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1.
JNMA J Nepal Med Assoc ; 59(238): 554-557, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34508397

RESUMO

INTRODUCTION: Laryngoscopy and intubation are stressful as they lead to a rise in heart rate and blood pressure. Though transient, it may be detrimental to the cardiac and neurosurgical patients. There is a need to explore the possibility of obtunding the pressor response to laryngoscopy and intubation with the use of McCoy blade laryngoscope. We aimed to find out the hemodynamic response to laryngoscopy and intubation using McCoy laryngoscope in adult patients undergoing general anesthesia. METHODS: The descriptive cross-sectional study was conducted in 37 American Society of Anesthesiologists' Physical Status I/IIpatients, with normal airway from December 2019- May 2020 in a tertiary care hospital. Ethical approval was obtained from Institutional Research Committee (reference number.: MEMG/IRC/290/GA). Convenience sampling method was used. The mean systolic and diastolic blood pressures were measured at baseline, one, three and five minutes after laryngoscopy and intubation. Data were analyzed using the Statistical Package for the Social Sciences Version 21.0. RESULTS: In the first minute after laryngoscopy and intubation, the rise in mean blood pressure was noted in 14 (37.83%) cases. The peak rise in mean blood pressure was 3%, note done minute after laryngoscopy and intubation. CONCLUSIONS: We noted better attenuation of pressor response to laryngoscopy and intubation using McCoy blade laryngoscope in adult patients undergoing general anesthesia.


Assuntos
Laringoscópios , Laringoscopia , Adulto , Estudos Transversais , Hemodinâmica , Humanos , Intubação Intratraqueal
2.
J Int Med Res ; 49(9): 3000605211042503, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34515575

RESUMO

The effects of increasing blood flow on the pathogenic wall shear stress (pWSS) of subclavian arteries (SAs) are currently unclear. Patient-specific models of the SA were constructed based on computed tomographic images from two patients. Using the Ansys Fluent 19.0 transient laminar flow solver, the finite volume method was chosen to solve the Navier-Stokes equation governing fluid behavior. The time-averaged wall shear stress, ratio of risk area, cumulative ratio of risk area (P¯), ratio of risk time, and ratio contour of risk time were calculated to describe the temporal and spatial distributions of pWSS. Virtually all pWSS occurred during the diastolic phase. The P¯ was 2.3 and 1.29 times higher on the left than on the right in Patients 1 (P1) and 2 (P2), respectively. Increasing the blood flow volume of the left SA by 20%, 40%, and 60% led to a 9.27%, 15.10%, and 20.99% decrease in P¯ for P1 and a 5.74%, 11.55%, and 17.14% decrease in P¯ for P2, respectively, compared with baseline values. In conclusion, the left SA showed greater diastolic pWSS than the right SA, and increasing the blood flow volume reduced the pWSS in the left SA.


Assuntos
Modelos Cardiovasculares , Artéria Subclávia , Velocidade do Fluxo Sanguíneo , Simulação por Computador , Hemodinâmica , Humanos , Estresse Mecânico , Artéria Subclávia/diagnóstico por imagem
3.
Sultan Qaboos Univ Med J ; 21(3): 403-407, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34522405

RESUMO

Objectives: Bicuspid aortic valve (BAV) is the most common congenital lesion found in adults. It can be seen in combination with a transverse left ventricular (LV) band. This study aimed to find an essential relationship between the presence of transverse ventricular band and BAV. Methods: A total of 13 patients from a tertiary care centre in India with transverse LV band were investigated during a six-month period from January 2019 to July 2019. LV band thickness and gradients at the site of the LV band were evaluated as part of its effect on LV haemodynamics. The morphology of the aortic valve and LV outflow tract gradients was assessed. Results: The mean age of the participants was 41 years. A majority had a BAV (n = 11). Average thickness of the LV band was 6.2 mm and the average mean aortic gradient was 4 mmHg. Sequestration of blood was noted at the level of the transverse band in all the patients with two separate jets at the left ventricular outflow tract. The anterolateral jet was deflected from the transverse band and showed higher velocity compared to the other jet, causing turbulence at the BAV. No correlation was found between the thickness of the transverse band and aortic valve gradient. Conclusion: Presence of a robust transverse LV band can serve as a surrogate marker for BAV.


