Clinical Pearls of Venoarterial Extracorporeal Membrane Oxygenation for Cardiogenic Shock

Extracorporeal membrane oxygenation (ECMO) is a technique that uses a pump to drain blood from a body, circulate blood through a membrane lung, and return the oxygenated blood back into the body. Venoarterial (VA) ECMO is a simplified version of the heart-lung machine that assists native pulmonary and/or cardiac function. VA ECMO is composed of a drainage cannula in the venous system and a return cannula in the arterial system. Because VA ECMO can increase tissue perfusion by increasing the arterial blood flow, it is used to treat medically refractory cardiogenic shock or cardiac arrest. VA ECMO has a distinct physiology that is referred to as differential flows. It can cause several complications such as left ventricular distension with pulmonary edema, distal limb ischemia, bleeding, and thromboembolism. Physicians who are using this technology should be knowledgeable on the prevention and management of these complications. We review the basic physiology of VA ECMO, the mechanism of complications, and the simple management of VA ECMO.

Cardiopulmonary bypass: development of John Gibbon's heart-lung machine / Circulação extracorpórea: desenvolvimento da máquina de coração-pulmão de John Gibbon

Abstract Objective: To provide a brief review of the development of cardiopulmonary bypass. Methods: A review of the literature on the development of extracorporeal circulation techniques, their essential role in cardiovascular surgery, and the complications associated with their use, including hemolysis and inflammation. Results: The advancement of extracorporeal circulation techniques has played an essential role in minimizing the complications of cardiopulmonary bypass, which can range from various degrees of tissue injury to multiple organ dysfunction syndrome. Investigators have long researched the ways in which cardiopulmonary bypass may insult the human body. Potential solutions arose and laid the groundwork for development of safer postoperative care strategies. Conclusion: Steady progress has been made in cardiopulmonary bypass in the decades since it was first conceived of by Gibbon. Despite the constant evolution of cardiopulmonary bypass techniques and attempts to minimize their complications, it is still essential that clinicians respect the particularities of each patient's physiological function. .

Resumo Objetivo: Relatar de forma simples e resumida o desenvolvimento da circulação extracorpórea. Métodos: Realizada revisão de literatura sobre a evolução da circulação extracorpórea, seu papel fundamental para cirurgia cardiovascular e as complicações que podem surgir após o seu uso, dentre elas, a hemólise e a inflamação. Resultados: O processo de desenvolvimento da circulação extracorpórea foi fundamental, diminuindo as complicações desencadeadas por ela, que acabam por repercutir no paciente, variando de lesões de graus variados até falência de múltiplos órgãos. Os pesquisadores estudaram quais as agressões que a circulação extracorpórea poderia suscitar no organismo humano. Possíveis soluções surgiram e, consequentemente, meios mais adequados para uma condução mais segura do pós-operatório foram propostas. Conclusão: A circulação extracorpórea progrediu a passos firmes e seguros ao longo destas últimas décadas desde a sua concepção por Gibbon. Apesar da sua evolução e das condutas realizadas na tentativa de amenizar as complicações, o respeito aos detalhes das funções fisiológicas do paciente é fundamental. .

Extracorporeal Membrane Oxygenation: Past, Present and Future / 대한내과학회지

Extracorporeal membrane oxygenation (ECMO) was originated from heart-lung machine for cardiac surgery. This technique that receive the blood from venous system, oxygenate it and support to selected patients with severe respiratory or cardiac failure as flow and oxygen. ECMO can provide partial or total support, is temporary, and requires systemic anticoagulation. ECMO controls gas exchange and perfusion, stabilizes the patient physiologically, decreases the risk of ongoing iatrogenic injury, and allows enough time for decision, diagnosis, treatment, and recovery from the primary injury or disease. The two major ECMO modalities are venoarterial and venovenous. Until 1980s, ECMO usually used to pediatric respiratory failure. However after H1N1 influenza epidemic in the world, venovenous ECMO support for adult has been increased rapidly. Venoarterial ECMO support for cardiac failure and resuscitation also abruptly has been increased. As a support modality, cannula position and possibility of complication is different. Survival rate of ECMO has a range from 30% in extracorporeal cardiopulmonary resuscitation to 70% for acute myocarditis and acute respiratory distress syndrome in adult, and better in neonate and pediatrics. Advancing ECMO technology and increasing experience with ECMO techniques have improved patient outcomes, reduced complications and expanded the potential applications of ECMO. Awareness of the indications and implications of ECMO among physicians managing patients with severe but potentially reversible respiratory or cardiac failure may help facilitate better communication between health care teams and improve patient recovery.

