This protocol describes a neonatal porcine model of cardiopulmonary bypass (CPB), with circulatory and cardiac arrest as a tool for studying severe brain damage and other complications secondary to CPB.
Congenital heart disease (CHD) is the most prevalent congenital malformation, with about one million births impacted worldwide per year. Comprehensive investigation of this disease requires appropriate and validated animal models. Piglets are commonly used for translational research due to their analogous anatomy and physiology. This work aimed to describe and validate a neonatal piglet model of cardiopulmonary bypass (CPB) with circulatory and cardiac arrest (CA) as a tool for studying severe brain damage and other complications of cardiac surgery. In addition to including a list of materials, this work provides a roadmap for other investigators to plan and execute this protocol. After experienced practitioners performed several trials, the representative results of the model demonstrated a 92% success rate, with failures attributed to small piglet size and variant vessel anatomy. Furthermore, the model allowed practitioners to select from a wide variety of experimental conditions, including varying times in CA, temperature alterations, and pharmacologic interventions. In summary, this method uses materials readily available in most hospital settings, is reliable and reproducible, and can be widely employed to enhance translational research in children undergoing heart surgery.
Congenital heart disease (CHD) is the most prevalent congenital malformation, with about one million births impacted 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.
Cardiopulmonary bypass is commonly used during cardiac surgery for adults, children, and neonates. It relies on a motorized extracorporeal circuit and membrane oxygenator that work together to oxygenate blood and provide pulmonary and cardiac stabilization. Previous studies have demonstrated that CPB may adversely impact many organ systems (renal, cerebral, pulmonary, cardiac, gastrointestinal) both in ill and formerly healthy patients22,23,<sup class=…
The authors have nothing to disclose.
This project has received funding from the European Union's Horizon 2020 research and innovation program under grant agreement no 101017113, Instituto de Salud Carlos III (PI20/00298), Beca Carmen de Torres (Fundació Sant Joan de Déu), and the Vanderbilt Medical Scholars Program. We thank all the staff of CMCiB, including Jordi Grifols, María del Mar Arevalo, Juan Ricardo Gonzalez, Sara Capdevila, Josep Puig, and Gemma Cristina Monte Rubi). We also give special thanks to Abril Culell Camprubí and Dr. Sergi Cesar Díaz for their assistance in anatomical drawings.
1.5% sevofluorane | Zoetis | 20070289 | |
2.5 mm endotracheal tube | Henry Schein | 988-1782 | |
3 Fr catheter for peripheral arterial access | Prodimed | 3872.1 | |
4 Fr catheter for peripheral venous access | Prodimed | 3872.13 | |
6 French ECMO pediatric arterial cannula | Medtronic | 77206 | |
8 French ECMO pediatric venous cannula | Medtronic | 68112 | |
Adrenaline | B Braun | 469801-1119 | |
Adson forceps | Allgaier instruments | 08-030-130 | Any brand may be substituted |
BP cuff | Mindray | ||
Buprenorfine (0.01 mg/kg) | Richter Pharma | #9004114000537 | |
Calcium gluconate (2.25 mmol/10 mL) | B Braun | 570-12606194-1119 | |
Dexmedetomidine (0.5-2.0 µg/kg/min) | Orion farma | GTN 064321000017253 | |
Dolethol | vetoquinol | #3605870004904 | |
Dopamine | hikma | A044098010 | |
Fentanyl (25-200 µg/kg/min) | Kern Pharma | 756650.2H | |
Fresh donor pig blood Type O | Any | ||
Heat Exchanger | Maquet Gmbh & Co | MCP70107.2130 | |
Heparin (1350 UI) | ROVI | 641641.1 | |
Irwin retractor | Aesculap | BV104R | Any brand may be substituted |
Ketamine (20 mg/kg) | Richter Pharma | #9004114000452 | |
Lubricant | Any orotracheal lubricant | ||
Midazolam (0.3 mg/kg) | Serra Pamies | 619627.4 | |
Mosquito forceps | Aesculap | BH109R | Any brand may be substituted |
Needle forceps | Aesculap | BM016R | Any brand may be substituted |
Normal saline (0.9%) | B Braun Fisiovet | 5/469827/0610 | Any brand may be substituted |
Plastic clamps for tubing | Achim Schulz-Lauterbach | DBGM | Any brand may be substituted |
Potassium chloride (9 mEq) | B Braun | 3545156 | |
Propofol (0.5 mg/kg) | Zoetis | 579742.7 | |
Quadrox Membrane Oxygenator | Maquet Gmbh & Co | BE-HMOSD 300000 | |
Rectal thermometer | Any | ||
RotaFlow Console ECMO system | Maquet Gmbh & Co | MCP00703177 | Neonatal ECMO System |
Scalpel | Aesculap | BB074R | Any brand may be substituted |
Sodium bicarbonate (1 M) | Fresenius Kabi | 634477.4 OH | |
Surgical scissors | Talmed Inox | 112 | Any brand may be substituted |
Suture (3/0 poly absorbable) | B Braun Novosyn (R) | 0068030N1 | Any brand may be substituted |