Assuntos
Estenose da Valva Aórtica , Doença da Válvula Aórtica Bicúspide , Doenças das Valvas Cardíacas , Adulto , Valva Aórtica/cirurgia , Doenças das Valvas Cardíacas/diagnóstico , Hemodinâmica , Humanos
4.
Int J Mol Sci ; 22(15)2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34360913

RESUMO

Deficiency of the placental hormone chorionic somatomammotropin (CSH) can lead to the development of intrauterine growth restriction (IUGR). To gain insight into the physiological consequences of CSH RNA interference (RNAi), the trophectoderm of hatched blastocysts (nine days of gestational age; dGA) was infected with a lentivirus expressing either a scrambled control or CSH-specific shRNA, prior to transfer into synchronized recipient sheep. At 90 dGA, umbilical hemodynamics and fetal measurements were assessed by Doppler ultrasonography. At 120 dGA, pregnancies were fitted with vascular catheters to undergo steady-state metabolic studies with the 3H2O transplacental diffusion technique at 130 dGA. Nutrient uptake rates were determined and tissues were subsequently harvested at necropsy. CSH RNAi reduced (p ≤ 0.05) both fetal and uterine weights as well as umbilical blood flow (mL/min). This ultimately resulted in reduced (p ≤ 0.01) umbilical IGF1 concentrations, as well as reduced umbilical nutrient uptakes (p ≤ 0.05) in CSH RNAi pregnancies. CSH RNAi also reduced (p ≤ 0.05) uterine nutrient uptakes as well as uteroplacental glucose utilization. These data suggest that CSH is necessary to facilitate adequate blood flow for the uptake of oxygen, oxidative substrates, and hormones essential to support fetal and uterine growth.


Assuntos
Sangue Fetal/metabolismo , Retardo do Crescimento Fetal/genética , Retardo do Crescimento Fetal/metabolismo , Hemodinâmica/genética , Nutrientes/metabolismo , Lactogênio Placentário/deficiência , Lactogênio Placentário/genética , Interferência de RNA , Ovinos/genética , Transdução de Sinais/genética , Animais , Blastocisto/metabolismo , Feminino , Sangue Fetal/diagnóstico por imagem , Retardo do Crescimento Fetal/diagnóstico por imagem , Feto/metabolismo , Idade Gestacional , Glucose/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Masculino , Placenta/metabolismo , Gravidez , RNA Interferente Pequeno/genética , Ultrassonografia Doppler/métodos , Útero/metabolismo
6.
Med Klin Intensivmed Notfmed ; 116(6): 541-553, 2021 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-34338810

RESUMO

Circulatory shock requires treatment of the underlying pathology in addition to supportive pharmacological therapy that is guided by hemodynamic monitoring. Based on the evaluation of the patient's volume, perfusion and cardiac status, the following therapeutic goals should be achieved: (1) Normalization of the intra- and extravascular fluid volume. (2) Provision of sufficient perfusion pressure and organ perfusion. (3) Optimization of cardiac function including protecting an ischemic and exhausted myocardium from overload. The most important therapeutic substances are balanced electrolyte solutions and the vasopressor noradrenaline. Because there is little scientific evidence for the use of alternative drugs, these should only be given if there is a good pathophysiologic rationale and if their effect is continuously monitored and re-evaluated.


Assuntos
Choque , Hidratação , Hemodinâmica , Humanos , Monitorização Fisiológica , Norepinefrina , Choque/tratamento farmacológico , Vasoconstritores/efeitos adversos
7.
No Shinkei Geka ; 49(4): 888-897, 2021 Jul.
Artigo em Japonês | MEDLINE | ID: mdl-34376621

RESUMO

Since intracranial aneurysm(IA)is a disease that follows an extremely unpredictable course, from initiation to rupture, experimental models have greatly contributed to a better understanding of IA pathophysiology. This article aims to review the history of IA models through the pivotal theme of the ideal IA model. In addition, this article introduces updated findings from the application of these experimental models. Though the first IA model, known as a venous pouch model, was reported in 1954, it mimicked only the shape of the IA, without reproducing its pathological structure or blood-flow characteristics. Currently, two models are generally applied: the "Hashimoto model," produced by unilateral common carotid artery(CCA)ligation followed by systemic hypertension and weakening of the vascular wall, and the "elastase injection model," induced by intraventricular elastase injection and also followed by systemic hypertension. In addition, other models, including a rabbit basilar top IA, developed after bilateral CCA ligation, and an artificial bifurcation model, generated by an anastomosis between the CCAs, have been found to be valuable for computational fluid dynamics analysis. Through this advancement, the IA model has gradually elucidated the pathophysiology of IA as a flow-induced inflammatory disease. Nowadays, vascular inflammation is suggested to be regulated by bacterial flora. Further development of IA models and a better understanding of IA pathophysiology are expected in the future.


