Effects of Different Tidal Volumes and PEEPs on Cardiac Output in Pigs Measured by Pulmonary Artery Catheter， Pulse Contour Analysis and Transpulmonary Thermodilution / 中山大学学报(医学科学版)

ObjectiveTo compare the effects of different tidal volumes and positive end expiratory pressures （PEEPs） during mechanical ventilation on the cardiac output of pigs measured by pulmonary artery catheter， transpulmonary thermodilution and pulse contour analysis， and to explore their consistency in cardiac output determination. MethodsTwelve experimental pigs were selected and randomly divided into 3 groups， with 4 pigs in each. Cardiac output was measured by different methods， control group by pulmonary artery catheter， group A by transpulmonary thermodilution and group B by pulse contour analysis. Then we compared the effects of different tidal volumes and PEEPs on the cardiac output of pigs and to explore the consistency. The correlation coefficient between pulse contour analysis and pulmonary artery catheter was r=0.754， and they were positively correlated. The correlation coefficient between transpulmonary thermodilution and pulmonary artery catheter was r=0.771， and they were positively correlated. In determining cardiac output， pulse contour analysis was consistent with pulmonary artery catheter， with a relative error of 13.5% between them； transpulmonary thermodilution was consistent with pulmonary artery catheter， with a relative error of 12.9% between them. The cardiac output decreased significantly along with the increase of tidal volumes or PEEPs and the differences were statistically significant （P<0.05） ConclusionPulmonary artery catheter， transpulmonary thermodilution and pulse contour analysis are well consistent with each other in measuring the cardiac output of pigs. The pigs’cardiac output gradually decreased along with the increase of tidal volumes or PEEPs during mechanical ventilation.

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.

Correlación del gasto cardiaco por fórmula de continuidad a través de ecocardiografía transtorácica vs termodilución por Swan-Ganz en la Unidad de Cuidados Intensivos / Correlation of cardiac output by continuity formula through transthoracic echocardiography vs thermodilution by Swan-Ganz in the Intensive Care Unit / Correlação do débito cardíaco pela fórmula de continuidade através da ecocardiografia transtorácica vs termodiluição por Swan-Ganz na unidade de terapia intensiva

Resumen: Introducción: la termodilución se considera el estándar de referencia para la medición del gasto cardiaco. Durante las últimas décadas la aparición de otros métodos menos invasivos ha resultado útil para determinar el gasto cardiaco. El objetivo del estudio es analizar la correlación entre el gasto cardiaco obtenido por ecocardiografía transtorácica mediante el método de continuidad y termodilución pulmonar por catéter de Swan-Ganz. Material y métodos: estudio prospectivo, descriptivo, transversal realizado en la Unidad de Cuidados Intensivos del Hospital General Las Américas. A los pacientes se les colocó catéter Swan-Ganz; se realizó medición de gasto cardiaco por ecocardiografía; posteriormente cuantificación de gasto cardiaco por termodilución pulmonar durante marzo de 2021 a agosto de 2022. Resultados: se compararon 58 mediciones de gasto cardiaco (GC) por Swan-Ganz con una mediana de 4.95 (rango 3.1-7.2), y GC por ecocardiografía con una mediana 4.93 (rango 3.2-7.0). La diferencia de medias para la medición de gasto cardiaco por Swan-Ganz fue de 5.20 (95% IC 4.56-5.84, p < 0.0001), comparado con gasto cardiaco por termodilución 5.19 (95% IC 4.56-5.81, p < 0.0001). Conclusiones: existe correlación significativa entre el gasto cardiaco medido por termodilución y ecocardiografía; se le considera una alternativa confiable para la determinación del gasto cardiaco.

Abstract: Introduction: thermodilution considered the reference standard for measuring cardiac output. During the last decades, the appearance of other less invasive methods has been useful to determine cardiac output. The aim of the study is to analyze the correlation between cardiac output obtained by transthoracic echocardiography by continuity method and pulmonary thermodilution by Swan-Ganz catheter. Material and methods: prospective, descriptive, cross-sectional study carried out in the Intensive Care Unit of the Hospital General Las Américas, the patients underwent a Swan-Ganz catheter; cardiac output was measured by echocardiography; subsequently, quantification of cardiac output by pulmonary thermodilution during March 2021 to August 2022. Results: fifty-eight measurements of cardiac output by Swan-Ganz with a median of 4.95 (range 3.1-7.2) and CO by echocardiography with a median of 4.93 (range 3.2-7.0) were compared. The difference in means for the measurement of cardiac output by Swan-Ganz was 5.20 (95% CI 4.56-5.84 p < 0.0001), compared to cardiac output by thermodilution 5.19 (95% CI 4.56-5.81 p < 0.0001). Conclusions: there is a significant correlation between cardiac output measured by thermodilution and echocardiography; being considered a reliable alternative for the determination of cardiac output.

