and Cyathulae Radix and has significant therapeutic effects in the treatment of hypertension. The clinical indications include headache, dizziness, bloating, strong neck, and weak waist and legs. At the same time, it may be accompanied by poor speech, thirst, normal or loose stools, soreness in the waist and legs, lower limb pain, muscle and pulse spasm, menstrual and abdominal pain, dark red tongue, strong pulse strings, or straight and long pulse strings that pass through the mouth of an inch. In the combination rule, it can be used according to the different pathogenesis stages of hypertension patients. In the fire syndrome stage, it is often combined with Tianma Gouteng Decoction and Chaihu Jia Longgu Muli Decoction. In the fluid syndrome stage, it is often combined with Banxia Baizhu Tianma Decoction. In the deficiency syndrome stage, it is often combined with Liuwei Dihuang Pills and Shenqi Pills. In terms of dosage, it is important to focus on the main symptoms and adjust the dosage of key drugs based on blood pressure values. Some drugs can be used in sufficient quantities. By analyzing the compatibility of Tianxiong Granules, clinical application indications, combined formula experience, and dosage application experience, we provide effective treatment methods and more options for TCM to treat hypertension with Yang hyperactivity and blood stasis syndrome.


Subject(s)
Drugs, Chinese Herbal , Hypertension , Humans , Hypertension/drug therapy , Hypertension/physiopathology , Drugs, Chinese Herbal/administration & dosage , Drugs, Chinese Herbal/therapeutic use , Blood Circulation/drug effects , Blood Pressure/drug effects , Medicine, Chinese Traditional , Antihypertensive Agents/pharmacology
4.
Complement Ther Med ; 82: 103039, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38616000

ABSTRACT

BACKGROUND: Traditional Chinese medicine injection for Activating Blood Circulation (TCMi-ABC), which exhibits comparable anticoagulant and antiplatelet effects, is commonly used as an adjuvant treatment for acute myocardial infarction (AMI) in China. OBJECTIVE: The aim of this study was to conduct a meta-analysis to assess the efficacy and safety of TCMi-ABC in combination with conventional western medicine in reducing mortality associated with AMI. METHODS: We conducted a comprehensive search of PubMed, Cochrane Library, EMBASE, Web of Science, CBM, WanFang Data, and CNKI databases. Randomized controlled trials (RCTs) investigating the use of TCMi-ABC (including Danhong injection, sodium tanshinone IIA sulfonate injection, salvia miltiorrhiza ligupyrazine injection, and puerarin injection) for the treatment of AMI were included. The search included studies published from the inception of the databases up to December 2022. Two authors independently screened RCTs, extracted data, and assessed the risk of bias. Meta-analysis was performed using RevMan 5.3 and Stata 17.0. The quality of evidence was evaluated using the GRADE approach. RESULTS: A total of 52 RCTs involving 5363 patients were included in the analysis, none of which described independent testing of the purity or potency of the TCMi-ABC product used. 19/52 reported random sequence generation. All RCTs lack adequate description of allocation concealment. 51/52 failed to assess blinding. The meta-analysis results demonstrated that the combined application of TCMi-ABC, compared with conventional western medicine treatment alone, significantly reduced in-hospital mortality in AMI patients [RR= 0.41, 95% CI (0.29, 0.59), P < 0.05], decreased the incidence of malignant arrhythmia [RR= 0.40, 95% CI (0.26, 0.61), P < 0.05], and increased left ventricular ejection fraction (LVEF) [MD= 5.53, 95% CI (3.81, 7.26), P < 0.05]. There was no significant difference in the incidence of adverse events between the two groups (P > 0.05). The GRADE evidence quality classification indicated that the evidence for in-hospital mortality, malignant arrhythmia, and adverse events was of moderate quality, while the evidence for LVEF was of low quality. CONCLUSION: TCMi-ABC demonstrates additional clinical value in reducing mortality and the risk of malignant arrhythmia in patients with AMI. However, further validation of these findings is warranted through high-quality clinical trials due to methodological weaknesses in randomization, blinding, allocation concealment, and insufficient assessing for the purity/potency of herbs and the gram amount of active constituents. SYSTEMATIC REVIEW REGISTRATION: [INPLASY], identifier [INPLASY202170082].


