The authors would like to acknowledge Dr. Wanchun Tang MD, MCCM, FCCP, FAHA and Jena Cahoon of the Weil Institute of Critical Care Medicine in Rancho Mirage, CA. for their contributions to the resuscitation protocol outline and for having helped train the rodent surgeon (LL). The preparation of this article was in part supported by a gift in memory of US Navy Retired SKC Robert W. Ply by Ms. Monica Ply for research in heart disease and Parkinson&#8217;s disease and by a discretionary fund from the Department of Medicine at Rosalind Franklin University of Medicine and Science.

The authors have nothing to disclose.

Passos críticos no protocolo Há passos críticos no protocolo. Quando dominado, a preparação e protocolo proceda como sucintamente descrito abaixo. A preparação cirúrgica é célere, avançando rapidamente cateteres através de pequenas incisões provocando espasmos mínimo ou nenhum navio e posicionando as pontas dos cateteres como pretendido, seguido de intubação traqueal com sucesso após uma única ou poucas tentativa (s); assim, completando a preparação em ≈ 90 min...

Perto de 360 mil pessoas nos Estados Unidos 1 e muitos mais em todo o mundo 2 sofrem um episódio de parada cardíaca súbita a cada ano. As tentativas de restaurar a vida não apenas exigem que a atividade cardíaca ser restabelecida, mas que os danos aos órgãos vitais ser prevenida, minimizado ou revertido. Técnicas de ressuscitação cardiopulmonar atuais produzir uma taxa de reanimação inicial de aproximadamente 30%; no entanto, a sobrevivência à alta hospitalar é de apenas 5% 1. A disfunção miocárdica, disfunção neurológica, inflamação sistêmica, doenças intercorrentes, ou uma combinação destes se conta pós-ressuscitação para a grande proporção de pacientes que morrem apesar de retorno inicial de circulação. Assim, uma maior compreensão da fisiopatologia e da novela de reanimação abordagens subjacentes são urgentemente necessárias para aumentar a taxa de ressuscitação inicial e subsequente sobrevivência com a função do órgão intacto. Modo de animalls de parada cardíaca desempenham um papel crítico no desenvolvimento de novas terapias de reanimação, fornecendo conhecimentos sobre a fisiopatologia da parada cardíaca e ressuscitação e oferecendo meios práticos para conceituar e testar novas intervenções antes que possam ser testada em seres humanos 3. O modelo de rato de peito fechado ressuscitação cardiopulmonar (CPR) descrito aqui tem desempenhado um papel importante. O modelo foi desenvolvido em 1988 por Irene von Planta - um bolseiro de investigação na época - e seus colaboradores 4 no laboratório do falecido professor Max Harry Weil MD, Ph.D. da Universidade de Ciências da Saúde (rebatizada Rosalind Franklin Universidade de Medicina e Ciência em 2004) e tem sido amplamente utilizada no campo da reanimação predominantemente por companheiros de Professor Weil e seus estagiários. O modelo simula um episódio de parada cardíaca súbita com ressuscitação tentada por técnicas de RCP convencional e inclui, assim, indutoion de fibrilação ventricular (FV), fornecendo uma corrente elétrica para o endocárdio do ventrículo direito e prestação de CPR peito fechado por um dispositivo de pistão pneumaticamente enquanto concomitantemente entrega de ventilação com pressão positiva com o gás rico em oxigênio. Rescisão do VF é realizado pela entrega transtorácica de choques elétricos. O modelo de rato estabelece um equilíbrio entre os modelos desenvolvidos em animais de grande porte (por exemplo, suínos) e modelos desenvolvidos em animais menores (por exemplo, os ratos) permitindo a exploração de novos conceitos de investigação de uma forma bem padronizado, reprodutível e eficiente, com acesso a um robusto inventário das medições pertinentes. O modelo é particularmente útil nos estágios iniciais de pesquisa para explorar novos conceitos e examinar os efeitos de fatores de confusão antes de realizar estudos em modelos animais maiores, que são mais caros, mas de maior impacto translacional. A pesquisa Medline para todos os artigos revisados ​​por pares de apresentação, conformemodelo de rato imilar ter VF como o mecanismo de parada cardíaca e alguma forma de reanimação peito fechado revelou um total de 69 estudos originais adicionais utilizando o modelo desde que foi publicado pela primeira vez em 1988 4. As áreas de pesquisa incluem aspectos fisiopatológicos da reanimação 5-17, fatores que influenciam os resultados 18-30, o papel das intervenções farmacológicas que examinam agentes vasoconstritores 31-43, agentes tampão 44, inotrópicos 45, agentes que visam a proteção do miocárdio ou cerebral 46-70, e também os efeitos das células-tronco mesenquimais 71-73. O modelo e protocolo descrito neste artigo está sendo usado atualmente no Instituto de Ressuscitação. No entanto, existem várias oportunidades para &quot;personalizar&quot; o modelo com base nos recursos disponíveis para os investigadores e os objetivos dos estudos.

