Comparing cardiac CT angiography and MR angiography in evaluating left ventricular function and volumes / Comparación de la angiografía por TC y la angiografía por RM para evaluar la función y los volúmenes del ventrículo izquierdo

Abstract Background: cardiovascular diseases are among the principal causes of mortality and morbidity worldwide. Prevention, early diagnosis and treatment can play an important role in reducing complication of cardiovascular diseases. Objectives: Considering increasing popularity of cardiac computed tomography CT angiography (CTA) in one side and also magnetic esonance angiography (MRA) as gold standard modality on the other side, we decided to perform this meta-analysis study to compare cardiac CTA and MRA in evaluating left ventricular volumes. Method: this study is a systematic review in which we included all studies with inclusion criteria and without exclusion criteria up to 30 December, 2019. Studies were selected after searching on different databases and articles in bibliography of included studies. Obtained studies were screened for quality. Required data were extracted and were then analyzed via STATA 11 statistical package. Results: among 90 articles obtained in primary search, finally 19 studies entered data extraction and synthesis. Based on our meta-analysis, standardized mean difference was -0.09 (95% CI -0.2, 0.02) for end systolic volume (ESV), -0.10 (95% CI -0.22, 0.01) for end diastolic volume (EDV), 0.10 (95% CI -0.01, 0.22) for ejection fraction (EF) and -0.09 (95% CI -0.23, 0.04) for stroke volume (SV). Conclusion: Results of this systematic review and meta-analysis showed that there is no statistically significant difference between CTA and MRA in evaluating ESV, EDV, EF and SV. Based on our findings, it can be interpreted that CTA has similar accuracy with MRA in evaluating ventricular volumes.

Resumen Introducción: Las enfermedades cardiovasculares están entre las principales causas de morbimortalidad global. La prevención, el diagnóstico precoz y el tratamiento pueden desempeñar un papel importante en la reducción de las complicaciones de las enfermedades cardiovasculares. Objetivo: Teniendo en cuenta la creciente popularidad de la angiografía por tomografía computarizada (ATC) cardiaca, por un lado, y también la angiografía por resonancia magnética (ARM) como el método de referencia, por el otro, decidimos llevar a cabo un metaanálisis para comparar la ATC y la ARM cardiaca en la evaluación de los volúmenes del ventrículo izquierdo. Método: Revisión sistemática en la cual incluimos todos los estudios con criterios de inclusión y sin criterios de exclusión hasta el 30 de diciembre de 2019. Los estudios se seleccionaron de diferentes bases de datos y artículos de las bibliografías de los estudios incluidos. Los estudios obtenidos se examinaron para evaluar su calidad. Los datos requeridos fueron extraídos y luego analizados utilizando el paquete estadístico STATA 11. Resultados: De los 90 artículos obtenidos en la búsqueda primaria, finalmente 19 estudios entraron a extracción de datos y síntesis. Según nuestro metaanálisis, la diferencia de medias estandarizada fue de −0.09 (intervalo de confianza del 95% [IC95%] −0.2 a 0.02) para el volumen sistólico final (VSF), −0.10 (IC95%: −0.22 a 0.01) para el volumen diastólico final (VDF), 0.10 (IC95%: −0.01 a 0.22) para la fracción de eyección (FE) y − 0.09 (IC95%: −0.23 a 0.04) para el volumen sistólico (VS). Conclusiones: Los resultados de esta revisión sistemática y metaanálisis mostraron que no existe una diferencia estadísticamente significativa entre la ATC y la ARM en la evaluación del VSF, el VDF, la FE y el VS. Basado en nuestros hallazgos, se puede interpretar que la ATC tiene una precisión parecida a la ARM en la evaluación de los volúmenes ventriculares.