Subject(s)
Anticoagulants , Drugs, Chinese Herbal , Myocardial Infarction , Platelet Aggregation Inhibitors , Randomized Controlled Trials as Topic , Humans , Anticoagulants/therapeutic use , Blood Circulation/drug effects , Drugs, Chinese Herbal/therapeutic use , Injections , Medicine, Chinese Traditional/methods , Myocardial Infarction/drug therapy , Platelet Aggregation Inhibitors/therapeutic use
5.
J Exp Zool A Ecol Integr Physiol ; 341(7): 766-782, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38651594

ABSTRACT

The brachiopods are sessile invertebrates with an unusual blood system, which consists of a long-branched dorsal vessel. It is still unknown how blood circulates in this system. In the present study, for the first time we propose the circulation of blood in brachiopod Hemithiris psittacea based on morphological and experimental data. The main heart is located on the dorsal side of the stomach and divides the dorsal vessel into anterior and posterior parts. The anterior part enters the lophophore, where it gives off blind branches to each tentacle. The posterior part passes by the funnels of the nephridia and forms a blindly closed network in the gonads. We suggest that the circulation of blood includes three successive stages. During the first phase of systole of the main heart, blood flows through the anterior dorsal vessel. During the second phase of systole, blood flows through the posterior dorsal vessel. During diastole, blood flows from the anterior and posterior vessels and fills the main heart. The origin of a peculiar blood system in brachiopods can be explained by reduction of the ventral vessel, which is probably correlates with the reduction of the ventral side of the brachiopod ancestor's body. Another peculiarity of brachiopod blood system is the presence of an ampullar heart, which functions as a blood depot and allows blood to move in the vessels in two directions in an oscillatory mode. The brachiopod blood system contains vessels lacking true endothelium and can be classified as an "incompletely closed" type.


Subject(s)
Invertebrates , Animals , Invertebrates/anatomy & histology , Blood Vessels , Blood Circulation
7.
Science ; 383(6683): eade8064, 2024 Feb 09.
Article in English | MEDLINE | ID: mdl-38330107

ABSTRACT

Penile erection is mediated by the corpora cavernosa, a trabecular-like vascular bed that enlarges upon vasodilation, but its regulation is not completely understood. Here, we show that perivascular fibroblasts in the corpora cavernosa support vasodilation by reducing norepinephrine availability. The effect on penile blood flow depends on the number of fibroblasts, which is regulated by erectile activity. Erection dynamically alters the positional arrangement of fibroblasts, temporarily down-regulating Notch signaling. Inhibition of Notch increases fibroblast numbers and consequently raises penile blood flow. Continuous Notch activation lowers fibroblast numbers and reduces penile blood perfusion. Recurrent erections stimulate fibroblast proliferation and limit vasoconstriction, whereas aging reduces the number of fibroblasts and lowers penile blood flow. Our findings reveal adaptive, erectile activity-dependent modulation of penile blood flow by fibroblasts.


Subject(s)
Excitatory Amino Acid Transporter 1 , Fibroblasts , Penile Erection , Penis , Receptors, Notch , Animals , Male , Mice , Blood Circulation , Excitatory Amino Acid Transporter 1/metabolism , Fibroblasts/metabolism , Fibroblasts/physiology , Mice, Inbred BALB C , Mice, Inbred C57BL , Mice, Transgenic , Penile Erection/physiology , Penis/blood supply , Penis/physiology , Receptors, Notch/metabolism , Signal Transduction , Vasoconstriction , Vasodilation
9.
Rev. esp. anestesiol. reanim ; 71(1): 48-53, Ene. 2024. ilus
Article in Spanish | IBECS | ID: ibc-230174