Resumo: Introdução: a termodiluição é considerada o padrão de referência para a medida do débito cardíaco. Nas últimas décadas, o surgimento de outros métodos menos invasivos mostrou-se útil para a determinação do débito cardíaco. O objetivo do estudo é analisar a correlação entre o débito cardíaco obtido pela ecocardiografia transtorácica pelo método da continuidade e a termodiluição pulmonar pelo cateter de Swan-Ganz. Material e métodos: estudo prospectivo, descritivo, transversal, realizado na Unidade de Terapia Intensiva do Hospital Geral Las Américas, onde foi colocado cateter de Swan-Ganz; o débito cardíaco foi medido por ecocardiografia; posteriormente, quantificação do débito cardíaco por termodiluição pulmonar no período de março de 2021 a agosto de 2022. Resultados: foram comparadas 58 medidas do débito cardíaco por Swan-Ganz com uma mediana de 4.95 (intervalo 3.1-7.2), e GC por ecocardiografia com uma mediana de 4.93 (intervalo 3.2-7.0). A diferença média para medição do débito cardíaco por Swan-Ganz foi de 5.20 (IC 95% 4.56-5.84 p < 0.0001), em comparação com o débito cardíaco por termodiluição 5.19 (95% CI 4.56-5.81 p < 0.0001). Conclusões: existe uma correlação significativa entre o débito cardíaco medido por termodiluição e ecocardiografia; considerando-o uma alternativa confiável para a determinação do débito cardíaco.

Caracterização do comprometimento pulmonar associado à COVID-19 em pacientes com necessidade de ventilação mecânica / Characterization of pulmonary impairment associated with COVID-19 in patients requiring mechanical ventilation

RESUMO Objetivo: Detectar precocemente a instabilidade respiratória e hemodinâmica para caracterizar o comprometimento pulmonar em pacientes com COVID-19 grave. Métodos: Analisamos retrospectivamente os dados colhidos de pacientes com COVID-19 que apresentaram insuficiência respiratória aguda com necessidade de intubação e ventilação mecânica. Utilizamos a avaliação da termodiluição transpulmonar por meio do dispositivo PiCCO™. Foram coletados os dados demográficos, respiratórios, hemodinâmicos e ecocardiográficos dentro das primeiras 48 horas após a admissão. Para resumir os dados, utilizamos estatística descritiva. Resultados: Entre 22 de março e 7 de abril de 2020, foram admitidos 23 pacientes com COVID-19 grave. Foram monitorados com o dispositivo PiCCO™ 12 (22,6%) deles. Quando da admissão, o volume diastólico final global indexado era normal (média de 738,8mL ± 209,2) e, na hora 48, encontrava-se moderadamente aumentado (879mL ± 179), enquanto o índice cardíaco se achava abaixo do normal (2,84 ± 0,65). Todos os pacientes revelaram a presença de água extravascular pulmonar acima de 8mL/kg na admissão (17,9 ± 8,9). Não identificamos qualquer evidência de origem cardiogênica. Conclusão: No caso de pneumonia grave por COVID-19, o quadro hemodinâmico e respiratório é compatível com edema pulmonar sem evidência de origem cardiogênica, o que favorece o diagnóstico de síndrome do desconforto respiratório agudo.

ABSTRACT Objective: To detect early respiratory and hemodynamic instability to characterize pulmonary impairment in patients with severe COVID-19. Methods: We retrospectively analyzed data collected from COVID-19 patients suffering from acute respiratory failure requiring intubation and mechanical ventilation. We used transpulmonary thermodilution assessment with a PiCCO™ device. We collected demographic, respiratory, hemodynamic and echocardiographic data within the first 48 hours after admission. Descriptive statistics were used to summarize the data. Results: Fifty-three patients with severe COVID-19 were admitted between March 22nd and April 7th. Twelve of them (22.6%) were monitored with a PiCCO™ device. Upon admission, the global-end diastolic volume indexed was normal (mean 738.8mL ± 209.2) and moderately increased at H48 (879mL ± 179), and the cardiac index was subnormal (2.84 ± 0.65). All patients showed extravascular lung water over 8mL/kg on admission (17.9 ± 8.9). We did not identify any argument for cardiogenic failure. Conclusion: In the case of severe COVID-19 pneumonia, hemodynamic and respiratory presentation is consistent with pulmonary edema without evidence of cardiogenic origin, favoring the diagnosis of acute respiratory distress syndrome.

Asociación entre el índice de agua extravascular pulmonar y el balance hídrico en pacientes críticamente enfermos / Association between extravascular lung water index and fluid balance in critically ill patients / Associação entre água extravascular pulmonar indexada e balanço hídrico em pacientes em estado crítico

Resumen: Introducción: El balance hídrico positivo y el agua extravascular pulmonar medida por termodilución transpulmonar son factores independientes de mortalidad. La inclusión del valor de agua extravascular pulmonar indexada (EVLWi) durante la reanimación inicial impacta en la cantidad de líquido administrado. Aunque no existen antecedentes, buscar una asociación entre ambos parámetros puede llevar a un balance hídrico global negativo guiado por la cantidad de EVLWi. En este estudio retrospectivo se buscó la asociación entre EVLWi y balance hídrico y su impacto en la mortalidad. Material y métodos: Se realizó un estudio retrospectivo de cohortes con 20 casos para establecer la asociación entre agua extravascular pulmonar indexada medida por termodilución transpulmonar y balance hídrico total a las 24, 48 y 72 horas, así como con la mortalidad a 30 días. Resultados: Un valor de corte > 11 mL/kg de EVLWi se asoció con un incremento de la mortalidad; a las 24 horas RR 8.0 (95% IC 1.2146-52.6944, p = 0.0306), a las 48 horas RR 4.3778 (95% IC 1.1643-15.7177, p = 0.0286) y a las 72 horas con RR 3.5000 (95% IC 0.9497-12.8983, p = 0.0598). El valor de corte del balance hídrico fue ≥ 3.5 L, sin asociación con la mortalidad RR 0.1789 (95% IC 0.0125-2.5668, p = 0.2054) a las 24 horas, RR 0.5000 (95% IC 0.0854-2.9258, p = 0.4419) a las 48 horas y RR 0.3750 (95% IC 0.0610-2.3059, p = 0.2897) a las 72 horas. La asociación entre balance hídrico total y EVLWi fue r (2) Pearson = 0.01269. Conclusiones: El EVLWi > 11 mL/kg se asoció a un incremento en la mortalidad, a diferencia del balance hídrico. No encontramos correlación entre el balance hídrico y el EVLWi.