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			<td height="42" style="height:42px;width:216px;">Name of Material/ Equipment</td>
			<td style="width:93px;">Company</td>
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			<td style="width:167px;">Comments/Description</td>
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			<td height="84" style="height:84px;width:216px;">Sodium pentobarbital</td>
			<td style="width:93px;">Sigma Aldrich</td>
			<td style="width:119px;">P3761</td>
			<td style="width:167px;">http://www.sigmaaldrich.com/catalog/product/sigma/p3761?lang=en&#38;region=US</td>
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		<tr height="63">
			<td height="63" style="height:63px;width:216px;">Rectal thermistor</td>
			<td style="width:93px;">BIOPAC Systems, INC</td>
			<td style="width:119px;">TSD202A</td>
			<td style="width:167px;">http://www.biopac.com/fast-response-thermistor</td>
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			<td height="63" style="height:63px;width:216px;">Needle electrode biopolar concentric 25 mm TP</td>
			<td style="width:93px;">BIOPAC Systems, INC</td>
			<td style="width:119px;">EL451</td>
			<td style="width:167px;">http://www.biopac.com/needle-electrode-concentric-25mm</td>
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			<td height="63" style="height:63px;width:216px;">PE25 polyethylene tubing&#160;</td>
			<td style="width:93px;">Solomon Scientific</td>
			<td style="width:119px;">BPE-T25</td>
			<td style="width:167px;">http://www.solsci.com/products/polyethylene-pe-tubing</td>
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		<tr height="63">
			<td height="63" style="height:63px;width:216px;">26GA female luer stub adapter</td>
			<td style="width:93px;">Access Technologies</td>
			<td style="width:119px;">LSA-26</td>
			<td style="width:167px;">http://www.norfolkaccess.com/needles.html</td>
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		<tr height="105">
			<td height="105" style="height:105px;width:216px;">Stopcocks with luer connections; 3-way; male lock, non-sterile</td>
			<td style="width:93px;">Cole-Parmer</td>
			<td style="width:119px;">UX-30600-02</td>
			<td style="width:167px;">http://www.coleparmer.com/Product/Large_bore_3_way 
			_male_lock_stopcocks 
			_10_pack_Non_sterile/EW-30600-23</td>
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		<tr height="84">
			<td height="84" style="height:84px;width:216px;">TruWave disposable pressure transducer</td>
			<td style="width:93px;">Edwards Lifesciences</td>
			<td style="width:119px;">PX600I&#160;</td>
			<td style="width:167px;">http://www.edwards.com/products/pressuremonitoring/Pages/truwavemodels.aspx?truwave=1</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:216px;">Type-T thermocouple</td>
			<td style="width:93px;">Physitemp Instruments</td>
			<td style="width:119px;">IT-18</td>
			<td style="width:167px;">http://www.physitemp.com/products/probesandwire/flexprobes.html</td>
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		<tr height="84">
			<td height="84" style="height:84px;width:216px;">Central venous pediatric catheter&#160;</td>
			<td style="width:93px;">Cook Medical&#160;</td>
			<td style="width:119px;">C-PUM-301J</td>
			<td style="width:167px;">https://www.cookmedical.com/product/-/catalog/display?ds=cc_pum1lp_webds</td>
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		<tr height="63">
			<td height="63" style="height:63px;width:216px;">Abbocath-T subclavian I.V. catheter (14g x 5 1/2&#34;)</td>
			<td style="width:93px;">Hospira</td>
			<td style="width:119px;">453527</td>
			<td style="width:167px;">http://www.hospira.com/products_and_services/iv_sets/045350427</td>
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		<tr height="105">
			<td height="105" style="height:105px;width:216px;">Novametrix Medical Systems, Infrared CO2 monitor</td>
			<td style="width:93px;">Soma Technology, Inc.</td>
			<td style="width:119px;">7100 CO2SMO&#160;</td>
			<td style="width:167px;">http://www.somatechnology.com/MedicalProducts/novametrix_respironics_co2smo_ 
			7100.asp</td>
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		<tr height="147">
			<td height="147" style="height:147px;width:216px;">Harvard Model 683 small animal ventilator</td>
			<td style="width:93px;">Harvard Apparatus</td>
			<td style="width:119px;">555282</td>
			<td style="width:167px;">http://www.harvardapparatus.com/webapp/wcs/stores/servlet/haisku2_10001_11051_44453_-1_ 
			HAI_ProductDetail_N_37322_37323</td>
		</tr>
		<tr height="84">
			<td height="84" style="height:84px;width:216px;">Double-flexible tipped wire guides</td>
			<td style="width:93px;">Cook Medical&#160;</td>
			<td style="width:119px;">C-DOC-15-40-0-2</td>
			<td style="width:167px;">https://www.cookmedical.com/product/-/catalog/display?ds=cc_doc_webds</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">High accuracy AC LVDT displacement sensor</td>
			<td style="width:93px;">Omega Engineering</td>
			<td style="width:119px;">LD320-25</td>
			<td style="width:167px;">http://www.omega.com/pptst/LD320.html</td>
		</tr>
		<tr height="84">
			<td height="84" style="height:84px;width:216px;">HeartStart XL defibrillator/monitor</td>
