作者要感谢 Roberto、Rueda 和 Sergio Martínez 在动物技术支持方面的宝贵技术帮助。

该协议 （B09-17） 由 INER（Instituto Nacional de Enfermedades Respiratorias "Ismael Cosio Villegas"）的生物伦理委员会批准。本研究使用了 23 头临床健康的长白猪，无论性别，体重在 20-25 公斤之间。根据墨西哥官方标准17 和美国实验动物护理和使用指南18 的实验动物护理和使用技术规范处理动物。所有动物均来自 Instituto Nacional de Enfermedades Respiratorias Ismael Cosio Villegas，并被安置在相同的环境条件下的单独笼子中，随意提供水和食物。在所有动物中，在右颈静脉放置热稀释导管，在同一侧的颈动脉中放置动脉导管，收集血气，然后计算 CO。所用试剂和设备的详细信息列在 材料表中。
1. 实验准备
<ol><li>在三种 250 mL 0.9% 氯化钠溶液（生理盐水溶液，SS）中稀释 1000 IU 肝素。</li>
	<li>将压力传感器连接到生命体征监测仪。使用每个传感器测量热稀释导管相应端口的压力。</li>
	<li>通过无针静脉输注将肝素化溶液连接到换能器。确保它们已清除并准备好连接到导管。</li>
	<li>从包装中取出热稀释导管。将远端浸入 0.9% NaCl 中以检查球囊的完整性。</li>
	<li>检查远端和近端导管连接的通畅性。将导管放在手术器械台上直至使用。</li>
</ol>2. 动物准备
<ol><li>在动物准备室中肌肉注射 0.05 mg/kg 阿托品和 4 mg/kg tiletamine-zolazepam（遵循机构批准的方案）。</li>
	<li>让猪不受干扰，但受到监视，直到它们躺下并保持这个姿势，没有兴奋或对伤害性刺激有反应的迹象。</li>
	<li>将镇静的动物置于俯卧位，并将导管插入左耳的边缘静脉。</li>
	<li>将动物转移到手术室进行手术。</li>
	<li>将动物置于背侧位置，施用 4 mg/kg 异丙酚 IV、300 μg/kg 维库溴铵和 0.1 mg/kg 芬太尼 IV。</li>
	<li>在实验室工作人员的帮助下降低猪的下颌骨，以保持嘴巴张开和舌头伸出。</li>
	<li>将 10% 利多卡因喷洒在声带上，用环形镊子夹住纱布清除积聚的唾液，并将会厌与喉口分开。</li>
	<li>用喉镜和 3 号直刀片确定气管入口，然后用球囊插入 7 Fr 气管插管。</li>
	<li>在验证球囊在气道内的位置后，给球囊充气并将管子固定在下颌骨上。</li>
	<li>将猪连接到麻醉机上，以维持 2.5%-3% 七氟烷的麻醉状态（图 1）。</li>
	<li>以 25 次呼吸/分钟的频率，潮气量为 6-8 mL/kg 体重，FiO2% 为 50%-70% 以维持 SaO2 大于 90%，触发 2，呼气末正压 （PEEP） 为 5 cmH2O，吸气比为 1:2 s，吸气流量为 15 L/min，最大为 30 L/min。</li>
</ol>3. 放置热稀释导管和测量心输出量
<ol><li>在全身麻醉下将动物保持在背侧位置，并用碘泊维酮对颈部区域进行消毒（图 2）。使用电烙笔做一个 10 cm 的旁正中切口，解剖皮下组织，通过钝性解剖露出右颈外静脉。</li>
	<li>放置两条 2-0 丝缝合线，一条在解剖血管的远端部分，另一条在解剖血管的近端部分（图3）。</li>