Abstract: Introduction: Positive fluid balance and extravascular lung water index (EVLWi) quantified by transpulmonary thermodilution have been important independent mortality prognostic factors. Including EVLWi to guide initial fluid reanimation therapy has a high impact in the amount of administered fluid. Although there is not enough evidence, search for an association between EVLWi and fluid balance could lead to a negative fluid balance driven by EVLWi to improve survival rates. In this retrospective study we search for the association between EVLWi, fluid balance and its impact on mortality. Material and methods: Retrospective, cohort study of 20 cases. We looked for any association between EVLWi by transpulmonary thermodilution and daily fluid balance at 24, 48 and 72 hours and reviewed mortality at 30 days. Results: An EVLWi cutoff value of > 11 mL/kg was associated with a higher mortality; on the first 24 hours with an RR 8.0 (95% CI 1.2146-52.6944, p = 0.0306), at 48 hours RR 4.3778 (95% CI 1.1643-15.7177, p = 0.0286) and at 72 hours RR 3.5000 (95% CI 0.9497-12.8983 p = 0.0598). Fluid balance cutoff value was established at ≥ 3.5 L, but we can't find any association with mortality, RR 0.1789 (95% CI 0.0125-2.5668, p = 0.2054) at 24 hours, RR 0.5000 (95% CI 0.0854-2.9258, p = 0.4419) at 48 hours y RR 0.3750 (95% CI 0.0610-2.3059, p = 0.2897) at 72 hours. The correlation between fluid balance and EVLWi was negative, Pearson's r (2) = 0.01269. Conclusions: EVLWi was associated to a higher mortality. We could not demonstrate an association between fluid balance and EVLWi.

Resumo: Introdução: O balanço hídrico positivo e a água extravascular pulmonar medida por termodiluição transpulmonar são fatores independentes da mortalidade. A inclusão do valor de água extravascular pulmonar indexada (EVLWi) durante a ressuscitação inicial impacta a quantidade de fluido entregue. Embora não haja precedente, buscar uma associação entre os dois parâmetros pode levar a um balanço hídrico global negativo guiado pela quantidade de EVLWi. Neste estudo retrospectivo, buscou-se a associação entre EVLWi e balanço hídrico e seu impacto na mortalidade. Material e métodos: Foi realizado um estudo de coorte retrospectivo com 20 casos para estabelecer a associação entre a água pulmonar extravascular indexada medida por termodiluição transpulmonar e balanço hídrico total em 24, 48 e 72 horas, bem como mortalidade em 30 dias. Resultados: Um valor de corte > 11 mL/kg de EVLWi foi associado a um aumento na mortalidade; às 24 horas RR 8.0 (95% IC 1.2146-52.6944, p = 0.0306), 48 horas RR 4.3778 (95% IC 1.1643-15.7177, p = 0.0286) e 72 horas com RR 3.5000 (95% IC 0.9497-12.8983 p = 0.0598). O valor de corte do balanço hídrico foi ≥ 3.5 L, sem associação com mortalidade RR 0.1789 (IC 95% 0.0125-2.5668, p = 0.2054) em 24 horas, RR 0.5000 (IC 95% 0.0854-2.9258 p = 0.4419) em 48 horas e RR 0.3750 (IC 95% 0.0610-2.3059 p = 0.2897) às 72 horas. A associação entre balanço hídrico total e EVLWi foi r 2 Pearson = 0.01269. Conclusões: EVLWi > 11 mL/kg foi associado a um aumento da mortalidade, em contraste com o balanço hídrico. Não encontramos correlação entre o balanço hídrico e o EVLWi.

Cardiac output monitoring: Technology and choice

The accurate quantification of cardiac output (CO) is given vital importance in modern medical practice, especially in high-risk surgical and critically ill patients. CO monitoring together with perioperative protocols to guide intravenous fluid therapy and inotropic support with the aim of improving CO and oxygen delivery has shown to improve perioperative outcomes in high-risk surgical patients. Understanding of the underlying principles of CO measuring devices helps in knowing the limitations of their use and allows more effective and safer utilization. At present, no single CO monitoring device can meet all the clinical requirements considering the limitations of diverse CO monitoring techniques. The evidence for the minimally invasive CO monitoring is conflicting; however, different CO monitoring devices may be used during the clinical course of patients as an integrated approach based on their invasiveness and the need for additional hemodynamic data. These devices add numerical trend information for anesthesiologists and intensivists to use in determining the most appropriate management of their patients and at present, do not completely prohibit but do increasingly limit the use of the pulmonary artery catheter.