ABSTRACT

La cirugía cardíaca por toracoscopia videoasistida (VATS) requiere ventilación unipulmonar (VUP) y monitorización con ecografía transesofágica (ETE). Utilizando Doppler color y espectral es posible estudiar el patrón de flujo sanguíneo en los vasos pulmonares dentro del pulmón atelectasiado. El objetivo de este reporte de casos es evidenciar la habilidad de la ETE para detectar el flujo sanguíneo dentro del pulmón atelectásico, así como también valorar la resistencia vascular pulmonar (RVP) y poscarga del ventrículo derecho, utilizando esta misma herramienta. Hallazgos: Tres adultos anestesiados y ventilados mecánicamente programados para cirugía cardíaca por VATS fueron escaneados con ETE cardiopulmonar. Una vez que se realizó la VUP quedando el pulmón derecho sin ventilar, la sonda se giró desde el corazón para lograr un escaneo pulmonar 2D y con Doppler color para detectar el flujo de sangre dentro del parénquima pulmonar consolidado. Se pudo identificar el patrón de flujo correspondiente a las ramas de la arteria intrapulmonar. La RVP fue registrada aplicando Doppler pulsado cardíaco, basal luego de la inducción de anestesia general, a los 20min de la VUP y al finalizar la VUP, luego de realizar una maniobra de reclutamiento alveolar (MRA) que condujo a la resolución completa de la consolidación mencionada. Conclusiones: La ETE cardiopulmonar es una herramienta de imagen semiinvasiva que permite no solo el diagnóstico y estudio de atelectasias inducidas por VUP, sino también el análisis del shunt dentro de esta consolidación y sus posibles consecuencias en la RVP.(AU)


Video-assisted thoracoscopy (VATS) cardiac surgery requires one-lung ventilation (OLV) and transoesophageal ultrasound (TOE) monitoring. Colour and spectral Doppler make it possible to study the pattern of blood flow in the pulmonary vessels within the atelectatic lung. In this case report we describe how TOE can be used to detect blood flow within the atelectatic lung and to assess pulmonary vascular resistance (PVR) and right ventricular afterload. Findings: Three anaesthetised, mechanically ventilated adults scheduled for VATS cardiac surgery were monitored using TOE. After left OLV, the transducer was rotated away from the heart to obtain 2D colour Doppler images of blood flow within the consolidated lung parenchyma. We were able to identify the flow pattern of the intrapulmonary branches of the pulmonary artery. PVR was recorded using pulsed cardiac Doppler at baseline, after induction of general anaesthesia, 20min after OLV and at the end of OLV, and after performing an alveolar recruitment manoeuvre (ARM) that led to complete resolution of the aforementioned consolidation. Conclusions: TOE is a semi-invasive imaging tool that can be used to diagnose and study PVR-induced atelectasis and to analyse the resulting pulmonary shunt and its possible effect on PVR.(AU)


Subject(s)
Humans , Male , Female , Middle Aged , Echocardiography, Transesophageal , Heart Ventricles , Pulmonary Atelectasis , Blood Circulation , Ultrasonography, Doppler, Color
11.
IEEE Trans Biomed Eng ; 71(2): 563-573, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37643096

ABSTRACT

OBJECTIVE: Reynolds Averaged Navier Stokes (RANS) models are often used as the basis for modeling blood damage in turbulent flows. To predict blood damage by turbulence stresses that are not resolved in RANS, a stress formulation that represents the corresponding scales is required. Here, we compare two commonly employed stress formulations: a scalar stress representation that uses Reynolds stresses as a surrogate for unresolved fluid stresses, and an effective stress formulation based on energy dissipation. METHODS: We conducted unsteady RANS simulations of the CentriMag blood pump with three different closure models and a Large Eddy Simulation (LES) for reference. We implemented both stress representations in all models and compared the resulting total stress distributions in Eulerian and Lagrangian frameworks. RESULTS: The Reynolds-stress-based approach overestimated the contribution of unresolved stresses in RANS, with differences between closure models of up to several orders of magnitude. With the dissipation-based approach, the total stresses predicted with RANS deviated by about 50% from the LES reference, which was more accurate than only considering resolved stresses. CONCLUSION: The Reynolds-stress-based formulation proved unreliable for estimating scalar stresses in our RANS simulations, while the dissipation-based approach provided an accuracy improvement over simply neglecting unresolved stresses. SIGNIFICANCE: Our results suggest that dissipation-based inclusion of unresolved stresses should be the preferred choice for blood damage modeling in RANS.