			<td style="width:93px;">Phillips Medical Systems</td>
			<td style="width:119px;">M4735A</td>
			<td style="width:167px;">http://www.healthcare.philips.com/main/products/resuscitation/products/xl/</td>
		</tr>
		<tr height="105">
			<td height="105" style="height:105px;width:216px;">Graefe micro dissection forceps 4 inches</td>
			<td style="width:93px;">Roboz&#160;</td>
			<td style="width:119px;">RS-5135</td>
			<td style="width:167px;">http://shopping.roboz.com/Surgical-Instrument-Online-Shopping?search=RS-5135</td>
		</tr>
		<tr height="105">
			<td height="105" style="height:105px;width:216px;">Graefe micro dissection forceps 4 inches with teeth</td>
			<td style="width:93px;">Roboz&#160;</td>
			<td style="width:119px;">RS-5157</td>
			<td style="width:167px;">http://shopping.roboz.com/Surgical-Instrument-Online-Shopping?search=RS-5157</td>
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		<tr height="147">
			<td height="147" style="height:147px;width:216px;">Extra fine micro dissection scissors 4 inches</td>
			<td style="width:93px;">Roboz&#160;</td>
			<td style="width:119px;">RS-5882</td>
			<td style="width:167px;">http://shopping.roboz.com/micro-scissors-micro-forceps-groups/micro-dissecting-scissors/Micro-Dissecting-Scissors-4-Straight-Sharp-Sharp</td>
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		<tr height="105">
			<td height="105" style="height:105px;width:216px;">Heiss tissue retractor</td>
			<td style="width:93px;">Fine Science Tools&#160;</td>
			<td style="width:119px;">17011-10</td>
			<td style="width:167px;">http://www.finescience.com/Special-Pages/Products.aspx?ProductId=321&#38;CategoryId=134&#38; 
			lang=en-US</td>
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		<tr height="84">
			<td height="84" style="height:84px;width:216px;">Crile curve tip hemostats</td>
			<td style="width:93px;">Fine Science Tools&#160;</td>
			<td style="width:119px;">13005-14</td>
			<td style="width:167px;">http://www.finescience.com/Special-Pages/Products.aspx?ProductId=372</td>
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		<tr height="63">
			<td height="63" style="height:63px;width:216px;">Visistat skin stapler&#160;</td>
			<td style="width:93px;">Teleflex Incorporated</td>
			<td style="width:119px;">528135</td>
			<td style="width:167px;">http://www.teleflexsurgicalcatalog.com/weck/products/9936</td>
		</tr>
		<tr height="147">
			<td height="147" style="height:147px;width:216px;">Braided silk suture, 3-0</td>
			<td style="width:93px;">Harvard Apparatus</td>
			<td style="width:119px;">517706</td>
			<td style="width:167px;">http://www.harvardapparatus.com/webapp/wcs/stores/servlet/haisku2_10001_11051_43051_-1_ 
			HAI_ProductDetail_N_37916_37936</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Betadine solution</td>
			<td style="width:93px;">Butler Schein</td>
			<td style="width:119px;">3660</td>
			<td style="width:167px;">https://www.henryscheinvet.com/</td>
		</tr>
		<tr height="84">
			<td height="84" style="height:84px;width:216px;">Sterile saline, 250 ml bags</td>
			<td style="width:93px;">Fisher</td>
			<td style="width:119px;">50-700-069</td>
			<td style="width:167px;">http://www.fishersci.com/ecomm/servlet/itemdetail?catnum=50700069&#38;storeId=10652</td>
		</tr>
		<tr height="84">
			<td height="84" style="height:84px;width:216px;">Heparin sodium injection, USP</td>
			<td style="width:93px;">Fresenius Kabi</td>
			<td style="width:119px;">504201</td>
			<td style="width:167px;">http://fkusa-products-catalog.com/files/assets/basic-html/page25.html</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Loxicom (meloxicam)</td>
			<td style="width:93px;">Butler Schein</td>
			<td style="width:119px;">045-321</td>
			<td style="width:167px;">https://www.henryscheinvet.com/</td>
		</tr>
		<tr height="105">
			<td height="105" style="height:105px;width:216px;">Thermodilution cardiac output computer for small animals</td>
			<td style="width:93px;">N/A</td>
			<td style="width:119px;">N/A</td>
			<td style="width:167px;">Custom-developed at the Resuscitation Institute using National Instruments hardware and LabVIEW software</td>
		</tr>
		<tr height="105">
			<td height="105" style="height:105px;width:216px;">Analog-to-digital data acquisition and analysis system</td>
			<td style="width:93px;">N/A</td>
			<td style="width:119px;">N/A</td>
			<td style="width:167px;">Custom-developed at the Resuscitation Institute using National Instruments hardware and LabVIEW software</td>
		</tr>
		<tr height="84">
			<td height="84" style="height:84px;width:216px;">Pneumatically-driven and electronically controlled piston device for chest compression in small animals</td>
			<td style="width:93px;">N/A</td>
			<td style="width:119px;">N/A</td>
			<td style="width:167px;">Custom-developed at the Weil Institute of Critical Care Medicine</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:216px;">60 Hz alternating current generator</td>
			<td style="width:93px;">N/A</td>
			<td style="width:119px;">N/A</td>
			<td style="width:167px;">Custom-developed at the Weil Institute of Critical Care Medicine</td>
		</tr>
	</tbody>
</table>