Ultrasound cardiac output monitor and thermodilution for cardiac function monitoring in critical patients: a Meta-analysis / 中华危重病急救医学

Objective@#To assess the differences between ultrasound cardiac output monitor (USCOM) and thermodilution (TD) systematically in cardiac function monitoring of critically ill patients.@*Methods@#The Chinese and English literatures about the clinical trials which using USCOM and TD to monitor cardiac function published in CNKI, Wanfang database, China biomedical literature database, VIP database, China Clinical Trial Registration Center, PubMed, Embase and Cochrane Library were searched by computer from the establishment to December 2018. Some indicators, like cardiac output (CO), cardiac index (CI), stroke volume (SV) and other parameters were used to evaluate cardiac function. Literature search, quality evaluation and data extraction were conducted independently by two authors. The tailored Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) was used for literature quality evaluation. EndNote X6 was used for literature screening and management. RevMan 5.3 was used for Meta-analysis. Funnel chart analysis was used for publication bias.@*Results@#A total of 26 studies involving 772 patients were included. Among them, there were 5 literatures found that the agreements of cardiac function between the USCOM and TD methods were poor. Meta-analysis showed that there was no significant difference between the two methods in CO and CI monitoring [CO: mean difference (MD) = -0.06, 95% confidence interval (95%CI) was -0.17 to 0.05, P = 0.31; CI: MD = -0.04, 95%CI was -0.13 to 0.05, P = 0.38]. Subgroup analysis of different TD methods [pulmonary artery catheter (PAC), pulse indicator continuous cardiac output (PiCCO)] and different windows of USCOM ultrasonic probe [aorta (AA), pulmonary artery (PA)] in CO monitoring was not shown significant difference yet (PAC: MD = -0.07, 95%CI was -0.18 to 0.04, P = 0.23; PiCCO: MD = 0.09, 95%CI was -0.31 to 0.50, P = 0.65; AA windows: MD = -0.14, 95%CI was -0.31 to 0.02, P = 0.09; PA windows: MD = -0.00, 95%CI was -0.15 to 0.14, P = 0.95; AA/PA windows: MD = 0.23, 95%CI was -0.40 to 0.86, P = 0.47). However, the difference in SV was statistically significant between the USCOM and TD method (MD = 1.48, 95%CI was 0.04 to 2.92, P = 0.04). Funnel chart showed that the literature distribution of CO and CI monitoring were basically symmetrical, indicating that the bias of literature publication is small.@*Conclusion@#USCOM has good consistency with TD method in monitoring the cardiac function parameters of CO and CI, and different windows of ultrasonic probe of USCOM have no significant influence on the monitoring results, but there is significant difference in the consistency of the two methods in SV monitoring.

Accuracy and Efficacy of Impedance Cardiography as a Non-Invasive Cardiac Function Monitor

PURPOSE: The most common method of monitoring cardiac output (CO) is thermodilution using pulmonary artery catheter (PAC), but this method is associated with complications. Impedance cardiography (ICG) is a non-invasive CO monitoring technique. This study compared the accuracy and efficacy of ICG as a non-invasive cardiac function monitoring technique to those of thermodilution and arterial pressure contour. MATERIALS AND METHODS: Sixteen patients undergoing liver transplantation were included. Cardiac index (CI) was measured by thermodilution using PAC, arterial waveform analysis, and ICG simultaneously in each patient. Statistical analysis was performed using intraclass correlation coefficient (ICC) and Bland-Altman analysis to assess the degree of agreement. RESULTS: The difference by thermodilution and ICG was 1.13 L/min/m², and the limits of agreement were −0.93 and 3.20 L/min/m². The difference by thermodilution and arterial pressure contour was 0.62 L/min/m², and the limits of agreement were −1.43 and 2.67 L/min/m². The difference by arterial pressure contour and ICG was 0.50 L/min/m², and the limits of agreement were −1.32 and 2.32 L/min/m². All three percentage errors exceeded the 30% limit of acceptance. Substantial agreement was observed between CI of thermodilution with PAC and ICG at preanhepatic and anhepatic phases, as well as between CI of thermodilution and arterial waveform analysis at preanhepatic phase. Others showed moderate agreement. CONCLUSION: Although neither method was clinically equivalent to thermodilution, ICG showed more substantial correlation with thermodilution method than with arterial waveform analysis. As a non-invasive cardiac function monitor, ICG would likely require further studies in other settings.

Ultrasound cardiac output monitor and thermodilution for cardiac function monitoring in critical patients:a Meta-analysis / 中华危重病急救医学

Objective To assess the differences between ultrasound cardiac output monitor (USCOM) and thermodilution (TD) systematically in cardiac function monitoring of critically ill patients. Methods The Chinese and English literatures about the clinical trials which using USCOM and TD to monitor cardiac function published in CNKI, Wanfang database, China biomedical literature database, VIP database, China Clinical Trial Registration Center, PubMed, Embase and Cochrane Library were searched by computer from the establishment to December 2018. Some indicators, like cardiac output (CO), cardiac index (CI), stroke volume (SV) and other parameters were used to evaluate cardiac function. Literature search, quality evaluation and data extraction were conducted independently by two authors. The tailored Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) was used for literature quality evaluation. EndNote X6 was used for literature screening and management. RevMan 5.3 was used for Meta-analysis. Funnel chart analysis was used for publication bias. Results A total of 26 studies involving 772 patients were included. Among them, there were 5 literatures found that the agreements of cardiac function between the USCOM and TD methods were poor. Meta-analysis showed that there was no significant difference between the two methods in CO and CI monitoring [CO: mean difference (MD) =-0.06, 95％ confidence interval (95％CI) was -0.17 to 0.05, P = 0.31; CI: MD =-0.04, 95％CI was -0.13 to 0.05, P = 0.38]. Subgroup analysis of different TD methods [pulmonary artery catheter (PAC), pulse indicator continuous cardiac output (PiCCO)] and different windows of USCOM ultrasonic probe [aorta (AA), pulmonary artery (PA)] in CO monitoring was not shown significant difference yet (PAC: MD =-0.07, 95％CI was -0.18 to 0.04, P = 0.23; PiCCO: MD = 0.09, 95％CI was -0.31 to 0.50, P = 0.65; AA windows: MD =-0.14, 95％CI was -0.31 to 0.02, P = 0.09; PA windows: MD =-0.00, 95％CI was -0.15 to 0.14, P = 0.95; AA/PA windows: MD = 0.23, 95％CI was-0.40 to 0.86, P = 0.47). However, the difference in SV was statistically significant between the USCOM and TD method (MD = 1.48, 95％CI was 0.04 to 2.92, P = 0.04). Funnel chart showed that the literature distribution of CO and CI monitoring were basically symmetrical, indicating that the bias of literature publication is small. Conclusion USCOM has good consistency with TD method in monitoring the cardiac function parameters of CO and CI, and different windows of ultrasonic probe of USCOM have no significant influence on the monitoring results, but there is significant difference in the consistency of the two methods in SV monitoring.

