Hemolysis and inflammatory response to extracorporeal circulation during on-pump cabg: comparison between roller and centrifugal pump systems

Abstract Objective: To compare the perioperative incidence rates of hemolysis and inflammatory response in patients undergoing coronary artery bypass grafting with the two main types of cardiopulmonary bypass, centrifugal and roller pumps, and establish correlations among hemolytic and inflammatory changes. Methods: This was a prospective, randomized trial of 60 patients assigned to either roller pump (G1, n=30) or centrifugal pump (G2, n=30) bypass. Markers of hemolysis (serum haptoglobin, lactate dehydrogenase [LDH]) and inflammation (interleukin [IL]1ß, IL-6, and TNF-α) were measured and analyzed. Results: There was no significant between-group difference in the variables of interest. In G1, there was a positive association with IL-6 and TNF-α (P<0.01 and P<0.05, respectively). In G2, there was a positive association with LDH in the postoperative period (P<0.5). At 24h post-cardiopulmonary bypass, there were positive associations between LDH and IL-1ß (P<0.05), LDH and TNF-α (P<0.01), haptoglobin and TNF-α (P<0.05), and LDH and TNF-α (P<0.01) in G1, and between LDH and IL-6 (P<0.01), LDH and TNF-α (P<0.01), and LDH and IL-6 (P<0.01) in G2. Conclusion: There were no significant between-group differences in markers of hemolysis or inflammation. IL-6 and TNF-α were positively associated with duration of cardiopulmonary bypass in G1, while LDH was positively associated with duration of cardiopulmonary bypass in G2. The rate of significant associations between markers of hemolysis and inflammation was higher in the roller pump group (G1). Registration number: ReBEC (RBR-92b9dg).

Diagnostic evaluation of risk for bleeding in cardiac surgery with extracorporeal circulation / Avaliação diagnóstica do risco de sangramento em cirurgia cardíaca com circulação extracorpórea / Evaluación diagnóstica del riesgo de hemorragia en cirugía cardíaca con circulación extracorpórea

ABSTRACT Objective: to identify the risk factors associated with cases of excessive bleeding in patients submitted to cardiac surgery with extracorporeal circulation. Method: case-control study on the factors of risk for bleeding based on the analysis of data from the medical charts of 216 patients submitted to cardiac surgery with elective extracorporeal circulation during a three-year period. Results: variables that are commonly associated with excessive bleeding in studies in the field were analyzed, and the following were considered as risk factors for the nursing diagnosis "risk for bleeding" (00206) in cardiac surgery with extracorporeal circulation: Body mass index lower than 26.35kg/m² (Odds ratio = 3.64); Extracorporeal circulation longer than 90 minutes (Odds ratio = 3.57); Hypothermia lower than 32°C (Odds ratio = 2.86); Metabolic acidosis (Odds ratio = 3.50) and Activated partial thromboplastin time longer than 40 seconds (Odds ratio= 2.55). Conclusion: such variables may be clinical indicators of an operational nature for a better characterization of the risk factor "treatment regimen" and a refinement of knowledge related to coagulopathy induced by extracorporeal circulation, which is currently presumably incorporated into the "treatment regimen" category of the nursing diagnostic classification by NANDA International, Inc.

RESUMO Objetivo: identificar os fatores de risco associados aos casos de sangramento excessivo em pacientes submetidos à cirurgia cardíaca com circulação extracorpórea. Método: estudo de caso-controle dos fatores de risco de sangramento com análise de dados de prontuários de 216 pacientes submetidos à cirurgia cardíaca com circulação extracorpórea de caráter eletivo durante o período de três anos. Resultados: foram analisadas variáveis comumente associadas ao sangramento excessivo em estudos na área, sendo considerados como fatores de risco para o diagnóstico de enfermagem "risco de sangramento" (00206) em cirurgia cardíaca com circulação extracorpórea: Índice de massa corporal menor que 26,35kg/m² (Odds ratio = 3,64); Circulação extracorpórea maior que 90 minutos (Odds ratio = 3,57); Hipotermia menor que 32°C (Odds ratio = 2,86); Acidose metabólica (Odds ratio = 3,50) e Tempo de tromboplastina parcial ativada maior que 40 segundos (Odds ratio = 2,55). Conclusão: tais variáveis podem ser indicadores clínicos de natureza operacional para melhor caracterização do fator de risco "regime de tratamento" e de um refinamento do conhecimento relacionado à coagulopatia induzida pela circulação extracorpórea, provavelmente hoje incorporada na categoria de "regime de tratamento" da classificação diagnóstica de enfermagem da NANDA International, Inc.

RESUMEN Objetivo: identificar los factores de riesgo asociados a casos de hemorragia excesiva en pacientes sometidos a cirugía cardíaca con circulación extracorpórea. Método: estudio de caso control de los factores de riesgo de hemorragia con análisis de datos de fichas médicas de 216 pacientes, sometidos a cirugía cardíaca, con circulación extracorpórea, de carácter electivo durante el período de tres años. Resultados: fueron analizadas variables comúnmente asociadas a hemorragia excesiva, en estudios en esta área, siendo considerados como factores de riesgo para el diagnóstico de enfermería "riesgo de hemorragia" (00206) en cirugía cardíaca con circulación extracorpórea, los siguientes: Índice de masa corporal <26,35 Kg/m² (Odds ratio= 3,64); Circulación extracorpórea mayor que 90 minutos (Odds ratio = 3,57); Hipotermia menor que 32°C (Odds ratio = 2,86); Acidosis metabólica (Odds ratio = 3,50); y Tiempo de tromboplastina parcial activada mayor que 40 segundos (Odds ratio = 2,55). Conclusión: esas variables pueden ser indicadores clínicos de naturaleza operacional para caracterizar mejor el factor de riesgo "régimen de tratamiento" y para perfeccionar el conocimiento relacionado a la coagulopatía inducida por la circulación extracorpórea; probablemente, actualmente incorporada a la categoría de "régimen de tratamiento" de la clasificación diagnóstica de enfermería de la NANDA International Inc.

Relationship between high red cell distribution width and systemic inflammatory response syndrome after extracorporeal circulation

Abstract Objective: Cardiac surgical operations involving extracorporeal circulation may develop severe inflammatory response. This severe inflammatory response syndrome (SIRS) is usually associated with poor outcome with no predictive marker. Red cell distribution width (RDW) is a routine hematological marker with a role in inflammation. We aim to determine the relationship between RDW and SIRS through our study. Methods: A total of 1250 patients who underwent cardiac surgery with extracorporeal circulation were retrospectively analyzed out of which 26 fell into the SIRS criteria and 26 consecutive control patients were taken. RDW, preoperative clinical data, operative time and postoperative data were compared between SIRS and control groups. Results: The demographic profile of the patients was similar. RDW was significantly higher in the SIRS versus control group (15.5±2.0 vs. 13.03±1.90), respectively with P value <0.0001. There was significant mortality in the SIRS group, 20 (76.92%) as compared to 2 (7.6%) in control group with a P value of <0.005. Multiple logistic regression analysis revealed that there was significant association with high RDW and development of SIRS after extracorporeal circulation (OR for RDW levels exceeding 13.5%; 95% CI 1.0-1.2; P<0.05). Conclusion: Increased RDW was significantly associated with increased risk of SIRS after extracorporeal circulation. Thus, RDW can act as a useful tool to predict SIRS in patients undergoing cardiac surgery with extracorporeal circulation. Hence, more aggressive measures can be taken in patients with high RDW to prevent postoperative morbidity and mortality.