	<li>将导管从颈部部位体外插入心脏所在的胸部区域。使用导管上的标记测量插入深度以到达肺动脉 （PA）。结扎血管的远端部分，并在近端放置一个双环，以便在插入后固定导管。</li>
	<li>使用虹膜剪刀在血管的腹侧部分做一个 2 毫米的横向切口。用 Halsted 蚊式止血钳打开切口边缘，将 5Fr 热稀释导管插入右颈静脉（图 4、 图 5 和 图 6）。按照监视器上显示的曲线将导管对准肺动脉 （PA）。</li>
</ol>4. 动脉导管的放置
<ol><li>一旦静脉被解剖并放置参考缝合线，将胸骨头肌（相当于胸锁乳突肌）向外侧移位。</li>
	<li>解剖气管前（胸骨舌骨）肌肉组织，直到露出颈动脉。</li>
	<li>将颈动脉与颈静脉类似地插管，并将其连接到压力传感器以监测体循环动脉压。</li>
</ol>5. 评估
<ol><li>将热稀释导管放置在右颈静脉中，并将动脉导管放置在同一侧的颈动脉中后，采集样本进行血气分析。</li>
	<li>使用热稀释法、体表面积和 Fick 法获取血气值并评估心输出量 （CO）。 注:有关详细程序，请参阅之前发布的报告19-21。</li>
</ol>6. 统计分析
<ol><li>使用方差分析 （ANOVA） 分析证明正态分布的数据，并执行 Tukey 事后检验。将值表示为平均值±标准误差。将 p 值 <0.05 视为表示统计显著性。</li>
</ol>7. 热稀释法测量
<ol><li>在不到 4 秒的时间内将 5 mL 冷 SS 在 4 °C 下推注到热稀释导管的近端管腔中。</li>
	<li>观察监视器屏幕上的热稀释曲线（温度/时间）。曲线应显示快速上升，然后平稳逐渐下降到基线，数值以小数点后一位或两位显示。</li>
	<li>用另外两次冷 SS 推注重复推注过程，直到曲线有效、相似且在平均值的 10% 以内。</li>
	<li>在确认曲线的有效性和相似性后，计算三个值的平均值并将其记录为最终的 CO 值，以升/分钟为单位。使用基于 Stewart-Hamilton 方程21 的计算从热稀释曲线中获得 CO 和其他指数。</li>
</ol>8. 确定体表面积 （BSA） 或心脏指数的调整后心输出量
<ol><li>要确定调整后的心输出量 （CI），请使用 DuBois-DuBois 公式19 计算体表面积 （BSA）: BSA = 0.007184 × （身高 （cm） 0.725） × （体重 （kg）0.425）。</li>
	<li>获得 BSA 后，使用公式20 计算 CI: CI = CO/BSA。 注:CO 在步骤 7 中确定。</li>
</ol>9. 通过 Fick 方法估计心输出量
<ol><li>要使用 Fick 方法计算心输出量 （CO），请确定耗氧量 （VO2） 以及从动脉 （SaO2） 和静脉 （SvO2） 血气获得的氧水平差异。使用公式2 计算 VO 21: VO2 = CO x （SaO2 - SvO2）。</li>
	<li>然后，使用公式21 确定心输出量: CO = VO2 / （[SaO2 - SvO2] × 10）。</li>
</ol>10. 估计每体重的心输出量
<ol><li>根据先前的报告 8,15 确定动物每体重的心输出量。 注:在 EVLP 方案中，各个小组报告称，猪每体重的估计心输出量 （CO） 为 100 mL/kg 8,15。</li>
</ol>11. 安乐死
<ol><li>一旦完成所有测量，通过颈静脉鞘（遵循机构批准的方案）用过量的戊巴比妥钠 （150 mg/kg/ IV） 对所有 动物实施安乐死。</li>
	<li>继续全身麻醉和心脏监测，直到心电图 （ECG） 轨迹显示无心脏电活动17,18。</li>
</ol>