Correlación de gasto cardiaco obtenido por termodilución y por monitor ultrasónico (USCOM) en pacientes con choque séptico / Correlation of cardiac output obtained by termodulution and by ultrasonic monitor in patients with septic shock (USCOM) / Correlação do débito cardíaco obtido pela termodulação e pelo monitor ultrasônico (USCOM) em pacientes com choque septico

Resumen: El catéter en la arteria pulmonar (CAP) es un dispositivo utilizado en unidades de cuidados intensivos (UCI) para medir las presiones en el corazón y los vasos sanguíneos pulmonares como parte del monitoreo hemodinámico, principalmente en pacientes de cirugía cardiaca. El dispositivo USCOM se trata de una técnica no invasiva que utiliza la tecnología Doppler para obtener las medidas de volumen sistólico y sus derivados. Se realiza la siguiente comparación de medición de GC entre estos dos dispositivos en pacientes con choque séptico. Se realizó un estudio tipo observacional, prospectivo, longitudinal y comparativo en pacientes con choque séptico entre 18 y 60 años de edad ingresados en la UTI en el periodo de mayo-junio del 2017. Ante la disminución del uso del catéter de la arteria pulmonar debido a la controversia de no mejorar la mortalidad en los pacientes de las unidades de terapia intensiva (UTI), la colocación de dicho catéter ha caído en desuso; sin embargo, el GC medido por el catéter de Swan-Ganz sigue siendo el «estándar de oro¼ para la medición en tiempo real del GC y las resistencias sistémicas y pulmonares. La medición del GC por CAP versus USCOM se correlaciona de tal forma que puede emplearse en la medición por USCOM en un paciente con choque séptico, al cual no se le pretenda invadir para determinar sus condiciones hemodinámicas.

Abstract: The pulmonary artery catheter (CAP) is a device used in intensive care units (ICUs) to measure pressures in the heart and pulmonary blood vessels as part of hemodynamic monitoring primarily in cardiac surgery patients. The USCOM device is a non-invasive technique that uses Doppler technology to obtain measurements of systolic volume and its derivatives. The following CO measurement comparison is performed between these two devices in patients with septic shock. An observational, prospective, longitudinal and comparative study was conducted in patients with septic shock aged between 18 and 60 years admitted to intensive care in the period May-June 2017. In view of the decrease in the use of the pulmonary artery catheter due to the controversy of not improving the mortality in the patients of the Intensive Care Units, the placement of this catheter has fallen into disuse; however, cardiac output measured by the Swan Ganz catheter remains the «gold standard¼ for real-time measurement of cardiac output and systemic and pulmonary resistance. The CO measurement by PAC versus USCOM correlates, in such a way, that USCOM measurement can be used in a patient with septic shock, who is not expected to invade to determine their hemodynamic conditions.

Resumo: O cateter de artéria pulmonar (CAP) é um dispositivo utilizado em unidades de terapia intensiva (UTI) para medir as pressões nos vasos sanguíneos cardíacos e pulmonares, como parte da monitorização hemodinâmica, principalmente em pacientes submetidos a cirurgia cardíaca. O dispositivo USCOM é uma técnica não invasiva que utiliza a tecnologia Doppler para obter medidas do volume sistólico e seus derivados. A seguinte comparação da medição do DC é feita entre esses dois dispositivos em pacientes com choque séptico. Foi realizado um estudo observacional, prospectivo, longitudinal e comparativo em pacientes com choque séptico com idade entre 18 e 60 anos internados na unidade de terapia intensiva no período de maio a junho de 2017. Dada a diminuição do uso do cateter de artéria pulmonar devido à controvérsia de não melhorar a mortalidade nos pacientes das Unidades de Terapia Intensiva, a colocação do referido cateter caiu em desuso; no entanto, o débito cardíaco medido pelo cateter de Swan Ganz continua sendo o «padrão ouro¼ para a medição em tempo real do débito cardíaco e resistências sistêmicas e pulmonares. A medida do DC por CAP vs USCOM está correlacionada, de tal forma que a medida por USCOM pode ser usada em um paciente com choque séptico, que não se destina a invadir para determinar suas condições hemodinâmicas.

