作者要感谢GreD，克莱蒙奥弗涅大学和国际Chirurgie内窥镜中心（均位于法国克莱蒙费朗）的工作人员。

该研究方案由法国 国家教育部 动物伦理委员会批准，批准号为01505.03，然后于 preclinicaltrials.eu（临床前注册标识符 PCTE00000129）注册。所有程序均在法国克莱蒙费朗 克莱蒙奥弗涅大学国际儿童内窥镜中心根据动物研究：报告体内实验（ARRIVE）指南36进行。
1. 动物准备和麻醉
<ol><li>仔猪模式<ol>
<li>确保实验方案符合动物实验指南，包括3R原则（替换，减少和改进）和国家/国际法规。</li>
		<li>在开始协议之前，获得伦理委员会的批准，以便在相关机构中护理和使用实验动物。</li>
		<li>使用雄性白色Landrace仔猪（2-4个月大;体重10-15公斤）。</li>
		<li>使用肌内注射氮杂龙（如1.2.2中所述）在用药前将仔猪置于仰卧位。</li>
	</ol></li>
	<li>麻醉诱导<ol>
<li>限制动物过夜吃东西，同时允许自由取水。</li>
		<li>在耳后使用肌内注射氮杂松（2 mg.kg-1）对仔猪进行抗焦虑预用药。</li>
		<li>用手指按压仔猪耳基部的软组织，以识别内侧和外耳静脉。</li>
		<li>在仔猪的内侧或外耳静脉插入外周静脉注射22 G导管。随后以45°的浅角穿过皮肤，然后向前推进，直到血液通过导管出现。</li>
		<li>用静脉注射丙泊酚（3 mg.kg-1）和舒芬太尼（0.3μ g.kg-1）诱导全身麻醉37。通过对踏板反射缺乏反应来检查麻醉深度。</li>
	</ol></li>
	<li>气管插管38，39<ol>
<li>使用4号直米勒喉镜刀片准备喉镜。</li>
		<li>将喉镜进入咽腔，用喉镜刀片压低舌头，使会厌可见。</li>
		<li>在口管插管前观察仔猪的喉部开口。</li>
		<li>插入一个内径为 6 mm 的气管插管。</li>
		<li>给气管插管袖带充气，使气囊压力达到 2 O 左右 20–30cmH。</li>
		<li>用微孔手术胶带将气管插管固定在仔猪的鼻子上。</li>
		<li>连接到呼吸机，并按照第 3 节中描述的设置启动机械通气。</li>
	</ol></li>
	<li>镇静维持<ol>
<li>在酸性肺损伤前，通过连续静脉输注丙泊酚（5 mg.kg-1.h-1）来维持麻醉。当卤化剂开始时，丙泊酚的输注将停止。</li>
		<li>加入连续静脉输注瑞芬太尼（10–20 μ g.kg−1.h−1 = 0.15–0.33 μ g.kg−1.min−1）进行疼痛管理。</li>
		<li>加入连续静脉输注西沙曲库铵（0.2 mg.kg-1.h-1）进行神经肌肉阻滞。</li>
		<li>使用温暖的毯子将仔猪的体温保持在约38°C。</li>
		<li>使用外部监测仪连续监测心电图活动、外周血氧饱和度 （SpO2） 和动脉压。</li>
	</ol></li>
	<li>手术<ol>
<li>使用手术暴露右颈内静脉和Seldinger方法插入3腔导管（7法语，16cm）插入中心静脉通路。<ol>
<li>在颈部腹侧做一个皮肤中线切口，距气管2厘米。使用手术钳解剖组织。</li>
			<li>定位颈内静脉（约1-2厘米深，颈内动脉外侧），并使用针头（18 G，6.35厘米）进行颅尾方向的穿刺。</li>
			<li>用手将"J"导丝（直径0.81毫米，60厘米）插入针头。轻轻取出针头，并沿着"J"导丝快速将三条线的静脉导管插入颈内静脉。取出"J"导丝，同时保持静脉导管就位。</li>
			<li>通过静脉导管的每根管路抽吸血液，以除去不同管路中的空气，并用5mL盐水溶液（0.9%NaCl）冲洗三根管路。</li>
			<li>按照连续的Lembert图案，用3.0不可吸收的缝合线缝合皮肤，并在中心静脉导管的每个侧穿孔上用一针和三重结将导管固定在皮肤上。</li>
		</ol>
</li>
		<li>通过手术暴露右股动脉插入动脉线，并使用Seldinger方法插入热稀释导管（3-5法国，20厘米）。<ol>
<li>将仔猪的右前肢伸展。</li>
			<li>在仔猪的右腹股沟区域做一个皮肤切口。使用手术钳解剖皮下和肌肉组织。</li>
			<li>通过触诊股动脉脉搏（约3-4厘米深）定位右股动脉，并使用针头（19 G，54mm）进行尾颅方向的穿刺。</li>
			<li>将"J"导丝插入针头。轻轻取出针头，并沿着导丝快速将动脉插入股动脉。取下导丝，同时保持导管就位。</li>
			<li>从动脉导管中取出空气，用生理盐水冲洗以冲洗管路。</li>
			<li>按照连续的Lembert图案，用3.0不可吸收的缝合线缝合皮肤，并在动脉导管的每个侧穿孔上用一针和三重结将导管固定在皮肤上。</li>
			<li>将导管插入动脉管，以便使用脉搏轮廓心输出量监测装置检索连续血液样本和连续血流动力学监测（动脉压、心脏指数和血管外肺水，与体重挂钩）。</li>
		</ol>
</li>
	</ol></li>
</ol>2. 酸性急性肺损伤
注意：在此步骤中使用手套和眼镜，以避免酸与皮肤或眼睛接触的任何风险）
<ol><li>在 0.05 M 和 pH 1.4 下制备 100 mL HCl。</li>
	<li>使用胸骨最后一段的解剖标志，测量气管插管尖端与仔猪肉眼之间的距离。</li>
	<li>用Ch14吸盘上的黑色笔标记此距离。</li>
	<li>将吸入导管通过气管插管插入黑色标志。</li>
	<li>通过吸痰导管轻轻滴注4 mL.kg-1（ 体重）酸超过3分钟。</li>
	<li>取出吸管。</li>
</ol>3. 机械通气
