围产儿窒息羔羊模型: 新生儿复苏模型的建立
Summary
侵入性仪器的胎儿羔羊提供准确的生理测量的过渡循环的模型, 密切模仿新生儿。
Abstract
出生窒息每年在全世界造成近100万人死亡, 是新生儿早期发病率和死亡率的主要原因之一。目前新生儿复苏指南的许多方面仍然存在争议, 因为在进行随机临床试验方面存在困难, 因为需要进行广泛的复苏。大多数关于新生儿复苏的研究都来自于假人模型, 它们无法真正反映生理变化或仔猪模型, 清除了他们的肺液, 已经完成了从胎儿到新生儿循环的转变。本议定书提供了一个详细的分步说明如何创建围产期窒息胎儿羔羊模型。该模型有一个过渡循环和液体填充肺部, 模仿人类新生儿分娩后, 因此, 是一个良好的动物模型, 研究新生儿生理学。对羔羊实验的一个重要限制是较高的相关成本。
Introduction
围产期窒息发生在大约4每1000足月出生在美国和负责大约 25% 400万新生儿死亡全世界1,2。在胎儿的自然发育过程中, 必须在分娩和分娩期间进行几种适应, 以便在肺部作为气体交换器官的作用下, 从内到宫外孕环境进行无缝过渡。新生儿在出生时没有充分过渡的任何失败进一步损害了复苏的努力。当胎儿肺间隙不完整或延迟3、4和导致持续性高肺血管阻力的情况下,5会影响通气效果, 这仍然是最重要干预在窒息新生儿的复苏6。此外, 立即夹脐带和去除低阻胎盘可能导致心脏输出突变, 可能导致心肌功能障碍7,8。
由于不经常需要积极的复苏 (胸部按压和/或肾上腺素管理需要)1,9, 缺乏强有力的证据从大型随机临床试验, 以支持目前新生儿复苏计划 (NRP) 指南。在新生儿复苏的许多翻译研究研究使用产后动物模型 (特别是仔猪), 无法充分描述过渡胎儿循环和液体填充肺部的新生儿在分娩房间。鉴于与胎儿循环向新生儿循环过渡有关的独特挑战, 围产期窒息心脏骤停胎儿羔羊模型是研究新生儿复苏生理学的理想方法。
约瑟夫来源对胎儿羔羊的研究, 早在1930代初, 奠定了胎儿和新生儿生理学的基础10。在20世纪的后半部分 , 杰弗里？道斯对胎儿羔羊模型进行了创新细致的实验, 后来亚伯拉罕. 鲁道夫对胎儿的心血管和肺生理学知识作出了巨大贡献。11,12. 近年来, 对胎儿/新生儿羔羊模型的研究提供了更好的了解通气对血流动力学的影响13,14, 氧合效应对以及在脐带钳夹7、17中发生的循环变化。最后, 在过去的一年中, 新生羔羊作为一种新的模型来研究复苏18,19,20的血流动力学效应。对进行羔羊实验所涉及的内容, 以及对外科仪器和实验方法的详细描述, 将提出一个循序渐进的叙述。
Protocol
所有议定书均已由纽约州立大学布法罗 IACUC 机构动物保育和使用委员会批准。图 1显示了描述入侵和非侵入性监测的方法的说明。 1. 动物 使用时间日期, Q 发烧阴性, 怀孕母羊 (混合品种, 萨福克赛特-卡塔丁山品种) 与胎儿羔羊在127–143天怀孕。注: 绵羊足月妊娠期为145天, 127 只怀孕羔羊表现得像极端早产儿。 2. 手术前?…
Representative Results
根据胎儿羔羊的检测, 可以记录血流动力学变量 (图 3和图 4), 然后进行分析和解释 (图 5)。可以收集频繁的血液样本,图 6显示了其中一个实验的 pH 值和帕2数据。有时, 导管或流探头可能会出现故障或脱落, 因此数据不能收集和用于分析, 如图 7所示。 <…
Discussion
羔羊模型是可比的大小, 以人类新生儿和允许简易仪器测量侵入性血流动力学变量。胎儿/新生羔羊模型是一个宝贵的研究工具, 丰富的帮助了解过渡循环, 以及新生儿的肺和心血管生理学。多年来建立了几个实验性羔羊模型, 研究了持续性肺动脉高压导管中早产儿13、14、21、肺血流动力学的最佳通气策略。结扎模型…
Declarações
The authors have nothing to disclose.
Materials
| Babcock forceps | Miltex | 16-44 | |
| Blood pressure transducer | Becton Dickinson | P23XL-1 | Used with saline filled diaphragm domes |
| Blunt tipped scissors | Miltex | 98SCS50-56 | |
| Capnograph | Philips | 7900 | Used with Neonatal Flow Sensors |
| Cautery pencil | Valley Lab | 287879 | |
| Cautery unit | Valley Lab | SSE2K | |
| Curved Forceps | Everost | 711714 | |
| Data acquisition software | Biopac Systems Inc. | ACK100W | |
| EKG | Biopac Systems Inc. | ECG100C | |
| Endotracheal tube -cuffed | Rusch | 111780035 | |
| Flow modulator | Transonic Systems Inc. | T403 | |
| Flow-probe | Transonic Systems Inc. | MC4PSS-LS-WC100-CM4B-GA | |
| Gastric tube | Jorgensen Labs Inc. | J0106LE | To decompress and drain ewe stomach |
| Hair clipper | Andis Company | 65340 | # 40 Clipper Blade |
| Infant radiant warmer | GE healthcare | 7810 | |
| Intravenous catheters | Becton Dickinson | 381234 | |
| Iris surgical scissors | Patterson | 510585 | |
| Kelly Foreceps | Patterson | 510535 | |
| Mosquito Forceps | RICA Surgical Products INC | 1-74 | |
| Near-infrared spectroscopy | Nonin Medical Inc. | X-100M | Sensmart Equanox & PureSAT |
| RSO2 Sensor | Nonin Medical Inc. | 8004CB-NA | Neonatal |
| Scalpel handle and blade | Everost | 707203 | |
| Sutures -silk 2-0 | Covidien | SS-695 | Used for tying catheters to vessels |
| Sutures -vicryl 2-0 | Ethicon | J269H | Used for closing thoracotomy |
| T-piece resuscitator | Neo-Tee | MCM1050812 | |
| Umbilical ties | Jorgensen Labs Inc. | J0025UA | |
| Weitlander Retractor | Miltex | 11-625 |
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Citar este artigo
Vali, P., Gugino, S., Koenigsknecht, C., Helman, J., Chandrasekharan, P., Rawat, M., Lakshminrusimha, S., Nair, J. The Perinatal Asphyxiated Lamb Model: A Model for Newborn Resuscitation. J. Vis. Exp. (138), e57553, doi:10.3791/57553 (2018).