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1.
Medicine (Baltimore) ; 100(6): e23570, 2021 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-33578509

RESUMO

ABSTRACT: The Gas Man simulation software provides an opportunity to teach, understand and examine the pharmacokinetics of volatile anesthetics. The primary aim of this study was to investigate the accuracy of a cardiac output and alveolar ventilation matched Gas Man model and to compare its predictive performance with the standard pharmacokinetic model using patient data.Therefore, patient data from volatile anesthesia were successively compared to simulated administration of desflurane and sevoflurane for the standard and a parameter-matched simulation model with modified alveolar ventilation and cardiac output. We calculated the root-mean-square deviation (RMSD) between measured and calculated induction, maintenance and elimination and the expiratory decrement times during emergence and recovery for the standard and the parameter-matched model.During induction, RMSDs for the standard Gas Man simulation model were higher than for the parameter-matched Gas Man simulation model [induction (desflurane), standard: 1.8 (0.4) % Atm, parameter-matched: 0.9 (0.5) % Atm., P = .001; induction (sevoflurane), standard: 1.2 (0.9) % Atm, parameter-matched: 0.4 (0.4) % Atm, P = .029]. During elimination, RMSDs for the standard Gas Man simulation model were higher than for the parameter-matched Gas Man simulation model [elimination (desflurane), standard: 0.7 (0.6) % Atm, parameter-matched: 0.2 (0.2) % Atm, P = .001; elimination (sevoflurane), standard: 0.7 (0.5) % Atm, parameter-matched: 0.2 (0.2) % Atm, P = .008]. The RMSDs during the maintenance of anesthesia and the expiratory decrement times during emergence and recovery showed no significant differences between the patient and simulated data for both simulation models.Gas Man simulation software predicts expiratory concentrations of desflurane and sevoflurane in humans with good accuracy, especially when compared to models for intravenous anesthetics. Enhancing the standard model by ventilation and hemodynamic input variables increases the predictive performance of the simulation model. In most patients and clinical scenarios, the predictive performance of the standard Gas Man simulation model will be high enough to estimate pharmacokinetics of desflurane and sevoflurane with appropriate accuracy.


Assuntos
Débito Cardíaco/efeitos dos fármacos , Desflurano/farmacocinética , Expiração/fisiologia , Ventilação Pulmonar/fisiologia , Sevoflurano/farmacocinética , Adulto , Idoso , Algoritmos , Anestésicos Inalatórios/administração & dosagem , Anestésicos Inalatórios/farmacocinética , Débito Cardíaco/fisiologia , Ensaios Clínicos como Assunto , Simulação por Computador/estatística & dados numéricos , Desflurano/administração & dosagem , Quimioterapia Combinada , Feminino , Humanos , Pulmão/metabolismo , Pulmão/fisiologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Alvéolos Pulmonares/efeitos dos fármacos , Alvéolos Pulmonares/metabolismo , Alvéolos Pulmonares/fisiologia , Sevoflurano/administração & dosagem
2.
BMC Infect Dis ; 21(1): 208, 2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33632141

RESUMO

BACKGROUND: Hand, foot, and mouth disease (HFMD) is an acute infectious disease caused by human enterovirus 71 (EV71), coxsackievirus, or echovirus, which is particularly common in preschool children. Severe HFMD is prone to cause pulmonary edema before progressing to respiratory and circulatory failure; thus hemodynamic monitoring and fluid management are important to the treatment process. METHODS: We did a review of young patients who had been successfully treated in our department for severe HFMD, which had been caused by EV71. A total of 20 patients met the inclusion criteria. Eight cases were monitored by the pulse indicator continuous cardiac output (PiCCO) technique, and fluid management was administered according to its parameters. With regard to the treatment with PiCCO monitoring, patients were divided into two groups: the PiCCO group (8 patients) and the control group (12 patients). The groups were then compared comprehensively to evaluate whether PiCCO monitoring could improve patients' clinical outcomes. RESULTS: After analysis, the findings informed that although PiCCO failed to shorten the length of ICU stay, reduce the days of vasoactive drug usage, or lower the number of cases which required mechanical ventilation, PiCCO did reduce the incidence of fluid overload (p = 0.085) and shorten the days of mechanical ventilation (p = 0.028). After effective treatment, PiCCO monitoring indicated that the cardiac index (CI) increased gradually(p < 0.0001), in contrast to their pulse (P, p < 0.0001), the extra vascular lung water index (EVLWI, p < 0.0001), the global end diastolic volume index (GEDVI, p = 0.0043), and the systemic vascular resistance index (SVRI, p < 0.0001), all of which decreased gradually. CONCLUSION: Our study discovered that PiCCO hemodynamic monitoring in young children with severe HFMD has some potential benefits, such as reducing fluid overload and the duration of mechanical ventilation. However, whether it can ameliorate the severity of the disease, reduce mortality, or prevent multiple organ dysfunction remain to be further investigated.