<ol><li>在重症监护呼吸机上使用容量控制通气。</li>
	<li>使用6 mL.kg-1的潮气量，呼气末正压（PEEP）为5 cmH2O，吸入氧分数（FiO2）为40%。</li>
	<li>调整呼吸频率，将潮末二氧化碳维持在35至45毫米汞柱之间。 注：根据先前的研究37，40，41，当动脉氧张力（PaO2）与FiO2的比例从基线降低到25%时，肺损伤被认为是确定的，大约在气道HCl滴注后1小时。</li>
</ol>4. 卤化麻醉剂
注意：一旦达到酸性肺损伤，使用卤化麻醉剂（七氟醚或异氟醚）开始镇静。然后应中断使用丙泊酚的静脉镇静剂。
<ol><li>填充注射器（图1A）：将制造商提供的填充适配器连接到250 mL卤化剂瓶中，将60 mL注射器连接到填充适配器。将瓶子倒置，通过推拉柱塞来填充注射器。将瓶子直立并取出注射器。</li>
	<li>清道夫（图1B）<ol>
<li>放置木炭过滤器，用于去除卤代烃麻醉气体，靠近通风机。</li>
		<li>从木炭过滤器上取下保护盖。</li>
		<li>用柔性管将木炭过滤器连接到呼吸机的呼气阀。</li>
	</ol>
</li>
	<li>使用麻醉保存装置（用于吸入ICU镇静的装置）（图1C），如下所述。<ol>
<li>将离聚膜干燥器管路连接到麻醉保存装置的气体采样口。</li>
		<li>将气体采样管路的一侧连接到离聚膜干燥器管路。</li>
		<li>将气体采样管路的另一侧连接到气体分析仪。</li>
		<li>将麻醉保存装置插入呼吸回路的Y形片和气管插管之间。</li>
		<li>确保麻醉剂保存装置的黑色面朝上，并向下倾斜到仔猪。</li>
	</ol>
</li>
	<li>通过麻醉保存装置提供吸入镇静剂（图2）。<ol>
<li>将特定的注射器放入注射器泵中。</li>
		<li>将麻醉剂线连接到注射器。</li>
		<li>用1.5 mL卤化剂的推注剂开始剂生产线。</li>
		<li>调整以mL.h-1 为单位的初始泵速（异氟醚和七氟醚的初始注射器泵速设置分别为3和5 mL / h）以适应目标过期的七氟醚馏分（FEsevo）或过期的异氟醚馏分（FEiso）值，如气体分析仪上所示。</li>
		<li>确保气体分析仪显示 FEsevo %–FE等值 % 或等效的最小肺泡浓度值大于零。如有必要，额外追加0.3 mL卤化剂。</li>
		<li>根据分钟体积和目标浓度调整注射器泵速率以达到一定浓度，通常，2-7 mL.h-1和4-10 mL.h-1的速率与异氟醚42和七氟醚28，43的0.2%-0.7%和0.5%-1.4%的过期馏分相关。</li>
		<li>在实验过程中，继续施用FEsevo和FEiso靶标分别为0.8-1.1和0.5-0.8的卤化剂。</li>
	</ol>
</li>
</ol>5. 测量
<ol><li>监测<ol>
<li>收集由外部监护仪测量的不同参数：心率、血压和外周血氧饱和度。</li>
		<li>记录呼吸机测量的参数：潮气量、呼吸频率、设置 PEEP、自动 PEEP（通过在呼吸机上应用 5 s 的呼气保持操作）、呼吸系统的顺应性、气道阻力、吸气平台压力（通过在呼吸机上应用 2 秒的吸气保持操作）、吸气峰值压力和驱动压力。</li>
		<li>如果集成在呼吸机中，则使用氮气冲洗/冲洗方法计算肺功能残余容量。</li>
		<li>使用先前插入股动脉的热指示器测量肺的血管外水量、心脏指数和全身血管阻力。</li>
	</ol>
</li>
	<li>未稀释的肺水肿液采样以测量净AFC率。<ol>
<li>通过气管插管将柔软的14 Fr吸入导管插入支气管远端的楔形位置。</li>
		<li>通过施加轻柔的吸力将水肿液取样到吸力陷阱中。</li>
		<li>在冷藏离心机中以 240×g 在4°C下离心所有样品10分钟。</li>
		<li>收集上清液。 注意：未稀释的肺水肿液中的总蛋白浓度用比色法测量。由于水肿液从肺泡间隙的清除率远快于蛋白质去除率，因此净AFC率计算为百分比AFC = 100×[1 - （初始水肿蛋白/最终水肿总蛋白）]，此后报告为%/h37。未稀释的肺水肿液样本在基线和4小时后从动物中收集，如前所述34，44，45，46，47，48，49。</li>
	</ol>
</li>
	<li>迷你支气管肺泡灌洗采样。<ol>
<li>将软的14 Fr吸管插入气管管远端支气管的楔形位置。</li>
		<li>将50mL氯化钠溶液滴入吸入导管中。</li>
		<li>立即将流体取样到抽吸疏水阀中。</li>
		<li>收集迷你支气管肺泡灌洗液。 注意：使用比色法测量mini BAL中的总蛋白质浓度，例如，使用多重免疫测定法测量促炎细胞因子的水平，例如TNF-α，IL-6，IL-1β和IL-18。在酸性肺损伤后4小时收集样本。</li>
	</ol>
</li>
	<li>血气分析<ol>
<li>在基线处用 BD Luer-Lok 尖端的 3 mL BD 预设注射器通过动脉线收集动脉血气。使用床旁血气分析仪立即测量PaO2/FiO2、PaCO 2、pH值、血清乳酸和血清肌酐。</li>
		<li>在酸滴注后每小时重复此步骤4小时。</li>
	</ol>
</li>
	<li>肺部采样<ol>
<li>在实验结束时（酸性肺损伤后4小时）静脉注射戊巴比妥（150 mg.kg-1）牺牲仔猪。</li>
		<li>解剖并切除整个肺部。用酒精乙化福尔马林固定。</li>
		<li>潷入石蜡中，以10μm的厚度切片。</li>
		<li>用苏木精和曙红染色。 注意：可以使用标准化的组织学损伤评分50来评估肺损伤的组织学证据。</li>
	</ol>
</li>
</ol>