a rat model of ventricular fibrillation and resuscitation by conventional closed-chest technique

A rat model of electrically-induced ventricular fibrillation followed by cardiac resuscitation using a closed chest technique that incorporates the basic components of cardiopulmonary resuscitation in humans is herein described. The model was developed in 1988 and has been used in approximately 70 peer-reviewed publications examining a myriad of resuscitation aspects including its physiology and pathophysiology, determinants of resuscitability, pharmacologic interventions, and even the effects of cell therapies. The model featured in this presentation includes: (1) vascular catheterization to measure aortic and right atrial pressures, to measure cardiac output by thermodilution, and to electrically induce ventricular fibrillation; and (2) tracheal intubation for positive pressure ventilation with oxygen enriched gas and assessment of the end-tidal CO2. A typical sequence of intervention entails: (1) electrical induction of ventricular fibrillation, (2) chest compression using a mechanical piston device concomitantly with positive pressure ventilation delivering oxygen-enriched gas, (3) electrical shocks to terminate ventricular fibrillation and reestablish cardiac activity, (4) assessment of post-resuscitation hemodynamic and metabolic function, and (5) assessment of survival and recovery of organ function. A robust inventory of measurements is available that includes &#8211; but is not limited to &#8211; hemodynamic, metabolic, and tissue measurements. The model has been highly effective in developing new resuscitation concepts and examining novel therapeutic interventions before their testing in larger and translationally more relevant animal models of cardiac arrest and resuscitation.

O modelo de rato aqui descrito foi recentemente utilizado para comparar os efeitos de dois inibidores do trocador isoform sarcolemal sódio-hidrogênio 1 (NHE-1) sobre a função miocárdica e hemodinâmica durante a compressão torácica e pós-ressuscitação 61. Foi previamente relatado que NHE-1 inibidores de atenuar a lesão de reperfusão do miocárdio, limitando cytosolic induzida por sobrecarga de sódio e de cálcio mitocondrial e, assim, ajudar a preservar a distensibilidade ventricular esquerda dur...

Watch this Scientific Journal Video about A Rat Model of Ventricular Fibrillation and Resuscitation by Conventional Closed-chest Technique at JoVE.com

A Rat Model of Ventricular Fibrillation and Resuscitation by Conventional Closed-chest Technique

This article describes a rat model of electrically-induced ventricular fibrillation and resuscitation by chest compression, ventilation, and delivery of electrical shocks that simulates an episode of sudden cardiac arrest and conventional cardiopulmonary resuscitation. The model enables gathering insights on the pathophysiology of cardiac arrest and exploration of new resuscitation strategies.