Assuntos
Aneurisma Intracraniano , Animais , Artéria Carótida Primitiva , Modelos Animais de Doenças , Hemodinâmica , Humanos , Hidrodinâmica , Modelos Teóricos , Coelhos
8.
Kardiologiia ; 61(7): 28-35, 2021 Jul 31.
Artigo em Russo, Inglês | MEDLINE | ID: mdl-34397339

RESUMO

Aim      To create a three-dimensional mathematical model of coronary flow in patients with ischemic heart disease based on findings of computed tomography angiography (CTA) with subsequent calculation of the fractional flow reserve (FFRCTA) and comparison of estimated FFRCTA with FFR reference values measured by coronary angiography (CAG).Material and methods  The study included 10 patients with borderline stenosis (50-75 %) as determined by CTA performed with a 640­slice CT-scanner. Based on CTA findings, three-dimensional mathematical models were constructed for further calculation of FFRCTA. Later, an invasive measurement of FFR (FFRINV) was performed for all patients. FFR values <0.8 indicated the hemodynamic significance of stenosis.Results FFRCTA and FFRINV values differed insignificantly in most cases (n=9) and exceeded 5% in only one case. The regression analysis showed a close correlation between estimated and invasively measured FFR values.Conclusion      Preliminary results showed a good consistency of calculated and measured FFR values. Therefore, further development of the method for mathematical modeling of three-dimensional blood flow by CTA findings is promising. Noninvasive evaluation of FFR is particularly relevant for analysis of hemodynamic significance of borderline (50-75 %) coronary stenoses.


Assuntos
Doença da Artéria Coronariana , Estenose Coronária , Reserva Fracionada de Fluxo Miocárdico , Angiografia por Tomografia Computadorizada , Computadores , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico , Estenose Coronária/diagnóstico por imagem , Hemodinâmica , Humanos , Valor Preditivo dos Testes , Tomografia Computadorizada por Raios X
9.
J Theor Biol ; 529: 110856, 2021 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-34363836

RESUMO

Blood Oxygen Level Dependent (BOLD) signal indirectly characterizes neuronal activity by measuring hemodynamic and metabolic changes in the nearby microvasculature. A deeper understanding of how localized changes in electrical, metabolic and hemodynamic factors translate into a BOLD signal is crucial for the interpretation of functional brain imaging techniques. While positive BOLD responses (PBR) are widely considered to be linked with neuronal activation, the origins of negative BOLD responses (NBR) have remained largely unknown. As NBRs are sometimes observed in close proximity of regions with PBR, a blood "stealing" effect, i.e., redirection of blood from a passive periphery to the area with high neuronal activity, has been postulated. In this study, we used the Hagen-Poiseuille equation to model hemodynamics in an idealized microvascular network that account for the particulate nature of blood and nonlinearities arising from the red blood cell (RBC) distribution (i.e., the Fåhraeus, Fåhraeus-Lindqvist and the phase separation effects). Using this detailed model, we evaluate determinants driving this "stealing" effect in a microvascular network with geometric parameters within physiological ranges. Model simulations predict that during localized cerebral blood flow (CBF) increases due to neuronal activation-hyperemic response, blood from surrounding vessels is reallocated towards the activated region. This stealing effect depended on the resistance of the microvasculature and the uneven distribution of RBCs at vessel bifurcations. A parsimonious model consisting of two-connected windkessel regions sharing a supplying artery was proposed to simulate the stealing effect with a minimum number of parameters. Comparison with the detailed model showed that the parsimonious model can reproduce the observed response for hematocrit values within the physiological range for different species. Our novel parsimonious model promise to be of use for statistical inference (top-down analysis) from direct blood flow measurements (e.g., arterial spin labeling and laser Doppler/Speckle flowmetry), and when combined with theoretical models for oxygen extraction/diffusion will help account for some types of NBRs.