Assuntos
Hidratação , Doença de Mão, Pé e Boca/fisiopatologia , Doença de Mão, Pé e Boca/terapia , Hemodinâmica/fisiologia , Monitorização Fisiológica/métodos , Débito Cardíaco/fisiologia , Pré-Escolar , Enterovirus Humano A/isolamento & purificação , Feminino , Doença de Mão, Pé e Boca/diagnóstico , Frequência Cardíaca/fisiologia , Humanos , Lactente , Masculino , Edema Pulmonar/diagnóstico , Edema Pulmonar/fisiopatologia , Edema Pulmonar/terapia , Estudos Retrospectivos , Resultado do Tratamento
3.
Br J Anaesth ; 126(4): 818-825, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33632521

RESUMO

BACKGROUND: We designed a prospective sub-study of the larger Restrictive versus Liberal Fluid Therapy in Major Abdominal Surgery (RELIEF) trial to measure differences in stroke volume and other haemodynamic parameters at the end of the intraoperative fluid protocols. The haemodynamic effects of the two fluid regimens may increase our understanding of the observed perioperative outcomes. METHODS: Stroke volume and cardiac output were measured with both an oesophageal Doppler ultrasound monitor and arterial pressure waveform analysis. Stroke volume variation, pulse pressure variation, and plethysmographic variability index were also obtained. A passive leg raise manoeuvre was performed to identify fluid responsiveness. RESULTS: Analysis of 105 patients showed that the primary outcome, Doppler monitor-derived stroke volume index, was higher in the liberal group: restrictive 38.5 (28.6-48.8) vs liberal 44.0 (34.9-61.9) ml m-2; P=0.043. Similarly, there was a higher cardiac index in the liberal group: 2.96 (2.32-4.05) vs 2.42 (1.94-3.26) L min-1 m-2; P=0.015. Arterial-pressure-based stroke volume and cardiac index did not differ, nor was there a significant difference in stroke volume variation, pulse pressure variation, or plethysmographic variability index. The passive leg raise manoeuvre showed fluid responsiveness in 40% of restrictive and 30% of liberal protocol patients (not significant). CONCLUSIONS: The liberal fluid group from the RELIEF trial had significantly higher Doppler ultrasound monitor-derived stroke volume and cardiac output compared with the restrictive fluid group at the end of the intraoperative period. Measures of fluid responsiveness did not differ significantly between groups. CLINICAL TRIAL REGISTRATION: ACTRN12615000125527.


Assuntos
Débito Cardíaco/fisiologia , Procedimentos Cirúrgicos do Sistema Digestório/efeitos adversos , Hidratação/métodos , Monitorização Intraoperatória/métodos , Complicações Pós-Operatórias/prevenção & controle , Volume Sistólico/fisiologia , Adulto , Idoso , Procedimentos Cirúrgicos do Sistema Digestório/tendências , Feminino , Hidratação/tendências , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Intraoperatória/tendências , Complicações Pós-Operatórias/diagnóstico por imagem , Estudos Prospectivos , Resultado do Tratamento , Ultrassonografia Doppler/métodos , Ultrassonografia Doppler/tendências
4.
Medicine (Baltimore) ; 100(7): e24722, 2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33607814

RESUMO

ABSTRACT: Excessive iron accumulation provokes toxic effects, especially in the cardiovascular system. Under iron overload, labile free non-transferrin-bound iron (NTBI) can induce cardiovascular damage with increased oxidative stress. However, the significance of NTBI in individuals without iron overload and overt cardiovascular disease has not been investigated. We aimed to examine the distribution of serum NTBI and its relationship with oxidative stress and cardiac load under physiological conditions in the general population.We enrolled individuals undergoing an annual health check-up and measured serum NTBI and derivatives of reactive oxygen metabolites (d-ROM), an oxidative stress marker. In addition, we evaluated serum levels of B-type natriuretic peptide (BNP) to examine cardiac load. We excluded patients with anemia, renal dysfunction, cancer, active inflammatory disease, or a history of cardiovascular disease.A total of 1244 individuals (57.8 ±â€Š11.8 years) were enrolled, all of whom had detectable serum NTBI. d-ROM and BNP showed significant trends across NTBI quartiles. Multivariable regression analysis revealed that serum iron and low-density lipoprotein cholesterol were positively associated with NTBI but that age, d-ROM, and BNP showed an inverse association with this measure. In logistic regression analysis, NTBI was independently associated with a combination of higher levels of both d-ROM and BNP than the upper quartiles after adjustment for possible confounding factors.Serum NTBI concentration is detectable in the general population and shows significant inverse associations with oxidative stress and cardiac load. These findings indicate that serum NTBI in physiological conditions does not necessarily reflect increased oxidative stress, in contrast to the implications of higher levels in states of iron overload or pathological conditions.


Assuntos
Débito Cardíaco/fisiologia , Sistema Cardiovascular/metabolismo , Sobrecarga de Ferro/complicações , Ferro/sangue , Estresse Oxidativo/fisiologia , Idoso , Sistema Cardiovascular/fisiopatologia , Estudos Transversais , Feminino , Ferritinas/sangue , Humanos , Lipoproteínas LDL/sangue , Masculino , Pessoa de Meia-Idade , Peptídeo Natriurético Encefálico/sangue , Transferrina/análise
5.
Medicine (Baltimore) ; 100(1): e24181, 2021 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-33429806

RESUMO

ABSTRACT: To determine whether the change in the number of pulmonary ultrasound B-line can accurately assess the extravascular lung water (EVLW) before and after continuous bedside blood purification (CBP) in patients with multiple organ dysfunction syndrome (MODS).Seventy-six patients with MODS who underwent CBP were examined within 24 hours before and after CBP using pulmonary ultrasound to detect the number of ultrasound B-line or using pulse indicator continuous cardiac output method to examine extravascular lung water, blood oxygenation index, and B-type natriuretic peptide (BNP) content. The correlation of the change in the number of B lines before and after CBP treatment with the negative balance of 24 hours liquid, the change of oxygenation index, and BNP content were analyzed.In the 76 patients, CBP treatment significantly decreased EVLW, the number of B-line, and BNP (P < .05 for all), while it significantly increased the oxygenation index (P < .05). Correlation analysis showed that the decrease in B-line number after CBP treatment was positively correlated with the 24 hours negative lung fluid balance, decrease of EVLW, oxygenation index improvement, and decreased BNP content. The change in the numbers of pulmonary ultrasound B-line can accurately assess the change of EVLW before and after CBP treatment and reflect the efficiency of ventilation in the lungs and the risk of heart failure.Thus, it can replace pulse indicator continuous cardiac output as an indicator for evaluating EVLW in patients with MODS treated with CBP.


