Cardiac output and the pharmacology of general anesthetics: a narrative review

The relationship between cardiac output and anesthetic drugs is important to anesthesiologists, since cardiac output determines the speed with which a drug infused into the bloodstream reaches its target and the intensity of the drug's effect. But rather than focus on how anesthetic drugs affect cardiac output, this narrative review focuses on how changes in cardiac output affect the pharmacokinetics and pharmacodynamics of general anesthetics during the three phases of anesthesia. At induction, an increase in cardiac output shortens both the onset time of propofol for hypnosis and the neuromuscular blocking effect of rapid-acting neuromuscular blockers, favoring the conditions for rapid sequence intubation. During maintenance, changes in cardiac output are followed by opposite changes in the drug plasma concentration of anesthetic drugs. Thus, an increase in cardiac output followed by a decrease in the plasma concentration of the anesthetic could expose the patient to a real risk of intraoperative awakening, which can be avoided by increasing the dose of hypnotic drugs. At emergence, an increase in cardiac output secondary to an increase in pC02 allows for a more rapid recovery from anesthesia. The pC02 can be increased by adding CO2 to the respiratory circuit, lowering the ventilatory rate, or placing the patient on partial rebreathing. Finally, the reversal action of sugammadex for rocuronium-induced neuromuscular block can be shortened by increasing the cardiac output.

La relación entre el gasto cardíaco y los fármacos anestésicos es importante para los anestesiólogos puesto que el gasto cardíaco determina la velocidad con la cual un medicamento que se infunde al torrente sanguíneo llega a su diana y la intensidad del efecto del agente. Pero en lugar de concentrarnos en cómo los fármacos anestésicos afectan el gasto cardíaco, esta revisión narrativa se enfoca en cómo los cambios en el gasto cardíaco afectan la farmacocinética y la farmacodinámica de los agentes anestésicos generales durante las tres fases de la anestesia. En el momento de la inducción, un incremento en el gasto cardíaco acorta tanto el tiempo de inicio del efecto del propofol para la hipnosis como el efecto del bloqueo neuromuscular causado por los bloqueadores neuromusculares de acción rápida, favoreciendo las condiciones para la intubación de secuencia rápida. Durante la fase de mantenimiento, los cambios en el gasto cardíaco vienen seguidos de cambios opuestos en la concentración plasmática del medicamento de los agentes anestésicos. Por lo tanto, un aumento del gasto cardíaco, seguido de una reducción en la concentración plasmática del anestésico, podría exponer al paciente a un riesgo real de despertar intraoperatorio, lo cual puede evitarse aumentando la dosis de los fármacos hipnóticos. En la educción, un aumento en el gasto cardíaco secundario al incremento en el pCO2 permite una recuperación más rápida de la anestesia. El pCO2 puede aumentar agregando CO2 al circuito de la respiración, reduciendo la tasa ventilatoria, o colocando al paciente en re-inhalación parcial. Finalmente, la acción de reversión de sugammadex en caso de bloqueo neuromuscular inducido por rocuronio, puede acortarse aumentando el gasto cardíaco.

Supervivencia de pacientes con síndrome de bajo gasto cardiaco en el periodo posoperatorio / Survival of patients with low cardiac output syndrome in the postoperative period i: en

Introducción: La intervención quirúrgica cardiaca es compleja, pero con resultados satisfactorios para el paciente, pues incrementa su supervivencia y calidad de vida. El síndrome de bajo gasto cardiaco en el periodo posoperatorio es una de las entidades que ensombrece el pronóstico y eleva los índices de morbilidad y mortalidad en dichos pacientes. Objetivo: Estimar la supervivencia de los pacientes con síndrome de bajo gasto cardiaco en el periodo posoperatorio según variables clínicas y ecocardiográficas. Métodos: Se realizó una investigación de cohorte de supervivencia en 56 pacientes operados del corazón, diagnosticados con síndrome de bajo gasto cardiaco posoperatorio, quienes fueron atendidos en el Centro de Cardiología y Cirugía Cardiovascular de Santiago de Cuba, desde enero del 2019 hasta noviembre del 2021. Resultados: Predominaron el grupo etario de 65 o más años (60,7 %), la diabetes mellitus (44,6 %) como antecedente patológico personal y los pacientes con fracción de eyección de 45 % o más, quienes presentaron mayor cantidad de decesos (29,8 %). La función del ventrículo derecho afectada se halló en 52,6 % de los fallecidos. El tiempo de circulación extracorpórea de 90 minutos o más primó en 67,9 % de los afectados, de los cuales 42,1 % murieron. Conclusiones: Se observó que la diabetes mellitus, el tiempo de circulación extracorpórea y el sangrado perioperatorio prolongados, así como la función sistólica biventricular se relacionaron con el pronóstico del síndrome de bajo gasto cardiaco en el periodo posoperatorio.

Introduction: Heart surgical intervention is complex, but with satisfactory results for the patient, because it increases his survival and life quality. The low cardiac output syndrome in the postoperative period is one of the entities that darkens the prognosis of this operation and elevates the morbidity and mortality indexes in these patients. Objective: To estimate the survival of patients with low cardiac output syndrome in the postoperative period according to clinical and echocardiographyc variables. Methods: A cohort investigation of survival in 56 operated patients was carried out, who were diagnosed with postoperative low cardiac output syndrome and were assisted in the Cardiology and Cardiovascular Surgery Center of Santiago de Cuba, from January, 2019 to November, 2021. Results: There was prevalence of the 65 years and over age group (60.7%), the diabetes mellitus (44.6%) as personal pathological history and patients with ejection fraction of 45% or more who presented higher quantity of deaths (29.8%). The function of the affected right ventricle was found in 52.6% of deaths. The time of extracorporeal circulation of 90 minutes or more prevailed in 67.9% of those affected, of whom 42.1% died. Conclusions: It was observed that diabetes mellitus, the time of extracorporeal circulation and the long perioperative bleeding, as well as the biventricular systolic function was related to the prognosis of low cardiac output syndrome in the postoperative period.