Subject(s)
Blood Circulation , Computer Simulation
12.
PLoS One ; 18(10): e0289652, 2023.
Article in English | MEDLINE | ID: mdl-37856567

ABSTRACT

The heart is widely acknowledged as the unique driver of blood circulation. Recently, we discovered a flow-driving mechanism that can operate without imposed pressure, using infrared (IR) energy to propel flow. We considered the possibility that, by exploiting this mechanism, blood vessels, themselves, could propel flow. We verified the existence of this driving mechanism by using a three-day-old chick-embryo model. When the heart was stopped, blood continued to flow for approximately 50 minutes, albeit at a lower velocity. When IR was introduced, the postmortem flow increased from ~41.1 ± 25.6 µm/s to ~153.0 ± 59.5 µm/s (n = 6). When IR energy was diminished under otherwise physiological conditions, blood failed to flow. Hence, this IR-dependent, vessel-based flow-driving mechanism may indeed operate in the circulatory system, complementing the action of the heart.


Subject(s)
Cardiovascular System , Heart , Heart/physiology , Hemodynamics , Blood Flow Velocity/physiology , Blood Circulation , Blood Pressure
14.
Zhongguo Zhong Yao Za Zhi ; 48(7): 1908-1915, 2023 Apr.
Article in Chinese | MEDLINE | ID: mdl-37282967

ABSTRACT

This study aimed to analyze the biological foundation and biomarkers of stable coronary heart disease(CHD) with phlegm and blood stasis(PBS) syndrome based on RNA-seq and network pharmacology. Peripheral blood nucleated cells from five CHD patients with PBS syndrome, five CHD patients with non-PBS syndrome, and five healthy adults were collected for RNA-seq. The specific targets of CHD with PBS syndrome were determined by differential gene expression analysis and Venn diagram analysis. The active ingredients of Danlou Tablets were screened out from the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform, and the "component-target" prediction was completed through PubChem and SwissTargetPrediction. The "drug-ingredient-target-signaling pathway" network of Danlou Tablets against CHD with PBS syndrome was optimized by Cytoscape software. After the target biomarkers were identified, 90 participants were enrolled for diagnostic tests, and 30 CHD patients with PBS syndrome were included in before-and-after experiment to determine the therapeutic effect of Danlou Tablets on those targets. As revealed by RNA-seq and Venn diagram analysis, 200 specific genes were identified for CHD with PBS syndrome. A total of 1 118 potential therapeutic targets of Danlou Tablets were predicted through network pharmacology. Through integrated analysis of the two gene sets, 13 key targets of Danlou Tablets in the treatment of CHD with PBS syndrome were screened out, including CSF1, AKR1C2, PDGFRB, ARG1, CNR2, ALOX15B, ALDH1A1, CTSL, PLA2G7, LAP3, AKR1C3, IGFBP3, and CA1. They were presumably the biomarkers of CHD with PBS syndrome. The ELISA test further showed that CSF1 was significantly up-regulated in the peripheral blood of CHD patients with PBS syndrome, and was significantly down-regulated after Danlou Tablets intervention. CSF1 may be a biomarker for CHD with PBS syndrome, and it is positively correlated with the severity of the disease. The diagnostic cut-off of CSF1 for CHD with PBS syndrome was 286 pg·mL~(-1).