Assuntos
Água Extravascular Pulmonar/diagnóstico por imagem , Pulmão/diagnóstico por imagem , Insuficiência de Múltiplos Órgãos/diagnóstico por imagem , Ultrassonografia/métodos , Adulto , Débito Cardíaco/fisiologia , Água Extravascular Pulmonar/fisiologia , Feminino , Determinação da Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade
6.
J Appl Physiol (1985) ; 130(3): 865-876, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33439790

RESUMO

COVID-19 infection may lead to acute respiratory distress syndrome (CARDS) where severe gas exchange derangements may be associated, at least in the early stages, only with minor pulmonary infiltrates. This may suggest that the shunt associated to the gasless lung parenchyma is not sufficient to explain CARDS hypoxemia. We designed an algorithm (VentriQlar), based on the same conceptual grounds described by J.B. West in 1969. We set 498 ventilation-perfusion (VA/Q) compartments and, after calculating their blood composition (PO2, PCO2, and pH), we randomly chose 106 combinations of five parameters controlling a bimodal distribution of blood flow. The solutions were accepted if the predicted PaO2 and PaCO2 were within 10% of the patient's values. We assumed that the shunt fraction equaled the fraction of non-aerated lung tissue at the CT quantitative analysis. Five critically-ill patients later deceased were studied. The PaO2/FiO2 was 91.1 ± 18.6 mmHg and PaCO2 69.0 ± 16.1 mmHg. Cardiac output was 9.58 ± 0.99 L/min. The fraction of non-aerated tissue was 0.33 ± 0.06. The model showed that a large fraction of the blood flow was likely distributed in regions with very low VA/Q (Qmean = 0.06 ± 0.02) and a smaller fraction in regions with moderately high VA/Q. Overall LogSD, Q was 1.66 ± 0.14, suggestive of high VA/Q inequality. Our data suggest that shunt alone cannot completely account for the observed hypoxemia and a significant VA/Q inequality must be present in COVID-19. The high cardiac output and the extensive microthrombosis later found in the autopsy further support the hypothesis of a pathological perfusion of non/poorly ventilated lung tissue.NEW & NOTEWORTHY Hypothesizing that the non-aerated lung fraction as evaluated by the quantitative analysis of the lung computed tomography (CT) equals shunt (VA/Q = 0), we used a computational approach to estimate the magnitude of the ventilation-perfusion inequality in severe COVID-19. The results show that a severe hyperperfusion of poorly ventilated lung region is likely the cause of the observed hypoxemia. The extensive microthrombosis or abnormal vasodilation of the pulmonary circulation may represent the pathophysiological mechanism of such VA/Q distribution.


Assuntos
/fisiopatologia , Relação Ventilação-Perfusão/fisiologia , Adulto , Idoso , Débito Cardíaco/fisiologia , Feminino , Hemodinâmica/fisiologia , Humanos , Pulmão/metabolismo , Pulmão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Oxigênio/metabolismo , Perfusão/métodos , Circulação Pulmonar/fisiologia , Troca Gasosa Pulmonar/fisiologia , Respiração , Estudos Retrospectivos , /patogenicidade
7.
Medicine (Baltimore) ; 99(51): e23764, 2020 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-33371141

RESUMO

ABSTRACT: Passive leg raising (PLR) is a convenient and reliable test to predict fluid responsiveness. The ability of thoracic electrical bioimpedance cardiography (TEB) to monitor changes of cardiac output (CO) during PLR is unknown.In the present study, we measured CO in 61 patients with shock or dyspnea by TEB and transthoracic echocardiography (TTE) during PLR procedure. Positive PLR responsiveness was defined as the velocity-time integral (VTI) ≥10% after PLR. TTE measured VTI in the left ventricular output tract. The predictive value of TEB parameters in PLR responders was tested. Furthermore, the agreement of absolute CO values between TEB and TTE measurements was assessed.Among the 61 patients, there were 28 PLR-responders and 33 non-responders. Twenty-seven patients were diagnosed with shock and 34 patients with dyspnea, with 55.6% (15/27) and 54.6% (18/34) non-responders, respectively. A change in TEB measured CO (ΔCO) ≥9.8% predicted PLR responders with 75.0% sensitivity and 78.8% specificity, the area under the receiver operating characteristic curve (AUROC) was 0.79. The Δd2Z/dt2 (a secondary derivative of the impedance wave) showed the best predictive value with AUROC of 0.90, the optimal cut point was -7.1% with 85.7% sensitivity and 87.9% specificity. Bias between TEB and TTE measured CO was 0.12 L/min, and the percentage error was 65.8%.TEB parameters had promising performance in predicting PLR responders, and the Δd2Z/dt2 had the best predictive value. The CO values measured by TEB were not interchangeable with TTE in critically ill settings.