猪颈静脉热稀释导管放置手术技术

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作者已声明不存在相互竞争的利益。

鉴于两个物种的大小、生理学和基因组序列的可比性，猪的 EVLP 可以直接转化为人类临床实践22。根据研究人员选择的 EVLP 方案，CO 的测量对于确定灌注肺部所需的流量至关重要。此外，根据可用的资源和知识，可以选择合适的方法。然而，没有研究将同时评估 CO 的方法与参考方法进行比较。因此，本研究旨在比较四种测量 CO 以估计 EVLP 期间肺流量的技术。我们纳入了实验性血...

在肺移植中心，离体肺灌注 （EVLP） 是一种工具，有助于增加捐献不符合移植标准标准的肺的可能性1。这是通过保存和改善脑死亡或心脏骤停供体的肺功能，以及通过评估移植前的肺功能来实现的 2,3,4。在 EVLP 中，体外循环泵允许通过膜气体交换器和白细胞捕获过滤器移植肺灌注5。
迄今为止，已经描述了几种 EVLP 方案（Toronto、Lund 和 Organ Care System）。这些根据所用灌注溶液的类型、灌注期间左心房是保持开放还是闭合，以及灌注流量（从供体估计心输出量 （CO） 的 40% 到 100%（取决于所使用的技术）不等）来区分 6,7,8。CO 是心脏每分钟泵送的血量9 ，是维持组织灌注的机制。因此，CO 监测可确保适当的组织氧合。CO 是心率和每搏输出量的乘积，以升 10,11,12 为单位。然而，这种维持组织灌注的方法还取决于其他因素，例如静脉回流、外周氧使用、全身血管阻力、呼吸、总血容量和体位12。
有几种用于测量和监测 CO 的设备，其中一些使用简单的物理原理，而另一些则使用数学模型。这些方法包括 Fick 原则、热稀释法（经肺或锂稀释）、动脉压波分析以估计每搏输出量 （SV） 以及多普勒或胸部生物反应等侵入性较小的方法。然而，由于相应监测技术的局限性，没有一种 CO 监测设备可以满足所有临床要求10,13。
通过经心热稀释法测量 CO 是一种简单且易于重现的猪方法。它包括在肺动脉中放置一根带有热敏电阻的导管，并注入一定量的液体，其温度低于血液的温度。热敏电阻检测温度随时间的变化，然后以曲线的形式绘制，曲线下的面积代表微小体积14。各种研究都表明，对于 EVLP 动物模型，可以通过重量 （100 mL/kg）15、热稀释法和 Fick 法10,13 来计算 CO。然而，在临床上，CO 是使用心脏指数 （CI） 计算的，该指数是根据供体的体表面积调整的 CO16。然而，没有研究在实验猪模型中比较这些方法。
本研究的目的是重现猪通过热稀释法测量的 CO，并将其精度和准确度与使用 BSA 调整的 CO、体重和 Fick 方法获得的精度和准确度进行比较，以确定 EVLP 期间的灌注流量。

<table><tbody><tr><td>Anesthesia machine</td><td>General Electric</td><td>Carescape 620</td><td></td></tr><tr><td>Atropine</td><td>Amixteria, Stern Pharma GmbH</td><td></td><td></td></tr><tr><td>Catheter Insyte Autoguard 20 GA</td><td>Becton Dickinson</td><td>381434</td><td></td></tr><tr><td>Electrocautery pencil</td><td>BBraun Aesculap</td><td>GN211</td><td></td></tr><tr><td>Endotracheal tube with a 7 Fr balloon</td><td>Rush</td><td>MG 027770 002</td><td></td></tr><tr><td>Fentanyl</td><td>Janssen-Cilag</td><td></td><td></td></tr><tr><td>Iodopovidone</td><td>Degasa</td><td>NDC6732635208</td><td></td></tr><tr><td>Laryngoscope</td><td>Riester</td><td></td><td></td></tr><tr><td>Lidocaine Spray</td><td>Pisa</td><td></td><td></td></tr><tr><td>Pressure transducers</td><td>Edwards Lifesciences</td><td>PX260</td><td></td></tr><tr><td>Propofol</td><td>Pisa</td><td></td><td></td></tr><tr><td>Sevofluorane</td><td>Pisa</td><td></td><td></td></tr><tr><td>Silk sutures 2-0</td><td>Covidien</td><td>GS833</td><td></td></tr><tr><td>Sodium pentobarbital</td><td>Pfizer</td><td></td><td></td></tr><tr><td>straight blade of laryngoscope #3</td><td>Miller; Riester</td><td></td><td></td></tr><tr><td>Swan-Ganz 5Fr thermodilution catheter</td><td>Arrow Thermodilution Ballon Catheter</td><td>Ref AI-07165</td><td></td></tr><tr><td>Tiletamine-zolazepam</td><td>Virbac</td><td></td><td></td></tr><tr><td>Vecuronium bromide</td><td>Pisa</td><td></td><td></td></tr></tbody></table>

determination of cardiac output in a porcine model for ex vivo pulmonary perfusion