Central venous-to-arterial CO2 difference as a biomarker of outcome in children who underwent surgery for congenital heart disease / Diferencia arteriovenosa de CO2 como biomarcador de desenlace en niños operados de cardiopatías congénitas

Abstract Background: In congenital heart surgery, low cardiac output syndrome (LCOS) is a major cause of morbidity in the immediate post-operative period. A decrease in cardiac output leads to an increase in tissue oxygen consumption. Several biomarkers such as venous oxygen saturation (SvO2), arteriovenous oxygen difference (DavO2), and lactate can assess tissue perfusion in the presence of LCOS. Recently, central venous to arterial CO2 difference (ΔCO2) has been proposed as a biomarker of tissue ischemia that could be used as a predictor of death in neonatal patients. This study aimed to analyze the relationship between ΔCO2 and immediate post-operative outcomes in pediatric patients undergoing congenital heart surgery and its correlation with DavO2, SvO2, and lactate. Methods: We conducted a longitudinal study of patients aged 0-18 years who underwent congenital heart surgery with or without cardiopulmonary bypass at the Instituto Nacional de Pediatría, from March 2019 to March 2021. Results: Eighty-two patients were included; the median age was 17 months. About 59% had a ΔCO2 ≥ 6 mmHg. Patients with ΔCO2 ≥ 6 mmHg had a vasoactive-inotropic score > 5 (p < 0.001), DavO2 > 5 mL/dL (p = 0.048), and lactate > 2 mmol/L (p = 0.027), as well as a longer hospital stay (p = 0.043). Patients with ΔCO2 > 6 mmHg and vasoactive-inotropic score ≥ 10 were 12.6 times more likely to die. Conclusion: ΔCO2 is a good marker of tissue hypoperfusion and outcome in the post-operative period of congenital heart surgery.

Resumen Introducción: En la cirugía cardiaca de malformaciones congénitas, el síndrome de bajo gasto cardiaco (SBGC) es una de las principales causas de morbilidad en el postoperatorio inmediato. La caída del gasto cardiaco aumenta el consumo de oxígeno en los tejidos. Varios biomarcadores, como la saturación venosa de oxígeno (SvO2), la diferencia arteriovenosa de oxígeno (DavO2) y el lactato han sido utilizados como indicadores hipoperfusión tisular en presencia de SBGC. Recientemente, la diferencia arteriovenosa de CO2 (ΔCO2) se ha propuesto como otro biomarcador de isquemia tisular que podría utilizarse como predictor de muerte en pacientes en edad neonatal. El objetivo de este estudio fue analizar la relación entre la ΔCO2 y la evolución postoperatoria de pacientes pediátricos operados de cardiopatías congénitas y correlacionarlo con la DavO2, SvO2 y lactato. Métodos: Se realizó un estudio longitudinal en pacientes de 0 a 18 años operados de corazón con empleo de bomba de circulación extracorpórea en el Instituto Nacional de Pediatría. Resultados: Se incluyeron 82 pacientes; la mediana de edad fue de 17 meses. El 59% presentó un ΔCO2 > 6 mmHg. Los pacientes con un ΔCO2 > 6 mmHg mostraron un puntaje de inotrópicos > 5 (p < 0.001), DavO2 > 5 mL/dL (p = 0.048) y lactato > 2 mmol/L (p = 0.027), así como mayor estancia hospitalaria (p = 0.043). Los pacientes con ΔCO2 > 6 mmHg y un puntaje de inotrópicos ≥ 10 presentaron una probabilidad de muerte 12.6 veces mayor. Conclusiones: El ΔCO2 en el periodo postoperatorio de una cirugía cardiaca congénita es un buen marcador de hipoperfusión tisular y de desenlace.

Correlation of Venous to Arterial Carbon Dioxide Partial Pressure Difference with other Cardiac Output Indices in Patients Undergoing Intracardiac Repair for Tetralogy of Fallot

Background: Clearance of tissue carbon dioxide by circulation is measured by venous to arterial carbon dioxide partial pressure difference (AVCO2 ) and is correlated with cardiac output (CO) in critically ill adult patients. This study aimed to correlate AVCO2 with other CO indices like arteriovenous oxygen saturation difference (AVO2 ), central venous oxygen saturation (ScVO2 ), and serum lactate in pediatric patients undergoing intracardiac repair (ICR) for tetralogy of Fallot (TOF). Methods: We conducted a prospective observational study in 50 patients, of age 5months to 5 years, undergoing ICR for TOF and analyzed AVO2 , AVCO2 , ScVO2 , and lactate from arterial and venous blood gas pairs obtained at different time intervals from admission to pediatric intensive care unit(PICU)(T0 ), at 6 h (T1 ), 12 h (T2 ), 24 h (T3 ), and 48 h (T4 ) postoperatively. Bivariate correlations were analyzed using Pearson for parametric variables. Results: Admission AVCO2 was not correlated with AVO2 (R2 = 0.166, P = 0.246), ScVO2 (R2 = ?2.2, P = 0.124), and lactate (R2 = ?0.07, P = 0.624). At T1 , AVCO2 was correlated with AVO2 (R2 = 0.283, P = 0.0464) but not with ScVO2 (R2 = ? 0.25, P = 0.079) and lactate (R2 = ?0.07, P = 0.623). At T2 , T3 and T4 , AVCO2 was correlated with AVO2 (R2 = 0.338,0.440 & 0.318, P = 0.0162, 0.0013, and 0.024), ScVO2 (R2 = ? 0.344, ? 0.488, and ?0.366; P = 0.0143, <0.0001, and 0.017), and lactate (R2 = 0.305, 0.467 and 0.607; P = 0.0314, 0.00062 and <0.0001). AVCO2 was negatively correlated with ScVO2 . No correlation observed between admission AVCO2 and mechanical ventilation duration. Two nonsurvivors had higher value of admission AVCO2 compared to survivors. Conclusion: AVCO2 is correlated with other CO surrogates like AVO2 , ScVO2 , and lactate in pediatric patients undergoing ICR for TOF.