Subject(s)
Biomarkers , Coronary Disease , Drugs, Chinese Herbal , Medicine, Chinese Traditional , Mucus , Adult , Humans , Biomarkers/analysis , Coronary Disease/complications , Coronary Disease/diagnosis , Coronary Disease/drug therapy , Coronary Disease/genetics , Drugs, Chinese Herbal/pharmacology , Drugs, Chinese Herbal/therapeutic use , Molecular Docking Simulation , Network Pharmacology , RNA-Seq , Syndrome , Mucus/metabolism , Sputum/metabolism , Blood Circulation , Leukocytes, Mononuclear/pathology , Macrophage Colony-Stimulating Factor/genetics , Macrophage Colony-Stimulating Factor/metabolism , Gene Expression/drug effects , Gene Expression Profiling
15.
JACC Cardiovasc Imaging ; 16(9): 1149-1159, 2023 09.
Article in English | MEDLINE | ID: mdl-37204381

ABSTRACT

BACKGROUND: Up to 25% of embolic strokes occur in individuals without atrial fibrillation (AF) or other identifiable mechanisms. OBJECTIVES: This study aims to assess whether left atrial (LA) blood flow characteristics are associated with embolic brain infarcts, independently of AF. METHODS: The authors recruited 134 patients: 44 with a history of ischemic stroke and 90 with no history of stroke but CHA2DS2VASc score ≥1. Cardiac magnetic resonance (CMR) evaluated cardiac function and LA 4-dimensional flow parameters, including velocity and vorticity (a measure of rotational flow), and brain magnetic resonance imaging (MRI) was performed to detect large noncortical or cortical infarcts (LNCCIs) (likely embolic), or nonembolic lacunar infarcts. RESULTS: Patients (41% female; age 70 ± 9 years) had moderate stroke risk (median CHA2DS2VASc = 3, Q1-Q3: 2-4). Sixty-eight (51%) had diagnosed AF, of whom 58 (43%) were in AF during CMR. Thirty-nine (29%) had ≥1 LNCCI, 20 (15%) had ≥1 lacunar infarct without LNCCI, and 75 (56%) had no infarct. Lower LA vorticity was significantly associated with prevalent LNCCIs after adjustment for AF during CMR, history of AF, CHA2DS2VASc score, LA emptying fraction, LA indexed maximum volume, left ventricular ejection fraction, and indexed left ventricular mass (OR: 2.06 [95% CI: 1.08-3.92 per SD]; P = 0.027). By contrast, LA flow peak velocity was not significantly associated with LNCCIs (P = 0.21). No LA parameter was associated with lacunar infarcts (all P > 0.05). CONCLUSIONS: Reduced LA flow vorticity is significantly and independently associated with embolic brain infarcts. Imaging LA flow characteristics may aid identification of individuals who would benefit from anticoagulation for embolic stroke prevention, regardless of heart rhythm.


Subject(s)
Blood Circulation , Brain Infarction , Embolic Stroke , Heart Atria , Aged , Female , Humans , Male , Middle Aged , Atrial Fibrillation/epidemiology , Blood Circulation/physiology , Brain Infarction/epidemiology , Embolic Stroke/epidemiology , Heart Atria/diagnostic imaging , Heart Atria/physiopathology , Risk Factors
16.
Exp Clin Transplant ; 21(2): 83-92, 2023 02.
Article in English | MEDLINE | ID: mdl-36919717

ABSTRACT

OBJECTIVES: In the past decade, the implantable Doppler probe has been studied widely as a blood flow-monitoring device in reconstructive and transplant surgical specialities. Its utility as an effective postoperative monitoring technique is still debatable, with no clear guidelines in clinical practice. Here, we mapped the current evidence on the usefulness of the implantable Doppler probe as a blood flow-monitoring device. The objective was to present an up-to-date assessment of the benefits and limitations of using implantable Doppler probes in clinical and experimental clinical settings. MATERIALS AND METHODS: We conducted a literature search using the Cochrane Library and Healthcare Databases Advanced Search and using implantable Doppler probe, transplant, graft, and flap as key words. The search yielded 184 studies, with 73 studies included after exclusions. We evaluated, synthesized, and summarized the evidence from the studies in tabular form. RESULTS: There is clinical equipoise regarding the effectiveness of implantable Doppler probe as a flow sensing technique. The main reason is the lack of information and gaps in the evidence regarding the benefits and limitations of using implantable Doppler probes in clinical practice. CONCLUSIONS: The implantable Doppler probe has the potentialto be used as an adjunctpostoperativeblood flow-monitoring device. However, keeping in view of technical limitations, its signals should be interpreted alongside traditional clinical assessment techniques to determine the patency of microvascular anastomosis. Although evidence in this review will inform clinical practice in transplant and reconstructive surgical specialties, a prospective randomized controlled study with a larger patient cohort is required to evaluate the effectiveness of this probe in clinical settings.