Educación medica continua: displasia broncopulmonar: enfermedad pulmonar crónica del recien nacido / Continuing medical education: bronchopulmonary dysplasia: chronic lung disease of the newborn

La displasia brocopulmonar (DBP) corresponde a un daño pulmonar crónico secundario al manejo ventilatorio del prematuro (oxigenoterapía, volutrauma o barotrauma) , así como las infecciones respiratorias que inducen a mecanismos de inflamación pulmonar con destrucción y fibrosis.

Assessment of liver function test change after open heart surgery

Open heart surgery requires using cardiopulmonar bypass [CPB]. CPB stimulates complement, coagulation and immune systems and non-pulsatile flow has an important effect on body organs, like liver. Activation of this system produces severe inflammatory reaction with subsequent organ damage. This study was designated to examine the influence of CPB on simple liver function test. A total of 100 patients with coronary artery disease [CAD] and valvular heart disease were scheduled for surgery and entered in a clinical study to assess the effects of intra-operative variables on simple liver function tests [SGOT, SGPT, alkaline phosphatase, and bilirubin] measured after three consecutive days with an auto-analyzer device. Patients with a past medical history of right heart failure, jaundice or hepatitis were excluded from our study. Independent and continuous variables, such as age, gender, pump time, temperature in pump, transfusion, were measured and recorded, and effect of these variables on mean values of liver function test after operation was evaluated by generalized linear method [GLM] and two way methods. This test entered to model as dependent variables and other variables as fixed or co-variables. The mean values of liver function test before and after operation were compared by ANOVA and Turkey's post hoc test and p-value <0.05 was considered significant. The pump hypotension [BP<50mmHg] had an effect on SGPT 1 and SGOT 2 and SGOT 3 [P<0.004]. Change of SGOT 2 test was significant in the pump time longer than 100 minutes. SGOT 1, SGOT 3, SGPT 1, alkaline phosphatase 1 changes related to CPB temperature was seen in temperature less than 28, rise of alkaline phosphatase 1,2, 3 was significant [P<0.01] with long anesthesia time. Type of operation had a significant effect on direct bilirubin 2, 3 and type of pump had an effect on SGOT 2 and direct bilirubin 1. Sex had effect on SGOT 2 but age did not have any effect on liver function test. Transfusion volume raised SGOT 1 and alkaline phosphatase 1 and direct bilirubin 2 and long pump time raised SGOT 2. Age had no influence on liver function test. The most sensitive tests to find hepatic injury with hypothermia were SGPT 1 and alkaline phosphstase 1 and SGOT 1. In CPB hypotension, SGPT 1, 2 tests were significant and in long pump time, SGOT 2 was sensitive for knowing hepatic cell damage

The significance of erythrocyte fragment count to predicting hemolysis in roller pumps / 生物医学工程学杂志

Hemolysis in blood pumps has been measured by various in vitro tests, in which normalized index of hemolysis (NIH) was established. As NIH is complicated and difficult to calculate, erythrocyte fragment count (EFC) is proposed in the present study to predict hemolysis in roller pumps. Five paired in vitro tests were conducted using the POLYSTAN pediatric pump (group A) and COBE pump (group B). Ten whole blood samples (400ml) were circled in the roller pump for 16 hours. Erythrocyte fragments count and plasma-free hemoglobin (FHb) were measured before pumping and every 2 hours through circulation after 4 hours pumping. The morphological changes of erythrocyte were observed by scanning electron microscope. Simple linear regression analysis showed the two groups' EFC and FHb levels increased linearly during a long period of pumping, and the coefficient of determination (R2) was 0.64. These data suggested that Erythrocyte fragments count could be used as an index in evaluating the in vitro hemolytic properties of blood pumps.