Assuntos
Imageamento por Ressonância Magnética , Roubo , Encéfalo , Circulação Cerebrovascular , Hematócrito , Hemodinâmica , Oxigênio
10.
Comput Methods Programs Biomed ; 209: 106328, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34407452

RESUMO

BACKGROUND AND OBJECTIVE: Due to the relatively low fluid velocities in major arteries and veins, blood flow is by default laminar, however, turbulence can occur as a result of stenosis or other obstacles. Hemodynamic parameters like Wall Shear Stress or Oscillatory Shear Index can be used for plaque formation prediction, and these parameters are depended on the nature of the flow. Implementation of the k-ω turbulent flow in the Finite Element solver aims to improve numerical analysis of cardio-vascular condition development and progression. Calculation of turbulent fluid flow in this paper is performed using a two-equation turbulent finite element model that can calculate values in the viscous sublayer. METHODS: Implicit integration of the equations is used for determining the fluid velocity, turbulent kinetic energy and dissipation of turbulent kinetic energy. These values are calculated in the finite element nodes for each step of the incremental-iterative procedure. Developed turbulent finite element model with the customized generation of finite element meshes is used for calculating complex blood flow problems. RESULTS: Turbulent model is verified on an example of fluid flow in the backward-facing step channel and analysis results correspond well with the experimental ones from the literature. Further, a turbulent model is applied for the simulation of blood flow through artery bifurcation. Verification of numerical examples obtained using different commercial software packages (Ansys, COMSOL Multiphysics) ensuring usage and accuracy of PAK in-house solver. CONCLUSIONS: Analysis results show that turbulence cannot be neglected in the modelling of cardio-vascular conditions and that cardiologists can use the proposed tools and methods for investigating the hemodynamic conditions inside the bifurcation of arteries. Appropriate agreement between experimental results, and results obtained using commercial solutions and the k-ω turbulent flow in the Finite Element solver PAK, validate methodology presented in this paper. However, small deviations between the results underline the importance of the proper boundary condition prescription and mesh size and node distribution, which is also discussed in this paper. Due to the implicit integration implemented in PAK solver, time step size has an insignificant influence on the analysis results, assuming the initial time increments are sufficiently small to ensure proper discretization of velocity and pressure pulsatile functions.


Assuntos
Artérias , Hemodinâmica , Artérias/diagnóstico por imagem , Velocidade do Fluxo Sanguíneo , Simulação por Computador , Análise de Elementos Finitos , Modelos Cardiovasculares , Fluxo Pulsátil
11.
Physiol Rep ; 9(17): e14998, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34448551

RESUMO

The spread of the novel coronavirus 2019 (COVID-19) has caused a global pandemic. The disease has spread rapidly, and research shows that COVID-19 can induce long-lasting cardiac damage. COVID-19 can result in elevated cardiac biomarkers indicative of acute cardiac injury, and research utilizing echocardiography has shown that there is mechanical dysfunction in these patients as well, especially when observing the isovolumic, systolic, and diastolic portions of the cardiac cycle. The purpose of this study was to present two case studies on COVID-19 positive patients who had their cardiac mechanical function assessed every day during the acute period to show that cardiac function in these patients was altered, and the damage occurring can change from day-to-day. Participant 1 showed compromised cardiac function in the systolic time, diastolic time, isovolumic time, and the calculated heart performance index (HPI), and these impairments were sustained even 23 days post-symptom onset. Furthermore, Participant 1 showed prolonged systolic periods that lasted longer than the diastolic periods, indicative of elevated pulmonary artery pressure. Participant 2 showed decreases in systole and consequently, increases in HPI during the 3 days post-symptom onset, and these changes returned to normal after day 4. These results showed that daily observation of cardiac function can provide detailed information about the overall mechanism by which cardiac dysfunction is occurring and that COVID-19 can induce cardiac damage in unique patterns and thus can be studied on a case-by-case basis, day-to-day during infection. This could allow us to move toward more personalized cardiovascular medical treatment.