Assuntos
Débito Cardíaco/fisiologia , Cardiografia de Impedância/instrumentação , Hemodinâmica/fisiologia , Adulto , Idoso , Área Sob a Curva , Cardiografia de Impedância/métodos , China , Estado Terminal , Ecocardiografia/métodos , Feminino , Humanos , Unidades de Terapia Intensiva/organização & administração , Unidades de Terapia Intensiva/tendências , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Curva ROC , Estatísticas não Paramétricas
8.
Ann Afr Med ; 19(3): 188-190, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32820731

RESUMO

Introduction: Proportional Pulse Pressure (PPP) is a significant risk indicator in heart failure. PPP is a simple, inexpensive and easily measurable clinical index. This non-invasive test provides useful prognostic information for patients with heart failure with reduced ejection fraction (EF) particularly in those with an EF < 30% where lower proportional pulse pressure independently predicts mortality. Methods: A prospective observational study involving 150 patients with reduced ejection fraction was done. Detailed history, clinical examination and parameters like pulse pressure, proportional pulse pressure were evaluated and correlated with ejection fraction. Results: The mean age of the patients was 58.99 ± 11.03 years and the majority of the study participants (57.33 %) were between 45 and 65 years of age. The most common etiology of heart failure (HF) was coronary heart disease in this study (76%). Proportional Pulse pressure showed significant association with ejection fraction. The specificity for detecting heart failure was more for proportional pulse pressure and systolic blood pressure (95 % each). Conclusion: Proportional Pulse Pressure may help to identify HF patients who present with low cardiac output, low ejection fraction, and worse prognosis. Our current observations reinforce the importance of clinically based skills that must not be forgotten when managing HF.


Assuntos
Pressão Sanguínea/fisiologia , Débito Cardíaco/fisiologia , Insuficiência Cardíaca/fisiopatologia , Volume Sistólico/fisiologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Fatores de Risco , Índice de Gravidade de Doença
10.
Am J Cardiol ; 133: 139-147, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-32838928

RESUMO

Ventricular septal defects (VSDs) have recently demonstrated poorer functional outcome with disrupted ventricular contractility during exercise in young patients. It is not known whether this will change with age. Therefore, echocardiography was performed in older patients with congenital VSDs, either surgically closed or unrepaired and all without Eisenmenger physiology, to compare functional outcomes with healthy peers. Transthoracic echocardiography was performed at rest and during supine bicycle exercise, with tissue velocity Doppler for assessment of primary end points: isovolumetric acceleration and systolic velocities. In total, 30 surgically closed VSDs (51 ± 8 years) with 30 healthy controls (52 ± 9 years) and 30 unrepaired VSDs (55 ± 12 years) with 30 matched controls (55 ± 10 years) were included. Surgical patients displayed lower right ventricular (RV) systolic and early diastolic-filling velocities compared with controls, p <0.01, lower tricuspid annular plane systolic excursion (17.8 ± 5 vs 22.7 ± 3mm, p <0.01) and lower fractional area change (37.8 ± 6 vs 46.4% ± 7%, p <0.01). Unrepaired VSDs also had lower RV fractional area change than matched controls (39.9 ± 7 vs 48.4% ± 7%, p <0.01). Both patient groups had more tricuspid regurgitation and larger RV outflow tract dimensions than controls, p <0.01. During exercise, isovolumetric acceleration and systolic velocities were lower in both patient groups compared with controls, with the difference increasing with workload level. In conclusion, adults in their mid-50s with surgically closed or unrepaired VSDs have abnormal RV function at rest, with even more pronounced differences during exercise. These results suggest that a VSD, whether repaired early or considered hemodynamically insignificant, is not a benign lesion and continuous follow-up of adults is warranted.


Assuntos
Débito Cardíaco/fisiologia , Comunicação Interventricular/fisiopatologia , Comunicação Interventricular/cirurgia , Adulto , Fatores Etários , Velocidade do Fluxo Sanguíneo/fisiologia , Estudos de Casos e Controles , Ecocardiografia Doppler , Teste de Esforço , Feminino , Comunicação Interventricular/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Função Ventricular Direita/fisiologia
11.
Br J Anaesth ; 125(2): 122-132, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32711724

RESUMO

BACKGROUND: Despite several clinical trials on haemodynamic therapy, the optimal intraoperative haemodynamic management for high-risk patients undergoing major abdominal surgery remains unclear. We tested the hypothesis that personalised haemodynamic management targeting each individual's baseline cardiac index at rest reduces postoperative morbidity. METHODS: In this single-centre trial, 188 high-risk patients undergoing major abdominal surgery were randomised to either routine management or personalised haemodynamic management requiring clinicians to maintain personal baseline cardiac index (determined at rest preoperatively) using an algorithm that guided intraoperative i.v. fluid and/or dobutamine administration. The primary outcome was a composite of major complications (European Perioperative Clinical Outcome definitions) or death within 30 days of surgery. Secondary outcomes included postoperative morbidity (assessed by a postoperative morbidity survey), hospital length of stay, mortality within 90 days of surgery, and neurocognitive function assessed after postoperative Day 3. RESULTS: The primary outcome occurred in 29.8% (28/94) of patients in the personalised management group, compared with 55.3% (52/94) of patients in the routine management group (relative risk: 0.54, 95% confidence interval [CI]: 0.38 to 0.77; absolute risk reduction: -25.5%, 95% CI: -39.2% to -11.9%; P<0.001). One patient assigned to the personalised management group, compared with five assigned to the routine management group, died within 30 days after surgery (P=0.097). There were no clinically relevant differences between the two groups for secondary outcomes. CONCLUSIONS: In high-risk patients undergoing major abdominal surgery, personalised haemodynamic management reduces a composite outcome of major postoperative complications or death within 30 days after surgery compared with routine care. CLINICAL TRIAL REGISTRATION: NCT02834377.