Avaliação dos efeitos da circulação extracorpórea na formação de cálculos biliares / Evaluation of extracorporeal circulation effects on gallstone formation

OBJETIVO: Verificar a associação entre o uso da circulação extracorpórea e o desenvolvimento de colelitíase. MÉTODO: Foram estudados 135 pacientes coronariopatas acompanhados na Disciplina de Cardiologia da Universidade Federal de São Paulo - Escola Paulista de Medicina, no período de janeiro de 2000 a setembro de 2002, distribuídos em três grupos: Grupo 1 - 51 pacientes tratados clinicamente; Grupo 2 - 43 pacientes revascularizados sem circulação extracorpórea e Grupo 3 - 41 pacientes revascularizados com circulação extracorpórea. Foram controladas as variáveis sexo, idade, índice de massa corpórea e doenças associadas entre os grupos e foi realizada ultra-sonografia total de abdome em todos os pacientes, aos doze meses de tratamento (clínico ou cirúrgico), para verificar a existência de colelitíase. RESULTADOS: A prevalência de colelitíase encontrada nos grupos foi: Grupo 1 - 7,84 por cento; Grupo 2 - 11,62 por cento e Grupo 3 - 19,51 por cento. Não houve diferença estatisticamente significante entre os grupos quanto à existência de colelitíase (p=0,248). CONCLUSAO: Baseado neste estudo não se pode afirmar que o uso da circulação extracorpórea predisponha a maior prevalência de colelitíase.

The Comparative Study of on Pump CABG during Pulsatile (T-PLS(TM)) and Nonpulsatile (Bio-pump(TM)) Perfusion / 대한흉부외과학회지

BACKGROUND: Pulsatile pumps for extracorporeal circulation have been known to be better for tissue perfusion than non-pulsatile pumps but be detrimental to blood corpuscles. This study is intended to examine the risks and benefits of T-PLS(TM) through the comparison of clinical effects of T-PLS(TM) (pulsatile pump) and Bio-pump(TM) (non-pulsatile pump) used for coronary bypass surgery. MATERIAL AND METHOD: The comparison was made on 40 patients who had coronary bypass using T-PLS(TM) and Bio-pump(TM) (20 patients for each) from April 2003 to June 2005. All of the surgeries were operated on pump beating coronary artery bypass graft using cardiopulmonary extra-corporeal circulation. Risk factors before surgery and the condition during surgery and the results were compared. RESULT: There was no significant difference in age, gender ratio, and risk factors before surgery such as history of diabetes, hypertension, smoking, obstructive pulmonary disease, coronary infarction, and renal failure between the two groups. Surgery duration, hours of heart-lung machine operation, used shunt and grafted coronary branch were little different between the two groups. The two groups had a similar level of systolic arterial pressure, diastolic arterial pressure and mean arterial pressure, but pulse pressure was measured higher in the group with T-PLS(TM) (46+/-15 mmHg in T-PLS(TM) vs 35+/-13 mmHg in Bio-pump(TM), p<0.05). The T-PLS(TM)-operated patients tended to produce more urine volume during surgery, but the difference was not statistically significant (9.7+/-3.9 cc/min in T-PLS(TM) vs 8.9+/-3.6 cc/min in Bio-pump(TM), p=0.20). There was no significant difference in mean duration of respirator usage and 24-hour blood loss after surgery between the two groups. Plasma free Hb was measured lower in the group with T-PLS(TM) (24.5+/-21.7 mg/dL in T-PLS(TM) versus 46.8+/-23.0 mg/dL in Bio-pump(TM), p<0.05). There was no significant difference in coronary infarction, arrhythmia, renal failure and morbidity rate of cerebrovascular disease. There was a case of death after surgery (death rate of 5%) in the group tested with T-PLS(TM), but the death rate was not statistically significant. CONCLUSION: Coronary bypass was operated with T-PLS(TM) (Pulsatile flow pump) using a heart-lung machine. There was no unexpected event caused by mechanical error during surgery, and the clinical process of the surgery was the same as the surgery for which Bio-pump(TM) was used. In addition, T-PLS(TM) used surgery was found to be less detrimental to blood corpuscles than the pulsatile flow has been known to be. Authors of this study could confirm the safety of T-PLS(TM).

Cincuenta años de circulación extracorpórea: la historia de la máquina corazón-pulmón / Fifty years of extracorporeal circulation: the history of the heart-lung machine