Oxigenoterapia hiperbárica no acidente aeroembólico no pós-operatóriode cirurgia cardíaca / Hyperbaric oxygen therapy for treating an aeroembolic accident after heart surgery

A embolia aérea sistêmica pode ter várias etiologias. Durante a circulação extracorpórea (CEC) é estimadaem 0,1 %, entretanto a grande maioria das intercorrências não é relatada ou é imperceptível, dependendo do grau de comprometimento neurológico e do tempo em que ocorreu após a cirurgia. Em geral, a embolia aérea pode causar distúrbios cognitivos, danos focais, coma e morte. O presente trabalho relataa experiência do Instituto Estadual de Cardiologia Aloysio de Castro com acidentes semelhantes no pósoperatório,que foram tratados com oxigenoterapiahiperbárica, com recuperação total.

Estimated at 0.1% during extracorporeal circulation, systemic air embolisms may have different etiologies. However, the vast majority ofcomplications are not reported or are imperceptible, depending on neurological involvement and the length of time after surgery. In general, air embolisms may cause cognitive disorders, focal damage, coma and death. This paper reports on the experience of the Aloysio de Castro State Cardiology Institute, treating these accidents during the postoperativeperiod with hyperbaric oxygen therapy,with full recovery.

Hemólise na circulação extracorpórea: correlação com tempo e procedimentos realizados / Hemolysis in extracorporeal circulation: relationship between time and procedures

INTRODUÇÃO: A circulação extracorpórea (CEC) é indispensável para a maioria das operações cardíacas, mas causa danos significantes ao sangue, dentre eles a hemólise. OBJETIVO: Quantificar as taxas de hemólise em diferentes tempos nas operações para revascularização do miocárdio com uso de CEC. MÉTODOS: Foram medidas as taxas de hemólise de 22 pacientes em 6 tempos distintos durante a revascularização do miocárdio com uso de CEC: T0 - antes do início da CEC, T1 - 5 minutos após o início da CEC, T2 - com 30 minutos de CEC, T3 - imediatamente antes do despinçamento da aorta, T4 - imediatamente antes da passagem do volume residual para o paciente e T5 - 5 minutos após o término da passagem do volume residual para o paciente. Foram calculadas as taxas de hemólise entre os intervalos de tempo: T0-T1; T1-T2; T2-T3; T3-T4 e T4-T5. RESULTADOS: Os primeiros 5 minutos após a CEC demonstraram maior taxa de hemólise (P = 0,0003) em comparação às outras taxas calculadas, representando 29% da hemólise total até T4 (imediatamente antes da passagem do volume residual para o paciente). CONCLUSÃO: Não foram observadas variações significantes nas taxas de hemólise durante a aspiração na raiz da aorta (P > 0,38) nem com o procedimento utilizado para a passagem do volume residual de sangue no circuito para os pacientes.

INTRODUCTION: Extracorporeal circulation (EC) is very important in cardiac surgery but causes significant damage to the blood, including hemolysis. OBJECTIVE: To quantify the rate of hemolysis at different times during EC in elective coronary artery bypass grafting. METHODS: We measured rates of hemolysis of 22 patients at 6 different times during myocardial revascularization during EC: T0 - before the start of EC, T1 - five minutes after of the EC initiation, T2 - 30 minutes of EC, T3 - immediately before the aortic unclamping, T4 - immediately before passage of the residual volume to the patient and T5 - five minutes after the passage of the residual volume to the patient. Rates of hemolysis were calculated between the intervals of time: T0-T1; T1-T2; T2-T3; T3-T4 and T4-T5. RESULTS: The first 5 minutes after the EC showed the highest rate of hemolysis (P = 0.0003) compared to the others calculated rates, representing 29% of the total haemolysis until T4 (Immediately before passage of the residual volume to the patient). CONCLUSION: There were no significant changes in the rate of hemolysis during the suction in the aortic root (P> 0.38), nor with the procedure used for the passage of the residual volume of blood in the circuit to the patient.

Intervenciones para conservar la sangre en cirugía cardíaca con circulación extracorpórea / Interventions for preserving blood in cardiac surgery with cardiopulmonary bypass)", "_i": "

El paciente que es sometido a cirugía con circulación extracorpórea desarrolla alteraciones hemostáticas causadas por la exposición de sangre a superficies no endoteliales, por la anticoagulación administrada y por la hemodilución secundaria al cebado del circuito extracorpóreo con soluciones no sanguíneas; lo que aumenta el número de transfusiones sanguíneas y el riesgo de complicaciones. Para disminuirlas, actualmente existen múltiples estrategias. El presente trabajo tiene como objetivo dar a conocer las intervenciones basadas en evidencia científica para conservar la sangre en pacientes sometidos a cirugía cardíaca con circulación extracorpórea en la etapa perioperatoria.

The patient who is subjected to cardiopulmonary bypass develops alters the hemostatic system because of the blood exposure to the synthetic surfaces of the CPB circuit, the anticoagulation and the secondary hemodilution with the prime solution. All of these factors raise the blood transfusions and the complications. Now a day, there are a lot of strategies to decrease these complications. In this study it reviewed the preoperative procedures to avoid these complications in the patients that need a cardiac surgery using the cardiopulmonary bypass.

Oxidative stress and inflammatory response increase during coronary artery bypass grafting with extracorporeal circulation / Estresse oxidativo e resposta inflamatória aumentam durante cirurgia de revascularização miocárdica com circulação extracorpórea

INTRODUCTION: Thiobarbituric acid-reactive substance is a marker of oxidative stress and has cytotoxic and genotoxic actions. C- reactive protein is used to evaluate the acute phase of inflammatory response. OBJECTIVES: To assess the thiobarbituric acid-reactive substance and C-reactive protein levels during extracorporeal circulation in patients submitted to cardiopulmonary bypass. METHODS: Twenty-five consecutive surgical patients (16 men and nine women; mean age 61.2 ± 9.7 years) with severe coronary artery disease diagnosed by angiography scheduled for myocardial revascularization surgery with extracorporeal circulation were selected. Blood samples were collected immediately before initializing extracorporeal circulation, T0; in 10 minutes, T10; and in 30 minutes, T30. RESULTS: The thiobarbituric acid-reactive substance levels increased after extracorporeal circulation (P=0.001), with average values in T0=1.5 ± 0.07; in T10=5.54 ± 0.35; and in T30=3.36 ± 0.29 mmoles/mg of serum protein. The C-reactive protein levels in T0 were negative in all samples; in T10 average was 0.96 ± 0.7 mg/dl; and in T30 average was 0.99 ± 0.76 mg/dl. There were no significant differences between the dosages in T10 and T30 (P=0.83). CONCLUSIONS: C-reactive protein and thiobarbituric acid-reactive substance plasma levels progressively increased during extracorporeal circulation, with maximum values of thiobarbituric acid-reactive substance at 10 min and of Creactive protein at 30 min. It suggests that there are an inflammatory response and oxidative stress during extracorporeal circulation.