Correlation between Coronary Angiography and Impedance Cardiography

Aims and Objectives: The aims of the study were to find out the correlation between coronary angiographic findings and hemodynamic parameters derived from impedance cardiography (ICG) and echo-Doppler study. Patients, Materials and Methods: A total of 200 patients of acute myocardial infarction having chest pain, ST elevation in two or more contiguous leads of electrocardiogram (ECG), biomarker positivity, echocardiographic evidence of regional wall motion abnormality (RWMA), and coronary angiographic evidence of coronary lesions were recruited. Subjects unwilling to participate, moribund, critically ill subjects, and patients with concomitant heart failure, arrhythmia, and valvular lesions were excluded from the study. GE™ Vivid 7 Dimension machine was used for ECG-gated echo-Doppler studies. The left ventricular ejection fraction (LVEF), stroke volume (SV), RWMA, diastolic function, etc., were observed. ICG measured LVEDV, LVESV, LVEF, and other parameters particularly amplitudes of the different waves. Coronary angiography (CAG) was done in the Cath Lab having “Siemens™ Axiom Artis Zee (floor)” equipment. Results and Analysis: Results-analysis revealed there is negative correlation (Pearson’s correlation coefficient, r = −0.8) between augmentation pressure and coronary angiographic stenosis percentage and P value is also significant (P = 0.034). Pulse pressure (PP) also is positively correlated (r = −0.78) with coronary angiographic stenosis percentage and P value is also significant (P = 0.027). There is a negative correlation (r = −0.259) between augmentation index (AIx) and coronary angiographic lesions and that is statistically significant (P = 0.03). Conclusion: There is a positive correlation between ICG -derived hemodynamic parameters and the percentage stenosis of coronary arteries. Rise of augmentation pressure and PP in the ICG waveform is associated with coronary artery disease severity. AIx is negatively correlated with severity of coronary arterial stenosis

Synergistic Effect of Disease Severity, Anxiety Symptoms and Elderly Age on the Quality of Life of Outpatients with Heart Failure / Efeito Sinérgico da Gravidade da Doença, de Sintomas de Ansiedade e da Idade Avançada sobre a Qualidade de Vida de Pacientes Ambulatoriais com Insuficiência Cardíaca

Abstract Background: Heart failure (HF) is a multifactorial syndrome with repercussions on quality of life (QoL). Objectives: To investigate the main interacting factors responsible to worsen quality of life of outpatients with HF. Methods: Cross-sectional observational study with 99 patients of both genders, attending a HF outpatient clinic at a university hospital, all with a reduced ejection fraction (<40%) by echocardiography. They were evaluated using sociodemographic and clinical questionnaires, the Minnesota Living with Heart Failure (MLwHF), and the Hospital Anxiety and Depression scale (HADS). QoL was the outcome variable. Two multivariate models were used: the parametric beta regression analysis, and the non-parametric regression tree, considering p < 0.05 and 0.05 < p < 0.10 for statistical and clinical significance, respectively. Results: Beta regression showed that depression and anxiety symptoms worsened the QoL of HF patients, as well as male sex, age younger than 60 years old, lower education level, lower monthly family income, recurrent hospitalizations and comorbidities such as ischemic heart diseases and arterial hypertension. The regression tree confirmed that NYHA functional class III and IV worsen all dimensions of MLwHF by interacting with anxiety symptoms, which influenced directly or indirectly the presence of poorer total score and emotional dimension of MLwHF. Previous hospitalization in the emotional dimension and age younger than 60 years in general dimension were associated with anxiety and NYHA functional class, also worsening the QoL of HF patients. Conclusion: HF with reduced ejection fraction was associated with poorer MLwHF. Anxiety symptoms, previous hospitalization and younger age were also associated with worsened MLwHF. Knowledge of these risk factors can therefore guide assessment and treatment of HF patients.