Comparision of Cardiac Output Measured by Transthoracic Echocardiography with Continuous Cardiac Output Measured by Pressure Recording Analytical Method

Background: Low cardiac output is a common complication following cardiac surgery and it is associated with higher mortality in the pediatric population. A gold standard method for cardiac output (CO) monitoring in the pediatric population is lacking. The present study was conducted to validate cardiac output and cardiac index measured by transthoracic echocardiography and Pressure recording analytical method, a continuous pulse contour method, MostCare Up in postoperative pediatric cardiac surgical patients. Materials and Methods: This was a prospective observational clinical study conducted at a tertiary care hospital. A total of 23 pediatric patients weighed between 2 and 20 kg who had undergone elective cardiac surgery were included in the study. Results: Spearman抯 correlation coefficient of CO between transthoracic echocardiography (TTE) and Pressure Recording Analytical Method (PRAM) showed of positive correlation (r = 0.69, 95% Confidence interval 0.59?0.77, P < 0.0001) Linear regression equations for CO between TTE and PRAM were y = 0.55 + 0.88x (R2 = 0.46, P < 0.0001). (y = PRAM, x = TTE), respectively. Bland? Altman plot for CO between TTE and PRAM showed a bias of ?0.397 with limits of the agreement being ?2.01 to 1.22. Polar plot analysis showed an angular bias of 6.55� with radial limits of the agreement being ?21.46 to 34.58 for CO and angular bias of 6.22� with radial limits of the agreement being ?22.4 to 34.84 for CI. Conclusion: PRAM has shown good trending ability for cardiac output. However, values measured by PRAM are not interchangeable with the values measured by transthoracic echocardiography.

Cardiopulmonary effects of prolonged surgical abdominal retractors application during general anesthesia: a prospective observational comparative study

Abstract Introduction: Increasing abdominal pressures could affect pulmonary compliance and cardiac performance, a fact based on which the aim of the present study to detect the cardiopulmonary burden of multiple retractors application during supine versus lateral abdominal surgeries. We hypothesized that surgical ring multiple retractors application would affect the pulmonary and cardiac functions during both lateral and supine abdominal surgeries. Methods: Prospective observational comparative study on forty surgical patients subdivided into two groups twenty each, comparing pulmonary compliance and cardiac performance before, during and after retractors application, group (S) supine position cystectomy surgery, and group (L) lateral position nephrectomy surgery under general anesthesia, Composite 1ry outcome; dynamic compliance C-dyn and cardiac index CI and Other outcome variables ICON cardio-meter were also recorded. Results: C-dyn and C-stat were significantly decreased late during retractor application in lateral compared to supine surgery with significant decrease compared to basal values all over the surgical time. CI was significantly increased after retractor removal in both of the study groups compared to basal values. PAW P was significantly increased in -lateral compared to supine surgery -with significant increase compared to basal value all over the surgical time in both of the study groups. significant increase in DO2I compared to basal value during both supine and lateral positions. Conclusion: Surgical retraction results in a short-lived significant decreases in lung compliance and cardiac output particularly during the lateral-kidney position than the supine position compliance.

Predictores clínicos y ecocardiográficos del síndrome de bajo gasto cardiaco en la cirugía valvular cardiaca

Objetivo: Determinar los posibles elementos predictores clínicos y ecocardiográficos asociados a la aparición del síndrome de bajo gasto cardiaco. Materiales y métodos: Se realizó un estudio analítico de casos y controles en pacientes con síndrome de bajo gasto cardiaco posoperatorio atendidos en el Centro de Cardiología y Cirugía Cardiovascular del Hospital Provincial Docente Saturnino Lora de Santiago de Cuba, desde enero 2019 a diciembre 2021. Ambos grupos de estudio formaron parte de la misma población de pacientes operados de cirugía cardiovascular, diferenciados por presentar o no síndrome de bajo gasto cardiaco postoperatorio al ingreso. La variable dependiente fue la presencia de bajo gasto cardiaco; las variables independientes, factores clínicos, hemodinámicos y ecocardiográficos. Resultados: En la serie predominaron los pacientes menores de 65 años tanto en el grupo de casos como de controles (51,2 % y 73,5 %, respectivamente). La fibrilación auricular, la función sistólica del ventrículo derecho y la hemorragia periprocedimiento (p = 0,008) presentaron alta significación estadística p 50 % (102 [91,10 %; p = 0,047]), así como amplio dominio de pacientes (76 [45,24 %; p ≤ 0,05; OR: 2,14]) con cirugías de emergencia. Se realizó una regresión logística, y se determinó que las variables clínicas y ecocardiográficas tales como la edad superior a 65 años, la función de ventrículo derecho deprimida, la circulación extracorpórea ≥90 minutos y la presión sistólica de arteria pulmonar elevada tuvieron una asociación estadísticamente significativa. El AUC mostró que variables como la edad, el tiempo de circulación extracorpórea y la hemorragia perioperatoria tuvieron capacidad predictiva. Conclusiones: Se observó que algunos elementos clínicos y ecocardiográficos, como la edad, la presencia de fibrilación auricular, la función sistólica del ventrículo derecho deprimida y la cirugía de emergencia, se asociaron como predictores de síndrome de bajo gasto cardíaco.