作者没有什么可透露的。

本文介绍了由小猪气管内滴注HCl诱导的ARDS的可重复实验模型，以研究使用麻醉保存装置输送的卤化挥发物（如七氟醚或异氟醚）的肺保护作用。
本研究的主要目标是开发一种ARDS的实验模型，其中挥发性药物可以通过麻醉剂保存装置（例如ICU患者中使用的装置）输送。虽然卤化剂的一些效应以前已经在动物模型中研究过，但我们模型的优势在于它是一种临床相关的转化模型，...

急性呼吸窘迫综合征（ARDS）是危重患者低氧血症性呼吸衰竭和死亡的常见原因1。其特征是弥漫性肺泡上皮和内皮损伤，导致通透性和肺水肿增加，肺泡液清除率改变（AFC）和呼吸窘迫恶化2。肺泡水肿的再吸收和ARDS的恢复需要上皮液通过肺泡的运输以保持完整，这表明改善AFC的治疗可能是有用的3，4。尽管肺保护性通气和静脉输液治疗的限制性策略已被证明有益于改善结局2，5，但它们仍然与高死亡率和发病率相关6。因此，迫切需要为该综合征开发有效的治疗方法，并更好地了解这些疗法可能起作用的确切机制。
异氟醚或七氟醚等卤化麻醉剂已被广泛用于手术室的全身麻醉。七氟醚与接受胸外科手术的患者肺部炎症减少以及术后肺部并发症（如ARDS7）的减少有关。在心脏手术后患者的荟萃分析中也发现了类似的结果8。卤化挥发物还具有支气管扩张作用9，10，也许还有一些保护几个器官的特性，如心脏8，11和肾脏12，13，14。最近，人们对在重症监护病房（ICU）中将吸入麻醉剂作为镇静剂的临床使用越来越感兴趣。动物和人类研究都支持在肝脏15，大脑16或心脏11长期缺血之前用卤化剂进行预处理的保护作用。与其他静脉注射药物相比，卤化药物在镇静危重患者方面还具有潜在的药代动力学和药效学优势，包括快速起效和由于组织中积累很少而快速抵消。与接受心脏手术的患者的静脉镇静相比，吸入卤素药物可减少插管时间17。一些研究支持卤化剂在ICU患者镇静中的安全性和有效性18，19，20。在ARDS的实验模型中，吸入七氟醚改善气体交换21，22，减少肺泡水肿21，22，并减轻肺部和全身炎症23。异氟醚还通过维持肺泡 - 毛细血管屏障的完整性来改善损伤后的肺修复，可能是通过调节关键的紧密连接蛋白24，25，26的表达。此外，与未用异氟醚27处理的巨噬细胞相比，用异氟醚培养和处理的小鼠巨噬细胞对嗜中性粒细胞具有更好的吞噬作用。
然而，迄今为止，解释挥发性麻醉剂的肺保护特性的确切生物学途径和机制仍然在很大程度上是未知的，需要进一步研究18。还需要进行其他研究，以调查七氟醚对肺损伤的确切影响，并验证实验证据是否可以转化为患者。我们团队的第一项随机对照试验发现，在ARDS患者中吸入七氟醚的给药与氧合作用改善和促炎细胞因子和肺上皮损伤标志物水平降低有关，如晚期糖基化终产物（sRAGE）的血浆和肺泡可溶性受体评估的那样28.由于sRAGE现在被认为是肺泡1型细胞损伤的标志物和肺泡炎症的关键介质，这些结果可能表明七氟醚对肺泡上皮损伤的一些有益作用21，29，30。
使用卤化剂进行吸入性 ICU 镇静长期以来一直需要在 ICU 中部署手术室麻醉呼吸机和气体蒸发器。从那时起，已经开发了适合与现代重症监护呼吸机一起使用的麻醉反射器，用于ICU31中的特定用途。这些装置具有经过改良的热和水分交换过滤器，插入呼吸回路的Y形件和气管插管之间。它们允许施用卤化剂，其中异氟醚和七氟醚是最常用的，它们由多孔聚丙烯蒸发器棒组成，通过特定的注射器泵输送的液体剂被释放到其中。卤化剂在过期期间被装置中所含的反射介质吸收，并在下一次吸气期间释放，允许约90%的过期卤化剂31，32再循环。最近，开发了该设备的微型版本，仪器死区为50 mL，使其更适合在ARDS患者的超保护通气期间使用，潮气量可低至200 mL31。这种小型化装置从未在ARDS的实验仔猪模型中进行过研究。
由于先前的研究支持卤化挥发物在ARDS期间肺泡炎症和损伤中的有希望的作用，因此我们设计了一个实验动物模型，以实现对卤化剂对肺损伤和修复作用机制的转化理解33，34，35。在这项研究中，我们开发了一种盐酸（HCl）诱导的猪的ARDS模型，其中可以使用麻醉剂保存装置（ICU型装置）的微型版本进行吸入镇静。这种ARDS的大型动物模型可用于进一步了解吸入卤化剂的潜在肺保护作用。

<table>
	<tbody>
		<tr>
			<td>Tracheal intubation</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Endotracheal tube 6-mm</td>
			<td>Covidien</td>
			<td>18860</td>
			<td></td>
		</tr>
		<tr>
			<td></td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Animal preparation</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Central venous catheter 3-lumens catheter (7 French - 16 cm)</td>
			<td>Arrow</td>
			<td>CV-12703</td>
			<td></td>
		</tr>
		<tr>
			<td>Pulse contour cardiac output monitor PiCCO catheter (3-5 French - 20 cm)</td>
			<td>Getinge Pulsion Medical System</td>