Subject(s)
Monitoring, Physiologic , Regional Blood Flow , Surgical Flaps , Transplants , Ultrasonography, Doppler , Humans , Blood Circulation , Free Tissue Flaps/blood supply , Free Tissue Flaps/transplantation , Monitoring, Physiologic/instrumentation , Monitoring, Physiologic/methods , Plastic Surgery Procedures/instrumentation , Plastic Surgery Procedures/methods , Postoperative Period , Prospective Studies , Prostheses and Implants , Prosthesis Implantation/instrumentation , Prosthesis Implantation/methods , Surgical Flaps/blood supply , Transplantation/instrumentation , Transplantation/methods , Transplants/blood supply , Ultrasonography, Doppler/instrumentation , Ultrasonography, Doppler/methods
17.
Biomech Model Mechanobiol ; 22(3): 1095-1112, 2023 Jun.
Article in English | MEDLINE | ID: mdl-36869925

ABSTRACT

Biological tissues receive oxygen and nutrients from blood vessels by developing an indispensable supply and demand relationship with the blood vessels. We implemented a synthetic tree generation algorithm by considering the interactions between the tissues and blood vessels. We first segment major arteries using medical image data and synthetic trees are generated originating from these segmented arteries. They grow into extensive networks of small vessels to fill the supplied tissues and satisfy the metabolic demand of them. Further, the algorithm is optimized to be executed in parallel without affecting the generated tree volumes. The generated vascular trees are used to simulate blood perfusion in the tissues by performing multiscale blood flow simulations. One-dimensional blood flow equations were used to solve for blood flow and pressure in the generated vascular trees and Darcy flow equations were solved for blood perfusion in the tissues using a porous model assumption. Both equations are coupled at terminal segments explicitly. The proposed methods were applied to idealized models with different tree resolutions and metabolic demands for validation. The methods demonstrated that realistic synthetic trees were generated with significantly less computational expense compared to that of a constrained constructive optimization method. The methods were then applied to cerebrovascular arteries supplying a human brain and coronary arteries supplying the left and right ventricles to demonstrate the capabilities of the proposed methods. The proposed methods can be utilized to quantify tissue perfusion and predict areas prone to ischemia in patient-specific geometries.


Subject(s)
Algorithms , Blood Circulation , Computer Simulation , Blood Vessels , Humans , Animals , Brain/blood supply , Coronary Vessels/physiology , Cerebral Arteries/physiology , Datasets as Topic , Biomechanical Phenomena
18.
Anesthesiol Clin ; 41(1): 191-209, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36871999

ABSTRACT

Fluid therapy is an integral component of perioperative care and helps maintain or restore effective circulating blood volume. The principal goal of fluid management is to optimize cardiac preload, maximize stroke volume, and maintain adequate organ perfusion. Accurate assessment of volume status and volume responsiveness is necessary for appropriate and judicious utilization of fluid therapy. To accomplish this, static and dynamic indicators of fluid responsiveness have been widely studied. This review discusses the overarching goals of perioperative fluid management, reviews the physiology and parameters used to assess fluid responsiveness, and provides evidence-based recommendations on intraoperative fluid management.