INTRODUÇÃO: Substâncias reativas do ácido tiobarbitúrico são um marcador de estresse oxidativo. A proteína C reativa é usada para avaliar a fase aguda da resposta inflamatória. OBJETIVOS: Avaliar os níveis de substâncias reativas do ácido tiobarbitúrico e da proteína C reativa durante a circulação extracorpórea em pacientes submetidos à cirurgia de revascularização miocárdica. MÉTODOS: Vinte e cinco pacientes consecutivos (16 homens e nove mulheres com idade média de 61,2 ± 9,7 anos) com doença arterial coronária severa diagnosticada por angiografia, escalados para cirurgia de revascularização miocárdica com circulação extracorpórea, foram selecionados. Amostras sanguíneas foram coletadas imediatamente antes de iniciar a circulação extracorpórea (T0), 10 minutos após (T10) e 30 minutos após (T30). RESULTADOS: Os níveis de substâncias reativas do ácido tiobarbitúrico aumentaram após a extracorpórea (P=0,001) com valores médios de 1,5 ± 0,07 em T0; 5,54 ± 0,35 em T10 e 3,36 ± 0,29 mmoles/mg de proteína sérica em T30. Os níveis de proteína C reativa foram negativos em T0 em todas as amostras. Em T10, os valores médios foram de 0,96 ± 0,7 mg/dl e em T30 os valores médios foram de 0,99 ± 0,76 mg/ dl. Não houve diferença significativa entre os valores de proteína C reativa nos tempos T10 e T30 (P= 0,83). CONCLUSÕES: Os níveis de substâncias reativas do ácido tiobarbitúrico e da proteína C reativa aumentam durante a circulação extracorpórea, com máximos valores de substâncias reativas do ácido tiobarbitúrico em 10 minutos e de proteína C reativa em 30 minutos. Estes achados sugerem resposta inflamatória e estresse oxidativo durante a circulação extracorpórea.

Influencia de algunos factores de riesgo cardiovasculares sobre los eventos clínicos adversos más frecuentes, en pacientes revascularizados con circulación extracorpórea / Influences of some cardiovascular risk factors on the more frequent adverse clinical events in revascularization patients with extracorporeal circulation

Objetivo: determinar cómo influyen diferentes factores de riesgo, sobre los eventos clínicos adversos más frecuentes en el posoperatorio inmediato de los pacientes tratados con cirugía de revascularización miocárdica con circulación extracorpórea. Métodos: se realizó un estudio observacional, longitudinal y prospectivo en 60 pacientes del Instituto de Cardiología y Cirugía Cardiovascular, durante el período 2008-2009. Resultados: se observó, un predominio de pacientes dislipidémicos (90 por ciento) e hipertensos (86,7 por ciento). Los pacientes con manifestación de eventos clínicos adversos demostraron una estrecha asociación con la dislipidemia (p< 0,01), una disminución significativa de la fracción de eyección del ventrículo izquierdo (p< 0,05), un aumento significativo de los tiempos de circulación extracorpórea (p< 0,01), y paro isquémico (p< 0,05). Conclusiones: la dislipidemia basal, la fracción de eyección del ventrículo izquierdo deprimida y la prolongación del proceder quirúrgico, fueron los factores de riesgo más significativos para el desarrollo de eventos clínicos adversos, en el posoperatorio inmediato de los pacientes revascularizados(AU)

Objective: to determine how different risk factors influence on the more frequent adverse clinical events during the immediate postoperative period of patients operated on myocardial revascularization surgery with extracorporeal circulation. Methods: a prospective, longitudinal and observational study was conducted in 60 patients from the Institute of Cardiology and Cardiovascular Surgery for 2008-2009. Results: there was predominance of dyslipemia patients (90 percent) and hypertensive patients (86.7 percent). Patients with manifestation of adverse clinical events showed a close association with dyslipemia (p< 0.01), a significant decrease of ejection fraction of left ventricle (p< 0.05), a significant increase of extracorporeal circulation times (p < 0.01) and ischemic arrest (p< 0.05). Conclusions: the basal dyslipemia, the depressed left ventricle ejection and the length of surgical procedure, were the more significant risk factors for development of adverse clinical events during the immediate postoperative period of revascularization patients(AU)

Glicemia perioperatória e complicações pós-operatórias em cirurgia cardíaca pediátrica / Perioperative blood glucose level and postoperative complications in pediatric cardiac surgery

FUNDAMENTO: Anestesia para cirurgia cardíaca pediátrica é sistematicamente realizada em pacientes graves sob condições fisiológicas anormais. No intraoperatório, existem variações significativas da volemia, temperatura corporal, composição plasmática e fluxo sanguíneo tecidual, além de ativação da inflamação, com consequências importantes. Medidas seriadas da glicemia podem indicar estados de exacerbação da resposta neuroendocrinometabólica ao trauma servindo como marcadores prognóstico de morbidade nessa população. OBJETIVO: Correlacionar os níveis de glicemia do período perioperatório de crianças submetidas a cirurgia cardíaca com a ocorrência de complicações no pós-operatório e comparar os níveis intraoperatórios de glicemia de acordo com as condições perioperatórias. MÉTODOS: Informações referentes ao procedimento anestésico-cirúrgico e condições perioperatórias dos pacientes foram coletadas em prontuário. Comparações das médias dos valores perioperatórios da glicemia nos grupos de pacientes que apresentaram, ou não, complicações pós-operatórias e as frequências referentes às condições perioperatórias foram estabelecidas conforme cálculo da razão de chances e em análises univariáveis não paramétricas. RESULTADOS: Valores mais elevados de glicemia intraoperatória foram observados nos indivíduos que apresentaram complicações pós-operatórias. Prematuridade, faixa etária, tipo de anestesia e caráter do procedimento não apresentaram influência na média glicêmica do intraoperatório. O emprego de Circulação Extracorpórea (CEC) esteve associado a maiores valores de glicemia durante a cirurgia. Nos procedimentos com CEC, maiores níveis glicêmicos foram observados nos indivíduos que evoluíram com infecção e complicações cardiovasculares, nas cirurgias sem CEC essa mesma associação ocorreu com complicações infecciosas e hematológicas. CONCLUSÃO: Níveis intraoperatórios mais elevados de glicemia estão associados com maior morbidade no pós-operatório de cirurgia cardíaca pediátrica.