Laboratory analysis on influence of different monitoring modes on related biochemical indicators of early fluid resuscitation in severe sepsis / 国际检验医学杂志

Objective To compare the early fluid resuscitation effect of transpulmonary thermodilution (PICCO) monitoring combined with the passive leg raising (PLR) test and central venous pressure(CVP) mo-nitoring in severe sepsis .Methods Sixty patients with severe sepsis admitted in this hospital from January to December 2016 were selected and divided into the treatment group (n=28) and control group(n=32) accord-ing to the random number table method .The treatment group adopted PICCO monitoring combined with PLR ,while the control group adopted CVP monitoring .The changes of plasma natriuretic peptide (BNP) and blood lactic acid(LAC) levels at 6 ,24 ,48 ,72 h in two groups ,time of vasoactive drugs withdrawn ,mechanical ventilation time ,ICU stay length ,and occurrence situation of multiple organ dysfunction syndrome (MODS) and death were compared between the two groups .Results The plasma BNP levels at 24 ,48 ,72 h in the treat-ment group were lower than those in the control group at the same period ,the difference was statistically sig-nificant(P<0 .05);The plasma LAC levels at 24 ,48 ,72 h in the treatment group were lower than those in the control group at the same periods ,the difference was statistically significant (P<0 .05);The vasoactive drug withdrawal time in the treatment group was faster than that in the control group ,the mechanical ventilation time was shorter than that in the control group ,and the ICU stay time was shorter than that in the control group ,the difference was statistically significant (P<0 .05);The occurrence rates of MODS and death had no statistical difference between the two groups (P>0 .05) .Conclusion The PICCO monitoring combined with PLR in severe sepsis has better early fluid resuscitation curative effect than the CVP monitoring and has im-portant study significance .

Global end‑diastolic volume an emerging preload marker vis‑a‑vis other markers - Have we reached our goal.

A reliable estimation of cardiac preload is helpful in the management of severe circulatory dysfunction. The estimation of cardiac preload has evolved from nuclear angiography, pulmonary artery catheterization to echocardiography, and transpulmonary thermodilution (TPTD). Global end‑diastolic volume (GEDV) is the combined end‑diastolic volumes of all the four cardiac chambers. GEDV has been demonstrated to be a reliable preload marker in comparison with traditionally used pulmonary artery catheter‑derived pressure preload parameters. Recently, a new TPTD system called EV1000™ has been developed and introduced into the expanding field of advanced hemodynamic monitoring. GEDV has emerged as a better preload marker than its previous conventional counterparts. The advantage of it being measured by minimum invasive methods such as PiCCO™ and newly developed EV1000™ system makes it a promising bedside advanced hemodynamic parameter.

The influence of continuous veno-venous hemofiltration on cardiac output value monitored by transpulmonary thermodilution technique in critical patients / 中华危重病急救医学

Objective To investigate the influence of continuous veno-venous hemofiltration (CVVH) on cardiac output (CO) value and parameters of hemodynamics monitored by transpulmonary thermodilution technique in critical patients. Methods A prospective cohort study was conduced. Sixty-two critical patients admitted to intensive care unit (ICU) of Zunyi Medical College Affiliated Hospital from January 2011 to October 2015 were enrolled. All of the patients received CVVH through femoral vein puncture catheter. The CO value was monitored before CVVH operation, immediately after CVVH operation (8 ℃ normal saline was injected immediately after the output of blood from the arterial end), 5 minutes after operation, the time at the sudden interruption (press pause key after 10 minutes of operation) and resumed immediately, 15 minutes and 30 minutes after operation by pulse-indicated continuous cardiac output (PiCCO) with transpulmonary thermodilution method. The changes in heart rate (HR), mean arterial pressure (MAP), central venous pressure (CVP), and blood temperature were observed at all time points. Results From CVVH before start to 5 minutes thereafter, CO values were not significantly changed in patients, fluctuating in 6.96 (7.33, 8.67)-6.98 (6.43, 7.45) L/min. When CVVH was suddenly interrupted, CO value was immediately increased to the peak 8.04 (7.36, 8.77) L/min, which showed statistically significant difference as compared with other time points (all P < 0.01). Immediately after the CVVH recovery from interruption, the CO value dropped to 4.71 (4.14, 7.26) L/min, and it was significantly lower than those at other time points (all P < 0.01). With the CVVH recovery, the patients' CO value was gradually restored to the stable operation ahead of interruption [4.71 (4.14, 7.26)-6.85 (6.08, 7.26) L/min]. During CO monitoring, HR, MAP, CVP and blood temperature of the patients were at the same level, and no significant changes were founded. Conclusions CVVH interruption of immediate PiCCO monitoring CO value were significantly increased, immediately after the CVVH recovery the CO value were significantly reduced, and the normal operation of CVVH did not affect the CO value monitoring. Hemodynamics and blood temperature of all patients were stable during CVVH.

The influence of continuous venovenous hemofiltration on parameter measurement by the transpulmonary thermodilution technique / 中华危重病急救医学