由于猪与人类的生理相似性，猪被用作 离体 肺灌注 （EVLP） 的实验模型。EVLP 是一种通过体外循环泵灌注不适合移植的肺的技术，以改善其功能并提高其活力。现有的 EVLP 方案通过灌注溶液的类型和灌注流量进行区分，根据体表面积 （BSA），灌注流量从估计心输出量 （CO） 的 40%-100% 不等。用于测量 CO 的设备使用简单的物理原理和其他数学模型。动物模型中的热稀释法仍然是估计 CO 的参考标准品，因为它简单且易于复制。因此，本研究的目的是重现猪热稀释法对 CO 的测量，并将其精密度和准确度与 BSA、重量和 Fick 方法获得的精密度和准确度进行比较，以确定 EVLP 期间的灌注流量。在 23 头猪中，在右颈静脉放置热稀释导管，并在同一侧的颈动脉插管。获取血样进行气体测定，并通过热稀释法、调整体表面积、Fick 原理和体重估计 CO。BSA 获得的 CO 大于其他方法获得的 CO （p = 0.0001， ANOVA， Tukey）。我们得出的结论是，尽管本研究中用于估计 CO 的方法是可靠的，但它们之间存在显着差异;因此，每种方法都必须由研究者进行评估，以确定哪种方法符合方案的需要。

所有动物都在外科手术和研究时间内幸存下来。1 只动物 （4.3%） 由于导管插入过程中过度牵引而发生颈静脉撕裂。此外，干预血管均未出现出血。在研究动物中，平均需要 25-30 cm 的导管插入才能到达 PA。在 3 例 （13%） 中，导管对准猪的右上肢。在这些情况下，导管缩回插入部位，猪的上肢重新定位到头部，并手动阻塞颈静脉以将导管引向心脏。2 只动物 （8.6%） 在导管插入过程中出现心动过速...

作者聚焦: 通过热稀释法评估猪 EVLP 期间有效灌注流量的心输出量计算

该方案描述了用于通过猪颈静脉放置热稀释导管的手术技术，以估计心输出量并确保在 离体 肺灌注 （EVLP） 期间有足够的肺灌注。

猪离体肺灌注模型中心输出量的测定

Due to their physiological similarities to humans, pigs are used as experimental models for ex vivo lung perfusion (EVLP). EVLP is a technique that ...

determination-cardiac-output-porcine-model-for-ex-vivo-pulmonary

Research

JoVE Journal

Medicine

Determination of Cardiac Output in a Porcine Model for Ex Vivo Pulmonary Perfusion

427 次观看.  Instituto Nacional de Enfermedades Respiratorias Ismael Cosio Villegas. 进行这项研究是为了确保通过猪热病变法计算心输出量是否允许我们获得与其他技术获得的值相等的值，从而在实验动物模型中建立离体肺灌注或 EVLP 期间的足够灌注流量。挑战之一是开发新的低成本解决方案和技术来执行 EVLP，这将允许恢复在正常情况下可能被丢弃用于肺移植的肺，并允许延长肺保留。评估在不同灌注流量下长期保存至 EVLP 后肺?...

视频: 作者聚焦: 通过热稀释法评估猪 EVLP 期间有效灌注流量的心输出量计算

Procedure for Human Saphenous Veins Ex Vivo Perfusion and External Reinforcement

The mainstay of contemporary therapies for extensive occlusive arterial disease is venous bypass graft. However, its durability is threatened by intimal hyperplasia (IH) that eventually leads to vessel occlusion and graft failure. Mechanical forces, particularly low shear stress and high wall tension, are thought to initiate and to sustain these cellular and molecular changes, but their exact contribution remains to be unraveled. To selectively evaluate the role of pressure and shear stress on the biology of IH, an ex&#160;vivo perfusion system (EVPS) was created to perfuse segments of human saphenous veins under arterial regimen (high shear stress and high pressure). Further technical innovations allowed the simultaneous perfusion of two segments from the same vein, one reinforced with an external mesh. Veins were harvested using a no-touch technique and immediately transferred to the laboratory for assembly in the EVPS. One segment of the freshly isolated vein was not perfused (control, day 0). The two others segments were perfused for up to 7 days, one being completely sheltered with a 4 mm (diameter) external mesh. The pressure, flow velocity, and pulse rate were continuously monitored and adjusted to mimic the hemodynamic conditions prevailing in the femoral artery. Upon completion of the perfusion, veins were dismounted and used for histological and molecular analysis. Under ex&#160;vivo conditions, high pressure perfusion (arterial, mean = 100 mm Hg) is sufficient to generate IH and remodeling of human veins. These alterations are reduced in the presence of an external polyester mesh.