			<td>catheter</td>
			<td></td>
		</tr>
		<tr>
			<td>Warm blankets WarmTouch5300</td>
			<td>MedTronic</td>
			<td>5300</td>
			<td></td>
		</tr>
		<tr>
			<td></td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Monitoring</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>External monitor IntelliVue MP40</td>
			<td>Phillips</td>
			<td>MNT 142</td>
			<td></td>
		</tr>
		<tr>
			<td>Point-of-care blood gas analyzer Epoc&#174; Blood Analysis System</td>
			<td>Siemens</td>
			<td>20093</td>
			<td></td>
		</tr>
		<tr>
			<td>Pulse contour cardiac output monitor PiCCO Device PulsioFlex Monitor</td>
			<td>Getinge Pulsion Medical System</td>
			<td>PulsioFlex</td>
			<td></td>
		</tr>
		<tr>
			<td></td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Mechanical ventilation</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Ventilator Engstr&#246;m Carestation</td>
			<td>General Electrics</td>
			<td>Engstr&#246;m</td>
			<td></td>
		</tr>
		<tr>
			<td></td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Halogenated anesthetics</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Anaconda Syringe</td>
			<td>SedanaMedical</td>
			<td>26022</td>
			<td></td>
		</tr>
		<tr>
			<td>Anesthetic conserving device AnaConDa-S</td>
			<td>SedanaMedical</td>
			<td>26050</td>
			<td></td>
		</tr>
		<tr>
			<td>Charcoal filter FlurAbsorb</td>
			<td>SedanaMedical</td>
			<td>26096</td>
			<td></td>
		</tr>
		<tr>
			<td>Filling Adaptaters</td>
			<td>SedanaMedical</td>
			<td>26042</td>
			<td></td>
		</tr>
		<tr>
			<td>Ionomer membrane dryer line Nafion</td>
			<td>SedanaMedical</td>
			<td>26053</td>
			<td></td>
		</tr>
		<tr>
			<td></td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Products</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Propofol</td>
			<td>Mylan</td>
			<td>66617123</td>
			<td></td>
		</tr>
		<tr>
			<td>Isoflurane</td>
			<td>Virbac</td>
			<td>QN01AB06</td>
			<td></td>
		</tr>
		<tr>
			<td>Pentobarbital</td>
			<td>PanPharma</td>
			<td>68942457</td>
			<td></td>
		</tr>
		<tr>
			<td>Sevoflurane</td>
			<td>Abbvie</td>
			<td>N01AB08</td>
			<td></td>
		</tr>
		<tr>
			<td>Sufentanil</td>
			<td>Mylan</td>
			<td>62404996</td>
			<td></td>
		</tr>
	</tbody>
</table>

halogenated agent delivery in porcine model of acute respiratory distress syndrome via an intensive care unit type device