Assuntos
Abdome/cirurgia , Débito Cardíaco/fisiologia , Hidratação/métodos , Hemodinâmica/fisiologia , Cuidados Intraoperatórios/métodos , Complicações Pós-Operatórias/prevenção & controle , Idoso , Feminino , Humanos , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/fisiopatologia , Estudos Prospectivos , Risco
13.
Br J Anaesth ; 125(1): 25-37, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32475686

RESUMO

BACKGROUND: Finger cuff technologies allow continuous noninvasive arterial blood pressure (AP) and cardiac output/index (CO/CI) monitoring. METHODS: We performed a meta-analysis of studies comparing finger cuff-derived AP and CO/CI measurements with invasive measurements in surgical or critically ill patients. We calculated overall random effects model-derived pooled estimates of the mean of the differences and of the percentage error (PE; CO/CI studies) with 95%-confidence intervals (95%-CI), pooled 95%-limits of agreement (95%-LOA), Cochran's Q and I2 (for heterogeneity). RESULTS: The pooled mean of the differences (95%-CI) was 4.2 (2.8 to 5.62) mm Hg with pooled 95%-LOA of -14.0 to 22.5 mm Hg for mean AP (Q=230.4 [P<0.001], I2=91%). For mean AP, the mean of the differences between finger cuff technologies and the reference method was ≤5±8 mm Hg in 9/27 data sets (33%). The pooled mean of the differences (95%-CI) was -0.13 (-0.43 to 0.18) L min-1 with pooled 95%-LOA of -2.56 to 2.23 L min-1 for CO (Q=66.7 [P<0.001], I2=90%) and 0.07 (0.01 to 0.13) L min-1 m-2 with pooled 95%-LOA of -1.20 to 1.15 L min-1 m-2 for CI (Q=5.8 [P=0.326], I2=0%). The overall random effects model-derived pooled estimate of the PE (95%-CI) was 43 (37 to 49)% (Q=48.6 [P<0.001], I2=63%). In 4/19 data sets (21%) the PE was ≤30%, and in 10/19 data sets (53%) it was ≤45%. CONCLUSIONS: Study heterogeneity was high. Several studies showed interchangeability between AP and CO/CI measurements using finger cuff technologies and reference methods. However, the pooled results of this meta-analysis indicate that AP and CO/CI measurements using finger cuff technologies and reference methods are not interchangeable in surgical or critically ill patients. CLINICAL TRIAL NUMBER: PROSPERO registration number: CRD42019119266.


Assuntos
Pressão Arterial/fisiologia , Determinação da Pressão Arterial/métodos , Débito Cardíaco/fisiologia , Cuidados Críticos/métodos , Assistência Perioperatória/métodos , Análise de Onda de Pulso/métodos , Determinação da Pressão Arterial/instrumentação , Dedos , Humanos
14.
Yonsei Med J ; 61(6): 482-491, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32469172

RESUMO

PURPOSE: Cardiac power (CP) index is a product of mean arterial pressure (MAP) and cardiac output (CO). In aortic stenosis, however, MAP is not reflective of true left ventricular (LV) afterload. We evaluated the utility of a gradient-adjusted CP (GCP) index in predicting survival after transcatheter aortic valve replacement (TAVR), compared to CP alone. MATERIALS AND METHODS: We included 975 patients who underwent TAVR with 1 year of follow-up. CP was calculated as (CO×MAP)/[451×body surface area (BSA)] (W/m²). GCP was calculated using augmented MAP by adding aortic valve mean gradient (AVMG) to systolic blood pressure (CP1), adding aortic valve maximal instantaneous gradient to systolic blood pressure (CP2), and adding AVMG to MAP (CP3). A multivariate Cox regression analysis was performed adjusting for baseline covariates. Receiver operator curves (ROC) for CP and GCP were calculated to predict survival after TAVR. RESULTS: The mortality rate at 1 year was 16%. The mean age and AVMG of the survivors were 81±9 years and 43±4 mm Hg versus 80±9 years and 42±13 mm Hg in the deceased group. The proportions of female patients were similar in both groups (p=0.7). Both CP and GCP were independently associated with survival at 1 year. The area under ROCs for CP, CP1, CP2, and CP3 were 0.67 [95% confidence interval (CI), 0.62-0.72], 0.65 (95% CI, 0.60-0.70), 0.66 (95% CI, 0.61-0.71), and 0.63 (95% CI 0.58-0.68), respectively. CONCLUSION: GCP did not improve the accuracy of predicting survival post TAVR at 1 year, compared to CP alone.