Objective: To determine the possible clinical and echocardiographic predictors associated with the onset of low cardiac output syndrome. Materials and methods: An analytical case-control study was conducted in patients with postoperative low cardiac output syndrome treated at Centro de Cardiología y Cirugía Cardiovascular of Hospital Provincial Docente Saturnino Lora in Santiago de Cuba from January 2019 to December 2021. Both study groups were part of the same population of patients who underwent a cardiovascular surgery but differed in the fact that, at admission, some suffered from postoperative low cardiac output syndrome and others did not. The dependent variable was the presence of low cardiac output and the independent variables were clinical, hemodynamic and echocardiographic factors. Results: In the series, patients under 65 years of age prevailed in both case and control groups (51.2 % and 73.5 %, respectively). Atrial fibrillation, right ventricular systolic function and perioperative bleeding (p = 0.008) were statistically significant (p 50 % and a large number of patients (76 [45.24 %; p ≤ 0.05; OR: 2.14]) had undergone emergency surgeries. A logistic regression analysis determined that the clinical and echocardiographic variables, such as age over 65 years, depressed right ventricular function, extracorporeal circulation ≥ 90 minutes and elevated pulmonary artery systolic pressure, had a statistically significant association. The area under the curve (AUC) showed that variables including age, extracorporeal circulation time and perioperative bleeding had predictive capability. Conclusions: It was observed that some clinical and echocardiographic elements, such as age, atrial fibrillation, depressed right ventricular systolic function and emergency surgery, were associated as predictors of low cardiac output syndrome.

Estimated continuous cardiac output based on pulse wave transit time in critically ill children: a report of two cases / Débito cardíaco contínuo estimado baseado no tempo de trânsito da onda de pulso em crianças em estado crítico: relato de dois casos

ABSTRACT Cardiac output is an essential determinant of oxygen delivery, although unreliably measured on clinical examination and routine monitoring. Unfortunately, cardiac output monitoring is rarely performed in pediatric critical care medicine, with a limited availability of accurate methods for children. Herein, we report two pediatric cases in which noninvasive pulse-wave transit time-based cardiac output monitoring (esCCO, Nihon Kohden, Tokyo, Japan) was used. The esCCO system calculates cardiac output continuously by using the negative correlation between stroke volume and pulse wave transit time and requires only electrocardiogram monitoring, noninvasive blood pressure, and pulse oximetry signals. Before starting its use, esCCO should be calibrated, which can be done using patient information (gender, age, height, and body weight) or entering cardiac output values obtained by other methods. In both cases, when calibrations were performed using patient information, the agreement between esCCO and echocardiographic measurements was poor. However, after calibration with transthoracic echocardiography, the cardiac output values obtained by both methods remained similar after 2 hours and 18 hours. The results indicate that the esCCO system is suitable for use in children; however, further studies are needed to optimize its algorithm and determine its accuracy, precision, and trend in children.

RESUMO O débito cardíaco é um determinante importante do fornecimento de oxigênio, embora a sua mensuração seja realizada de forma pouco confiável no exame clínico e no monitoramento de rotina. Infelizmente, o monitoramento do débito cardíaco raramente é realizado na medicina intensiva pediátrica, com disponibilidade limitada de métodos precisos para crianças. Relatamos aqui dois casos pediátricos nos quais utilizouse o monitoramento não invasivo do débito cardíaco por meio da análise do tempo de trânsito de ondas de pulso (esCCO, Nihon Kohden, Tóquio, Japão). O sistema esCCO calcula o débito cardíaco continuamente pela correlação negativa entre o volume sistólico e o tempo de trânsito de ondas de pulso e requer apenas o monitoramento por eletrocardiograma, pressão arterial não invasiva e sinais de oximetria de pulso. Antes de iniciar seu uso, o esCCO deve ser calibrado, o que pode ser feito com informações do paciente (sexo, idade, altura e peso corporal) ou informando os valores do débito cardíaco obtidos mediante outros métodos. Em ambos os casos, quando as calibragens foram realizadas com informações do paciente, a concordância entre o débito cardíaco contínuo estimado e as medidas ecocardiográficas foi insatisfatória. Entretanto, após a calibragem com ecocardiografia transtorácica, os valores do débito cardíaco obtidos pelos dois métodos permaneceram semelhantes após 2 horas e 18 horas. Os resultados indicam que o sistema esCCO pode ser útil em crianças; entretanto, são necessários mais estudos para otimizar seu algoritmo e determinar sua exatidão, precisão e tendência em crianças.

Diseño y validación de riesgo de síndrome bajo gasto cardíaco en la cirugía valvular

Introducción: La incidencia del síndrome bajo gasto cardíaco postoperatorio es variable en las distintas series publicadas, desde 4 % hasta 15 %, con una mortalidad que se aproxima al 20 %. Si bien en enfermos mayores de 70 años el síndrome puede estar presente hasta en un 63 %, a pesar del desarrollo de mejores técnicas de cardioprotección y cuidados postoperatorios, la incidencia de este síndrome en poblaciones de alto riesgo no se ha modificado en una proporción significativa. Objetivo: Diseñar y validar un modelo predictivo de síndrome de bajo gasto cardíaco postoperatorio a través de factores de riesgo. Métodos: Se realizó un estudio analítico de casos y controles en pacientes con síndrome de bajo gasto cardíaco posoperatorio, atendidos en el Centro de Cardiología y Cirugía Cardiovascular del Hospital Provincial Docente Saturnino Lora de la provincia Santiago de Cuba, en un periodo 2019-2021. Se empleó la regresión logística con ajustes para obtener el modelo. Resultados: Los factores de riesgo predictores de mayor valor fue edad > 65 años, función de ventrículo derecho disminuida, el tiempo de pinzamiento aórtico, sangrado postoperatorio que fueron los que arrojó el modelo de regresión logística. Se realizó su validación interna por división de datos. Conclusiones: El modelo predictivo elaborado a partir de la regresión logística quedó compuesto por los predictores: edad > 65 años, el tiempo de pinzamiento aórtico > 90 minutos y el sangrado posoperatorio prolongado; presentó buen ajuste y poder discriminante, sobre todo valor predictivo positivo.