Resumo Fundamento: A insuficiência cardíaca (IC) é uma síndrome multifatorial com repercussões sobre a qualidade de vida (QV). Objetivo: Investigar os principais fatores que interagem e pioram a qualidade de vida de pacientes ambulatoriais com IC. Métodos: Estudo transversal observacional com 99 pacientes, de ambos os sexos, atendidos no ambulatório de IC de um hospital universitário, todos com uma fração de ejeção reduzida (<40%) pela ecocardiografia. Os participantes foram avaliados usando-se um questionário sociodemográfico, um questionário clínico, o Minnesota Living with Heart Failure (MLwHF), e Hospital Anxiety and Depression scale (HADS). QV foi a variável de desfecho. Foram usados dois modelos de análise multivariada, a regressão beta (paramétrica) e a árvore de regressão (não paramétrica), considerando um p < 0,05 e 0,05 < p < 0,10 para significância estatística e clínica, respectivamente. Resultados: A análise por regressão beta mostrou que os sintomas de depressão e ansiedade pioraram a QV de pacientes com IC, bem como o sexo masculino, idade inferior a 60 anos, nível educacional mais baixo, renda familiar mensal menor, internações recorrentes e comorbidades tais como doenças cardíacas isquêmicas e hipertensão arterial. A árvore de regressão confirmou que as classes funcionais da NYHA III e IV pioraram todas as dimensões do MLwHF, interagindo com sintomas de ansiedade, e influenciando direta ou indiretamente, a presença de pior escore total e dimensão emocional do MLwHF. Internações anteriores, na dimensão emocional, e idade inferior a 60 anos, na dimensão geral, associaram-se com ansiedade e classe funcional NYHA, piorando também a QV dos pacientes com IC. Conclusão: IC com fração de ejeção reduzida associou-se com pior resultado do MLwHF. Sintomas de ansiedade, internação prévia e idade mais jovem também associaram-se com pior MLwHF. O conhecimento desses fatores de risco pode, portanto, orientar a avaliação e o tratamento dos pacientes com IC.

Comparación del gasto cardiaco medido a través del volumen sistólico en modo bidimensional versus ecuación de continuidad en pacientes de terapia intensiva del Hospital General «Las Américas¼ / Comparison of cardiac output measured through the systolic volume in two-dimensional mode versus continuity equation in intensive care patients of the General Hospital «Las Américas¼ / Comparação do dédito cardíaco medido através do volume sistólico em modo bidimensional versus equação contínua em pacientes de terapia intensiva do Hospital Geral «Las Américas¼

Resumen: La ecocardiografía realizada por especialistas no radiólogos es una herramienta que contribuye al diagnóstico y monitoreo de los pacientes críticos, además de ser una herramienta económica, precisa, no invasiva y que se puede realizar a la cabecera del paciente. La medida del gasto cardiaco se refiere a la cantidad de sangre que sale de los ventrículos del corazón a la circulación mayor o menor; en el ámbito de la medicina crítica, es una medida muy importante para verificar el diagnóstico etiológico del estado de choque y además se utiliza para guiar el manejo de los pacientes. Nuestro estudio comparó la medida de gasto cardiaco medido a través del volumen sistólico en modo bidimensional versus ecuación de continuidad.

Abstract: The echocardiography performed by non-radiological specialists is a tool that contributes to the diagnosis and monitoring of critical patients, as well as being an inexpensive, accurate, non-invasive tool that can be performed at the patient's bedside. The measurement of cardiac output refers to the amount of blood sold from the ventricles of the heart to the major or minor circulation in the field of critical medicine is a very important measure to verify the diagnosis and the state of the shock syndrome and if it is used to guide the management of patients, our study compared the measurement of cardiac output through systolic volume in two-dimensional mode versus the continuity equation.

Resumo: O ecocardiograma realizado por não radiologistas é uma ferramenta que contribui para o diagnóstico e acompanhamento de pacientes críticos, além de ser uma ferramenta não invasiva, de baixo custo e que pode ser realizada à beira do leito. A medida do débito cardíaco refere-se à quantidade de sangue que sai dos ventrículos cardíacos até a maior ou menor circulação. No campo da medicina crítica é uma medida muito importante para verificar o diagnóstico etiológico do estado de choque e também é utilizada para orientar o manejo dos pacientes. Nosso estudo comparou a medida do débito cardíaco medida através do volume sistólico no modo bidimensional versus a equação de continuidade.