Assuntos
COVID-19/fisiopatologia , Cardiopatias/fisiopatologia , Coração/fisiopatologia , Hemodinâmica , SARS-CoV-2/patogenicidade , Função Ventricular , Adulto , COVID-19/diagnóstico , COVID-19/virologia , Técnicas de Diagnóstico Cardiovascular/instrumentação , Coração/virologia , Cardiopatias/diagnóstico , Cardiopatias/virologia , Interações Hospedeiro-Patógeno , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Fatores de Tempo , Transdutores
12.
Tex Heart Inst J ; 48(3)2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34388239

RESUMO

We studied whether sustained hemodynamic support (>7 d) with the Impella 5.0 heart pump can be used as a bridge to clinical decisions in patients who present with cardiogenic shock, and whether such support can improve their outcomes. We retrospectively reviewed cases of patients who had Impella 5.0 support at our hospital from August 2017 through May 2019. Thirty-four patients (23 with cardiogenic shock and 11 with severely decompensated heart failure) underwent sustained support for a mean duration of 11.7 ± 9.3 days (range, ≤48 d). Of 29 patients (85.3%) who survived to next therapy, 15 were weaned from the Impella, 8 underwent durable left ventricular assist device placement, 4 were escalated to venoarterial extracorporeal membrane oxygenation support, and 2 underwent heart transplantation. The 30-day survival rate was 76.5% (26 of 34 patients). Only 2 patients had a major adverse event: one each had an ischemic stroke and flail mitral leaflet. None of the devices malfunctioned. Sustained hemodynamic support with the Impella 5.0 not only improved outcomes in patients who presented with cardiogenic shock, but also provided time for multidisciplinary evaluation of potential cardiac recovery, or the need for durable left ventricular assist device implantation or heart transplantation. Our study shows the value of using the Impella 5.0 as a bridge to clinical decisions.


Assuntos
Insuficiência Cardíaca/terapia , Transplante de Coração , Coração Auxiliar , Hemodinâmica/fisiologia , Desenho de Equipamento , Oxigenação por Membrana Extracorpórea , Feminino , Seguimentos , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/fisiopatologia , Mortalidade Hospitalar/tendências , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Taxa de Sobrevida/tendências , Resultado do Tratamento , Estados Unidos/epidemiologia
13.
J Exp Biol ; 224(8)2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-34415043

RESUMO

Approximately half of all fishes have, in addition to the luminal venous O2 supply, a coronary circulation supplying the heart with fully oxygenated blood. Yet, it is not fully understood how coronary O2 delivery affects tolerance to environmental extremes such as warming and hypoxia. Hypoxia reduces arterial oxygenation, while warming increases overall tissue O2 demand. Thus, as both stressors are associated with reduced venous O2 supply to the heart, we hypothesised that coronary flow benefits hypoxia and warming tolerance. To test this hypothesis, we blocked coronary blood flow (via surgical coronary ligation) in rainbow trout (Oncorhynchus mykiss) and assessed how in vivo cardiorespiratory performance and whole-animal tolerance to acute hypoxia and warming was affected. While coronary ligation reduced routine stroke volume relative to trout with intact coronaries, cardiac output was maintained by an increase in heart rate. However, in hypoxia, coronary-ligated trout were unable to increase stroke volume to maintain cardiac output when bradycardia developed, which was associated with a slightly reduced hypoxia tolerance. Moreover, during acute warming, coronary ligation caused cardiac function to collapse at lower temperatures and reduced overall heat tolerance relative to trout with intact coronary arteries. We also found a positive relationship between individual hypoxia and heat tolerance across treatment groups, and tolerance to both environmental stressors was positively correlated with cardiac performance. Collectively, our findings show that coronary perfusion improves cardiac O2 supply and therefore cardiovascular function at environmental extremes, which benefits tolerance to natural and anthropogenically induced environmental perturbations.


Assuntos
Hemodinâmica , Oncorhynchus mykiss , Animais , Débito Cardíaco , Coração , Frequência Cardíaca , Hipóxia
14.
Int J Mol Sci ; 22(16)2021 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-34445328

RESUMO

Uteroplacental blood flow increases as pregnancy advances. Adequate supply of nutrients and oxygen carried by uteroplacental blood flow is essential for the well-being of the mother and growth/development of the fetus. The uteroplacental hemodynamic change is accomplished primarily through uterine vascular adaptation, involving hormonal regulation of myogenic tone, vasoreactivity, release of vasoactive factors and others, in addition to the remodeling of spiral arteries. In preeclampsia, hormonal and angiogenic imbalance, proinflammatory cytokines and autoantibodies cause dysfunction of both endothelium and vascular smooth muscle cells of the uteroplacental vasculature. Consequently, the vascular dysfunction leads to increased vascular resistance and reduced blood flow in the uteroplacental circulation. In this article, the (mal)adaptation of uteroplacental vascular function in normal pregnancy and preeclampsia and underlying mechanisms are reviewed.