Procedure for Human Saphenous Veins Ex Vivo Perfusion and External Reinforcement

The mechanisms leading to the development of intimal hyperplasia (IH) and vein graft failure are still poorly understood. This study describes an ex&#160;vivo system to perfuse human veins under controlled flow and pressure. Furthermore the efficiency of external mesh reinforcement to limit the development of IH was evaluated.

步骤人类隐静脉<em&gt;前体内</em&gt;灌注和外部强化

The mainstay of contemporary therapies for extensive occlusive arterial disease is venous bypass graft. However, its durability is threatened by intimal ...

科研

医学

Method of Isolated Ex Vivo Lung Perfusion in a Rat Model: Lessons Learned from Developing a Rat EVLP Program

The number of acceptable donor lungs available for lung transplantation is severely limited due to poor quality. Ex-Vivo Lung Perfusion (EVLP) has allowed lung transplantation in humans to become more readily available by enabling the ability to assess organs and expand the donor pool. As this technology expands and improves, the ability to potentially evaluate and improve the quality of substandard lungs prior to transplant is a critical need. In order to more rigorously evaluate these approaches, a reproducible animal model needs to be established that would allow for testing of improved techniques and management of the donated lungs as well as to the lung-transplant recipient. In addition, an EVLP animal model of associated pathologies, e.g., ventilation induced lung injury (VILI), would provide a novel method to evaluate treatments for these pathologies. Here, we describe the development of a rat EVLP lung program and refinements to this method that allow for a reproducible model for future expansion. We also describe the application of this EVLP system to model VILI in rat lungs. The goal is to provide the research community with key information and &#8220;pearls of wisdom&#8221;/techniques that arose from trial and error and are critical to establishing an EVLP system that is robust and reproducible.

Method of Isolated Ex Vivo Lung Perfusion in a Rat Model: Lessons Learned from Developing a Rat EVLP Program

Ex-Vivo Lung Perfusion (EVLP) has allowed lung transplantation in humans to become more readily available by enabling the ability to assess organs and expand the donor pool. Here, we describe the development of a rat EVLP program and refinements that allow for a reproducible model for future expansion.

的隔离方法<em&gt;离体</em&gt;肺灌注的大鼠模型:教训制定鼠EVLP课程中学

The number of acceptable donor lungs available for lung transplantation is severely limited due to poor quality. Ex-Vivo Lung Perfusion (EVLP) has allowed ...

Primary Outcome Assessment in a Pig Model of Acute Myocardial Infarction

Mortality after acute myocardial infarction remains substantial and is associated with significant morbidity, like heart failure. Novel therapeutics are therefore required to confine cardiac damage, promote survival and reduce the disease burden of heart failure. Large animal experiments are an essential part in the translational process from experimental to clinical therapies. To optimize clinical translation, robust and representative outcome measures are mandatory. The present manuscript aims to address this need by describing the assessment of three clinically relevant outcome modalities in a pig acute myocardial infarction (AMI) model: infarct size in relation to area at risk (IS/AAR) staining, 3-dimensional transesophageal echocardiography (TEE) and admittance-based pressure-volume (PV) loops. Infarct size is the main determinant driving the transition from AMI to heart failure and can be quantified by IS/AAR staining. Echocardiography is a reliable and robust tool in the assessment of global and regional cardiac function in clinical cardiology. Here, a method for three-dimensional transesophageal echocardiography (3D-TEE) in pigs is provided. Extensive insight into cardiac performance can be obtained by admittance-based pressure-volume (PV) loops, including intrinsic parameters of myocardial function that are pre- and afterload independent. Combined with a clinically feasible experimental study protocol, these outcome measures provide researchers with essential information to determine whether novel therapeutic strategies could yield promising targets for future testing in clinical studies.

Reliable and accurate outcome assessment is the key for translation of preclinical therapies into clinical treatment. The current paper describes how to assess three clinically relevant primary outcome parameters of cardiac performance and damage in a pig acute myocardial infarction model.

急性心肌梗死的猪模型主要成果评估

Mortality after acute myocardial infarction remains substantial and is associated with significant morbidity, like heart failure. Novel therapeutics are ...