Real-time three-dimensional echocardiographic left heart parameters in healthy indian adults

Objective Cardiac chamber dimensions are race and anthropometry dependent. We determined the age and gender specific 3-Dimensional echocardiographic (3DE) reference values for dimensions and function of left ventricle (LV) and left atrium (LA) in normal Indian adults. Methods This single center prospective study enrolled 133 adult Indians free of heart disease and/or hypertensions, subjecting them to 3DE measurements of left atrial (LA) & left ventricular (LV) volumes, function and left ventricular mass (LVM). The higher limits of normal cut-offs were determined for these parameters and their dependency on age, gender and anthropometry were analyzed. Results The body surface area (BSA) corrected higher limit cut-offs were: 59.37 ml/m2 for LV end diastolic volume (59.19 ml/m2 and 59.61 ml/m2 for men and women, respectively; P = NS); 23.48 ml/m2 for LV end systolic volume (23.27 ml/m2 and 23.11 ml/m2 for men and women, P = NS). Mean LVEF was 64.79% ± 7.26 (62.99% ± 6.51 and 67.05% ± 7.58 in men and women, P = NS). Men had higher LVM than women (119.79 g±23.95 vs. 103.26 g±23.76, P < 0.001), this difference disappeared after BSA indexing. The higher limit cut-offs for normal LA volumes were 20.49 ml for minimum volume (21.18 ml and 19.46 ml for men and women, P = NS) and 39.76 ml for maximum volume (39.60 ml and 40.03 ml in men and women, P = NS). The parameters were smaller compared to western populations but the differences attenuated after BSA indexing. Conclusions The study reports normal 3DE parameters of size and function of left heart chambers in Indians.

Comportamiento en la hemodinamia en pacientes con hemorragia controlada por monitor ultrasónico (USCOM) / Behavior in hemodynamics in patients with ultrasonic monitor controlled hemorrhage (USCOM) / Comportamento da hemodinâmica em pacientes com hemorragia controlada pelo monitor ultrasônico (USCOM)

Resumen: Introducción: La hemodinamia es la parte de la biofísica que se encarga del estudio anatómico y funcional del corazón, de la dinámica de la sangre en el interior de las estructuras sanguíneas, así como de la mecánica del corazón. Objetivo: Comparar la hemodinamia con el dispositivo no invasivo USCOM antes y después de presentar hemorragia controlada. Material y métodos: Se realizó un estudio tipo observacional, prospectivo, longitudinal y comparativo en pacientes de entre 16 y 65 años de edad en un periodo de seis meses como fecha corte para este premio académico (marzo de 2016-proyecto aún en curso). Resultados: Se obtuvieron promedios de las diferentes variables hemodinámicas, de precarga, postcarga e inotropismo, observando cambios tempranos a la exanguinación de los pacientes, siendo principalmente las resistencias vasculares sistémicas las que se modifican. Discusión: Existen cambios hemodinámicos tempranos a la exanguinación de pequeñas cantidades de sangre en los pacientes, cambios determinados por el sistema USCOM, sistema fácil de usar, no invasivo y preciso en los resultados ofrecidos. Conclusiones: En este estudio podemos observar cómo las variables relacionadas a la postcarga (resistencias vasculares sistémicas) son las primeras variables que se modifican, por lo que con la pérdida de pequeñas cantidades de sangre llegamos a observar esto.

Abstract: Introduction: Hemodynamics is the part of biophysics that is responsible for the anatomical and functional study of the heart, the dynamics of blood inside the blood structures as well as the mechanics of the heart. Objective: To compare the hemodynamics of our patients with the non-invasive device USCOM, before and after presenting with controlled hemorrhage. Material and methods: An observational, prospective, longitudinal and comparative study was performed in patients between the ages of 16 and 65 in a period of 6 months as a cutoff date for this academic award. (March 2016-ongoing). Results: We obtained averages of the different hemodynamic variables, both preload, afterload and inotropism, observing early changes to the exanguination of the patients, being mainly the systemic vascular resistances that are modified. Discussion: There are early hemodynamic changes to the exanguination of small amounts of blood in the patients, changes determined by the USCOM system, system easy to use, non-invasive and accurate results offered. Conclusions: In this study we can observe how the variables related to afterload (systemic vascular resistance) are the first variables that are modified, so that with the loss of small amounts of blood we get to observe this.