Assuntos
Circulação Placentária/fisiologia , Pré-Eclâmpsia/fisiopatologia , Gravidez/fisiologia , Adaptação Fisiológica/fisiologia , Animais , Feminino , Hemodinâmica/fisiologia , Humanos , Placenta/irrigação sanguínea , Útero/irrigação sanguínea , Remodelação Vascular/fisiologia
15.
Cardiol Young ; 31(8): 1241-1250, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34378498

RESUMO

Fontan palliation represents one of the most remarkable surgical advances in the management of individuals born with functionally univentricular physiology. The operation secures adult survival for all but a few with unfavourable anatomy and/or physiology. Inherent to the physiology is passive transpulmonary blood flow, which produces a vulnerability to adequate filling of the systemic ventricle at rest and during exertion. Similarly, the upstream effects of passive flow in the lungs are venous congestion and venous hypertension, especially marked during physical activity. The pulmonary vascular bed has emerged as a defining character on the stage of Fontan circulatory behaviour and clinical outcomes. Its pharmacologic regulation and anatomic rehabilitation therefore seem important strategic therapeutic targets. This review seeks to delineate the important aspects of pulmonary artery development and maturation in functionally univentricular physiology patients, pulmonary artery biology, pulmonary vascular reserve with exercise, and pulmonary artery morphologic and pharmacologic rehabilitation.


Assuntos
Técnica de Fontan , Cardiopatias Congênitas , Cardiopatias Congênitas/cirurgia , Ventrículos do Coração/cirurgia , Hemodinâmica , Humanos , Pulmão , Artéria Pulmonar/cirurgia , Circulação Pulmonar
16.
J Anim Sci ; 99(9)2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34387666

RESUMO

The objectives were to examine melatonin-mediated changes in temporal uterine blood flow (UBF), vaginal temperatures (VTs), and fetal morphometrics in 54 commercial Brangus heifers (Fall, n = 29; Summer, n = 25) during compromised pregnancy. At day 160 of gestation, heifers were assigned to one of the four treatments consisting of adequately fed (ADQ-CON; 100% National Research Council [NRC]; n = 13), global nutrient restricted (RES-CON; 60% NRC; n =13), and ADQ or RES supplemented with 20 mg/d of melatonin (ADQ-MEL, n = 13; RES-MEL, n = 15). In the morning (0500 hours; AM) and afternoon (1300 hours; PM) of day 220 of gestation, UBF was determined via Doppler ultrasonography, while temperature data loggers attached to progesterone-free controlled internal drug releases were used to record VTs. At day 240 of gestation, heifers underwent cesarean sections for fetal removal and morphometrics determination. The UBF and VT data were analyzed using repeated measures of analysis of variance (ANOVA), while the morphometrics was analyzed using the MIXED procedure of SAS. Seasons were analyzed separately. In Fall, a nutrition by treatment interaction was observed, where the RES-CON heifers exhibited reduced total UBF compared with ADQ-CON (5.67 ± 0.68 vs. 7.97 ± 0.54 L/min; P = 0.039). In Summer, MEL heifers exhibited increased total UBF compared with the CON counterparts (8.16 ± 0.73 vs. 6.00 ± 0.70 L/min; P = 0.048). Moreover, there was a nutrition by treatment by time interaction in VT for Fall and Summer heifers (P ≤ 0.005). In Fall, all groups had decreased VT in the morning compared with the afternoon (P < 0.05). Whereas, in Summer, VT increased for ADQ-CON and RES-CON (P < 0.0001) from morning to afternoon, the ADQ-MEL and RES-MEL remained constant throughout the day (P = 0.648). Furthermore, the RES-MEL-PM exhibited decreased VT compared with ADQ-CON-PM (38.91 ± 0.09 vs. 39.26 ± 0.09 °C; P = 0.018). Lastly, in Fall, a main effect of nutrition was observed on fetal weights, where the RES dams had fetuses with decreased body weight when compared with ADQ (24.08 ± 0.62 vs. 26.57 ± 0.64 kg; P = 0.0087). In Summer, a nutrition by treatment interaction was observed on fetal weights where the RES-CON dams had fetuses with reduced weight when compared with ADQ-CON and RES-MEL (P < 0.05). In summary, nutrient restriction decreased UBF and melatonin supplementation increased UBF depending on the season. Additionally, melatonin appeared to decrease VT and rescue fetal weights when supplemented in the Summer.