Um modelo de rato de Fibrilação Ventricular e Reanimação por Técnica de tórax fechado convencional

A rat model of electrically-induced ventricular fibrillation followed by cardiac resuscitation using a closed chest technique that incorporates the basic ...

a-rat-model-ventricular-fibrillation-resuscitation-conventional

Research

JoVE Journal

Medicine

15.8K visualizações.  Rosalind Franklin University of Medicine and Science. This article describes a rat model of electrically-induced ventricular fibrillation and resuscitation by chest compression, ventilation, and delivery of electrical shocks that simulates an episode of sudden cardiac arrest and conventional cardiopulmonary resuscitation. The model enables gathering insights on the pathophysiology of cardiac arrest and exploration of new resuscitation strategies.

Vídeo: A Rat Model of Ventricular Fibrillation and Resuscitation by Conventional Closed-chest Technique

Normothermic Cardiac Arrest and Cardiopulmonary Resuscitation: A Mouse Model of Ischemia-Reperfusion Injury

Acute Kidney Injury (AKI) is a common, highly lethal, complication of critical illness which has a high mortality1-4 and which is most 
frequently caused by whole-body hypoperfusion.5,6 Successful reproduction of whole-body hypoperfusion in rodent models has been fraught with 
difficulty.7-9,9,10 Models which employ focal ischemia have repeatedly demonstrated results which do not translate to the clinical setting, and larger 
animal models which allow for whole body hypoperfusion lack access to the full toolset of genetic manipulation possible in the mouse.11,12 However, in recent 
years a mouse model of cardiac arrest and cardiopulmonary resuscitation has emerged which can be adapted to model AKI.13 This model reliably reproduces 
physiologic, functional, anatomic, and histologic outcomes seen in clinical AKI, is rapidly repeatable, and offers all of the significant advantages of a murine surgical 
model, including access to genetic manipulative techniques, low cost relative to large animals, and ease of use. Our group has developed extensive experience 
with use of this model to assess a number of organ-specific outcomes in AKI.14,15

A powerful model for perioperative and critical care related acute kidney injury is presented. Using whole body hypoperfusion induced by cardiac arrest it is possible to nearly replicate the histologic and functional changes of clinical AKI.

Cardiac Arrest normotérmica e Ressuscitação Cardiopulmonar: um modelo do rato de isquemia-reperfusão

Acute Kidney Injury (AKI) is a common, highly lethal, complication of critical illness which has a high mortality1-4 and which is most 
frequently caused ...

Medicina

A Murine Closed-chest Model of Myocardial Ischemia and Reperfusion

Surgical trauma by thoracotomy in open-chest models of coronary ligation induces an immune response which modifies different mechanisms involved in ischemia and reperfusion. Immune response includes cytokine expression and release or secretion of endogenous ligands of innate immune receptors. Activation of innate immunity can potentially modulate infarct size. We have modified an existing murine closed-chest model using hanging weights which could be useful for studying myocardial pre- and postconditioning and the role of innate immunity in myocardial ischemia and reperfusion. This model allows animals to recover from surgical trauma before onset of myocardial ischemia.
Volatile anesthetics have been intensely studied and their preconditioning effect for the ischemic heart is well known. However, this protective effect precludes its use in open chest models of coronary artery ligation. Thus, another advantage could be the use of the well controllable volatile anesthetics for instrumentation in a chronic closed-chest model, since their preconditioning effect lasts up to 72 hours. Chronic heart diseases with intermittent ischemia and multiple hit models are other possible applications of this model.
For the chronic closed-chest model, intubated and ventilated mice undergo a lateral blunt thoracotomy via the 4th intercostal space. Following identification of the left anterior descending a ligature is passed underneath the vessel and both suture ends are threaded through an occluder. Then, both suture ends are passed through the chest wall, knotted to form a loop and left in the subcutaneous tissue. After chest closure and recovery for 5 days, mice are anesthetized again, chest skin is reopened and hanging weights are hooked up to the loop under ECG control.
At the end of the ischemia/reperfusion protocol, hearts can be stained with TTC for infarct size assessment or undergo perfusion fixation to allow morphometric studies in addition to histology and immunohistochemistry.

Surgical trauma induces an inflammatory response. Cytokines and endogenous ligands are known to modulate myocardial infarct size following ischemia and reperfusion. We present a modified closed-chest model of murine ischemia and reperfusion using hanging weights to minimize effects of thoracotomy.

Um modelo fechado de tórax murino de isquemia do miocárdio e reperfusão

Surgical trauma by thoracotomy in open-chest models of coronary ligation induces an immune response which modifies different mechanisms involved in ...