Resumo: Introdução: A hemodinâmica é a parte da biofísica responsável pelo estudo anatômico e funcional do coração, da dinâmica do sangue dentro das estruturas sangüíneas, bem como a mecânica do coração. Objetivo: Comparar a hemodinâmica com o dispositivo USCOM não invasivo, antes e após a apresentação da hemorragia controlada. Material e metodos: Foi realizado um estudo observacional, prospectivo, longitudinal e comparativo em pacientes entre 16 e 65 anos de idade, em um período de 6 meses, como data limite para este prêmio acadêmico (Março de 2016 - projeto ainda em andamento). Resultados: Obtivemos as médias das diferentes variáveis hemodinâmicas, tanto de pré-carga, pós-carga e inotropismo, observando as alterações precoces na exanguinação dos pacientes, sendo principalmente as resistências vasculares sistêmicas aquelas que são modificadas. Discussão: Existem alterações hemodinâmicas precoces na exsanguinação de pequenas quantidades de sangue nos pacientes, mudanças determinadas pelo sistema USCOM fáceis de usar, não invasivas e precisas nos resultados oferecidos. Conclusões: Neste estudo podemos observar como as variáveis relacionadas à pós-carga (resistência vascular sistêmica) são as primeiras variáveis que são modificadas, de modo que com a perda de pequenas quantidades de sangue podemos observar isso.

Effect of obstructive jaundice on accuracy of left ventricular end-diastolic volume and stroke volume variability in monitoring fluid responsiveness / 中华麻醉学杂志

Objective To evaluate the effect of obstructive jaundice on the accuracy of left ventricular end-diastolic volume (LVEDV) and stroke volume variability (SVV) in monitoring fluid responsiveness.Methods Thirty patients of both sexes,aged 45-60 yr,weighing 55-70 kg,of American Society of Anesthesiologists physical status Ⅰ or Ⅱ,with New York Heart Association Ⅰ,scheduled for elective pancreatoduodenectomy,were divided into 2 groups according to the serum total bilirubin levels:A group (serum total bilirubin ≥ 17 μmmol/L,n =16) and B group (serum total bilirubin＜ 17 μmmol/L,n =14).Six percent hydroxyethyl starch 500 ml was infused over 40 min after anesthesia induction.The parameters of VigileoTM such as cardiac output (CO),SVV,systemic vascular resistance (SVR) and pulmonary capillary wedge pressure and indices measured by transesophageal three-dimensional echocardiography such as LVEDV,left ventricular end-systolic volume,CO',left ventricular ejection fraction (LVEF) and ratio of mitral peak velocity of early filling (E) to early diastolic mitral annular velocity (e',E/e'ratio) were recorded before and after fluid loading.Results Compared with that before fluid loading,SVV was significantly decreased in two groups,and CO,LVEDV,CO'and LVEF were significantly increased in group B,and E/e'ratio was significantly increased in group A (P＜0.05).Compared with group B,CO,SVR,CO'and LVEF were significantly decreased,and pulmonary capillary wedge pressure was increased in group A (P＜0.05).Conclusion Obstructive jaundice causes decrease in the accuracy of LVEDV in monitoring fluid responsiveness and no effect on SVV.

Caracterización del síndrome coronario agudo en adultos menores de 45 años de una institución especializada en la Habana, Cuba, entre 2013 y 2014 / Characterization of acute coronary syndrome in younger than 45 years old of one specialist institution in Habana, Cuba between 2013 and 2014