Introduction: The incidence of postoperative low cardiac output syndrome is variable in the different published series, from 4% to 15%, with a mortality approaching 20%. Although in patients over 70 years of age the syndrome may be present in up to 63%, despite the development of better cardioprotection techniques and postoperative care, the incidence of this syndrome in high-risk populations has not changed in a significant proportion. Objective: To design and validate a predictive model of postoperative low cardiac output syndrome through risk factors. Methods: An analytical, case-control study was conducted in patients with postoperative low cardiac output syndrome attended at the Center for Cardiology and Cardiovascular Surgery of the Saturnino Lora Teaching Provincial Hospital in Santiago de Cuba, in the period 2019-2021. Logistic regression with adjustments to obtain the model was used. Results: The highest value predictor risk factors are: age > 65 years, decreased right ventricular function, aortic clamping time, postoperative bleeding, which were the ones that yielded the logistic regression model. Internal validation was performed by data division. Conclusions: The predictive model developed from logistic regression was composed of the predictors: age > 65 years, aortic clamping time > 90 minutes and prolonged postoperative bleeding. It presented good fit and discriminant power, especially positive predictive value.

Monitorización hemodinámica integrada: clínica, gasométrica y ecocardiográfica / Integrated hemodynamic monitoring: clinical, gasometric and echocardiographic / Monitorização hemodinâmica integrada: clínica, gasométrica e ecocardiográfica

Introducción: la monitorización hemodinámica constituye un conjunto de técnicas y parámetros que permiten valo rar si la función cardiovascular es la adecuada para mantener la perfusión y la oxigenación tisular que permita sa tisfacer las demandas metabólicas del organismo, valorar el estado y el comportamiento del sistema cardiovascular, orientando sobre la mejor estrategia terapéutica. La presente revisión busca proporcionar una descripción general e integrada de las diferentes técnicas de monitorización, así como aspectos fisiológicos relevantes para su entendi miento y empleo terapéutico. La monitorización hemodinámica acompañada de un adecuado conocimiento de la fisiología cardiovascular permite determinar el estado del sistema cardiovascular, la condición hemodinámica del paciente y la estrategia terapéutica requerida. Su interpretación debe partir de la integración y la correlación de diversos parámetros hemodinámicos.

Introduction: hemodynamic monitoring is a set of techniques and parameters that allow evaluating whether cardio vascular function is adequate to maintain tissue perfusion and oxygenation to satisfy metabolic demands of the or ganism, assess the condition and behavior of the cardiovascular system, providing guidance on the best therapeutic strategy. This review seeks to provide a general and integrated description of the different monitoring techniques, as well as physiological aspects relevant to their understanding and therapeutic use. Hemodynamic monitoring accompanied by an adequate knowledge of cardiovascular physiology allows to determine the state of the cardiovascular system, hemodynamic condition of the patient and therapeutic strategy required, its interpretation must start from the integration and correlation of different hemodynamic parameters.

Introdução: a monitorização hemodinâmica constitui um conjunto de técnicas e parâmetros que permitem avaliar se a função cardiovascular é adequada para manter a perfusão e oxigenação tecidual que permite satisfazer as exi gências metabólicas do organismo, avaliar o estado e comportamento do sistema cardiovascular, orientando sobre a melhor estratégia terapêutica. Esta revisão procura fornecer uma descrição geral e integrada das diferentes técnicas de monitorização, bem como aspectos fisiológicos relevantes para a sua compreensão e utilização terapêutica. A monitorização hemodinâmica acompanhada de um conhecimento adequado da fisiologia cardiovascular permite determinar o estado do sistema cardiovascular, a condição hemodinâmica do doente e a estratégia terapêutica neces sária, a sua interpretação deve partir da integração e correlação de vários parâmetros hemodinâmicos.

Agreement analysis of stroke volume and cardiac output measurement between a oscillometric device and transthoracic echocardiogram in normotensive individuals: a preliminary report

Abstract Introduction The evaluation of stroke volume (SV) is useful in research and patient care. To accomplish this, an ideal device should be noninvasive, continuous, reliable, and reproducible. The Mobil-O-Graph (MOG) is a noninvasive oscillometric matrix validated for measuring aortic and peripheral blood pressure, which through conversion algorithms can estimate hemodynamic parameters. Objectives To compare the MOG measurement of stroke volume, cardiac output, and cardiac index with the transthoracic echocardiogram (TTE). Methods Healthy volunteers aged 18 years or older were included. Two-dimensional TTEs were performed by a single operator. Subsequently, the measurement of noninvasive hemodynamics with MOG was performed with the operator blind to the results of the echocardiogram. Correlation analyses between stroke volume, cardiac output, and cardiac index parameters were performed. The degree of agreement between the methods was verified using the Bland-Altman method. Results A total of 38 volunteers were enrolled with a mean age of 27.6 ± 3.8 years; 21 (55%) were male The SV by TTE was 76.8 ± 19.5 mL and 75.7 ± 19.3 mL by MOG, Rho = 0.726, p< 0.0001. The CO by TTE was 5.04 ± 0.8 mL.min-1 and 5.1 ± 0.8 mL.min-1 by MOG Rho = 0.510, p= 0.001. Bland-Altman plots showed a good concordance between the two techniques. Conclusions Our study shows that the measurement of SV and CO by noninvasive hemodynamics with the MOG device offers a good concordance with the TTE with very few values beyond the confidence limits.