Improvement of a Closed Chest Porcine Myocardial Infarction Model by Standardization of Tissue and Blood Sampling Procedures

Myocardial ischemia reperfusion (I/R) injury contributes to almost half of the necrotic area after myocardial infarction. To date there is no approved drug to prevent or reduce myocardial I/R injury. The study and understanding of the pathophysiological mechanisms of myocardial I/R injury is essential to develop successful treatments. Large animal experiments are an important step in translational methods. The porcine model of acute myocardial infarction has been established and described by ourselves and others. We aimed to further improve the value of the model by focusing in detail on the sampling techniques for use in future experiments. Furthermore, we emphasize small but important steps that can affect the quality of the final results. To mimic the clinical situation of myocardial I/R injury, a percutaneous coronary intervention (PCI) catheter was inserted into the left anterior descending coronary artery (LAD) of an anesthetized pig. &#176;&#176;&#176;This model mimics acute myocardial infarction and PCI treatment in humans with the possibility of accurately determining the area at risk as well as the necrotic- and viable ischemic tissue. Here the model was used to investigate the effect of a bicyclic peptide inhibitor of FXIIa. The model can also be modified to allow longer reperfusion times to study later effects of myocardial infarction.

Here we demonstrate a protocol to standardize sampling procedures of an established porcine model of acute myocardial infarction in order to increase its translational value in the understanding of the pathophysiology of myocardial ischemia/reperfusion injury and to test novel drug candidates.

Aprimoramento do modelo de suínos do miocárdio peito fechado pela padronização do tecido e os procedimentos de recolha de amostras de sangue

Myocardial ischemia reperfusion (I/R) injury contributes to almost half of the necrotic area after myocardial infarction. To date there is no approved ...

A Closed-chest Model to Induce Transverse Aortic Constriction in Mice

Research on cardiac hypertrophy and heart failure is frequently based on pressure overload mouse models induced by TAC. The standard procedure is to perform a partial thoracotomy to visualize the transverse aortic arch. However, the surgical trauma caused by the thoracotomy in open-chest models changes the respiratory physiology as the ribs are dissected and left unattached after chest closure. To prevent this, we established a minimally invasive, closed chest approach via lateral thoracotomy. Herein we approach the aortic arch via the 2nd intercostal space without entering the chest cavities, leaving the mouse with a less traumatic injury to recover from. We perform this operation using standard laboratory settings for open chest TAC procedures with equal survival rates. Apart from maintaining physiological breathing patterns due to the closed chest approach, the mice seem to benefit by showing rapid recovery, as the less invasive technique appears to facilitate a fast healing process and to reduce immune response after trauma.

Here, we present a protocol of Transverse Aortic constriction (TAC) via a lateral thoracotomy. This technique is a minimally invasive, closed chest surgical procedure aiming to simulate pressure overload and heart failure in mice utilizing standard TAC laboratory settings.

Um modelo de peito fechado para induzir a constrição da aorta transversa em ratos

Research on cardiac hypertrophy and heart failure is frequently based on pressure overload mouse models induced by TAC. The standard procedure is to ...

The Perinatal Asphyxiated Lamb Model: A Model for Newborn Resuscitation

Birth asphyxia accounts for nearly one million deaths worldwide each year, and is one of the primary causes of early neonatal morbidity and mortality. Many aspects of the current neonatal resuscitation guidelines remain controversial given the difficulties in conducting randomized clinical trials owing to the infrequent and often unpredictable need for extensive resuscitation. Most studies on neonatal resuscitation stem from manikin models that fail to truly reflect physiologic changes or piglet models that have cleared their lung fluid and that have completed the transition from fetal to neonatal circulation. The present protocol provides a detailed step-by-step description on how to create a perinatal asphyxiated fetal lamb model. The proposed model has a transitioning circulation and fluid-filled lungs, which mimics human newborns following delivery, and is, therefore, an excellent animal model to study newborn physiology. An important limitation to lamb experiments is the higher associated cost.

Invasive instrumentation of the fetal lamb provides accurate physiologic measurements of the transitioning circulation in a model that closely mimics the newly born infant.

A Perinatal asfixiado cordeiro modelo: Um modelo para a reanimação neonatal

Birth asphyxia accounts for nearly one million deaths worldwide each year, and is one of the primary causes of early neonatal morbidity and mortality. ...