Si bien 1953 fue el año del descubrimiento del ADN y de la conquista del Monte Everest, también lo fue de un gran invento tecnológico: la máquina corazón-pulmón, la que ofreció un tratamiento, y en muchos casos cura, a la mayoría de las enfermedades cardiovasculares. En efecto, el 6 de mayo de 1953 John Gibbon logró coronar con el éxito el trabajo de toda su vida al cerrar por primera vez una comunicación interauricular en una joven mujer utilizando una máquina corazón-pulmón de su invención. Sin embargo, previamente la cirugía exploró otros caminos para operar el corazón, como la hipotermia, la que consistía en bajar la temperatura del paciente introduciéndolo en una tina de agua fría para luego efectuar la corrección quirúrgica de una malformación del corazón, en el menor tiempo posible. Por otra parte, luego de su primer éxito, los 4 pacientes siguientes de Gibbon fallecieron, por lo que este abandonó todo intento ulterior, lo que fue seguido por un pesimismo generalizado sobre la circulación extracorpórea. Este fue revertido un año más tarde por Walton Lillehei con la introducción de la "circulación cruzada controlada" en la que un paciente, habitualmente un niño, era conectado a un "donante", habitualmente el padre o la madre, cuyo corazón y pulmón servían como un oxigenador para así efectuar la cirugía a corazón abierto del paciente. Finalmente, es el mismo Lillehei, quien un año más tarde introduce el oxigenador de burbujas, simple y de bajo costo, que abrió las puertas de la cirugía a corazón abierto a todos los cirujanos del mundo. Por esto, para muchos, Walton Lillehei es considerado el "Padre de la Cirugía a Corazón Abierto". Lillehei visitó Chile en 1963 y luego de operar en los pabellones del Hospital Clínico de la Universidad Católica fue nombrado Miembro Honorario de la Facultad de Medicina de dicha Universidad. Previamente, en 1957, Helmuth Jaeger había efectuado el primer cierre quirúrgico exitoso de una comunicación interauricular con circul...

Cincuentenario de la máquina corazón-pulmón Un relato acerca de los pioneros y héroes y de las circunstancias que llevaron al gran invento que permitió el tratamiento y la cura de las enfermedades del corazón / Fifty years of the heart-lung machine. The report about the pioneers and heroes and about the circumstances that elevated the great invention, which allowed the treatment, and in many cases, the cure of heart illnesses

In 1953 DNA was discovered and the Everest was conquered but also a great invention was developed: the heart-lung machine, which allowed the treatment, and in many cases, the cure of most cardiovascular illnesses. In fact, on May 6, 1953 John Gibbon crowned with success the work of his entire life closing for the first time an atrial septal defect in a young woman using a heart-lung machine of his own invention. Before that, surgeons had explored other roads like hypothermia, cooling the patient in a cold water tub and then rapidly performing the surgical correction of a heart malformation. After his first success, the following 4 patients of Gibbon died, which led him to abandon heart surgery and produced a generalized pessimism about extracorporeal circulation. However, a year later Walton Lillehei reverted this situation with the introduction of controlled cross-circulation in which a patient, usually a child, was connected to a "donor", usually his father or mother, whose heart and lung served as a pump and oxigenator, allowing the performance of open heart surgery. Finally, it was Lillehei again who a year later introduced the bubble oxigenator, simple and inexpensive, opening the doors of open heart surgery to all surgeons around the world. For this, and many other reasons, Walton Lillehei is considered by most surgeons as the "Father of Open Heart Surgery". Lillehei visited Chile in 1963 and operated on a patient in the surgical theaters of the Hospital Clínico de la Universidad Católica and was named an Honorary Member of the School of Medicine of this University. Before that, in 1957 Helmut Jaeger at the Hospital Luis Calvo Mackenna performed the first successful surgical closure of an atrial septal defect with extracorporeal circulation in Chile using a De Wall-Lillehei bubble oxigenator (Rev Méd Chile 2003; 131: 1337-44).

Revascularización coronaria sin circulación extracorpórea / Coronary revascularization without the use of extracorporeal circulation