Comparative study between suprasternal and apical windows: a user-friendly cardiac output measurement for the anesthesiologist

Abstract Introduction Transthoracic echocardiography is a safe and readily available tool for noninvasive monitoring of Cardiac Output (CO). The use of the suprasternal window situated at the sternal notch can be an alternative approach for estimating blood flow. The present study aimed to compare two methods of CO calculation. We compared the descending aorta Velocity-Time Integral (VTI) measurement from the suprasternal window view with the standard technique to determine CO that uses VTI measurements from the LVOT (Left Ventricular Outflow Tract) view. We also aimed to find out whether after basic training a non-echocardiographer operator can obtain reproducible measurements of VTI using this approach. Methods In the first part of the study, 26 patients without known cardiovascular diseases were evaluated and VTI data were acquired from the suprasternal window by a non-echocardiographer and an echocardiographer. Next, 17 patients were evaluated by an echocardiographer only and VTI and CO measurements were obtained from suprasternal and apical windows. Data were analyzed using the Bland and Altman method (BA), correlation and regression. Results We found a strong correlation between measurements obtained by a non-expert and an expert echocardiographer and detected that an inexperienced trainee can acquire VTI measurements from the suprasternal window view. Regarding agreement between CO measurements, data obtained showed a positive correlation and the Bland and Altman analysis presented a total variation of 38.9%. Conclusion Regarding accuracy, it is likely that TTE (Transthoracic Echocardiogram) measurements of CO from the suprasternal window view are comparable to other minimally invasive techniques currently available. Due to its user-friendliness and low cost, it can be a convenient technique for obtaining perioperative hemodynamic measurements, even by inexperienced operators.

The Role of Shunt Occlusion During Extracorporeal Life Support

ABSTRACT Introduction: The current recommendation for systemic to pulmonary artery shunt (SPS) patients requiring extracorporeal life support (ECLS) is to keep the shunt open, maintaining a higher pump flow. The practice in our center is to totally occlude the shunt while on ECLS, and we are presenting the outcome of this strategy. Methods: This is a retrospective analysis of patients who underwent SPS for cyanotic congenital heart disease with decreased pulmonary blood flow and required postoperative ECLS between January 2016 and December 2020. ECLS indication was excessive pulmonary blood flow, leading to either refractory low cardiac output syndrome (LCOS) or cardiac arrest. All patients had their shunts totally occluded soon after ECLS establishment. Results: Of the 27 SPS patients who needed postoperative ECLS (13 refractory LCOS, 14 extracorporeal cardiopulmonary resuscitation), wherein the strategy of occluding the shunt on ECLS initiation was followed, 16 (59.3 %) survived ECLS weaning and eight (29.6%) survived to discharge. Conclusion: Increased flow to maintain systemic circulation for a SPS patient while on ECLS is an accepted strategy, but it should not be applied universally. A large subset of SPS patients, who require ECLS either due to cardiac arrest or refractory LCOS due to excessive pulmonary flow, might benefit from complete occlusion of the shunt soon after commencement of ECLS, especially in cases with frank pulmonary edema or haemorrhage in the pre-ECLS period. A prospective randomized trial could be ethically justified for the subset of patients receiving ECLS for the indication of excessive pulmonary blood flow.

Redo Total Aortic Arch Replacement in Patients with Aortic Dissection After Open-Heart Surgery and Long-Term Follow-Up Results

ABSTRACT Introduction: The objectives of this study were to investigate the main treatment strategies and long-term follow-up results of aortic dissection surgery after open-heart surgery (ADSOHS) and to analyze the risk factors that cause ADSOHS. Methods: One hundred thirty-seven patients with ADSOHS hospitalized in our hospital from January 2009 to December 2018 were selected as the research object. Long-term follow-up results, complications, mortality, and changes of cardiac function before and after operation were used to explore the value of Sun's operation. Results: The length of stay in intensive care unit of these 137 patients ranged from 9.5 to 623.75 hours (average of 76.41±97.29 hours), auxiliary ventilation time ranged from 6.0 to 259.83 hours (average of 46.16±55.59 hours), and hospital stay ranged from six to 85 days (average of 25.06±13.04 days). There were seven cases of postoperative low cardiac output, 18 cases of coma and stroke, and six cases of transient neurological dysfunction. A total of 33 patients died; 19 patients died during the perioperative period, 18 died during Sun's operation and one died during other operation; and 14 patients died during follow-up (January 2021), 12 cases of Sun's operation and two cases of other operations. Conclusion: ADSOHS treatment strategy is of high application value, and the risk of neurological complications and mortality is low. The main risk factors are postoperative low cardiac output, coma, stroke, and transient neurological dysfunction. The extracorporeal circulation time is relatively long. Short- and long-term follow-up effects are good, and it is worthy of clinical promotion.