Ultrasonographic Assessment During Cardiopulmonary Resuscitation

The US-CAB (Ultrasound, Circulation/Airway/Breathing) protocol integrates several sonographic techniques into a structured assessment of the circulation, airway, and breathing status of a patient during cardiopulmonary resuscitation (CPR) in an advanced life support-compliant manner. US-C provides a subxiphoid view of the heart, to look for potentially reversible causes of disease, such as pericardial effusion, pulmonary embolism, hypovolemia, and acute coronary thrombosis. Sonographic cardiac activity during CPR not only helps differentiate pseudo-pulseless electrical activity (PEA) from true PEA but also represents a higher chance of the return of spontaneous circulation (ROSC) and survival. Evaluation of the inferior vena cava (IVC) shows the fluid status of the patient and indicates the best methods to use for fluid resuscitation. If aortic dissection is suspected, a subxiphoid view of the aorta is suggested for identifying an intimal flap. Once intubation is done, tracheal ultrasound (US-A) at the suprasternal notch helps differentiate endotracheal intubation (one air-mucosal interface with one comet-tail) from esophageal intubation (double tract sign). Immediately following US-A, bilateral lung US (US-B) should be done to confirm proper bilateral ventilation using the lung sliding sign. In addition, US-C can be serially followed to see the dynamic changes in the cardiac chambers and IVC, or any cardiac contraction suggestive of ROSC. US-B can also detect coexisting lung or pleural pathologies without interfering with the performance of CPR. The main concern when implementing this method is maintaining high-quality CPR without delays in chest compressions when performing US-CAB. Rigorous training and continued practice are key to minimize any interruptions during resuscitation.

Here, we present a US-CAB (Ultrasound, Circulation/Airway/Breathing) protocol for use during cardiopulmonary resuscitation (CPR). US-C evaluates the subxiphoid view of the heart and inferior vena cava. After intubation, tracheal US (US-A) and lung US (US-B) help confirm endotracheal intubation and proper ventilation.

Avaliação ultrasonográfica durante a ressuscitação cardiopulmonar

The US-CAB (Ultrasound, Circulation/Airway/Breathing) protocol integrates several sonographic techniques into a structured assessment of the circulation, ...

Standardized Model of Ventricular Fibrillation and Advanced Cardiac Life Support in Swine

Cardiopulmonary resuscitation after cardiac arrest, independent of its origin, is a regularly encountered medical emergency in hospitals as well as preclinical settings. Prospective randomized trials in human subjects are difficult to design and ethically ambiguous, which results in a lack of evidence-based therapies. The model presented in this report represents one of the most common causes of cardiac arrests, ventricular fibrillation, in a standardized setting in a large animal model. This allows for reproducible observations and various therapeutic interventions under clinically accurate conditions, hence facilitating the generation of better evidence and eventually the potential for improved medical treatment.

Cardiopulmonary resuscitation and defibrillation are the only effective therapeutic options during cardiac arrest caused by ventricular fibrillation. This model presents a standardized regimen to induce, assess, and treat this physiological state in a porcine model, thus providing a clinical approach with various opportunities for data collection and analysis.

Modelo padronizado de Fibrilação Ventricular e Suporte avançado de vida cardíaca em suínos

Cardiopulmonary resuscitation after cardiac arrest, independent of its origin, is a regularly encountered medical emergency in hospitals as well as ...

Biventricular Assessment of Cardiac Function and Pressure-Volume Loops by Closed-Chest Catheterization in Mice

Assessment of cardiac function is essential to conduct cardiovascular and pulmonary-vascular preclinical research. Pressure-volume loops (PV loops) generated by recording both pressure and volume during cardiac catheterization are vital when assessing both systolic and diastolic cardiac function. Left and right heart function are closely related, reflected in ventricular interdependence. Thus, recording biventricular function in the same animal is important to get a complete assessment of cardiac function. In this protocol, a closed chest approach to cardiac catheterization consistent with the way catheterization is performed in patients is adopted in mice. While challenging, the closed chest strategy is a more physiological approach, because opening the chest results in major changes in preload and afterload that create artifacts, most notably a fall in systemic blood pressure. While high-resolution echocardiography is used to assess rodents, cardiac catheterization is invaluable, particularly when assessing diastolic pressures in both ventricles.
Described here is a procedure to perform invasive, closed chest, sequential left and right ventricular pressure-volume (PV) loops in the same animal. PV loops are acquired using&#160;admittance technology with a mouse pressure-volume catheter and pressure-volume system acquisition. The procedure is described, beginning with the neck dissection, which is required to access the right jugular vein and the right carotid artery, to the insertion and positioning of the catheter, and finally the data acquisition. Then, the criteria required to ensure the acquisition of high-quality PV loops are discussed. Finally, the analysis of the left and right ventricular PV loops and the different hemodynamic parameters available to quantify systolic and diastolic ventricular function are briefly described.

Presented here is a protocol to assess biventricular heart function in mice by generating pressure-volume (PV) loops from the right and left ventricle in the same animal using closed chest catheterization. The focus is on the technical aspect of surgery and data acquisition.