Introducción: Se trata de un procedimiento diferente al tradicional porque es realizado mientras el corazón sigue latiendo. El cirujano no usa la máquina Corazón-Pulmón para el corazón durante el procedimiento. En vez de ésto el cirujano usa instrumentos para estabilizar el área destinada para colocar el injerto coronario. Esto permite continuar con el flujo de sangre coronario natural. Material y Métodos: En la Unidad de Cirugía Cardiovascular de Guatemala "UNICAR" de agosto de 1999 a enero 2002, 41 pacientes fueron operados de revascularización coronaria con este método con edades comprendidas entre 35 y 80 años, siendo más frecuente el grupo de 51 a 55 años. Resultados: El porcentaje de hemoductos realizados por paciente fue de 2.15 por ciento, utilizándose en todos arteria mamaria interna para revascularizar la descendente anterior. Se utilizó arteria radial en 2 casos. El promedio de estancia en el intensivo fue de 24 horas en el 72 por ciento. En el 82 por ciento no hubo ninguna complicación, 2 pacientes presentaron derrame pleural (4.87 por ciento). Cinco pacientes (12.19 por ciento) presentaron fallo cardíaco que resolvió en las primeras 48 horas. Un paciente desarrolló infarto del miocardio trans-operatorio sin ninguna repercusión hemodinámica (2.43 por ciento). La mortalidad fue del 4.87 por ciento (2 pacientes) que desarrollaron neumonía post-operatoria y el segundo hizo fallo multisistémico por sepsis de causas no cardíacas. Conclusiones: Este procedimiento reduce el trauma del músculo cardíaco y órganos blandos. La recuperación es rápida y disminuye la estadía hospitalaria. Reduce el riesgo de sangrado, accidente cerebrovascular y fallo renal. Reduce los problemas psicomotores y cognocitivos que se presentan con el método tradicional. Presenta poca morbi-mortalidad

The study of erythrocyte fragility and morphological changes caused by roller pump in vitro / 生物医学工程学杂志

To observe the erythrocyte fragility and morphological changes of erythrocytes caused by roller pump. Ten tests were divided into two groups, Polystan pediatric pump group A (n = 5) and COBE pump group B (n = 5). Ten whole blood samples (each 400 ml) were circulated in the roller pump for 16 h. Erythrocyte fragility and free hemoglobin were measured before pumping and at every 2 hours during pumping. The possible morphological changes of erythrocytes caused by roller pump were observed by scanning electron microscope. The electron microscopic observation was made before pumping and at every 4 hours throughout pumping. Results showed that the erythrocyte fragility of two groups was not increased during a long period of pumping. The number of acanthocytes of two groups was 1.77/1.81% in the samples before pumping and 6.12/7.13, 9.18/8.73, 13.21/12.89, 16.53/17.21% at 4 h, 8 h, 12 h, and 16 h respectively. The free hemoglobin level of two groups was increased linearly during a long duration of pumping and the index of hemolysis of two groups was 0.296 mg/L/h and 0.3993 mg/L/h respectively. The result shows: 1. the erythrocyte fragility was not increased during a long period of pumping; 2. the erythrocyte membrane was injured or broken by roller pump directly; 3. the morphological changes of erythrocytes would be the basis of post operative hemolysis.

Is off-pump coronary artery bypass surgery safe for left main coronary artery stenosis?

BACKGROUND: The feasibility of off-pump coronary artery bypass surgery has been well demonstrated. The purpose of the present study was to assess the safety and efficacy of off-pump coronary artery surgery in patients with left main coronary artery disease. METHODS AND RESULTS: Between January 1997 and December 2000, 174 patients with significant left main coronary artery stenosis underwent coronary artery bypass grafting without a pump. During the same period, 991 patients who also had significant left main coronary artery stenosis underwent coronary artery surgery on a pump. The patients in the two groups were matched in preoperative variables except that those in the off-pump group were slightly older, and more required urgent surgery. Hospital mortality was 2/174 and 21/991 in the off-pump and on-pump groups, respectively (p=0.560). The incidence of perioperative myocardial infarction (1.74 v. 14/991, p=0.712), atrial fibrillation (17/174 v 157/991, p=0.050) and blood transfusion requirement (63/174 v. 476/991, p=0.05) were significantly less in the off-pump group. The intubation time (15+/-3 hours v 22+/-4 hours, p=0.001), blood loss (365+/-61 ml v 582+/-76 ml, p<0.001), intensive care unit stay (23+/-10 hours v. 36+/-11 hours, p<0.001) and hospital stay (6+/-4 days v. 9+/-5 days, p <0.001) were also less in the off-pump group. CONCLUSIONS: Off-pump coronary artery bypass surgery is safe and effective for patients with left main coronary artery disease.