BACKGROUND: Anesthesia for pediatric cardiac surgery is systematically performed in severely ill patients under abnormal physiological conditions. In the intraoperative period, there are significant variations in blood volume, body temperature, plasma composition, and tissue blood flow, in addition to activation of inflammation, with important consequences. Serial measurements of blood glucose levels can indicate states of exacerbation of the neuroendocrine-metabolic response to trauma, serving as prognostic markers of morbidity in that population. OBJECTIVE: To correlate perioperative blood glucose levels of children undergoing cardiac surgery with the occurrence of postoperative complications, and to compare intraoperative blood glucose levels according to perioperative conditions. METHODS: Information regarding the surgical/anesthetic procedure and perioperative conditions of patients was collected from the medical records. The mean perioperative blood glucose levels in the groups of patients with and without postoperative complications and the frequencies of perioperative conditions were compared by use of odds ratio and non-parametric univariate analyses. RESULTS: Higher intraoperative blood glucose levels were observed in individuals who had postoperative complications. Prematurity, age group, type of anesthesia, and character of the procedure did not influence the mean intraoperative blood glucose level. The use of extracorporeal circulation (ECC) was associated with higher blood glucose levels during surgery. In procedures with ECC, higher blood glucose levels were observed in individuals who had infectious and cardiovascular complications. In surgeries without ECC, that association was observed with infectious and hematological complications. CONCLUSION: Higher intraoperative blood glucose levels are associated with higher morbidity in the postoperative period of pediatric cardiac surgery.

Proteína C reactiva de alta sensibilidad como predictor de fibrilación auricular postoperatoria / High-sensitivity C-reactive protein predicts postoperative atrial fibrillation

Introducción: La fibrilación auricular postoperatoria (FAPO) es una complicación frecuente en la cardiocirugía con circulación extracorpórea (CEC). El evento de isquemia-reperfusión secundario a la CEC produce inflamación como mediador de daño miocárdico causando FAPO. Objetivo: determinar el poder predictivo del marcador de inflamación proteína C reactiva de alta sensibilidad (hsCRP) en la FAPO. Hipótesis: la hsCRP predice la ocurrencia de FAPO. Material y Método: estudio observacional, analítico, incluyó 123 pacientes sometidos a cardiocirugía con CEC en el Hospital Clínico de la Universidad de Chile entre 2007 y 2010. El muestreo fue aleatorio simple de pacientes concurrentes a cirugía cardíaca. Se realizó monitoreo electrocardiográfico continuo y medición de hsCRP plasmática antes de la cirugía, 8 horas postoperatorias y al alta. Se realizó un análisis de regresión multivariada, considerando los factores de riesgo conocidos de FAPO, así como la hsCRP. Para variable cuantitativa continua, se realizó ANOVA-Bonferroni. Para análisis de Kaplan-Meier de cuartiles de hsCRP, se realizó test de tendencia log-rank. Se realizó una receiver operator curve (ROC) para determinar el poder predictivo de la hsCRP. Significancia: p<0,05. Resultados: Se describe el perfil clínico-epidemiológico de los pacientes. La hsCRP fue máxima a las 8 horas postoperatorias (ANOVA-Bonferroni p<0,01). El análisis de regresión multivariada relacionó significativamente hsCRP y ocurrencia de FAPO (p<0,01). A mayor cuartil de hsCRP se asoció mayor ocurrencia de FAPO (p<0,01). El área bajo la curva ROC fue 0,73. Discusión: La hsCRP postoperatoria constituye una valiosa herramienta predictora de ocurrencia de FAPO en el contexto de cirugía cardíaca con CEC.

Introduction: Postoperative atrial fibrillation (POAF) is a common complication of cardiac surgery with extracorporeal circulation. Is associated with increased morbidity and health costs. The ischemia-reperfusion event secondary to extracorporeal circulation leads to inflammation, causing myocardial damage. Objective: The aim of this study is to determine the predictive power of high sensitivity C-reactive protein (hsCRP) in POAF.Hypothesis: hsCPR predicts POAF occurrence. Material and Method: An observational, analytical study, included 123 patients undergoing cardiac surgery with extracorporeal circulation at Universidad de Chile’s Hospital, between 2007 and 2010. Continuous electrocardiographic monitoring was performed and plasma hsCPR measurement before surgery, 8 hours postoperatively and at discharge. We performed a multivariate regressionanalysis considering the known risk factors for POAF and the hsCRP. For continuous quantitative variable ANOVA-Bonferroni was used. Kaplan-Meier analysis of quartiles of hsPCR was usedand Mantel-Cox log-rank test for trend test. Receiver operator curve (ROC) was performed to determine the predictive power of the hsPCR. Significance: p<0.05. Results: We describe the clinical and epidemiological characteristics of patients undergoingcardiac surgery. The hsCPR was highest at 8 postoperative hours (ANOVA-Bonferroni p<0.01). The multivariate regression analysis significantly correlated with the occurrence of hsPCRand POAF (p<0.01). The higher quartile of hsCPR was associated with increased occurrence of POAF (p<0.01). The area under the ROC curve was 0.73. Discussion: The postoperative hsPCR isa valuable predictor of the occurrence of POAF in the context of cardiac surgery with extracorporeal circulation.

Valor pronóstico de las fracciones lipídicas basales, en pacientes operados de revascularización miocárdica con circulación extracorpórea / Prognostic value of basal lipid fractions in patients operated on of myocardial revascularization with extracorporeal circulation

Se realizó un estudio observacional, longitudinal y prospectivo en 60 pacientes, durante el período de enero 2008-2009, con el objetivo de determinar el valor pronóstico de estas fracciones lipídicas basales y su relación con la ocurrencia de eventos clínicos adversos, en el posoperatorio de pacientes con indicación de revascularización miocárdica con circulación extracorpórea. Como resultados obtuvimos, que las concentraciones basales del colesterol total, los triglicéridos, y el colesterol asociado a las lipoproteínas de alta densidad, a las lipoproteínas de baja densidad y a las lipoproteínas de muy baja densidad, se modificaron durante el proceder quirúrgico y en la sala de recuperación. Además, se demostró una disminución significativa de las lipoproteínas de alta densidad y una tendencia de aumentar el nivel de colesterol, en el grupo de pacientes que manifestó eventos clínicos adversos, y se observó también, una estrecha asociación entre estos eventos y estas 2 variables lipídicas (p< 0,05). Se concluyó que los pacientes que tienen de base un perfil lipídico alterado son más susceptibles a desarrollar eventos clínicos adversos, en el posoperatorio inmediato de la cirugía coronaria con circulación extracorpórea(AU)

A prospective, longitudinal and observational study was conducted in 60 patients from January 2000-2009 to determine the prognostic value of these basal lipid fractions and its relation to occurrence of adverse clinical events in postoperative period of patients with an extracorporeal circulation myocardial revascularization indication. As result, the basal concentrations of total cholesterol, triglycerides and the cholesterol associated with high density lipoproteins (HDL) were modified during the surgical procedure and in the recovery unit. Also, it was shown a significant decrease of HDL and a trend to increase the cholesterol level as well as a close association among these events and these lipid variables (p <0,05). We conclude that patients with an altered lipid profile basis are more liable to develop adverse clinical events in the immediate postoperative period of coronary surgery with extracorporeal circulation(AU)