急性呼吸窘迫综合征（ARDS）是危重患者低氧血症性呼吸衰竭和死亡的常见原因，迫切需要找到有效的治疗方法。临床前研究表明，吸入卤化剂可能对ARDS的动物模型有益。使用现代重症监护病房（ICU）呼吸机管理卤化剂的新设备的开发大大简化了卤化剂向ICU患者的分配。由于先前的实验和临床研究表明卤化挥发物（如七氟醚或异氟醚）对肺泡上皮损伤和炎症（ARDS期间弥漫性肺泡损伤的两种病理生理学标志物）的潜在益处，因此我们设计了一个动物模型来了解卤化剂对肺损伤和修复的影响机制。在全身麻醉、气管插管和开始机械通气后，通过气管内滴注盐酸在仔猪中诱导ARDS。然后，使用ICU型装置用吸入的七氟醚或异氟醚镇静仔猪，并在4 h期间用肺保护性机械通气对动物进行通气。在研究期间，收集血液和肺泡样本以评估动脉氧合，肺泡毛细血管膜的通透性，肺泡液清除率和肺部炎症。在整个实验过程中还收集了机械通气参数。尽管该模型诱导动脉氧合显著降低，肺泡-毛细血管通透性改变，但其可重复性，其特征是起效快、随时间稳定性好且无致命并发症。
我们开发了一种酸吸入仔猪模型，该模型再现了临床ARDS的大部分生理，生物学和病理学特征，这将有助于我们进一步了解通过用于吸入ICU镇静的装置输送的卤化剂的潜在肺保护作用。

本实验将25头仔猪麻醉，分为两组：未治疗组（SHAM组）12头仔猪和酸损伤组（HCl组）13头仔猪。在实验结束之前，没有仔猪死亡。双向重复测量方差分析（RM-方差分析）表明，与没有ARDS的假动物相比，组相互作用（P<10−4）存在显着的时间，HCl诱导的ARDS对PaO2/ FiO2具有不利影响（图3）。在机械通气4小时后测量的总蛋白的未稀释肺水肿液水平中，观察?...

Watch this Scientific Journal Video about Halogenated Agent Delivery in Porcine Model of Acute Respiratory Distress Syndrome via an Intensive Care Unit Type Device at JoVE.com

Halogenated Agent Delivery in Porcine Model of Acute Respiratory Distress Syndrome via an Intensive Care Unit Type Device

我们描述了盐酸诱导的急性呼吸窘迫综合征（ARDS）的模型，该模型通过用于吸入重症监护镇静剂的装置接受卤化剂，异氟醚和七氟醚镇静的仔猪。该模型可用于研究卤化剂对肺损伤和修复的生物学机制。

重症监护病房型装置在猪模型急性呼吸窘迫综合征中的卤化剂递送

Acute respiratory distress syndrome (ARDS) is a common cause of hypoxemic respiratory failure and death in critically ill patients, and there is an urgent ...

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2.6K 次观看.  CHU Clermont-Ferrand. 我们描述了盐酸诱导的急性呼吸窘迫综合征（ARDS）的模型，该模型通过用于吸入重症监护镇静剂的装置接受卤化剂，异氟醚和七氟醚镇静的仔猪。该模型可用于研究卤化剂对肺损伤和修复的生物学机制。

视频: Halogenated Agent Delivery in Porcine Model of Acute Respiratory Distress Syndrome via an Intensive Care Unit Type Device

Lavage-induced Surfactant Depletion in Pigs As a Model of the Acute Respiratory Distress Syndrome (ARDS)

Various animal models of lung injury exist to study the complex pathomechanisms of human acute respiratory distress syndrome (ARDS) and evaluate future therapies. Severe lung injury with a reproducible deterioration of pulmonary gas exchange and hemodynamics can be induced in anesthetized pigs using repeated lung lavages with warmed 0.9% saline (50 ml/kg body weight). Including standard respiratory and hemodynamic monitoring with clinically applied devices in this model allows the evaluation of novel therapeutic strategies (drugs, modern ventilators, extracorporeal membrane oxygenators, ECMO), and bridges the gap between bench and bedside. Furthermore, induction of lung injury with lung lavages does not require the injection of pathogens/endotoxins that impact on measurements of pro- and anti-inflammatory cytokines. A disadvantage of the model is the high recruitability of atelectatic lung tissue. Standardization of the model helps to avoid pitfalls, to ensure comparability between experiments, and to reduce the number of animals needed.