Subject(s)
Blood Circulation , Fluid Therapy , Hemodynamics , Perioperative Care , Humans , Fluid Therapy/methods , Perioperative Care/methods , Stroke Volume/physiology , Blood Circulation/physiology , Hemodynamics/physiology , Cardiac Volume/physiology
19.
Brasília; CONITEC; mar. 2023.
Non-conventional in Portuguese | BRISA/RedTESA | ID: biblio-1433917

ABSTRACT

INTRODUÇÃO: O padrão ouro atual para monitorização hemodinâmica durante cirurgias é o cateter de artéria pulmonar, que exige punção venosa profunda. O FloTrac® é um sistema para monitorização hemodinâmica minimamente invasivo pois conecta-se à uma punção arterial distal, com potencial menor risco de complicações. TECNOLOGIA: Sensor pré-calibrado para monitorização hemodinâmica contínua do débito cardíaco e da pressão intravascular, sistema FloTrac. PERGUNTA: O uso do sistema FloTrac® em pacientes submetidos a procedimentos cirúrgicos de grande porte ou de alto risco é eficaz e seguro quando comparado ao uso do cateter de artéria pulmonar? EVIDÊNCIAS CIENTÍFICAS: As buscas identificaram apenas um ensaio clínico randomizado, cujo objetivo foi comparar o efeito da terapia guiada por metas realizada utilizando o cateter de artéria pulmonar versus o sistema FloTrac® após cirurgia de revascularização miocárdica. Os pacientes do grupo FloTrac® receberam mais volume e ficaram em média cinco horas a menos em suporte ventilatório, ambos desfechos estatisticamente significativos. Estudo com alto risco de viés e certeza da evidência avaliada como muito baixa. AVALIAÇÃO ECONÔMICA (AE): O demandante optou por descartar as diferenças observadas no ensaio clínico e considerar as tecnologias com igual eficácia, adotando um modelo econômico de custo-minimização. O preço do FloTrac® foi ofertado de forma a ser equivalente ao preço do cateter de artéria pulmonar em compras públicas recentes. A busca no Banco de Preços em Saúde foi atualizada pelo parecerista e observou-se que o preço proposto (R$ 1.200,00) está acima do valor SIGTAP (R$ 518,70) e da mediana de preços das compras públicas realizadas nos últimos 18 meses (R$ 358,50 a R$ 380,00 dependendo do tamanho do cateter). ANÁLISE DE IMPACTO ORÇAMENTÁRIO (AIO): A avaliação do impacto orçamentário foi realizada por demanda aferida e considerou apenas o custo de aquisição dos cateteres. O demandante considerou o mesmo preço para as tecnologias e consequentemente impacto orçamentário zero. O impacto foi recalculado com base na mediana e média ponderada dos preços atualizados no BPS em relação ao preço ofertado sendo constatado um impacto incremental em torno de 22,5 a 33,7 milhões de reais em cinco anos. RECOMENDAÇÕES DE AGÊNCIAS DE ATS: CONSIDERAÇÕES FINAIS: A monitorização minimamente invasiva é uma opção à monitorização invasiva com potencial, porém não comprovado, de redução de risco de complicações como infecção associada ao cateter e pneumotórax. Um único ensaio clínico, com muita baixa confiabilidade demonstrou superioridade do FloTrac® em relação ao cateter de artéria pulmonar com redução de cinco horas no tempo médio de ventilação assistida. O demandante optou por considerar eficácia semelhante e ofertar o FloTrac® com preço igual à mediana de preço de compras no BPS do cateter de artéria pulmonar, ou seja, sem custos incrementais ao SUS. Porém, os valores atualizados no BPS são inferiores aos valores apresentados. RECOMENDAÇÃO PRELIMINAR DA CONITEC: Pelo exposto, o Plenário da Conitec, em sua 114ª Reunião Ordinária, no dia 09 de novembro de 2022, deliberou por unanimidade que a matéria fosse disponibilizada em Consulta Pública com recomendação preliminar desfavorável à incorporação do FloTrac®, sistema para monitorização do débito cardíaco minimamente invasivo em cirurgias de grande porte e de alto risco. Os membros da Conitec consideraram que o preço da tecnologia é superior ao preço do cateter de artéria pulmonar hoje disponibilizado no SUS, o que é divergente da proposta apresentada pelo demandante de igualdade de preços e impacto orçamental nulo. Após revisão das compras realizadas nos últimos 18 meses, o preço proposto do FloTrac® (R$ 1.200,00), em relação ao preço do cateter de artéria pulmonar, encontra-se significativamente superior ao valor SIGTAP (R$ 518,70), média ponderada (R$ 380 a R$ 651,34 cateteres 7,0/7,5 french) ou mediana de preços (R$ 358,50 a R$ 380,00 cateteres 7,0/7,5 french) e que por isso causaria um impacto orçamentário incremental sem comprovação de benefícios clínicos ou de segurança que justificassem o investimento. CONSULTA PÚBLICA: Foram recebidas 7 contribuições, sendo todas de experiência e opinião. Diante das argumentações apresentadas, o plenário da Conitec entendeu que não houve argumentação suficiente para mudança de entendimento acerca de sua recomendação preliminar, com base em evidência científica frágil. Desse modo, a Comissão, diante das incertezas quanto ao real benefício do dispositivo, manteve a posição desfavorável à incorporação do sensor pré-calibrado para monitorização hemodinâmica contínua do débito cardíaco e da pressão intravascular, sistema FloTrac. RECOMENDAÇÃO FINAL DA CONITEC: Diante do exposto, os membros presentes do Comitê de Produtos e Procedimentos da Conitec, em sua 116ª Reunião Ordinária, realizada no dia 15 de março de 2023, deliberaram, por unanimidade, recomendar a não incorporação, no SUS, sensor pré-calibrado para monitorização de pressão intravascular e minimamente invasiva do débito cardíaco, FloTrac®, para cirurgias de grande porte e de alto risco. Para essa recomendação, a Conitec considerou que a consulta pública não trouxe elementos novos que alterassem a recomendação preliminar. Foi assinado o registro de deliberação nº 801/2023. DECISÃO: Não incorporar, no âmbito do Sistema Único de Saúde - SUS, o sensor pré-calibrado para monitorização de pressão intravascular e minimamente invasiva do débito cardíaco, FloTrac®, para cirurgias de grande porte e de alto risco, publicada no Diário Oficial da União nº 74, seção 1, página 195, em 18 de abril de 2023.