INTRODUCCIÓN: El síndrome coronario agudo en adultos menores de 45 años constituye una condición clínica con características específicas, que lo diferencian de los pacientes mayores, porque predomina una escasa o nula sintomatología previa a la aparición de la patología y además como factores de riesgo tiene las alteraciones del tejido conectivo, los estados de hipercoagulabilidad y el consumo de drogas, que conducen a una baja mortalidad y un pronóstico más favorable. OBJETIVO: Caracterizar el síndrome coronario agudo en adultos jóvenes que ingresaron al Instituto de Cardiología y Cirugía Cardiovascular entre los años 2013 y 2014. MATERIALES Y MÉTODOS: Se trata de un estudio descriptivo y transversal, en el cual se realizó una revisión sistemática de 99 historias clínicas de menores de 45 años con síndrome coronario agudo. Se analizaron variables clínicas, estrategias diagnósticas y terapéuticas. RESULTADOS: La edad promedio fue de 42 años y predominó el sexo masculino. El tabaquismo, la hipertensión y la dislipidemia fueron los factores de riesgo más frecuentes. El dolor típico se presentó en el 70,7 % de los pacientes. Las alteraciones electrocardiográficas de la región inferior (33,3 %), y anterior (22,2 %), fueron las más comunes. La fracción de eyección del ventrículo izquierdo normal (22,2 %), predominó en la enfermedad de un solo vaso. La hipocinesia (48,5 %) y la acinesia (26,3 %) predominaron en este síndrome. Las arterias más implicadas fueron la descendente anterior (40,4 %) y la coronaria derecha (28,3 %). El intervencionismo coronario percutáneo primario fue el más realizado en el síndrome coronario agudo con elevación del segmento ST. CONCLUSIONES: La poca extensión de la enfermedad coronaria justificó la conservación de la función ventricular, la hipocinesia segmentaria y el bajo porcentaje de complicaciones. La Intervención coronaria percutánea constituyó la estrategia de reperfusión más utilizada en el síndrome coronario agudo con elevación del segmento ST

INTRODUCTION: Acute coronary syndrome in youngers than 45 years old constitutes a clinical condition with specific characteristics that tells it apart from older patients because the poor symptomatology previous to the origin of the acute coronary syndrome and the presence of peculiars risk factors such as connective tissue disorders, hypercoagulability states and the drugs intake, leads to lesser complications and better prognosis. Objective: characterize the acute coronary syndrome in young adults admitted at the Cardiology and Surgery Cardiovascular's Institute between the years 2013 and 2014. MATERIALS AND METHODS: Descriptive and transverse study with 99 patients under 45 years old who had acute coronary syndrome. There were analyzed clinical variables, diagnostic and therapeutic strategies. RESULTS: The mean age was 42 years and the masculine sex was predominant. Smoking, arterial hypertension and dyslipidemia were the risk factors more common. The typical pain was in the 70.7% of patients. Electrocardiographic disorders of the inferior region (33.3%) and previous (22.2%) were the more frequents. The normal ejection fraction of the left ventricle (22.2%) predominated in the one vessel disease. The hypokinesia (48.5%) and akinesia (26.3%) predominated in this syndrome. The most responsible arteries were the descending previous (40.4%) and the right coronary (28.3%). The coronary percutaneous intervention was the procedure more made in acute coronary syndrome with ST segment elevation. CONCLUSIONS: The minimum extension of the coronary disease justified the conservation of the ventricular function, the segmentary hypokinesia and the softly percent of complications. The coronary percutaneous intervention constituted the strategy of re-perfusion more used in the acute coronary syndrome with elevation of the segment ST

Monitoreo hemodinámico utilizando variabilidad del volumen sistólico como parámetro para guiar el manejo de líquidos en pacientes sépticos

Se presenta una serie de casos donde se compara la variabilidad del volumen sistólico con las variables estáticas habituales en la reanimación con fluidos de pacientes sépticos.

We report a case series where the variability of the systolic volume is compared to the usual static variables of the fluid resuscitation of septic patients.

Efecto del tono vasomotor sobre los índices dinámicos de precarga.: Impacto en la optimización de la reposición con fluidos

Introducción: el uso de vasoconstrictores puede afectar la capacidad de predecir la respuesta a volumen de los índices dinámicos. Objetivo: analizar los efectos del tono vasomotor aumentado sobre los índices dinámicos en un modelo de hemorragia. Métodos: se estudiaron 12 conejos durante normovolemia, luego de extracción de 20% de la volemia (HEM), durante la infusión de fenilefrina (FEN) y luego de la reposición con hidroxietilalmidón (HEA). Se midieron la presión (PAo) y flujo de la aorta (FAo) infradiafragmática, las presiones venosa central y ventricular izquierda, permitiendo estimar la variación de la presión arterial de pulso (VPP), del volumen sistólico (VVS) y la presión diastólica final del ventrículo izquierdo (PDFVI). Se monitorizó la pulsioximetría obteniendo la variación de la onda de pulso oximétrica (VOP) y la variación del índice pletismográfico (VIP). El tono vasomotor fue estimado mediante la resistencia vascular total (RVT=PAo/FAo) y la complacencia (C=SV/PAo pulso). Resultados: durante HEM todos los índices dinámicos aumentaron (p<0,05). La FEN determinó un descenso del FAo (p<0,05) y un aumento del tono vasomotor (p<0,05), seudonormalizando los índices dinámicos. El HEA normalizó el FAo y los índices dinámicos. La PDFVI no se modificó. Hubo correlación significativa entre la VVS y la VPP, VOP y la VIP durante N, HEM y HEA (sin fenilefrina), no habiendo correlación durante la infusión de fenilefrina. Conclusiones: la fenilefrina redujo los índices dinámicos enmascarando la pérdida de volumen posiblemente por el aumento del tono vasomotor. Este debería considerarse durante la optimización de la reposición con fluidos.