Lavage-induced Surfactant Depletion in Pigs As a Model of the Acute Respiratory Distress Syndrome ARDS

Repeated pulmonary lavages in anesthetized pigs induce lung injury resembling major aspects of human acute respiratory distress syndrome (ARDS). For this purpose the lungs are repeatedly lavaged with 0.9% saline at 37 &#176;C. The goal of the protocol is a reproducible mitigation of gas exchange and hemodynamics for research in ARDS.

灌洗诱发的表面活性剂耗尽猪一样的急性呼吸窘迫综合征模型（ARDS）

Various animal models of lung injury exist to study the complex pathomechanisms of human acute respiratory distress syndrome (ARDS) and evaluate future ...

科研

医学

Oleic Acid-Injection in Pigs As a Model for Acute Respiratory Distress Syndrome

The acute respiratory distress syndrome is a relevant intensive care disease with an incidence ranging between 2.2% and 19% of intensive care unit patients. Despite treatment advances over the last decades, ARDS patients still suffer mortality rates between 35 and 40%. There is still a need for further research to improve the outcome of patients suffering from ARDS. One problem is that no single animal model can mimic the complex pathomechanism of the acute respiratory distress syndrome, but several models exist to study different parts of it. Oleic acid injection (OAI)-induced lung injury is a well-established model for studying ventilation strategies, lung mechanics and ventilation/perfusion distribution in animals. OAI leads to severely impaired gas exchange, deterioration of lung mechanics and disruption of the alveolo-capillary barrier. The disadvantage of this model is the controversial mechanistic relevance of this model and the necessity for central venous access, which is challenging especially in smaller animal models. In summary, OAI-induced lung injury leads to reproducible results in small and large animals and hence represents a well-suited model for studying ARDS. Nevertheless, further research is necessary to find a model that mimics all parts of ARDS and lacks the problems associated with the different models existing today.

In this article, we present a protocol to induce acute lung injury in pigs by central-venous injection of oleic acid. This is an established animal model for studying the acute respiratory distress syndrome (ARDS).

油酸注射液在猪急性呼吸窘迫综合征模型中的研究

The acute respiratory distress syndrome is a relevant intensive care disease with an incidence ranging between 2.2% and 19% of intensive care unit ...

A Protocol to Set Up Needle-Free Connector with Positive Displacement on Central Venous Catheter in Intensive Care Unit

Needle-free connectors were initially designed and promoted to avoid blood exposure for healthcare workers. Some recent data suggest that the latest generation of connectors (with positive displacement) may be of interest for reducing central venous line infections. We have been using needle-free connectors for several years in our intensive care unit and here we present a protocol for installing these connectors on central venous catheters. After insertion of the catheter and control of the permeability of the lines, the connectors must be purged with 0.9% NaCl before being connected. The connectors replace all disposable caps used on infusion stopcocks and manifolds. All the connectors are changed every 7 days as recommended by the manufacturer (except when there is macroscopic contamination, which requires an immediate change of the connector). Before each injection, the connector must be disinfected for at least 3 seconds with 70% isopropyl alcohol. The connectors must not be disconnected (unless changed), as the injection is done through the device. Setting up the connectors slightly increases the total time required to place the catheter and there is no formal evidence that these connectors reduce the incidence of infectious or thrombotic complications. However, these devices simplify the management of central venous lines and prevent the catheter circuit from &#34;opening&#34; once it has been sterilely installed.

We present a protocol to show the installation of a needle-free connector with positive displacement on a central venous catheter.

在重症监护病房的中央静脉导管上设置无针接头,带正位移

Needle-free connectors were initially designed and promoted to avoid blood exposure for healthcare workers. Some recent data suggest that the latest ...

Inducing Acute Lung Injury in Mice by Direct Intratracheal Lipopolysaccharide Instillation

Airway administration of lipopolysaccharide (LPS) is a common way to study pulmonary inflammation and acute lung injury (ALI) in small animal models. Various approaches have been described, such as the inhalation of aerosolized LPS as well as nasal or intratracheal instillation. The presented protocol describes a detailed step-by-step procedure to induce ALI in mice by direct intratracheal LPS instillation and perform FACS analysis of blood samples, bronchoalveolar lavage (BAL) fluid, and lung tissue. After intraperitoneal sedation, the trachea is exposed and LPS is administered via a 22 G venous catheter. A robust and reproducible inflammatory reaction with leukocyte invasion, upregulation of proinflammatory cytokines, and disruption of the alveolo-capillary barrier is induced within hours to days, depending on the LPS dosage used. Collection of blood samples, BAL fluid, and lung harvesting, as well as the processing for FACS analysis, are described in detail in the protocol. Although the use of the sterile LPS is not suitable to study pharmacologic interventions in infectious diseases, the described approach offers minimal invasiveness, simple handling, and good reproducibility to answer mechanistic immunological questions. Furthermore, dose titration as well as the use of alternative LPS preparations or mouse strains allow modulation of the clinical effects, which can exhibit different degrees of ALI severity or early vs. late onset of disease symptoms.