Resultados de la revascularización coronaria en el cardiocentro del Hospital Hermanos Ameijeiras, en un período de 20 años / Results of coronary revascularization in the Cardiac Center of the Hermanos Ameijeiras Clinical Surgical Hospital over 20 years

INTRODUCCIÓN. En el cardiocentro del Hospital Hermanos Ameijeiras, la cirugía cardiovascular se practica hace más de 20 años, a lo largo de los cuales se fueron introduciendo y desarrollando diversas técnicas de revascularización miocárdica. El objetivo de esta investigación fue describir los resultados de la cirugía de revascularización coronaria en ese período. MÉTODOS. Se realizó una investigación descriptiva, longitudinal, retrospectiva, con cortes transversales quinquenales, comparando cada quinquenio con el siguiente. Del total de 763 pacientes sometidos a revascularización coronaria en el período comprendido entre enero de 1985 y diciembre del 2004, se excluyeron 17 por presentar historias clínicas extraviadas o con datos incompletos y 15 pacientes operados sin circulación extracorpórea, por lo que el universo de estudio quedó conformado por 731 pacientes, operados todos con circulación extracorpórea. RESULTADOS. Predominaron los pacientes con edades entre 51 y 60 años de edad y del sexo masculino; con el tabaquismo y la hipertensión arterial como factores de riesgo más frecuentes. Los estados clínicos predominantes fueron la angina estable crónica y la angina inestable. Predominó la revascularización con tres puentes con tendencia al ascenso, así como el uso de la vena safena, pero con una evolución ascendente en el empleo de la arteria mamaria interna y disminución en la implantación de la vena safena como único conducto. El tiempo de circulación extracorpórea y de paro anóxico mostró una tendencia a la disminución. Las complicaciones más frecuentes fueron las sepsis urinaria y respiratoria. Disminuyeron las muertes por causas cardíacas, entre las cuales el fallo multiorgánico y el bajo gasto cardíaco fueron las principales. Disminuyó el bajo gasto transoperatorio pero hubo tendencia al aumento en el posoperatorio y del fallo multiorgánico. CONCLUSIONES. El uso de revascularización coronaria tuvo una tendencia ascendente en estos 20 años, sobre todo en pacientes de la tercera edad y del sexo masculino, en los que el tabaquismo y la hipertensión arterial fueron los factores de riesgo mayormente asociados. Predominó la revascularización con tres puentes y el uso de la safena, pero con tendencia al uso ascendente de la arteria mamaria interna. La mortalidad tuvo un comportamiento decreciente(AU)

INTRODUCTION. In Cardiac Center of the Hermanos Ameijeiras Clinical Surgical Hospital cardiovascular surgery is done from more twenty years ago introducing and developing different techniques of myocardial revascularization. The objective of present research was to describe the results of coronary revascularization over that period. METHODS. A retrospective, longitudinal and descriptive research with five-year cross-sectional cuts was conducted comparing each five-year period with the following one. From the total of 763 patients underwent coronary revascularization from January,1985 to December, 2004, 17 patients were excluded due to missing medical records or with incomplete data and 15 patients operated on without extracorporeal circulation, thus, the universe included 731 patients operated on with this technique. RESULTS. There was predominance the patients aged between 51 and 60years and male sex where smoking and high blood pressure were the more frequent risk factors. The predominant clinical stages were the chronic stable angina and the unstable angina as well as revascularization with three bridges and a trend to rise, as well as the saphenous vein use but with an ascending evolution as the only duct. The time of extracorporeal circulation and anoxic arrest showed a trend to decrease. The more frequent complications were the urinary and respiratory sepsis. There was a decrease of deaths from cardiac causes among which the multiorgan failure and the low cardiac output were the major ones. The low transoperative output decreased but there was a trend to increase during the postoperative one and of the multiorgan failure. CONCLUSIONS. The use of coronary revascularization showed a ascending trend over these 20years mainly in third age patients and of the male sex where the smoking and the high blood pressure were the more associated risk factors. There was predominance of three bridges revascularization and use of saphenous vein but with an increasing use of internal mammary artery. Mortality was a decreasing behavior(AU)

Os leucócitos e a resposta inflamatória na lesão de isquemia-reperfusão / Leukocytes and the inflammatory response in ischemia-reperfusion injury

Os eventos de isquemia-reperfusão desencadeiam uma resposta inflamatória sistêmica que pode levar a lesões celulares e até falência de órgãos. Tais repercussões são notadas no pós-operatório de cirurgias, em especial, com o uso de circulação extracorpórea. Sabe-se, atualmente, que os leucócitos exercem importante papel neste processo. Assim, este estudo aborda o papel dos leucócitos na fisiopatologia das lesões de isquemia-reperfusão e a ativação das cascatas inflamatórias por esse processo e procura auxiliar na compreensão destes mecanismos assim como trazer contribuições acerca das abordagens terapêuticas que possam atenuá-los. Esta revisão bibliográfica retrospectiva foi realizada a partir de documentos científicos publicados nos últimos dez anos, em português e inglês, indexados em bases de dados internacionais Medline e SciELO e de textos clássicos relacionados. Os descritores pesquisados foram: isquemia-reperfusão, leucócitos, resposta inflamatória, circulação extracorpórea, efeitos adversos e apoptose.

The events of ischemia-reperfusion injury triggers a systemic inflammatory response and can lead to cellular injury and organ failure. Such effects are noted in the postoperative recovery, especially with the use of cardiopulmonary bypass. Nowadays, it is known that leukocytes play an important role in this process. Therefore, this study addresses the role of leukocytes in the physiopathology of ischemia-reperfusion injuries and activation of inflammatory cascades through this process and seek to help in the understanding of these mechanisms as well as to bring contributions on the therapeutic approaches that can mitigate them. This retrospective review was performed from indexed scientific papers published over the last ten years in Portuguese and English in international databases MEDLINE and SciELO and related classic texts. The descriptors investigated were: ischemia-reperfusion, leukocytes, inflammatory response, cardiopulmonary bypass, adverse effects and apoptosis.

Incidência de complicações pulmonares na cirurgia de revascularização do miocárdio / Incidence of pulmonary complications in myocardial revascularization / Incidencia de complicaciones pulmonares en la cirugía de revascularización del miocardio

FUNDAMENTO: No período do peri-operatório, os cuidados têm sido cada vez mais criteriosos, entretanto, as complicações pulmonares após a abordagem cirúrgica ainda são frequentes, predispondo o paciente a um maior tempo de internação ou ao óbito. OBJETIVO: Descrever a incidência de complicações pulmonares e identificar a sua associação com tempos de circulação extracorpórea (CEC); cirurgia e isquemia; número de enxertos; localização e tempo de drenos após cirurgia de revascularização do miocárdio (CRM). MÉTODOS: Nesta coorte contemporânea, foram estudados 202 pacientes em hospital universitário de referência para cardiologia no sul do Brasil, submetidos à CRM eletiva com ponte safena e artéria mamária interna com CEC, no período de abril/2006 a novembro/2007. Os desfechos considerados foram: tempo de ventilação mecânica; surgimento de pneumonia; atelectasia; derrame pleural; hora da retirada e localização dos drenos; e tempo de internação. RESULTADOS: Observou-se algum tipo de complicação pulmonar em 90 dos 202 pacientes. A frequência de derrame pleural foi de 84 por cento e a de atelectasia foi de 65 por cento. Apresentaram associação com complicações pulmonares os tempos de CEC (p = 0,003), cirúrgico (p = 0,040) e isquemia (p = 0,001); o tempo de permanência de drenos (p = 0,050) e a localização pleural dos drenos (p = 0,033), além de idade (p = 0,001), fração de ejeção (p = 0,010), diagnóstico de asma (p = 0,047) e exame radiológico de tórax pré-operatório anormal (p = 0,029). CONCLUSÃO: Variáveis relacionadas à complexidade do ato cirúrgico e comorbidades pré-existentes estão associadas a uma alta incidência de complicações pulmonares no pós-operatório. Esses dados reforçam a importância da avaliação clínica peri-operatória para detecção precoce de complicação respiratória após CRM.