Assuntos
Pressão Arterial/fisiologia , Débito Cardíaco/fisiologia , Substituição da Valva Aórtica Transcateter , Idoso de 80 Anos ou mais , Área Sob a Curva , Feminino , Humanos , Estimativa de Kaplan-Meier , Modelos Logísticos , Masculino , Análise Multivariada , Modelos de Riscos Proporcionais , Curva ROC , Fatores de Risco , Substituição da Valva Aórtica Transcateter/mortalidade , Resultado do Tratamento
15.
Anaesthesia ; 75(10): 1307-1313, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32469423

RESUMO

Maternal cardiac dysfunction is associated with pre-eclampsia, fetal growth restriction and haemodynamic instability during obstetric anaesthesia. There is growing interest in the use of non-invasive cardiac output monitoring to guide antihypertensive and fluid therapies in obstetrics. The aim of this study was to validate thoracic bioreactance using the NICOM® instrument against transthoracic echocardiography in pregnant women, and to assess the effects of maternal characteristics on the absolute difference of stroke volume, cardiac output and heart rate. We performed a prospective study involving women with singleton pregnancies in each trimester. We recruited 56 women who were between 11 and 14 weeks gestation, 57 between 20 and 23 weeks, and 53 between 35 and 37 weeks. Cardiac output was assessed repeatedly and simultaneously over 5 min in the left lateral position with NICOM and echocardiography. The performance of NICOM was assessed by calculating bias, 95% limits of agreement and mean percentage difference relative to echocardiography. Multivariate regression analysis evaluated the effect of maternal characteristics on the absolute difference between echocardiography and NICOM. The mean percentage difference of cardiac output measurements between the two methods was ±17%, with mean bias of -0.13 l.min-1 and limits of agreement of -1.1 to 0.84; stroke volume measurements had a mean percentage difference of ±15%, with a mean bias of -0.8 ml (-10.9 to 12.6); and heart rate measurements had a mean percentage difference of ±6%, with a mean bias of -2.4 beats.min-1 (-6.9 to 2.0). Similar results were found when the analyses were confined to each individual trimester. The absolute difference between NICOM and echocardiography was not affected by maternal age, weight, height, race, systolic or diastolic blood pressure. In conclusion, NICOM demonstrated good agreement with echocardiography, and can be used in pregnancy for the measurement of cardiac function.


Assuntos
Débito Cardíaco/fisiologia , Gravidez/fisiologia , Adulto , Ecocardiografia , Feminino , Idade Gestacional , Frequência Cardíaca , Humanos , Monitorização Fisiológica , Pré-Eclâmpsia , Estudos Prospectivos , Reprodutibilidade dos Testes , Volume Sistólico , Resistência Vascular
16.
PLoS One ; 15(5): e0232830, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32407353

RESUMO

During general anesthesia (GA), direct analysis of arterial pressure or aortic flow waveforms may be inconclusive in complex situations. Patient-specific biomechanical models, based on data obtained during GA and capable to perform fast simulations of cardiac cycles, have the potential to augment hemodynamic monitoring. Such models allow to simulate Pressure-Volume (PV) loops and estimate functional indicators of cardiovascular (CV) system, e.g. ventricular-arterial coupling (Vva), cardiac efficiency (CE) or myocardial contractility, evolving throughout GA. In this prospective observational study, we created patient-specific biomechanical models of heart and vasculature of a reduced geometric complexity for n = 45 patients undergoing GA, while using transthoracic echocardiography and aortic pressure and flow signals acquired in the beginning of GA (baseline condition). If intraoperative hypotension (IOH) appeared, diluted norepinephrine (NOR) was administered and the model readjusted according to the measured aortic pressure and flow signals. Such patients were a posteriori assigned into a so-called hypotensive group. The accuracy of simulated mean aortic pressure (MAP) and stroke volume (SV) at baseline were in accordance with the guidelines for the validation of new devices or reference measurement methods in all patients. After NOR administration in the hypotensive group, the percentage of concordance with 10% exclusion zone between measurement and simulation was >95% for both MAP and SV. The modeling results showed a decreased Vva (0.64±0.37 vs 0.88±0.43; p = 0.039) and an increased CE (0.8±0.1 vs 0.73±0.11; p = 0.042) in hypotensive vs normotensive patients. Furthermore, Vva increased by 92±101%, CE decreased by 13±11% (p < 0.001 for both) and contractility increased by 14±11% (p = 0.002) in the hypotensive group post-NOR administration. In this work we demonstrated the application of fast-running patient-specific biophysical models to estimate PV loops and functional indicators of CV system using clinical data available during GA. The work paves the way for model-augmented hemodynamic monitoring at operating theatres or intensive care units to enhance the information on patient-specific physiology.


Assuntos
Anestesia Geral/métodos , Pressão Arterial/fisiologia , Débito Cardíaco/fisiologia , Monitorização Hemodinâmica/métodos , Hipotensão/fisiopatologia , Modelos Cardiovasculares , Volume Sistólico/fisiologia , Algoritmos , Fenômenos Biomecânicos , Pressão Sanguínea , Feminino , Humanos , Hipotensão/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Norepinefrina/administração & dosagem , Estudo de Prova de Conceito , Estudos Prospectivos , Vasoconstritores/administração & dosagem
17.
Life Sci ; 253: 117732, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32360570