Presented here is a step-by-step procedure to induce acute lung injury in mice by direct intratracheal lipopolysaccharide instillation and to perform FACS analysis of blood samples, bronchoalveolar lavage fluid, and lung tissue. Minimal invasiveness, simple handling, good reproducibility, and titration of disease severity are advantages of this approach.

通过直接内切内脂多糖灌输诱导小鼠急性肺损伤

Airway administration of lipopolysaccharide (LPS) is a common way to study pulmonary inflammation and acute lung injury (ALI) in small animal models. ...

Assessment of Dependence in Activities of Daily Living Among Older Patients in an Acute Care Unit

During an acute medical problem, older people may lose functional independence. ADL scales are used to assess this loss of independence. The simplest and most convenient ADL scale is the Katz Index, which measures six ADL: bathing, dressing, toileting, transferring, continence, and feeding. A lower ADL score indicates greater loss of functional independence. The ADL score prior to the acute medical problem (baseline) is estimated by questioning the patient or the caregivers, and this score is then compared with that on hospital admission. The ADL score should be monitored from hospital admission until discharge to allow early detection of changes in functional independence. Identifying any loss of functional independence before and during hospitalization provides information to caregivers regarding the risk of short-term mortality risk and complications, and the prognosis after hospitalization.

During acute medical problems, older people may lose independence in activities of daily living (ADL). Assessment of baseline ADL and ADL on admission can guide personalized treatment plans aimed at preventing nosocomial dependence and ensuring better functional outcomes.

急性护理科老年患者日常生活活动依赖性评价

During an acute medical problem, older people may lose functional independence. ADL scales are used to assess this loss of independence. The simplest and ...

A Reproducible Intensive Care Unit-Oriented Endotoxin Model in Rats

Sepsis and septic shock remain the leading cause of death in intensive care units. Despite significant improvements in sepsis management, mortality still ranges between 20 and 30%. Novel treatment approaches in order to reduce sepsis-related multiorgan failure and death are urgently needed. Robust animal models allow for one or multiple treatment approaches as well as for testing their effect on physiological and molecular parameters. In this article, a simple animal model is presented.
First, general anesthesia is induced in animals either with the use of volatile or by intraperitoneal anesthesia. After placement of an intravenous catheter (tail vein), tracheostomy, and insertion of an intraarterial catheter (tail artery), mechanical ventilation is started. Baseline values of mean arterial blood pressure, arterial blood oxygen saturation, and heart rate are recorded.
The injection of lipopolysaccharides (1 milligram/kilogram body weight) dissolved in phosphate-buffered saline induces a strong and reproducible inflammatory response via the toll-like receptor 4. Fluid corrections as well as the application of norepinephrine are performed based on well-established protocols.
The animal model presented in this article is easy to learn and strongly oriented towards clinical sepsis treatment in an intensive care unit with sedation, mechanical ventilation, continuous blood pressure monitoring, and repetitive blood sampling. Also, the model is reliable, allowing for reproducible data with a limited number of animals in accordance with the 3R (reduce, replace, refine) principles of animal research. While animal experiments in sepsis research cannot easily replaced, repetitive measurements allow for a reduction of animals and keeping septic animals anesthetized diminishes suffering.

Here, we present a reproducible intensive care unit-oriented endotoxin model in rats.

一种可重复的重症监护病房导向内毒素模型在大鼠中的应用

Sepsis and septic shock remain the leading cause of death in intensive care units. Despite significant improvements in sepsis management, mortality still ...

Surfactant Depletion Combined with Injurious Ventilation Results in a Reproducible Model of the Acute Respiratory Distress Syndrome (ARDS)

Various animal models exist to study the complex pathomechanisms of the acute respiratory distress syndrome (ARDS). These models include pulmo-arterial infusion of oleic acid, infusion of endotoxins or bacteria, cecal ligation and puncture, various pneumonia models, lung ischemia/reperfusion models and, of course, surfactant depletion models, among others. Surfactant depletion produces a rapid, reproducible deterioration of pulmonary gas exchange and hemodynamics and can be induced in anesthetized pigs using repeated lung lavages with 0.9% saline (35 mL/kg body weight, 37 &#176;C). The surfactant depletion model supports investigations with standard respiratory and hemodynamic monitoring with clinically applied devices. But the model suffers from a relatively high recruitability and ventilation with high airway pressures can immediately reduce the severity of the injury by reopening atelectatic lung areas. Thus, this model is not suitable for investigations of ventilator regimes that use high airway pressures. A combination of surfactant depletion and injurious ventilation with high tidal volume/low positive end-expiratory pressure (high Tv/low PEEP) to cause ventilator induced lung injury (VILI) will reduce the recruitability of the resulting lung injury. The advantages of a timely induction and the possibility to perform experimental research in a setting comparable to an intensive care unit are preserved.

Surfactant Depletion Combined with Injurious Ventilation Results in a Reproducible Model of the Acute Respiratory Distress Syndrome ARDS

A combination of surfactant washout using 0.9% saline (35 mL/kg body weight, 37 &#176;C) and high tidal volume ventilation with low PEEP to cause moderate ventilator induced lung injury (VILI) results in experimental acute respiratory distress syndrome (ARDS). This method provides a model of lung injury with low/limited recruitability to study the effect of various ventilation strategies for extended periods.