Study on the consistency between thoracic electrical bioimpedance and pulse index continuous cardiac output in hemodynamic monitoring of elderly patients with septic shock / 中华老年医学杂志

Objective:The hemodynamic parameters of elderly patients with septic shock were measured simultaneously with pulse index continuous cardiac output(PiCCO)and thoracic electrical bioimpedance(TEB)to evaluate the accuracy of TEB and to provide empirical evidence for its clinical use.Methods:A total of 24 elderly patients with septic shock admitted to the intensive care unit of our hospital between July 2021 and December 2021 were retrospectively recruited.TEB and PiCCO hemodynamic monitoring were performed continuously in all patients, and hemodynamic data were collected for statistical analysis.Results:Cardiac output, cardiac index, stroke volume, stroke index and systemic vascular resistance measured by the two methods had no significant difference( P>0.05). The 95% confidence intervals in the Bland-Altman plots for cardiac output, CI, stroke volume, stroke index, and systemic vascular resistance were(-1.18, 1.25), (-0.65, 0.71), (-24.23, 37.00), (-12.93, 19.26)and(397.11, 425.83). In the Bland-Altman plots for cardiac output, cardiac index, stroke volume and systemic vascular resistance, 4.17% of the points(1/24)fell outside of the 95% confidence interval, and in the Bland-Altman plots for stroke index, 8.33% of the points(2/24)fell outside of the 95% confidence interval. Conclusions:TEB and PiCCO have good consistency in evaluating the hemodynamics of elderly patients with septic shock.Therefore, TEB can be recommended for community hospitals and used in elderly patients.

Decreased cardiac output: an integrative review / Disminución del gasto cardíaco: revisión integradora / Débito cardíaco diminuído: revisão integrativa

ABSTRACT Objective: to identify, in the scientific literature, the defining characteristics and contributing factors (related factors, associated conditions and populations at risk) for nursing diagnosis decreased cardiac output. Method: an integrative literature review, conducted between September and October 2020, with an update in March 2022, in the MEDLINE via PubMed, LILACS, SciELO, CINAHL and EMBASE databases. Using acronym PEO, studies published in the last 10 years in Portuguese, English and Spanish were included. A descriptive analysis was carried out to present the elements mapped in the literature. Results: analysis of 31 articles identified different elements, highlighting 4 new related factors: hyperglycemic stress, prone position, left lateral position, sleep deprivation. Individuals with a history of cardiovascular disease and males were identified as possible populations at risk. Final considerations: the elements for decreased cardiac output, identified in the literature, add evidence that justifies the permanence of this diagnosis in the NANDA-I classification.

RESUMEN Objetivo: identificar, en la literatura científica, las características definidoras y los factores contribuyentes (factores relacionados, condiciones asociadas y poblaciones de riesgo) para el diagnóstico de enfermería de gasto cardíaco disminuido. Método: revisión integrativa de la literatura, realizada entre septiembrey octubre de 2020, con actualización en marzo de 2022, en las bases de datos MEDLINE vía PubMed, LILACS, SciELO, CINAHL y EMBASE. Utilizando la sigla PEO, se incluyeron estudios publicados en los últimos 10 años en portugués, inglés y español. Se realizó un análisis descriptivo para presentar los elementos mapeados en la literatura. Resultados: el análisis de 31 artículos identificó diferentes elementos, con énfasis en 4 nuevos factores relacionados: estrés hiperglucémico, posición prona, posición lateral izquierda, privación del sueño. Las personas con antecedentes de enfermedad cardiovascular y los hombres se identificaron como posibles poblaciones en riesgo. Consideraciones finales: los elementos para gasto cardíaco disminuido, identificados en la literatura, suman evidencias que justifican la permanencia de este diagnóstico en la clasificación NANDA-I.

RESUMO Objetivo: identificar, na literatura científica, as características definidoras e fatores contribuintes (fatores relacionados, condições associadas e populações em risco) para o diagnóstico de enfermagem débito cardíaco diminuído. Método: revisão integrativa da literatura, conduzida entre setembro e outubro de 2020, com atualização em março de 2022, nas bases de dados MEDLINE via PubMed, LILACS, SciELO, CINAHL e EMBASE. Com uso do acrônimo PEO, foram incluídos estudos publicados nos últimos 10 anos em português, inglês e espanhol. Realizouse análise descritiva para apresentar os elementos mapeados na literatura. Resultados: análise de 31 artigos identificou diferentes elementos, com destaque para 4 novos fatores relacionados: estresse hiperglicêmico, posição prona, posição lateral esquerda, privação do sono. Indivíduos com história de doença cardiovascular e do sexo masculino foram apontados como possíveis populações em risco. Considerações finais: os elementos para débito cardíaco diminuído, identificados na literatura, agregam evidências que justificam a permanência desse diagnóstico na classificação da NANDA-I.

Factores clínicos y ecocardiográficos asociados al bajo gasto cardíaco posoperatorio en pacientes con tratamiento quirúrgico cardiovascular / Clinical and echocardiographic factors associated with the postoperative low cardiac output in patients with cardiovascular surgical treatment i: en

Introducción: Entre las diferentes complicaciones que surgen en el periodo posoperatorio inmediato, el bajo gasto cardíaco presenta mayor morbilidad y mortalidad asociadas, con una incidencia de hasta 45,0 %. Objetivo: Determinar los factores relacionados con la aparición posoperatoria del bajo gasto cardíaco en pacientes con tratamiento quirúrgico cardiovascular y circulación extracorpórea, según variables demográficas, clínicas y ecocardiográficas. Métodos: Se realizó una investigación analítica, de casos y controles, la cual incluyó a pacientes que recibieron tratamiento quirúrgico cardíaco en el Servicio de Cardiología y Cirugía Cardiovascular del Hospital Provincial Clinicoquirúrgico Docente Saturnino Lora de Santiago de Cuba, desde enero hasta diciembre de 2019. Cada grupo de estudio estuvo conformado por 43 integrantes, para lo cual se consideró la presencia del síndrome de bajo gasto cardíaco (casos) o no (controles). Resultados: En la serie predominaron los pacientes menores de 65 años de edad en ambos grupos de estudio (51,2 y 73,5 % para casos y controles, respectivamente), así como el sexo masculino (60,9 %); de igual modo, resultó más frecuente la intervención quirúrgica de emergencia (80,2 %). La fibrilación auricular y la función sistólica del ventrículo derecho presentaron alta significación estadística (p<0,05). Conclusiones: Algunos elementos clínicos y ecocardiográficos (edad, fibrilación auricular, función sistólica de los ventrículos izquierdo y derecho, así como intervención quirúrgica de emergencia) se asociaron de manera independiente a la aparición del bajo gasto cardíaco.