Introduction: the use of de vasoconstrictors may affect the ability to predict fluid responsiveness of dynamic indicators. Objective: to analyze the effects of an increased vasomotor tone on dynamic indicators in a model of hemorrhage. Methods: twelve rabbits were studied during normovolemia, after withdrawal of 20% of blood volume (HEM), during phenylephrine infusion (PHE) and after replacement with hydroxyethyl starch (HES). Measurements of blood pressure and flow of infradiaphragmatic aorta (AoP - AoF), central venous (CVP) and left ventricular (LVP) were performed, thus allowing to estimate the variation of pulse arterial pressure (PAP), of sistolic volumen (SVV) and end-distolic pressure of the left ventricle (LVEDP). Pulse oximetry was monitored to obtain the pulse oximetry wave variation (POV) and the plethysmographic variability index (PVI). Vasomotor tone was estimated by calculating the total vascular resistance (TVR=AoP/AoF) and compliance (C=SV/AoP pulse). Results: during HEM there was an increase in all dynamic indicators (p<0.05). PHE determined a decrease in the AoF (p<0.05) and an increase in the vasomotor tone (p<0.05), resulting in a pseudonormalization of the dynamic indicators. The HES normalized the AoF and the dynamic indicators. LVEDP was not modified. There was a significant correlation between the SVV and the PAP, POV and the PVI during N, HEM and HES (without phenylephrine); there was no correlation during phenylephrine infusion. Conclusions: phenylephrine reduced the dynamic indicators and concealed the volume deficit probably due to an increase of vasomotor tone. This should be taken into account during optimization of fluid replacement.

Introdução: o uso de vasoconstritores pode afetar a capacidade de predizer a resposta a volume dos índices dinâmicos. Objetivo: analisar os efeitos do tônus vasomotor aumentado sobre os índices dinâmicos em um modelo de hemorragia. Métodos: estudaram-se 12 coelhos durante normovolemia, após a extração de 20% da volemia (HEM), durante a infusão de fenilefrina (FEN) e logo após a reposição com hidroxietilalmidon (HEA). Mediram-se a pressão (PAo) e o fluxo da aorta (FAo) infradiafragmatica, as pressões venosa central e ventricular esquerda (VI), permitindo estimar a variação da pressão arterial do pulso (VPP), do volume sistólico (VVS) e a pressão diastólica final do VI (PDFVI). Monitorizou-se a oximetria de pulso obtendo a variação da onda de pulso oximetrica (VOP) e a variação do índice pletismografico (VIP). O tônus vasomotor foi estimado mediante a resistência vascular total (RTV=PAo/FAo) e a complacência (C=SV/PAo pulso). Resultados: durante HEM todos os índices dinâmicos aumentaram (p<0.05). A FEN determinou um descenso do FAo (p<0.05) e um aumento do tônus vasomotor (p<0.05), pseudonormalizando os índices dinâmicos. O HEA normalizou o FAo e os índices dinâmicos. O HEA normalizou o FAo e os índices dinâmicos. A PDFVI não se modificou. Houve correlação significativa entre VVS e a VPP,VOP e a VIP durante N, HEM e HEA (sem fenilefrina), não havendo correlação durante a infusão de fenilefrina. Conclusões: a fenilefrina diminui os índices dinâmicos mascarando a perda do volume possivelmente pelo aumento do tônus vasomotor. Este deveria considerar- se durante a otimização da reposição com fluidos.