Avaliação Biventricular da Função Cardíaca e Alças Pressão-Volume por Cateterismo Fechado de Tórax em Camundongos

Assessment of cardiac function is essential to conduct cardiovascular and pulmonary-vascular preclinical research. Pressure-volume loops (PV loops) ...

Post-Myocardial Infarction Heart Failure in Closed-chest Coronary Occlusion/Reperfusion Model in G&#246;ttingen Minipigs and Landrace Pigs

The development of heart failure is the most powerful predictor of long-term mortality in patients surviving acute myocardial infarction (MI). There is an unmet clinical need for prevention and therapy of post-myocardial infarction heart failure (post-MI HF). Clinically relevant pig models of post-MI HF are prerequisites for final proof-of-concept studies before entering into clinical trials in drug and medical device development.
Here we aimed to characterize a closed-chest porcine model of post-MI HF in adult G&#246;ttingen minipigs with long-term follow-up including serial cardiac magnetic resonance imaging (CMRI) and to compare it with the commonly used Landrace pig model.
MI was induced by intraluminal balloon occlusion of the left anterior descending coronary artery for 120 min in G&#246;ttingen minipigs and for 90 min in Landrace pigs, followed by reperfusion. CMRI was performed to assess cardiac morphology and function at baseline in both breeds and at 3 and 6 months in G&#246;ttingen minipigs and at 2 months in Landrace pigs, respectively.
Scar sizes were comparable in the two breeds, but MI resulted in a significant decrease of left ventricular ejection fraction (LVEF) only in G&#246;ttingen minipigs, while Landrace pigs did not show a reduction of LVEF. Right ventricular (RV) ejection fraction increased in both breeds despite the negligible RV scar sizes. In contrast to the significant increase of left ventricular end-diastolic (LVED) mass in Landrace pigs at 2 months, G&#246;ttingen minipigs showed a slight increase in LVED mass only at 6 months.
In summary, this is the first characterization of post-MI HF in G&#246;ttingen minipigs in comparison to Landrace pigs, showing that the G&#246;ttingen minipig model reflects post-MI HF parameters comparable to the human pathology. We conclude that the G&#246;ttingen minipig model is superior to the Landrace pig model to study the development of post-MI HF.

Post-Myocardial Infarction Heart Failure in Closed-chest Coronary Occlusion/Reperfusion Model in G&amp;#246;ttingen Minipigs and Landrace Pigs

The overall goal of the current study is to present the techniques of induction of myocardial infarction (MI) and post-myocardial infarction heart failure (post-MI HF) in closed-chest, adult G&#246;ttingen minipigs and the characterization of post-MI HF model in G&#246;ttingen minipigs as compared to Landrace pigs.

Insuficiência cardíaca pós-miocárdio em oclusão coronariana de peito fechado/modelo de reperfusão em Miniporcos de Göttingen e Poros landrace

The development of heart failure is the most powerful predictor of long-term mortality in patients surviving acute myocardial infarction (MI). There is an ...

Closed Chest Biventricular Pressure-Volume Loop Recordings with Admittance Catheters in a Porcine Model

Pressure-volume (PV) loop recording enables the state-of-the-art investigation of load-independent variables of ventricular performance. Uni-ventricular evaluation is often performed in preclinical research. However, the right and left ventricles exert functional interdependence due to their parallel and serial connections, encouraging simultaneous evaluation of both ventricles. Furthermore, various pharmacological interventions may affect the ventricles and their preloads and afterloads differently. 
We describe our closed chest approach to admittance-based bi-ventricular PV loop recordings in a porcine model of acute right ventricular (RV) overload. We utilize minimally invasive techniques with all vascular accesses guided by ultrasound. PV catheters are positioned, under fluoroscopic guidance, to avoid thoracotomy in animals, as the closed chest approach maintains the relevant cardiopulmonary physiology. The admittance technology provides real-time PV loop recordings without the need for post-hoc processing. Furthermore, we explain some essential troubleshooting steps during critical timepoints of the presented procedure. 
The presented protocol is a reproducible and physiologically relevant approach to obtain a bi-ventricular cardiac PV loop recording in a large animal model. This can be applied to a large variety of cardiovascular animal research.

Here we present a closed chest approach to admittance-based bi-ventricular pressure-volume loop recordings in pigs with acute right ventricular dysfunction.

Gravações de loop de volume de pressão biventricular fechadas com cateteres de admissão em um modelo suíno

Pressure-volume (PV) loop recording enables the state-of-the-art investigation of load-independent variables of ventricular performance. Uni-ventricular ...