Introduction: Among the different complications that arise in the immediate postoperative period, the low cardiac output presents higher associated morbidity and mortality, with an incidence of up to 45.0 %. Objective: To determine the factors related to the postoperative emergence of the low cardiac output in patients with cardiovascular surgical treatment and extracorporeal circulation, according to demographic, clinical and echocardiographic variables. Methods: An analytic, cases and controls investigation was carried out, which included patients that received heart surgical treatment in the Cardiology and Cardiovascular Surgery Service of Saturnino Lora Teaching Clinical Surgical Provincial Hospital in Santiago de Cuba, from January to December, 2019. Each study group was conformed by 43 members, for which was considered the presence (cases) or not (controls) of the low cardiac output syndrome. Results: In the series there was a prevalence of the patients under 65 years in both study groups (51.2 and 73.5 % for cases and controls, respectively), as well as the male sex (60.9 %); in a same way, the emergency surgical intervention was the most frequent (80.2 %). The atrial fibrillation and the systolic function of the right ventricle presented high statistical significance (p <0.05). Conclusions: Some clinical and echocardiographic elements (age, atrial fibrillation, systolic function of the left and right ventricles, as well as emergency surgical intervention) were associated in an independent way with the emergence of the low cardiac output.

Retrospective Evaluation of Platelet-Leukocyte Indices and Cardiac Surgical Outcomes in Acyanotic Heart Disease Patients with Pulmonary Hypertension (REPLICA-PH)

Abstract Introduction: Acyanotic congenital heart disease (ACHD) patients with pulmonary hypertension (PH) are prone to postoperative complications, and characterization of the risk profile continues to fail in identifying inflammatory predilection. Our objective is to investigate the role of platelet-leukocyte indices (neutrophil-lymphocyte ratio [NLR], platelet-lymphocyte ratio [PLR], and systemic immune-inflammation index [SII] [neutrophil × platelet/lymphocyte]) in predicting poor outcomes following cardiac surgery in ACHD cohort with preoperative PH. Methods: This single-center, retrospective risk-predictive study included ACHD patients undergoing surgical correction at our tertiary cardiac center between January 2015 and December 2019. Standard institutional perioperative management protocol was followed, and poor postoperative outcome was defined as ≥ 1 of: low cardiac output syndrome, new-onset renal failure, prolonged mechanical ventilation (MV > 24 hours), stroke, sepsis, and/or death. Results: One hundred eighty patients out of 1,040 (17.3%) presented poor outcome. On univariate analysis, preoperative factors including right ventricular systolic pressure (RVSP) (PH-severity marker), congestive heart failure, albumin, NLR, PLR, SII, and aortic cross-clamping (ACC) and cardiopulmonary bypass (CPB) times predicted poor outcome. However, on multivariate analysis, RVSP, NLR, SII, and ACC and CPB times emerged as independent predictors. An NLR, SII prognostic cutoff of 3.33 and 860.6×103/mm3 was derived (sensitivity: 77.8%, 78.9%; specificity: 91.7%, 82.2%; area under the curve: 0.871, 0.833). NLR and SII values significantly correlated with postoperative MV duration, mean vasoactive-inotropic scores, and length of intensive care unit and hospital stay (P<0.001). Conclusion: Novel parsimonious, reproducible plateletleukocyte indices present the potential of stratifying the risk in congenital cardiac surgical patients with pre-existing PH.

Comparative Study of Cardiac Output Measurement by Regional Impedance Cardiography and Thermodilution Method in Patients Undergoing off Pump Coronary Artery Bypass Graft Surgery

Background:An ideal CO monitor should be noninvasive, cost effective, reproducible, reliable during various physiological states. Limited literature is available regarding the noninvasive CO monitoring in open chest surgeries. Aim: The aim of this study was to compare the CO measurement by Regional Impedance Cardiography (RIC) and Thermodilution (TD) method in patients undergoing off pump coronary artery bypass graft surgery (OPCAB). Settings and Design: We conducted a prospective observational comparative study of CO measurement by the noninvasive RIC method using the NICaSHemodynamicNavigator systemand the gold standardTDmethod using pulmonary artery catheterin patients undergoingOPCAB.Atotal of 150 data pair from the two CO monitoring techniques were taken from 15 patients between 40-70 years at various predefined time intervals of the surgery. Patients and Methods: We have tried to find out the accuracy, precision and cost effectiveness of the newer RIC technique. Mean CO, bias and precision were compared for each pair i.e.TD-CO and RIC-CO as recommended by Bland and Altman.The Sensitivity and specificity of cutoff value to predict change in TD-CO was used to create a Receiver operating characteristic or ROC curve. Results: Mean TD-CO values were around 4.52 ± 1.09 L/min, while mean RIC- CO values were around 4.77± 1.84 L/min. The difference in CO change was found to be statistically not significant (p value 0.667). The bias was small (-0.25). The Bland Altman plot revealed a mean difference of -0.25 litres.The RIC method had a sensitivity of 55.56 % and specificity of 33.33 % in predicting 15% change in CO of TD method and the total diagnostic accuracy was 46.67%. Conclusion: A fair correlation was found between the two techniques. The RIC method may be considered as a promising noninvasive, potentially low cost alternative to the TD technique of hemodynamic measurement.