RESUMO

AIMS: Recently, the zebrafish has gained attention as an innovative experimental model to decipher molecular and cellular mechanisms involved in cardiovascular development and diseases. Nevertheless, the use of zebrafish models has been challenged because the transparency of these fish, which allows for accurate cardiac evaluation, disappears in adulthood. In this study, the epicardial outline method was performed to investigate the feasibility of echocardiography in assessing cardiac function in pathological adult zebrafish. MATERIALS AND METHODS: We attempted to estimate heart failure in adult zebrafish treated with three distinct regulators of cardiac function: phenylhydrazine hydrochloride (PHZ), doxorubicin (DOX), and ethanol. B-mode and Doppler images were evaluated at frequencies of up to 50 MHz and 40 MHz, respectively. The correlation between alterations in cardiac function, haemoglobin concentration, and myocardial histopathology were assessed. KEY FINDINGS: Cardiac output (CO) in PHZ-treated zebrafish was significantly higher than that in control zebrafish (151 ± 67 vs. 84 ± 37 µl/min, P = 0.004), whereas ejection fraction (EF) was lower (36.3 ± 10.9 vs. 50.9 ± 8.7%, P < 0.001), indicating typical high output heart failure derived from anaemia. Additionally, ventricular dysfunction in DOX-treated zebrafish was characterised by low CO (57 ± 38 µl/min) and EF (28.8 ± 10.4%), accompanied by an enlarged ventricle in diastole and systole, representing low output heart failure. For ethanol-treated zebrafish, EF was markedly reduced (39.6 ± 7.2%) indicating a dilated heart, while CO remained unchanged (90 ± 40 µl/min). SIGNIFICANCE: The epicardial outline method is an effective way of using echocardiography to assess cardiac dysfunction in pathological adult zebrafish, unlocking a major bottleneck in this research field with limited cardiac functional assays.


Assuntos
Ecocardiografia/métodos , Cardiopatias/diagnóstico por imagem , Insuficiência Cardíaca/diagnóstico por imagem , Pericárdio/diagnóstico por imagem , Animais , Débito Cardíaco/fisiologia , Modelos Animais de Doenças , Doxorrubicina/toxicidade , Etanol/toxicidade , Estudos de Viabilidade , Feminino , Cardiopatias/fisiopatologia , Insuficiência Cardíaca/fisiopatologia , Fenil-Hidrazinas/toxicidade , Disfunção Ventricular/diagnóstico por imagem , Disfunção Ventricular/fisiopatologia , Peixe-Zebra
18.
Am J Obstet Gynecol ; 223(4): 578.e1-578.e11, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32343954

RESUMO

BACKGROUND: Ureaplasma parvum infection is a prevalent cause of intrauterine infection associated with preterm birth, preterm premature rupture of membranes, fetal inflammatory response syndrome, and adverse postnatal sequelae. Elucidation of diagnostic and treatment strategies for infection-associated preterm labor may improve perinatal and long-term outcomes for these cases. OBJECTIVE: This study assessed the effect of intraamniotic Ureaplasma infection on fetal hemodynamic and cardiac function and the effect of maternal antibiotic treatment on these outcomes. STUDY DESIGN: Chronically catheterized pregnant rhesus monkeys were assigned to control (n=6), intraamniotic inoculation with Ureaplasma parvum (107 colony-forming units/mL, n=15), and intraamniotic infection plus azithromycin treatment (12.5 mg/kg twice a day intravenously, n=8) groups. At approximately 135 days' gestation (term=165 days), pulsed and color Doppler ultrasonography was used to obtain measurements of fetal hemodynamics (pulsatility index of umbilical artery, ductus venosus, descending aorta, ductus arteriosus, aortic isthmus, right pulmonary artery, middle cerebral artery and cerebroplacental ratio, and left and right ventricular cardiac outputs) and cardiac function (ratio of peak early vs late transmitral flow velocity [marker of ventricular function], Tei index [myocardial performance index]). These indices were stratified by amniotic fluid proinflammatory mediator levels and cardiac histology. RESULTS: Umbilical and fetal pulmonary artery vascular impedances were significantly increased in animals from the intraamniotic inoculation with Ureaplasma parvum group (P<.05). Azithromycin treatment restored values to control levels. Amniotic fluid prostaglandin F2 alpha levels were significantly higher in animals with abnormal umbilical artery pulsatility index (>1.1) than in those with normal blood flow (P<.05; Spearman ρ=0.6, P<.05). In the intraamniotic inoculation with Ureaplasma parvum group, left ventricular cardiac output was significantly decreased (P<.001), and more animals had abnormal right-to-left ventricular cardiac output ratios (defined as >1.6, P<.05). Amniotic fluid interleukin-6 concentrations were elevated in cases of abnormal right-to-left ventricular cardiac output ratios compared with those in normal cases (P<.05). CONCLUSION: Fetal hemodynamic alterations were associated with intraamniotic Ureaplasma infection and ameliorated after maternal antibiotic treatment. Doppler ultrasonographic measurements merit continuing investigation as a diagnostic method to identify fetal cardiovascular and hemodynamic compromise associated with intrauterine infection or inflammation and in the evaluation of therapeutic interventions or clinical management of preterm labor.