ObjectiveTo evaluate the influence of continuous venovenous hemofiltration (CVVH) on measurement of transpulmonary thermodilution parameters.MethodsA prospective observational study was conducted. Fifty-six patients who received CVVH and hemodynamic monitoring at the same time admitted to the Department of Critical Care Medicine of Tianjin Third Central Hospital from July 2012 to July 2014 were enrolled. In all the patients, the dialysis catheter was inserted through the femoral vein, and transpulmonary thermodilution measurements were performed by pulse indicator continuous cardiac output (PiCCO) monitoring technology at the same time. Mean arterial pressure (MAP), central blood temperature, cardiac index (CI), global end-diastolic volume index (GEDVI), intrathoracic blood volume index (ITBVI) and extravascular lung water index (EVLWI) were measured before CVVH, immediately after CVVH, and 30 minutes after CVVH, respectively.Results In the 56 patients, there were 36 males and 20 females, (66±16) years of old, height of (172±6) cm, body weight of (68±10) kg. The acute physiology and chronic health evaluationⅡ (APACHEⅡ) scores was 26±6. After CVVH,the central blood temperature was gradually decreased, and blood temperature at 30 minutes after CVVH was significantly lower than that before CVVH (℃: 37.17±1.06 vs. 37.57±1.26,P 0.05]. CI, GEDVI, ITBVI at 30 minutes after CVVH were significantly decreased [CI (mL·s-1·m-2): 57.84±20.50 vs. 63.85±21.84, GEDVI (mL/m2):681±106 vs. 727±100, ITBVI (mL/m2): 851±133 vs. 908±125, allP< 0.05]. CVVH was associated with a decline of 6.01 mL·s-1·m-2 at 30 minutes after CVVH [95% confidence interval (95%CI) = -10.67 to -1.50,P = 0.011]. The declines of GEDVI and ITBVI were observed with 46 mL/m2 (95%CI = -81 to - 11,P = 0.014), 57 mL/m2 (95%CI =-101 to - 13,P = 0.014 ) respectively 30 minutes after CVVH.Conclusions CVVH had no significant effect on the transpulmonary thermodilution measurements of CI, GEDVI, ITBVI and EVLWI. Thirty minutes after the start of CVVH, CI, GEDVI and ITBVI was decreased significantly, but had no effect on EVLWI.

Recent trend in cardiac output monitoring and trans-cardiopulmonary thermodilution-derived hemodynamic parameters

Currently, hemodynamic monitoring system is developing rapidly, with many different devices now available, which makes anesthesiologists feel somewhat confused by the various possibilities and issue of noninvasiveness. By the order of degree of invasiveness, these devices can be classified into the highly invasive pulmonary artery catheter and the completely noninvasive bioimpedance/bioreactance technique and Doppler echocardiography. Recently, trans-cardiopulmonary thermodilution-derived hemodynamic parameters, such as global end-diastolic volume, global ejection fraction, cardiac function index, extravascular lung water, pulmonary vascular permeability index and its cardiac output, are available in anesthetic practice by PiCCO(R)(Pulsion Medical Systems) and VolumeView(R) (Edwards Life Sciences). This article provides objective review of the monitoring systems, as well as the advantages and limitations, in order to offer better management of the critically ill patients undergoing surgery.

Transpulmonary thermodilution for evaluating respiratory function in swine after severe acute dichlorvos poisoning / 中华急诊医学杂志

Objective In order to extrapolate the respiratory dysfunction of patients in early stage of acute organophosphorus pesticide poisoning (AOPP),transpulmonary thermodilution technique was used in swine models of severe acute dichlorvos poisoning (SADP) to evaluate respiratory function.Methods Twenty healthy female swine were randomly divided into dichlorvos ( n =7 ),atropine ( n =7 ) and control (n =6) groups.In the dichlorvos group,the swine were administered with 80％ emulsified dichlorvos (100mg/kg) via the gastric tube toinduce SADP.In the atropine group,swinewere administered with dichlorvos,and 0.5h later,atropine was injected to obtain and maintain atropinization.The swine of control group were administered with saline solution instead.Arterial and venous blood samples were collected 0,0.5,1,2,4 and 6 hours after modeling for blood gas analysis and detecting acetylcholinesterase levels.Both extravascular lung water index (EVLWI) and pulmonary vascular permeability index ( PVPI ) were measured by using PiCCO (pulse indicator continuous cardiac output ). At the termination of the experiment,the animals were sacrificed and the lung wet/dry weight ratio was determined and histopathological changes of lung tissue were also observed under microscope.Results In the dichlorvos group,EVLWI and PVPI were substantially increased from 0.5 h to 6 h after modeling but PaO2/FiO2 decreased from 0-6 h after modeling.In the atropine group,EVLWI and PVPI increased initially,but then they decreased 1 h afterwards and PaO2/FiO2 was also gradually decreased from 0-1 h.In both dichlorvos group and atropine group,the EVLWI was negatively correlated with PO2/FiO2 and positively correlated with PVPI.Compared with the control group,the lung wet/dry weight ratio increased markedly in the dichlorvos group and mildly increased in the atropine group.Meanwhile,the histopathological changes of lung tissue were obvious in the dichlorvos group and mild in the atropine group.Conclusions SADP swine experienced substantial changes in respiratory function. EVLWI was a reliable and valuable indicator for evaluating respiratory function in the early stage of AOPP.

Comparison of transthoracic electrical bioimpedance cardiac output measurement with thermodilution method in post coronary artery bypass graft patients.