Controle automático de nível sangüíneo em osigenadores de circulação extracorpórea / Automatic blood level control for oxygenators used in extracorporeal circulation

Desde a primeira cirurgia cardíaca usando a técnica de circulação extracorpórea (CEG) em 1953, o avanço dos materiais e equipamentos e da própria técnica tem sido notável, reduzindo consideravelmente a ocorrência de acidentes relacionados à falhas mecânicas e/ou elétricas. Por outro lado, acidentes provocados por falha humana ainda ocorrem com certa freqüência, destacando-se a embolia aérea, na qual o reservatória de sangue do oxigenador esvazia-se em poucos segundos sem que o perfusionista perceba, resultando em uma injeção maciça de ar no paciente podendo deixá-lo com seqüelas graves ou levá-lo à morte. Visando aumentar a segurança da CEG e reduzir a possibilidade de ocorrência de embolia aérea provocada pelo esvaziamento acidental do oxigenador, foi desenvolvido um sistema de controle do nível de sangue no oxigenador que utiliza um sensor ultra-sônico e controla automaticamente a rotação da bomba sistêmica, além de acionar alarmes audiovisuais. Os resultados experimentais demonstraram a eficácia do equiapmento.

Cuidados en terapia intensiva de un paciente en asistencia biventricular como puente al trasplante cardiaco / Intensive care in a patient under biventricular assistance prior to cardiac transplantation

Masculino de 21 años, en insuficiencia multiorgánica consecutiva a cardiomiopatía dilatada extrema. Con el manejo farmacológico máximo tuvo sólo discreta mejoría y persistió con síndrome de bajo gasto acompañado de insuficiencia renal y hepática moderada. Se implantó un sistema neumático paracorpóreo de asistencia biventricular (Thoratec), posterior a lo cual se logró la resolución inmediata de la hipoperfusión sistémica y pudo iniciarse rápidamente su rehabilitación, egresando de la sala de cuidados intensivos siete días después. Durante el soporte mecánico ventricular tuvo sepsis por estafilococo y un episodio de isquemia cerebral resuelto ad intergrum. Se mantuvo en soporte biventricular satisfactorialmente durante 140 días, hasta su transplante ortotópico; el paciente falleció al segundo día posterior al trasplante o consecuencia de coagulopatia grave

Effect of High-dose Aprotinin on Postoperative Homologous Blood Requirement in Adult Cardiac Surgery / 대한마취과학회지

BACKGROUND: Post-CPB bleeding diathesis remains one of main causes of morbidity in open heart operation since it requires significant amount of homologous transfusion. Many approaches have been studied to reduce the amount of postoperative blood loss and blood use. Aprotinin is known to reduce postoperative bleeding. Therefore, hemostatic effects of aprotinin have been searched in open heart surgery. METHODS: Adult patients for open heart opeartion were randomly allocated to two groups, control group and study group. All anesthetic, surgical and bypass techniques were standardized. After induction, 10,000 KIU given for testing and then 2,000,000 KIU of aprotinin was infused for 20~30 minutes before sternotomy, and followed by at rate of 500,000 KIU/hr. Additional 2,000,000 KIU of aprotinin was mixed to pump prime of heart-lung machine. Aprotinin infusion was ended by the time of skin closure. Amount of postoperative bleeding as well as homologous blood requirement were measured. Urine output and serum creatinine were also documented during postoperative period. RESULTS: Postoperative-36hr summation of blood loss differed significantly(1858.4 1182.9 ml vs. 1256.7 688.4 ml, p<0.1). Postoperative homologous blood requirements were also reduced in the requirement of packed RBCs use(3.0 2.5 units vs. 1.0 0.8 units, p<0.01) and of fresh frozen plasma use(6.6 4.4 units vs. 3.9 2.6 units, p<0.05). Postoperative measurement of urine output and serum creatinine showed insignificant difference between groups while remained within normal range. CONCLUSIONS: High-dose aprotinin seems to have beneficial effect in reducing postoperative blood loss and blood use without renal complication.

Influence of Aprotinin on Kaolin and Celite on Activated Clotting Time in Cardiac Surgery / 대한마취과학회지