Assuntos
Antibacterianos/uso terapêutico , Azitromicina/uso terapêutico , Corioamnionite/tratamento farmacológico , Coração Fetal/fisiopatologia , Hemodinâmica/fisiologia , Complicações Infecciosas na Gravidez/tratamento farmacológico , Infecções por Ureaplasma/tratamento farmacológico , Administração Intravenosa , Âmnio , Líquido Amniótico/imunologia , Animais , Aorta/diagnóstico por imagem , Velocidade do Fluxo Sanguíneo , Débito Cardíaco/fisiologia , Corioamnionite/imunologia , Corioamnionite/fisiopatologia , Modelos Animais de Doenças , Canal Arterial/diagnóstico por imagem , Ecocardiografia Doppler , Feminino , Injeções , Interleucina-6/imunologia , Macaca mulatta , Artéria Cerebral Média/diagnóstico por imagem , Gravidez , Complicações Infecciosas na Gravidez/imunologia , Complicações Infecciosas na Gravidez/fisiopatologia , Artéria Pulmonar/diagnóstico por imagem , Fluxo Pulsátil , Ultrassonografia Doppler , Ultrassonografia Pré-Natal , Artérias Umbilicais/diagnóstico por imagem , Ureaplasma , Infecções por Ureaplasma/imunologia , Infecções por Ureaplasma/fisiopatologia
19.
BJOG ; 127(8): 1018-1025, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32133780

RESUMO

OBJECTIVE: To compare maternal haemodynamics in women at low and high risk for preterm pre-eclampsia (PE), and between those at high risk who are randomised to aspirin or placebo. DESIGN: Prospective, longitudinal observational study. SETTING: Maternity units in six UK hospitals. POPULATION: Women participating in the Aspirin for Prevention of Preterm Pre-eclampsia (ASPRE) trial. The population comprised three groups of women: low risk for preterm PE (n = 1362), high risk for preterm PE treated with aspirin (n = 208) and high risk for preterm PE on placebo (n = 220). METHODS: Women had four visits during pregnancy: 11-14, 19-24, 30-34, and 35-37 weeks' gestation. Blood pressure was measured with a device validated for pregnancy, and PE and maternal haemodynamics were assessed with a bioreactance monitor at each visit. A multilevel linear mixed-effects analysis was performed to examine longitudinal changes of maternal haemodynamic variables, controlling for demographic characteristics, past medical history and medication use. MAIN OUTCOME MEASURES: Longitudinal changes of cardiac output (CO), mean arterial pressure (MAP), and peripheral vascular resistance (PVR). RESULTS: The low-risk group demonstrated the expected changes with an increase in CO and reduction in MAP and PVR, with a quadratic change across gestation. In contrast, the high-risk groups had a declining CO, and higher MAP and PVR during pregnancy. The administration of aspirin did not appear to affect maternal haemodynamics. CONCLUSIONS: Women screened as high risk for preterm PE have a pathological cardiac adaptation to pregnancy and the prophylactic use of aspirin (150 mg oral daily from the first trimester) in this group may not alter this haemodynamic profile. TWEETABLE ABSTRACT: In women at high risk of pre-eclampsia, prophylactic use of aspirin may not alter the impaired maternal cardiac adaptation.


Assuntos
Aspirina/uso terapêutico , Débito Cardíaco/efeitos dos fármacos , Inibidores da Agregação de Plaquetas/uso terapêutico , Pré-Eclâmpsia/prevenção & controle , Gravidez de Alto Risco/efeitos dos fármacos , Adulto , Pressão Arterial/efeitos dos fármacos , Pressão Arterial/fisiologia , Débito Cardíaco/fisiologia , Feminino , Idade Gestacional , Humanos , Estudos Longitudinais , Pré-Eclâmpsia/tratamento farmacológico , Gravidez , Gravidez de Alto Risco/fisiologia , Estudos Prospectivos , Fatores de Risco , Resultado do Tratamento , Resistência Vascular/efeitos dos fármacos , Resistência Vascular/fisiologia
20.
Transplant Proc ; 52(5): 1585-1587, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32217008

RESUMO

INTRODUCTION: The aim of this retrospective study was to evaluate any relationship between cardiac power index (CPI) and preload indexes during liver transplantation (LT). METHODS: Thirty-three patients with normal preoperative cardiac evaluation undergoing LT were included. Anesthesia management was standardized. Monitoring included continuous cardiac output determination by pulmonary artery catheter. CPI was calculated throughout LT by using the following standard formula: Mean Arterial Pressure [mm Hg] × Cardiac Index [L/min/m2] × k, where k = 0.0022. A logistic regression to determine which preload indexes predicted an adequate CPI (≥ 0.4 watt/m2) was performed. Postregression analysis was carried out to calculate a cutoff of right ventricle end diastolic volume index (RVEDVI) able to guarantee an adequate CPI after establishing a sensitivity >0.9. The area under receiver operating characteristic curve (AUC) was also run separately for patients with a Model for End-Stage Liver Disease (MELD) score < or ≥ 25 to establish an accurate level of prediction in these subgroups (post-hoc analysis). RESULTS: Logistic regression showed that RVEDVI was the only predictor of CPI (AUC = 0.81). A cutoff value for RVEDVI of 105 mL/m2 was found (sensitivity = 90.5%; specificity = 50%). RVEDVI predicted CPI with moderate accuracy (AUC = 0.80) in patients with MELD < 25 (n = 25), whereas the prediction was highly accurate (AUC = 0.96) in patients with MELD ≥ 25 (n = 8). CONCLUSION: An RVEDVI = 105 mL/m2 can be considered a valid cutoff to perform a fluid challenge to optimize preload during LT. Sicker recipients (with MELD ≥ 25) could exhibit less tolerance to preload reduction, proven by a decrease of CPI below the minimum value considered safe (0.40 watt/m2).


Assuntos
Débito Cardíaco/fisiologia , Doença Hepática Terminal/fisiopatologia , Doença Hepática Terminal/cirurgia , Transplante de Fígado , Adulto , Idoso , Cateterismo de Swan-Ganz , Feminino , Hemodinâmica , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Monitorização Fisiológica , Valor Preditivo dos Testes , Curva ROC , Estudos Retrospectivos
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