Transthoracic electrical bioimpedance (TEB) has been proposed as a non-invasive, continuous, and cost-effective method of cardiac output (CO) measurement. In this prospective, non-randomized, clinical study, we measured CO with NICOMON (Larsen and Toubro Ltd., Mysore, India) and compared it with thermodilution (TD) method in patients after off-pump coronary artery bypass (OPCAB) graft surgery. We also evaluated the effect of ventilation (mechanical and spontaneous) on the measurement of CO by the two methods. Forty-six post-OPCAB patients were studied at five predefined time points during controlled ventilation and at five time points when breathing spontaneously. A total of 230 data pairs of CO were obtained. During controlled ventilation, TD CO values ranged from 2.29 to 6.74 L/min (mean 4.45 ± 0.85 L/min), while TEB CO values ranged from 1.70 to 6.90 L/min (mean 4.43 ± 0.94 L/min). The average correlation (r) was 0.548 (P = 0.0002), accompanied by a bias of 0.015 L/min and precision of 0.859 L/min. In spontaneously breathing patients, TD CO values ranged from 2.66 to 6.92 L/min (mean 4.66 ± 0.76 L/min), while TEB CO values ranged from 3.08 to 6.90 L/min (mean 4.72 ± 0.82 L/min). Their average correlation was relatively poor (r = 0.469, P= 0.002), accompanied by a bias of −0.059 L/min and precision of 0.818 L/min. The overall percent errors between TD CO and TEB CO were 19.3% (during controlled ventilation) and 17.4% (during spontaneous breathing), respectively. To conclude, a fair correlation was found between TD CO and TEB CO measurements among post-OPCAB patients during controlled ventilation. However, the correlation was weak in spontaneously breathing patients.

Is radial artery pressure waveform derived cardiac index is reliable during cardiac surgery with hypothermic cardiopulmonary bypass? / 대한마취과학회지

BACKGROUND: Discrepancy of central-peripheral arterial pressure after cardiopulmonary bypass may affect the reliability of arterial pressure waveform derived cardiac index (APCI) monitoring. METHODS: In 15 elective cardiac surgeries employing moderate hypothermic cardiopulmonary bypass (CPB), APCI from radial arterial cannula and pulmonary artery catheter derived cardiac index from thermodilution method (PACI) were measured 1) after anesthesia induction (T1), 2) before CPB (T2), 3) immediately after CPB (T3) and 4) 1 hour after CPB (T4). APCI and PACI were analyzed by using the Bland-Altman analysis. RESULTS: Biases of APCI and PACI at T1, T2, T3 and T4 were 0.093 L/min/m2, -0.053 L/min/m2, 0.485 L/min/m2 and -0.09 L/min/m2, respectively. The limits of agreement (2 SD) at T1, T2, T3 and T4 were from -2.285 to 2.471 L/min/m2, -2.475 to 2.369 L/min/m2, -2.255 to 3.225 L/min/m2 and -2.609 to 2.423 L/min/m2, respectively. Bias of APCI and PACI during entire period (T1-T4) was 0.095 L/min/m2 and 2 SD was from -2.387 to 2.557 L/min/m2. However, mean error % (2 SD/mean) of APCI at T1, T2, T3, and T4 were greater than 30%. CONCLUSIONS: Our results were not able to show that APCI measured from radial artery is comparable to PACI for hemodynamic monitoring during cardiac surgery employing moderate hypothermic CPB. Considering the limitations of PACI as a gold standard of hemodynamic monitoring in a certain clinical circumstance, further investigation employing other monitoring method than PACI may be followed to get more definitive conclusion.

Modelflow method versus continuous thermodilution technique for cardiac output measurement in liver transplant patients / 대한마취과학회지

BACKGROUND: In critically ill patients, cardiac output (CO) is used as a parameter for assessing hemodynamic status and efficacy of treatment. Continuous CO (CCO) could facilitate this assessment during general anesthesia. A new method of arterial pulse wave analysis has been introduced, which estimates beat to beat CO from arterial pressure via Modelflow. It remains uncertain how well this method performs in high output states. We analyzed the relationship between CCO and Modelflow computed from radial and femoral pressures (MFCO(RA), MFCO(FA)) during liver transplantation (LT). METHODS: Measurements were performed in 100 liver transplant patients. Groups A had 36 patients, and group C had 64 patients with both groups composed of Child-Turcotte A, B and C patients Eighty patients had CCO 10 L/min (group E) during anhepatic phase. RESULTS: CCO ranged from 5.0 to 15.4 L/min (MFCO(RA) 3.2 to 10.7 L/min, MFCO(FA) 4.3 to 11.8 L/min). Bland-Altman analyses showed the limit of agreement of MFCO(RA) (-1.5 to 5.2, bias = 1.9 L/min) and of MFCO(FA) (-2.6 to 4.4, bias = 0.9 L/min). CO measured by the two methods was significantly different in groups, except for MFCO(FA) in group C. In group D, bias was 1.5 L/min (SD 1.3 L/min) for MFCO(RA) and 0.9 L/min for MFCO(FA) (SD 1.4 L/min). In group E, biases of 3.5 L/min and 2.4 L/min were obtained for MFCO(RA) and MFCO(FA), respectively. CONCLUSIONS: These results suggest that the group-average value of MFCO is not an accurate parameter for estimating CO during LT, with the exception of MFCO(FA) in groups C and D.

Problems in Cardiac Output Measurement and Clinical Understanding / 대한마취과학회지

Cardiac output measurement is so important that it is widely used in anesthesia and intensive care practice.However, the basic principles for the measurement of each device are not taught for clinicians.This review article describes considerable points for each device; 1) temperature sensors and integration problem for pulmonary artery catheter, 2) angle of ultrasonic probe and meaning of turbulent flow for transesophageal echocardiography, 3) angle of ultrasonic probe and meaning of pulsatile laminar flow for CarioQ, 4) end-tidal and arterial carbon dioxide concentration for Noninvasive cardiac output, 5) the concept of convolution for the arterial pulse wave and arterial resistance for Vigileo, and 6) effect size as a statistical viewpoint of comparison in device effectiveness.As a clinician we should not interpret the value of cardiac output as an absolute meaning, but do as a relative trend considering these theoretical errors.