BACKGROUND: High-dose aprotinin appears to enhance the anticoagulant effects of heparin, as documented by increases in the activated clotting times (ACTs) during cardiopulmonary bypass. This increase of the ACT in the presence of aprotinin and heparin is due to the use of celite as surface activator. We compared celite and kaolin as surface activators for the measurement of the ACT in cardiac surgical patients treated with high dose aprotinin. METHODS: This study included 25 patients who were scheduled for coronary bypass graft surgery and reoperation of cardiac valvular surgery. The 2 million units of aprotinin were added to the pump prime of heart-lung machine. The dosage of heparin and protamine was 3 mg/kg respectively. Whole blood was sampled 10 minutes after induction, heparin administration, cardiopulmonary bypass(CPB), 10 minutes before the termination of CPB and 10 minutes after protamine administration. The ACT was measured with Hemochron 801 blood coagulation timer with 12 mg of either celite (C-ACT) or kaolin (K-ACT) used as surface activator. RESULTS: At 10 minutes after induction and heparin administration, celite and kaolin ACTs were l20+/-28, 541+/-247 seconds and 126+/-23, 559+/-267 seconds rcspectively. But 10 minutes after initiation of CPB and before the termination of CPB, celite ACTs were 941+/-238 and 787+/-277 seconds; kaolin ACTs were 605+/-182 and 499+65 seconds, which were consistently less than celite ACTs(p<0.01). At 10 minutes after protamine administration, celite ACT was 118+/-12 seconds and kaolin ACT was 142 56 seconds which was consistently more than celite ACT(p<0.05). CONCLUSIONS: We recommend the K-ACT rather than C-ACT when monitoring of heparin-induced anticoagulation in patients treated with high-dose aprotinin. It is also highly recommended that patients being added with aprotinin should receive the usual doses of heparin and that the ACT should be measured with kaolin as the activator.

Influence of Aprotinin on Kaolin and Celite on Activated Clotting Time in Cardiac Surgery / 대한마취과학회지

BACKGROUND: High-dose aprotinin appears to enhance the anticoagulant effects of heparin, as documented by increases in the activated clotting times (ACTs) during cardiopulmonary bypass. This increase of the ACT in the presence of aprotinin and heparin is due to the use of celite as surface activator. We compared celite and kaolin as surface activators for the measurement of the ACT in cardiac surgical patients treated with high dose aprotinin. METHODS: This study included 25 patients who were scheduled for coronary bypass graft surgery and reoperation of cardiac valvular surgery. The 2 million units of aprotinin were added to the pump prime of heart-lung machine. The dosage of heparin and protamine was 3 mg/kg respectively. Whole blood was sampled 10 minutes after induction, heparin administration, cardiopulmonary bypass(CPB), 10 minutes before the termination of CPB and 10 minutes after protamine administration. The ACT was measured with Hemochron 801 blood coagulation timer with 12 mg of either celite (C-ACT) or kaolin (K-ACT) used as surface activator. RESULTS: At 10 minutes after induction and heparin administration, celite and kaolin ACTs were l20+/-28, 541+/-247 seconds and 126+/-23, 559+/-267 seconds rcspectively. But 10 minutes after initiation of CPB and before the termination of CPB, celite ACTs were 941+/-238 and 787+/-277 seconds; kaolin ACTs were 605+/-182 and 499+65 seconds, which were consistently less than celite ACTs(p<0.01). At 10 minutes after protamine administration, celite ACT was 118+/-12 seconds and kaolin ACT was 142 56 seconds which was consistently more than celite ACT(p<0.05). CONCLUSIONS: We recommend the K-ACT rather than C-ACT when monitoring of heparin-induced anticoagulation in patients treated with high-dose aprotinin. It is also highly recommended that patients being added with aprotinin should receive the usual doses of heparin and that the ACT should be measured with kaolin as the activator.

The Influence of isoflurane on systemic vascualr resistance during cardiopulmonary bypass / 대한마취과학회지

The influence of isoflurane on systemic vascular resistances was studied during total cardiopulmonary bypass with membrane oxygenator, low rate of 2.4 L/min/m(2) and moderate hypothermia Data were obtained from 40 adult patients undergoing corrective surgery for congenital or aquired heart disease. The materials were randomly divided in two groups with 20 and 20 patients, respectively, Before cadiopulmonary bypass, the same anesthetic technique was applied to 2 groups. During cardiapuhnonary bypass, isoflurane was given into oxygenator at 0.5-1.5% concentration in group I. In group II, no isoflurane was given but 0.2 mg/kg midazolam was supplied into the oxygenator at the beginning of bypass. To both groups small amounts of fentanyl were given during bypass. There were no significant differences in mean cardiopulmonary bypass time and pump flow between the groups.In group I, systemic vascular resistance did not increase until 60 minutes, whereas in group II systemic vascular resistance increased significantly after 30 minutes and maximal increase was noticed at 60 minutes. Data for base excess demonstrated that significant fall after 40 minutes of perfusion in group II, but not changes in group I. It is concluded that isoflurane exerts a beneficial vasodilatory action during caardiopulmonary bypass and hypothermia. And the harzards of local reduction in organic blood flow are ehminated, because an adequate perfusion pressure and flow are maintained by the heart lung machine.