BACKGROUND: Despite the increasingly careful attempts to reduce perioperative risks, pulmonary complications following surgery are still very common, leading to longer length of hospital stays or death. OBJECTIVE: To describe the incidence of pulmonary complications and identify their association with duration of extracorporeal circulation (ECC), surgery and ischemia, number of bypass grafts performed, location of drains and length of drainage following myocardial revascularization (MRV). METHODS: This contemporaneous cohort consisted of 202 patients undergoing elective myocardial revascularization (MRV) with saphenous vein graft and internal mammary artery graft and ECC, at a referral university cardiology hospital in Southern Brazil, from April 2006 to November 2007. The following outcomes were analyzed: duration of mechanical ventilation; pneumonia onset; atelectasis; pleural effusion; location of drains and time of removal; and length of hospital stay. RESULTS: Of the 202 patients, 90 developed some sort of pulmonary complication. The incidence of pleural effusion was 84 percent, whereas atelectasis was 65 percent. The following variables were associated with pulmonary complications: duration of ECC (p = 0.003), surgery (p = 0.040) and ischemia (p = 0.001); length of drainage (p = 0.050) and location of pleural drains (p = 0.033); age (p = 0.001); ejection fraction (p = 0.010); diagnosis of asthma (p = 0.047) and preoperative abnormal chest X-ray findings (p = 0.029). CONCLUSION: Variables related to the complexity of the surgery and preexisting comorbidities are associated with a high incidence of postoperative pulmonary complications. These data reinforce the importance of having patients undergo perioperative clinical assessment to detect early respiratory complications after MRV.

FUNDAMENTO: En el período del peri-operatorio, los cuidados han sido cada vez más criteriosos, entre tanto, las complicaciones pulmonares después del abordaje quirúrgico aun son frecuentes, predisponiendo al paciente a un mayor tiempo de internación o al óbito. OBJETIVO: Describir la incidencia de complicaciones pulmonares y identificar su asociación con tiempos de circulación extracorporal (CEC); cirugía e isquemia; número de injertos; localización y tiempo de drenajes después de cirugía de revascularización del miocardio (CRM). MÉTODOS: En esta cohorte contemporánea, fueron estudiados 202 pacientes en hospital universitario de referencia para cardiología en el sur del Brasil, sometidos a la CRM electiva con puente safena y arteria mamaria interna con CEC, en el período de abril/2006 a noviembre/2007. Los desenlaces considerados fueron: tiempo de ventilación mecánica; surgimiento de neumonía; atelectasia; derrame pleural; hora de la retirada y localización de los drenajes; y tiempo de internación. RESULTADOS: Se observó algún tipo de complicación pulmonar en 90 de los 202 pacientes. La frecuencia de derrame pleural fue de 84 por ciento y la de atelectasia fue de 65 por ciento. Presentaron asociación con complicaciones pulmonares los tiempos de CEC (p = 0,003), quirúrgico (p = 0,040)e isquemia (p = 0,001); el tiempo de permanencia de drenajes (p = 0,050) y la localización pleural de los drenajes (p = 0,033), además de edad (p = 0,001), fracción de eyección (p = 0,010), diagnóstico de asma (p = 0,047) y examen radiológico de tórax pre-operatorio anormal (p = 0,029). CONCLUSIÓN: Variables relacionadas a la complejidad del acto quirúrgico y comorbilidades pre-existentes están asociadas a una alta incidencia de complicaciones pulmonares en el post-operatorio. Esos datos refuerzan la importancia de la evaluación clínica peri-operatoria para detección precoz de complicación respiratoria después de CRM.

Resultados da implementação de modelo organizacional de um serviço de cirurgia cardiovascular / Results of the establishment of an organizational model in a cardiovascular surgery service

OBJETIVO: A crescente complexidade de pacientes encaminhados a cirurgia cardíaca exige maior eficiência dos serviços que prestam assistência, no sentido de manter a mesma qualidade. O objetivo é examinar o impacto, em curto prazo, da adoção de um modelo organizacional nos resultados cirúrgicos. MÉTODOS: No período entre janeiro de 2006 a junho de 2007, 367 pacientes adultos consecutivos foram submetidos à cirurgia cardiovascular. Os dados pré, intra e pós-operatórios foram colhidos prospectivamente e armazenados em um banco de dados institucional. Modelo organizacional foi implementado em agosto de 2006 e se baseou em trabalho multiprofissional integrado centralizado no paciente, medicina baseada em evidências com condutas padronizadas e resolução de conflitos interpessoais. Os desfechos estudados foram mortalidade hospitalar e eventos combinados (óbito, acidente vascular cerebral, infarto agudo do miocárdio e insuficiência renal aguda), por meio de regressão logística multivariada. RESULTADOS: Após a adoção do modelo, houve redução da mortalidade hospitalar (de 12 por cento para 3,6 por cento, risco relativo= 0,3; P=0,003) e de eventos combinados (de 22 por cento para 15 por cento, risco relativo= 0,68; P=0,11). Operações realizadas anteriormente à implementação do modelo estiveram associadas independentemente com maior mortalidade (OR=2,5; P=0,04), ajustada para características préoperatórias e complexidade pelo EuroSCORE. Outros preditores de mortalidade foram idade > 65 anos (OR=6,36; IC95 por cento 2,57 - 17,21; P<0,0001) e o tempo de circulação extracorpórea > 145 minutos (OR=8,57; IC95 por cento 3,55 - 21,99; P<0,0001). CONCLUSÃO: A rápida melhora dos resultados cirúrgicos depende da composição de serviços de cirurgia cardíaca embasados em modelos organizacionais semelhantes ao proposto.