Subject(s)
Humans , Surgical Procedures, Operative/methods , Cardiac Output , Blood Pressure Monitors , Equipment and Supplies , Unified Health System , Blood Circulation , Brazil , Cost-Benefit Analysis/economics
20.
Ethiop. med. j. (Online) ; 61(1): 51-60, 2023. figures, tables
Article in English | AIM (Africa) | ID: biblio-1416377

ABSTRACT

Introduction: Dialysis still remains the most common modality for the treatment of end stage kidney disease and it could be maneuvered to augment its dose, minimize complications and improve outcome. Dialysis prescription is a brief of how dialysis is to be given and involves adjustments in patients' characteristics, disease or dialytic procedure. This study aimed to assess the determinants of the prescribed dialysis and its relationship with intradialytic complications and the dialysis dose. Methods: A prospective study in which 1248 sessions for 232 consented participants with end stage kidney disease on maintenance hemodialysis were studied from 2017-2020. Biodata was taken, participants were examined and blood samples were taken to determine electrolytes, urea/creatinine and hematocrit. Pearson's correlation was used to determine the strength of association between dialysis dose and some variables. Results: Determinants of the prescribed dose were dialysis frequency (P<0.001), and predialysis systolic blood pressure (P<0.001) and packed cell volume (P<0.001). Dialysis sessions without significant intradialytic blood pressure changes were most likely to be completed, as sessions with intra-dialysis hypotension were most likely to be terminated. Participants dialyzed with high flux dialyzers, via an arterovenous fistula, higher blood flow and ultrafiltration rates had higher dialysis doses (P<0.001 in all instances). Conclusion: Higher dialysis doses were achieved with higher blood flow and ultrafiltration rates. Intradialytic hypotension was common with dialysis termination, higher blood flow and ultrafiltration rates. Intradialytic hypertension was common with low flux dialyzers. An optimized dialysis prescription is needed to deliver an adequate dialysis dose and minimize complications


Subject(s)
Humans , Male , Female , Blood Circulation , Renal Dialysis , Dialysis , Prescriptions , Kidney Diseases , Therapeutics
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