Assuntos
Melatonina , Artéria Uterina , Animais , Bovinos , Feminino , Feto , Hemodinâmica , Melatonina/farmacologia , Nutrientes , Gravidez , Estações do Ano , Temperatura
17.
Medicine (Baltimore) ; 100(34): e27045, 2021 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-34449490

RESUMO

BACKGROUND: Laryngeal microsurgery (LMS) causes hemodynamic instability and postoperative agitation, cough, pain, nausea, and vomiting. Moreover, because of a short operation time, it is associated with challenging anesthetic management. The aim of this study was to compare the usefulness of continuous administration of dexmedetomidine and remifentanil in inducing general anesthesia in patients undergoing LMS. METHODS: This is a prospective randomized control design. Continuous intravenous infusion of dexmedetomidine (group D) or remifentanil (group R) was administered from 10 minutes before the induction of anesthesia to the end of surgery. In both groups, 1.5 mg/kg propofol and 0.5 mg/kg rocuronium were administered for the induction of anesthesia, and desflurane were titrated during the measurement of the bispectral index. We recorded hemodynamic data, recovery time, grade of cough, pain score, and analgesic requirements during the perioperative period. RESULTS: 61 patients were finally analyzed (30 for group D, 31 for group R). The incidence of moderate to severe postoperative sore throat was higher in group R than in group D (42% vs 10%, P = .008), and the quantity of rescue fentanyl used in post-anesthesia care unit was significantly higher in group R than in group D (23.2 ±â€Š24.7 mg vs 3.3 ±â€Š8.6 mg; P < .001); however, the time required for eye opening was significantly longer in group D than in group R (599.4 ±â€Š177.9 seconds vs 493.5 ±â€Š103.6 seconds; P = .006). The proportion of patients with no cough or single cough during extubation was comparable between the 2 groups (group D vs group R: 73% vs 70%) as was the incidence of hemodynamic instability. CONCLUSION: Although there was a transient delay in emergence time, dexmedetomidine reduced postoperative opioid use and the incidence of sore throat. Dexmedetomidine may be used as an alternative agent to opioids in patients undergoing LMS.


Assuntos
Dexmedetomidina/uso terapêutico , Hemodinâmica/efeitos dos fármacos , Hipnóticos e Sedativos/uso terapêutico , Laringe/cirurgia , Remifentanil/uso terapêutico , Adulto , Idoso , Analgésicos Opioides/administração & dosagem , Período de Recuperação da Anestesia , Tosse/etiologia , Feminino , Humanos , Masculino , Microcirurgia , Pessoa de Meia-Idade , Dor Pós-Operatória/tratamento farmacológico , Dor Pós-Operatória/epidemiologia , Dor Pós-Operatória/prevenção & controle , Período Perioperatório , Estudos Prospectivos , Índice de Gravidade de Doença , Adulto Jovem
18.
Theranostics ; 11(16): 7813-7828, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34335966

RESUMO

Non-invasive monitoring of hemodynamic tumor responses to chemotherapy could provide unique insights into the development of therapeutic resistance and inform therapeutic decision-making in the clinic. Methods: Here, we examined the longitudinal and dynamic effects of the common chemotherapeutic drug Taxotere on breast tumor (KPL-4) blood volume and oxygen saturation using eigenspectra multispectral optoacoustic tomography (eMSOT) imaging over a period of 41 days. Tumor vascular function was assessed by dynamic oxygen-enhanced eMSOT (OE-eMSOT). The obtained in vivo optoacoustic data were thoroughly validated by ex vivo cryoimaging and immunohistochemical staining against markers of vascularity and hypoxia. Results: We provide the first preclinical evidence that prolonged treatment with Taxotere causes a significant drop in mean whole tumor oxygenation. Furthermore, application of OE-eMSOT showed a diminished vascular response in Taxotere-treated tumors and revealed the presence of static blood pools, indicating increased vascular permeability. Conclusion: Our work has important translational implications and supports the feasibility of eMSOT imaging for non-invasive assessment of tumor microenvironmental responses to chemotherapy.