OBJECTIVE: Increasing complexity of patients referred to cardiac surgery demands more effective heart centers, in order to maintain the same quality. The aim of this study is to examine the short-term effect of adoption of an organizational model on surgical outcomes. METHODS: From January 2006 to June 2007, 367 consecutive adult patients underwent cardiovascular surgery. Pre-, intra- and postoperative data were prospectively collected and transferred to an institutional database. Organizational model was established in August 2006, and based on integrated multiprofessional team work patient-centered, evidence-based medicine with standardized patient care and personal conflict management. The outcomes studied were hospital mortality and combined adverse events (death, stroke, acute myocardial infarction and acute renal failure), by using multivariate logistic regression analysis. RESULTS: After establishment of such model, there was reduction of hospital mortality (from 12 percent to 3.6 percent, relative risk= 0.3; P=0.003) and combined events (from 22 percent to 15 percent, relative risk=0.68; P=0.11). Operations performed previously to the model were independently associated with higher mortality (OR=2.5; P=0.04), adjusted to preoperative characteristics and Euroscore risk stratification system. Other predictors of mortality were age > 65 years (OR=6.36; 95 percentCI 2.57 - 17.21; P<0.0001) and cardiopulmonary bypass time > 145 minutes (OR=8.57; 95 percentCI 3.55 - 21.99; P<0.0001). CONCLUSION: Marked improvements in surgical outcomes depend on development of cardiac surgery centers based on organizational models similar to the model proposed in this study.

Avaliação do óxido nítrico exalado em pacientes submetidos à revascularização do miocárdio com circulação extracorpórea / Evaluation of exhaled nitric oxide in patients undergoing myocardial revascularization with cardiopulmonary bypass / Evaluación del óxido nítrico exhalado en pacientes sometidos a la revascularización del miocardio con circulación extracorpórea

JUSTIFICATIVA E OBJETIVOS: A circulação extracorpórea (CEC) pode causar disfunção pulmonar. As alterações inflamatórias podem afetar a liberação de óxido nítrico (NO). Objetivou-se avaliar o NO exalado em pacientes submetidos à revascularização do miocárdio (RM) com CEC. MÉTODO:Foram estudados prospectivamente nove pacientes adultos submetidos à RM com CEC. Inicialmente, foi coletada amostra de ar para análise de NO no sistema que alimenta o aparelho de anestesia. A seguir, anestesia iniciada por via venosa com etomidato (0,3 mg.kg-1), sufentanil (0,3 µg.kg-1), pancurônio (0,08 mg.kg-1) e mantida com isoflurano (0,5 a 1,0 CAM) e sufentanil (0,5 µg.kg-1.h-1). O volume corrente fixado a 8 mL.kg-1, com FIO2 de 0,6, exceto durante a CEC. Trinta minutos depois da indução, e trinta após a CEC, três amostras sequenciais de ar exalado foram colhidas para análise de NO, por quimioluminescência. Os dados foram analisados por meio do teste t de Student. RESULTADOS: O valor do NO do ar ambiente foi de 5,05 ± 3,37 ppb. O NO exalado decresceu após a CEC, variando de 11,25 ± 5,65 ppb para 8,37 ± 3,17 ppb (p = 0,031). CONCLUSÕES: A redução do NO exalado pós-CEC observada nesse estudo não permite confirmar o papel dessa molécula como marcador de lesão pulmonar. Entretanto, os variados graus de colapso do parênquima pulmonar, o método de obtenção dos dados, os fármacos utilizados, dentre outros, podem ter contribuído para a redução.

BACKGROUND AND OBJECTIVES: Cardiopulmonary bypass (CPB) can cause pulmonary dysfunction. Inflammatory changes may affect the release of nitric oxide (NO). The objective of this study was to evaluate exhaled NO in patients undergoing myocardial revascularization (MR) with CPB. METHODS: This is a prospective study with nine adult patients undergoing MR with CPB. Initially, air samples were collected to analyze the presence of NO in the system that feeds the anesthesia equipment. Intravenous anesthesia was then initiated with ethomidate (0.3 mg.kg-1), sufentanil (0.3 µg.kg-1), and pancuronium (0.08 mg.kg-1), and maintained with isoflurane (MAC from 0.5 to 1.0) and sufentanil (5 µg.kg-1.h-1). Tidal volume was fixed at 8 mL.kg-1 and FiO2 0.6, except during CPB. Thirty minutes after induction and 30 minutes after CPB, three sequential samples of exhaled air were collected for NO analysis by chemiluminescence. Data were analyzed by the Student t test. RESULTS: The level of NO in room air was 5.05 ± 3.37 ppb. Levels of exhaled NO decreased after CPB, varying from 11.25 ± 5.65 ppb to 8.37 ± 3.71 ppb (p = 0.031). CONCLUSIONS: The reduction of exhaled NO after CPB observed in this study does not confirm the role of this molecule as a marker of pulmonary lesion. However, the different degrees of pulmonary parenchymal collapse, the method used to collect the data, and the drugs, among others, could have contributed for this reduction.

JUSTIFICATIVA Y OBJETIVOS: La circulación extracorpórea (CEC), puede causar una disfunción pulmonar. Las alteraciones inflamatorias pueden afectar la liberación de óxido nítrico (NO). Se buscó evaluar el NO exhalado en pacientes sometidos a la revascularización del miocardio (RM) con CEC. MÉTODO: Se estudiaron prospectivamente nueve pacientes adultos sometidos a la RM con CEC. Inicialmente fue recolectada una muestra de aire para el análisis de NO en el sistema que alimenta el aparato de anestesia. A continuación, se inició la anestesia por vía venosa con etomidato (0,3 mg.kg-1), sufentanil (0,3 µg.kg-1), pancuronio (0,08 mg.kg-1) y se mantiene con isoflurano (0,5 a 1,0 CAM) y sufentanil (0,5 µg.kg-1.h-1). El volumen corriente fijado fue 8 mL.kg-1, con FiO2 de 0,6 excepto durante la CEC. Treinta minutos después de la inducción y treinta minutos después de la CEC, tres muestras secuenciales de aire exhalado fueron recogidas para análisis de NO, por quimioluminescencia. Los datos fueron analizados por medio del test t Student. RESULTADOS: El valor del NO del aire ambiente fue de 5,05 ± 3,37 ppmm. El NO exhalado se redujo después de la CEC, variando de 11,25 ± 5,65 ppmm para 8,37 ± 3,17 ppmm (p = 0,031). CONCLUSIONES: La reducción del NO exhalado pos-CEC, observada en este estudio, no permite confirmar el papel de esta molécula como marcador de lesión pulmonar. Sin embargo, los variados grados de colapso del parénquima pulmonar, el método de obtención de los datos, y los fármacos utilizados, entre otros, pueden haber contribuido para esa reducción.