A Pre-Clinical Porcine Model of Orthotopic Heart Transplantation

Fifty-years following the first successful report, cardiac transplantation remains the gold-standard treatment for eligible patients with advanced heart failure. Multiple small-animal models of heart transplantation have been used to study the acute and long-term effects of novel therapies. However, few are tested and demonstrated success in clinical trials. It is of critical importance to evaluate new therapies in a clinically relevant large-animal model for efficient and reliable translation of basic studies&#39;&#160;findings. Here, we describe a pre-clinical large-animal (porcine) model of orthotopic heart transplantation that has been firmly established and previously used to investigate novel cardioprotective strategies. This procedure focuses on acute ischemia-reperfusion injury and is a reliable method to investigate novel interventions which have been tested and validated in smaller experimental models, such as the murine model. We demonstrate its usefulness in assessing cardiac performance during the early post-transplantation period and other potential possibilities enabled by the model.

Here, we describe a pre-clinical large-animal (porcine) model of orthotopic heart transplantation that has been firmly established and utilized to investigate novel cardioprotective strategies.

正交心脏移植的临床前猪模型

Fifty-years following the first successful report, cardiac transplantation remains the gold-standard treatment for eligible patients with advanced heart ...

Optocardiography and Electrophysiology Studies of Ex Vivo Langendorff-perfused Hearts

Small animal models are most commonly used in cardiovascular research due to the availability of genetically modified species and lower cost compared to larger animals. Yet, larger mammals are better suited for translational research questions related to normal cardiac physiology, pathophysiology, and preclinical testing of therapeutic agents. To overcome the technical barriers associated with employing a larger animal model in cardiac research, we describe an approach to measure physiological parameters in an isolated, Langendorff-perfused piglet heart. This approach combines two powerful experimental tools to evaluate the state of the heart: electrophysiology (EP) study and simultaneous optical mapping of transmembrane voltage and intracellular calcium using parameter sensitive dyes (RH237, Rhod2-AM). The described methodologies are well suited for translational studies investigating the cardiac conduction system, alterations in action potential morphology, calcium handling, excitation-contraction coupling and the incidence of cardiac alternans or arrhythmias.

The objective of this study was to establish a method for investigating cardiac dynamics using a translational animal model. The described experimental approach incorporates dual-emission optocardiography in conjunction with an electrophysiological study to assess electrical activity in an isolated, intact porcine heart model.

前维沃·兰根多夫注入心脏的心电生理学研究

Small animal models are most commonly used in cardiovascular research due to the availability of genetically modified species and lower cost compared to ...

Measuring Cardiac Output in a Swine Model

Swine are frequently used in medical research given their similar cardiac physiology to that of humans. Measuring cardiac parameters such as stroke volume and cardiac output are essential in this type of research. Contrast ventriculography, thermodilution, and pressure-volume loop (PV-loop) catheters can be used to accurately obtain cardiac performance data depending on which resources and expertise are available. For this study,five Yorkshire swine were anesthetized and intubated. Central venous and arterial access was obtained to place the necessary measurement instruments.A temperature probe was placed in the aortic root. A cold saline bolus was delivered to the right atrium and temperature deflection curve was recorded. Integration of the area under the curve allowed for the calculation of the current cardiac output.A pigtail catheter was percutaneously placed in the left ventricle and 30 mL of iodinated contrast was power injected over 2 seconds. Digital subtraction angiography images were uploaded to volumetric analysis software to calculate the stroke volume and cardiac output. A pressure volume-loop catheter was placed into the left ventricle (LV) and provided continuous pressure and volume data of the LV, which allowed the calculation of both stroke volume and cardiac output.All three methods demonstrated good correlation with each other. The PV-loop catheter and thermodilution exhibited the best correlation with a 3% error and a Pearson coefficient of 0.99, with 95% CI=0.97 to 1.1, (p=0.002). The PV-loop catheter against ventriculography also showed good correlation with a 6% error and a Pearson coefficient of 0.95, 95% CI=0.96 to 1.1 (p=0.01). Finally, thermodilution against ventriculography had a 2% error with r=0.95, 95% CI=0.93 to 1.11, (p=0.01). In conclusion, we state that the PV-loop catheter, contrast ventriculography, and thermodilution each offer certain advantages depending on the researcher's requirements. Each method is reliable and accurate for measuring various cardiac parameters in swine such as the stroke volume and cardiac output.