Assuntos
Neoplasias da Mama/metabolismo , Hemodinâmica/fisiologia , Tomografia Óptica/métodos , Animais , Neoplasias da Mama/diagnóstico por imagem , Linhagem Celular Tumoral , Docetaxel/farmacologia , Feminino , Hemodinâmica/efeitos dos fármacos , Humanos , Hipóxia/metabolismo , Camundongos , Camundongos SCID , Oxigênio/metabolismo , Técnicas Fotoacústicas/métodos , Tomografia/métodos , Tomografia Computadorizada por Raios X/métodos , Microambiente Tumoral/fisiologia
19.
Theriogenology ; 173: 173-182, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34392170

RESUMO

This study determined the ovarian, uterine, and luteal hemodynamic variations using Doppler between pregnant and non-pregnant pluriparous buffalos in relation to their anatomical and histological basics during the first 31 days after natural mating. Adult healthy cyclic Egyptian buffalo (n = 10) were selected and categorized into two groups; group 1 (n = 5) was mated naturally by a fertile bull during the late estrus phase, and group 2 (n = 5) was not mated. Animals were subjected to Doppler ultrasonography to evaluate luteal, ovarian, and uterine blood flows from day 7 until day 31 post-mating. Besides, three pregnant (one month) and other non-pregnant uterus (n = 6) were obtained from a local abattoir to study the anatomical and histological features. Our results revealed that the luteal, ovarian, and uterine arteries cross-sectional diameters/mm increased (P < 0.05) from day 7 till day 31. Resistance (RI) and pulsatility indices (PI) decreased linearly (P < 0.05) in pregnant buffalos till day 31, but the peak systolic, end diastolic velocities and flow volume of those arteries were increased. Additionally, luteal colored areas away and toward CL were increased (P < 0.05) in the pregnant group compared to non-pregnant ones. There was a significant (P < 0.05) increase in the lumen diameter of luteal, ovarian, and uterine artery sections in pregnant buffalos compared to those of non-pregnant ones. While the mean value of tunica media's thickness of both luteal and uterine artery was significantly higher in non-pregnant buffalos than pregnant ones, except for that of the ovarian artery. Additionally, the ovarian and uterine artery tunica muscularis relative area % was (P < 0.05) higher in pregnant buffalos than in non-pregnant ones, except for that of the luteal artery. It was concluded that in pregnant buffalos, ovarian, uterine, and luteal blood flows were improved from the first week until 31 days post-mating via a decline in both Doppler indices with an increase in Doppler velocities and blood flow volume in relation to their histological changes based on their anatomical architecture in comparison to non-pregnant one.


Assuntos
Búfalos , Útero , Animais , Velocidade do Fluxo Sanguíneo , Egito , Feminino , Hemodinâmica , Masculino , Gravidez , Útero/diagnóstico por imagem
20.
BMC Res Notes ; 14(1): 325, 2021 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-34429149

RESUMO

OBJECTIVE: We performed a single-center double-blinded, randomized trial to investigate the hemodynamic effects of IV paracetamol in patients with chronic liver disease (CLD) undergoing liver transplantation surgery. Patients with CLD are particularly susceptible to hemodynamic derangements given their low systemic vascular resistance state. Accordingly, hypotension is common in this setting. The hemodynamic effects of IV paracetamol in patients undergoing elective liver transplantation are unknown, therefore we evaluated whether the intraoperative administration of IV paracetamol in patients with chronic liver disease undergoing liver transplantation results in adverse hemodynamic effects. The primary end point was a change in systolic blood pressure 30-min after the preoperative infusion. RESULTS: Twenty-four participants undergoing liver transplantation surgery were randomly assigned to receive a single bolus of IV paracetamol (1 g paracetamol + 3.91 g mannitol per 100 mL) (n = 12) or placebo (0.9% Saline 100 mL) (n = 12). All participants completed their study intervention, and there were no breaches or violations of the trial protocol. Baseline characteristics were similar in both groups. There were no significant differences regarding surgical duration, intraoperative use of fluids, and intraoperative noradrenaline use. After the administration of paracetamol there were no significant differences observed in blood pressure or other hemodynamic parameters when compared to placebo.


Assuntos
Hepatopatias , Transplante de Fígado , Acetaminofen , Hemodinâmica , Humanos , Projetos Piloto
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