cardiopulmonary bypass (cpb) circuit setup for cardiac arrest and resuscitation in pediatric animal model

Reanimación cardiopulmonar extracorpórea en modelo animal tras un paro cardiaco

Congenital heart disease (CHD) is the most prevalent congenital malformation, with about one million births impacted&#160;worldwide per year1. Though modern advances in cardiothoracic surgery (CTS) and intensive care treatment have improved mortality rates, comorbidities remain extremely common2,3,4,5. Neurodevelopmental abnormalities, including cognitive and motor impairments as well as learning disabilities, are reported in around 25%-50% of these patients6,7,8. Surgery during the first days of life, especially those that require circulatory and cardiac arrest (CA), has been demonstrated to increase morbidity9. Hemodynamic alterations during surgery may have an important effect on the vulnerable developing newborn brain. Experimental models are essential to better understand the origin of these abnormalities and investigate neuroprotective strategies to improve the prognoses of these patients.
The use of animal models to study this population has been widely documented5,10,11,12,13,14. Notably, piglets offer an excellent option, given close approximations in cardiac anatomy (Figure 1), genome, and physiology, as well as their relatively larger size in comparison to other animal models15 (Figure 2). The use of piglet models to study the effects of both cardiopulmonary bypass (CPB) and CA has been previously described. These experimental animal models are useful for studying hemodynamic changes and associated end-tissue organ complications14,16,17,18,19,20. These models were developed to allow researchers to study human conditions in a controlled setting, with flexibility for a variety of experimental conditions. Most studies report the use of central cannulation, a technique that demands advanced surgical skills, requires higher resource utilization, and makes it difficult to ensure long-term survival. Though previous studies have documented the use of piglets in studying CPB12,15, few have proposed the peripheral cannulation technique.
This new peripheral cannulation technique is easier, less aggressive, and more feasible when compared to other published studies19. Moreover, validating this technique in newborns and small animals is novel and should be considered for use by all researchers interested in using an animal model to study CHD and its associated comorbidities. It is particularly appropriate for individuals with access to a laboratory equipped with supplies, resources, and personnel experienced in conducting animal model experiments.
In summary, the main aim of this study is to describe and validate a neonatal piglet model of CPB with CA. The protocol aims to study severe brain damage and other possible complications of CPB surgery in a controlled setting with varying experimental conditions. This method provides a model that is generalizable, reliable, and of high quality, which can be used for a wide variety of experimental protocols.

Autor destacado: Simulación de cirugía cardíaca pediátrica mediante un modelo de lechones neonatos

Modelo animal pediátrico de reanimación cardiopulmonar extracorpórea tras parada circulatoria prolongada

Mortality rates for children with congenital heart defects have improved significantly in recent years given improvements in cardiac surgery. However, comorbidities remain extremely common, and that's the goal of our lab. We aim to investigate these comorbidities, uncover underlying causes, and develop preventative measures.Right now, we are studying neuro abnormalities that develop after cardiac surgery. This protocol offers a feasible and reproducible animal model of simulating pediatric cardiac surgery. So with that, researchers can use it as a base to test many different experimental conditions and a wide variety of other hypotheses.The peripheral cannulation technique for porcine cardiopulmonary bypass in our model is both practical and cost effective. Furthermore, it does allow a more reliable way to assess postoperative outcomes than the traditional central cannulation technique. The flexibility of our model encourages future work in congenital heart disease and comorbidity studies.For example, our lab is currently planning to expand this model to study real-time monitoring of cerebral parameters such as oxygenation status and cerebral blood flow.

Configuración del circuito de derivación cardiopulmonar (CPB) para paro cardíaco y reanimación en un modelo animal pediátrico

Para comenzar, coloque al lechón anestesiado de cuatro a seis días de edad en la posición dorsal recostada. Después de realizar la intubación orotraqueal con un tubo con manguito, auscultar las bases pulmonares para confirmar la colocación adecuada del tubo endotraqueal. Configure la ventilación mecánica y controle continuamente la profundidad de la anestesia durante la cirugía a través de la frecuencia cardíaca, la presión arterial y la saturación de oxígeno.Ajuste los parámetros ventilatorios y de sedación según sea necesario. A continuación, inserte un catéter de 3 French en la arteria femoral, seguido de un catéter de 4 French en la vena. A continuación, inicie el circuito de derivación cardiopulmonar, o CPB, acortando el tubo de CPB mientras mantiene suficiente distancia entre el animal y la máquina.Cree un puente de tubería para conectar el flujo de salida del oxigenador de membrana y el flujo de entrada de la bomba. Una vez que todos los puntos de conexión estén sellados, barre el circuito con 300 microlitros de solución salina de heparina y 300 mililitros de sangre fresca de cerdo donante, seguido de bicarbonato de sodio, heparina y gluconato de calcio. Una vez que el circuito de CPB esté listo, exponga la vena yugular interna izquierda e inserte el catéter de aguja en ella.Del mismo modo, exponga la arteria carótida derecha para prepararse para la canulación. Una vez que se vea un destello de sangre, inserte con cuidado un alambre guía en el vaso. Enrosque un dilatador sobre el alambre y dentro del recipiente.A continuación, retire el dilatador. Introduzca lentamente una cánula venosa francesa de aproximadamente cuatro centímetros en el vaso y retire el alambre, asegurándose de que la cánula permanezca en su lugar. A continuación, coloque una cánula arterial pediátrica francesa 6 en la arteria carótida derecha como se demostró anteriormente con la dilatación.Por último, administrar un bolo de heparina intravenosa a través de la cánula arterial recién colocada. Después de lograr el acceso, use suturas absorbibles 3-0 para fijar ambas cánulas al animal y cinta adhesiva para evitar la extracción inadvertida. Conecte las cánulas al circuito CPB, asegurándose de que se agregue solución salina de heparina a los puntos de conexión para evitar que entre aire en el circuito.Ajuste el flujo inicial a 80 a 85 mililitros por kilogramo por minuto. Para inducir un paro cardíaco, administre nueve miliequivalentes de cloruro de potasio. Una vez que el corazón se detiene, aísla al animal del circuito.Luego mantenga el flujo del circuito CPB para que circule a 1, 500 RPM. Después de lograr las condiciones adecuadas de paro cardíaco, comience la reanimación cardiopulmonar extracorpórea volviendo a conectar el lechón al circuito de CPB. Administrar tres mililitros de gluconato de calcio y seis mililitros de bicarbonato de sodio a través del acceso arterial periférico, añadiendo dosis según sea necesario.La canulación de vasos y la CEC con paro cardíaco lograron una tasa de éxito del 92% en los experimentos. Las resonancias magnéticas demostraron signos claros de daño cerebral temprano en los animales con paro cardíaco en comparación con el control. La modalidad de imagen con tensor de difusión aguda identificó mejor los signos de infarto que otras secuencias de resonancia magnética convencionales.

Research

JoVE Journal

Medicine

Cardiopulmonary Bypass (CPB) Circuit Setup for Cardiac Arrest and Resuscitation in Pediatric Animal Model

Pediatric Animal Model of Extracorporeal Cardiopulmonary Resuscitation After Prolonged Circulatory Arrest

Congenital heart disease (CHD) is the most prevalent congenital malformation, with about one million births impacted worldwide per year. Comprehensive ...

Investigación

Medicina