Degree of risk related to procedures performed in conjunction with surgical myocardial revascularization in octogenarians

INTRODUCTION/OBJECTIVES: We determined the degree of risk produced by the association of other surgical procedures with surgical myocardial revascularization in octogenarian patients and identified the risk factors that best explain hospital mortality. METHODS: This study was an observational analytical historical cohort study involving octogenarians operated on at our institution between January 1, 2000 and January 1, 2005. We stratified the objective population as follows: Group 1 comprised octogenarians revascularized without associated procedures, and Group 2 comprised octogenarians revascularized with associated procedures. Statistical analyses included the t test for independent samples and multiple logistic regression analysis. Significance was accepted with an alpha error of 5 percent. RESULTS: Univariate analyses revealed the following clinical and statistically significant variables: hospital mortality (P=0.002), diabetes mellitus (P=0.017), preoperative endocarditis (P=0.001), cardiogenic shock (P=0.019), use of an intra-aortic balloon pump (P=0.026), preoperative risk score (Parsonnet), P<0.001, procedure associated with revascularization (P<0.001), medium number of affected coronary arteries (P<0.001), use of extracorporeal circulation (P<0.001), time of extracorporeal circulation (P<0.001), number of distal anastomoses (P=0.002), graft type (P<0.001), postoperative breathing support (P<0.001), stroke (P<0.001), infection (P=0.002), creatinine level (P=0.018), and quality of life score (P=0.050). DISCUSSION/CONCLUSIONS: In octogenarian patients, the need for a procedure associated with surgical myocardial revascularization produces an absolute increase in hospital mortality risk of 45 percent. The variables that contributed to hospital mortality were preoperative endocarditis, preoperative cardiogenic shock, the use of extracorporeal circulation, the length of time of extracorporeal circulation, postoperative creatinine level, ...

Circulação extracorpórea em adultos no século XXI: ciência, arte ou empirismo?: [revisão] / Adult cardiopulmonary bypass in the twentieth century: science, art or empiricism?: [review]

A presente revisão tem por objetivo ressaltar alguns aspectos pouco discutidos da circulação extracorpórea (CEC), levando-se em consideração fisiologia, fisiopatologia e algumas novas tecnologias de perfusão. Assim, alguns aspectos, até certo ponto filosóficos, motivaram a elaboração dessa revisão: a) Preservar e atualizar os conhecimentos do cirurgião sobre a CEC, pelo simples fato de manter a sua liderança pedagógica sobre a sua equipe; b) Questionar se pacientes idosos e diabéticos pelas suas características individuais, assim como adotado para crianças, talvez merecessem protocolos mais apropriados; c) Questionar a reação inflamatória sistêmica causada pela exposição do sangue à superfície não endotelizada do circuito de CEC diante da importância crescente do contato do sangue com a ferida cirúrgica; d) Em relação ao tratamento da síndrome vasoplégica, o azul de metileno continua sendo a melhor opção terapêutica, embora, muitas vezes não seja eficiente pela existência de uma "janela terapêutica" embasada na dinâmica da ação da guanilato ciclase (saturação e síntese "de novo") e; finalmente, e) Razão da escolha do título, ressaltando que, em seus moldes atuais, a CEC seria conseqüência do empirismo, arte, ou da ciência? A mensagem final vem com a convicção de que tanto o empirismo, a arte e a ciência são muito fortes em se tratando da CEC.

The aim of the present review is to highlight some less discussed aspects of the cardiopulmonary bypass (CPB), taking into consideration the physiology, physiopathology, and some new technologies of perfusion. Thus, some points, to a certain extent philosophical, have motivated this revision: a) To preserve and update the surgeon knowledge regarding CPB, even to keep his/her pedagogical leadership on his/her surgical team; b) To question if elderly and diabetic patients, as a result of their individual characteristics deserve more appropriate protocols similar to those adopted for children; c) One third aspect would be the questioning of the systemic inflammatory reaction caused by the blood exposure to CPB non-endothelized circuit surface, in face of the increasing importance of blood contact with the surgical wound; d) In relation to the treatment of the vasoplegic syndrome, methylene blue continues being the best therapeutical option, even so, many times are not efficient on account of a highly probable existence of a "therapeutical window" based on the guanylate cyclase dynamics of action (saturation and synthesis "de novo") and; finally, e) The reason of the title, highlighting that based on its current patterns, would the CPB be an outcome of empiricism, art, or science? The bottom line of this article carries the certainty of that as much as the empiricism, art, and science are highly related to CPB.

Práctica transfusional en pacientes adultos sometidos a cirugía cardíaca con circulación extracorpórea: experiencia de la Pontificia Universidad Católica de Chile / Prediction of blood transfusion need in patients undergoing open heart surgery: the experience of Catholic University Hospital, Chile

Antecedentes: La cirugía cardíaca se asocia a un alto consumo de sangre homóloga. Si conocemos los factores quepredicen una mayor necesidad de transfusión, podremos implementar mejores estrategias de ahorro sanguíneo. Objetivo: Describir la práctica transfusional en pacientes adultos sometidos a cirugía con circulación extracorpórea (CEC) en la Pontificia Universidad Católica de Chile. Materiales y métodos: Se recolectaron en forma retrospectiva los datos de 194 pacientes adultos sometidos a cirugía cardíaca con CEC, entre octubre de 2003 y marzo de 2004. Se realizó una descripción de la práctica transfusional y un análisis de riesgo uni y multivariado. Resultados: El 61,8 por ciento de los pacientes se transfundieron durante la hospitalización. La transfusión intraoperatoria se relacionó con sangrado y la transfusión postoperatoria con la corrección de un hematocrito bajo. Los factores predictores de transfusión fueron cirugía de urgencia, tiempo prolongado de CEC, edad avanzada y un menor hematocrito al momento de ingresar a la unidad de cuidado postoperatorio. El hematocrito bajo al inicio de la cirugía, una menor temperatura durante CEC y un mayor sangrado en el postoperatorio predijeron el uso de más de dos unidades de glóbulos rojos (GR).Los pacientes que recibieron más de 2 unidades de GR presentaron en forma significativa mayor incidencia de neumonía, insuficiencia respiratoria y sepsis. Conclusiones: La transfusión sanguínea en cirugía cardíaca se relaciona directamente con la complejidad de los pacientes y los procedimientos. Las técnicas de ahorro de sangre deben dirigirse hacia la disminución del sangrado, la hemodilución y a estrictos criterios de transfusión intra y postoperatorios.

Background: Cardiac surgery is associated with frequent use of homologous blood. The knowledge of factors that influence the need for transfusion might help us implement strategies to avoid unnecessary blood administration. Objective: To describe the current transfusion practices in adults undergoing open cardiac surgery with extra corporeal circulation (ECC) at the Pontificia Universidad Católica of Chile Hospital. To identify factors that predict the use of transfusion. Methods: Data from 194 adult patients submitted to cardiac surgery with ECC between October 2003 and March 2004 were obtained retrospectively. Transfusional practices were identified. Uni and multivariate risk analysis was used to predict the need for transfusion.Results: 61,8 percent of patients were transfused during their hospital stay. Intraoperative transfusion was related to bleeding while post operative transfusion was performed to correct a low hematocrit value. Factors predicting transfusion were: emergency surgery, prolonged EEC time, older age and lower hematocrit value when entering the ICU. Preoperative hematocrit, lower temperature during ECC and post operative bleeding predicted the use of more than 2 red blood cell (RBC) packs. Patients receiving more than 2 RBC packs had a significantly higher incidence of pneumonia, sepsis and respiratory failure. Conclusion: Blood transfusion during cardiac surgery is directly related to complexity of procedures and severeness of patient illness. Blood saving techniques must be directed to reducing the amount of bleeding, allowing hemodilution and defining strict criteria for intra and post operative transfusions.