<meta charset="utf8"></head><body>在猪模型中测量心输出量

Thermodilution, pressure-volume loop catheters, and contrast ventriculography are reliable and accurate methods for determining cardiac physiology such as stroke volume and cardiac output in a laboratory setting in swine.

在猪模型中测量心输出量

Swine are frequently used in medical research given their similar cardiac physiology to that of humans. Measuring cardiac parameters such as stroke volume ...

Large-Animal Model of Donation after Circulatory Death and Normothermic Regional Perfusion for Cardiac Assessment

The increase in demand for cardiac transplantation throughout the years has fueled interest in donation after circulatory death (DCD) to expand the organ donor pool. However, the DCD process is associated with the risk of cardiac tissue injury due to the inevitable period of warm ischemia. Normothermic regional perfusion (NRP) allows for an in situ organ assessment, allowing the procurement of hearts determined to be viable. Here, we describe a clinically relevant large-animal model of DCD followed by NRP. Circulatory death is established in anesthetized pigs by stopping mechanical ventilation. After a preset warm ischemia period, an extracorporeal membrane oxygenator (ECMO) is used for a NRP period lasting at least 30 min. During this reperfusion period, the model allows the collection of various myocardial biopsies and blood samples for initial cardiac evaluation. Once NRP is weaned, biochemical, hemodynamic, and echocardiographic assessments of cardiac function and metabolism can be performed before organ procurement. This protocol closely simulates the clinical scenario previously described for DCD and NRP in heart transplantation and has the potential to facilitate studies aimed at decreasing ischemia-reperfusion injury and enhance cardiac functional preservation and recovery.

The protocol describes a large-animal (porcine) model of donation after circulatory death, followed by thoracoabdominal normothermic regional perfusion that closely simulates the clinical scenario in heart transplantation, and has the potential to facilitate therapeutic studies and strategies.

用于心脏评估的循环死亡后捐献和正常区域灌注的大型动物模型

The increase in demand for cardiac transplantation throughout the years has fueled interest in donation after circulatory death (DCD) to expand the organ ...

<meta charset="utf8"></head><body>研究猪模型中对急性容量超负荷的生理反应

Adult and Pediatric Porcine Model of Acute Volume Overload

This protocol describes an acute volume overload porcine model for adult Yorkshire pigs and piglets. Both swine ages undergo general anesthesia, endotracheal intubation, and mechanical ventilation. A central venous catheter and an arterial catheter are placed via surgical cutdown in the external jugular vein and carotid artery, respectively. A pulmonary artery catheter is placed through an introducer sheath of the central venous catheter. PlasmaLyte crystalloid solution is then administered at a rate of 100 mL/min in adult pigs and at 20 mL/kg boluses over 10 min in piglets. Hypervolemia is achieved either at 15% decrease in cardiac output or at 5 L in adult pigs and at 500 mL in piglets. Hemodynamic data, such as heart rate, respiratory rate, end-tidal carbon dioxide, fraction of oxygen-saturated hemoglobin, arterial blood pressure, central venous pressure, pulmonary artery pressure, pulmonary capillary wedge pressure, partial arterial oxygen pressure, lactate, pH, base excess, and pulmonary artery fraction of oxygen-saturated hemoglobin, are monitored during experimentation. Preliminary data observed with this model has demonstrated statistically significant changes and strong linear regressions between central hemodynamic parameters and acute volume overload in adult pigs. Only pulmonary capillary wedge pressure demonstrated both a linear regression and a statistical significance to acute volume overload in piglets. These models can aid scientists in the discovery of age-appropriate therapeutic and monitoring strategies to understand and prevent acute volume overload.

<meta charset="utf8"></head><body>作者聚焦:探索猪模型中的静脉波形以解决医学中的容量超负荷

The protocol here shows how continuous administration of crystalloids into the central veins of a euvolemic pig/piglet allows for the appropriate investigation of the physiological effects of acute volume overload.

猪离体肺灌注模型中心输出量的测定

副本

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步骤人类隐静脉

的隔离方法

急性心肌梗死的猪模型主要成果评估

正交心脏移植的临床前猪模型

前维沃·兰根多夫注入心脏的心电生理学研究

在猪模型中测量心输出量

在猪模型中测量心输出量

用于心脏评估的循环死亡后捐献和正常区域灌注的大型动物模型

成人和儿童猪急性容量超负荷模型

成人和儿童猪急性容量超负荷模型