表面活性剂耗竭与有害通风相结合导致急性呼吸窘迫综合症 （ARDS） 的可重复模型

Various animal models exist to study the complex pathomechanisms of the acute respiratory distress syndrome (ARDS). These models include pulmo-arterial ...

Porcine Liver Transplantation Without Veno-Venous Bypass As an Extended Criteria Donor Model

Liver transplantation is regarded as the gold standard for the treatment of a variety of fatal hepatic diseases. However, unsolved issues of chronic graft failure, ongoing organ donor shortages, and the increased use of marginal grafts call for the improvement of current concepts, such as the implementation of organ machine perfusion. In order to evaluate new methods of graft reconditioning and modulation, translational models are required. With respect to anatomical and physiological similarities to humans and recent progress in the field of xenotransplantation, pigs have become the main large animal species used in transplantation models. After the initial introduction of a porcine orthotopic liver transplant model by Garnier et al. in 1965, several modifications have been published over the past 60 years.
Due to specifies-specific anatomical traits, a veno-venous bypass during the anhepatic phase is regarded as a necessity to reduce intestinal congestion and ischemia resulting in hemodynamic instability and perioperative mortality. However, the implementation of a bypass increases the technical and logistical complexity of the procedure. Furthermore, associated complications such as air embolism, hemorrhage, and the need for a simultaneous splenectomy have been reported previously.
In this protocol, we describe a model of porcine orthotopic liver transplantation without the use of a veno-venous bypass. The engraftment of donor livers after static cold storage of 20 h - simulating extended criteria donor conditions - demonstrates that this simplified approach can be performed without significant hemodynamic alterations or intraoperative mortality and with regular uptake of liver function (as defined by bile production and liver-specific CYP1A2 metabolism). The success of this approach is ensured by an optimized surgical technique and a sophisticated anesthesiologic volume and vasopressor management.
This model should be of special interest for workgroups focusing on the immediate postoperative course, ischemia-reperfusion injury, associated immunological mechanisms, and the reconditioning of extended criteria donor organs.

In this protocol, a model of porcine orthotopic liver transplantation after static cold storage of donor organs for 20 h without the use of a veno-venous bypass during engraftment is described. The approach uses a simplified surgical technique with minimization of the anhepatic phase and sophisticated volume and vasopressor management.

无静脉-静脉旁路术的猪肝移植作为扩展标准供体模型

Liver transplantation is regarded as the gold standard for the treatment of a variety of fatal hepatic diseases. However, unsolved issues of chronic graft ...

Hemodynamic Precision in the Neonatal Intensive Care Unit using Targeted Neonatal Echocardiography

Targeted neonatal echocardiography (TnECHO) refers to the use of comprehensive echocardiographic evaluation and physiologic data to obtain accurate, reliable, and real-time information on developmental hemodynamics in sick newborns. The comprehensive assessment is based on a multiparametric approach that overcomes the reliability issues of individual measurements, allows for earlier recognition of cardiovascular compromise and promotes enhanced diagnostic precision and timely management. TnECHO-driven research has led to an enhanced understanding of the mechanisms of illness and the development of predictive models to identify at-risk populations. This information may then be used to formulate a diagnostic impression and provide individualized guidance for the selection of cardiovascular therapies. TnECHO is based on the expert consultative model in which a neonatologist, with advanced training in neonatal hemodynamics, performs comprehensive and standardized TnECHO assessments. The distinction from point of care ultrasonography (POCUS), which provides limited and brief one-time assessments, is important. Neonatal hemodynamics training is a 1-year structured program designed to optimize image acquisition, measurement analysis, and hemodynamic knowledge (physiology, pharmacotherapy) to support cardiovascular decision-making. Neonatologists with hemodynamic expertise are trained to recognize deviations from normal anatomy and appropriately refer cases of possible structural abnormalities. We provide an outline of neonatal hemodynamics training, the standardized TnECHO imaging protocol, and an example of representative echo findings in a hemodynamically significant patent ductus arteriosus.

Presented here is a protocol to perform comprehensive neonatal echocardiography by trained neonatologists in the neonatal intensive care unit. The trained individuals provide longitudinal assessments of heart function, systemic and pulmonary hemodynamics in a consultative role. The manuscript also describes the requirements to become a fully trained neonatal hemodynamics specialist.

使用靶向新生儿超声心动图在新生儿重症监护病房中测定血流动力学精度

Targeted neonatal echocardiography (TnECHO) refers to the use of comprehensive echocardiographic evaluation and physiologic data to obtain accurate, ...

使用 M-ROSE 加强肺部感染治疗

Microbiological Rapid On-Site Evaluation for Pulmonary Infectious Diseases

The prompt initiation of empirical anti-infective therapy is crucial in patients presenting with unexplained pulmonary infection. Although imaging acquisition is relatively straightforward in clinical practice, its lack of specificity often necessitates additional time-consuming tests such as sputum culture, bronchoalveolar-lavage fluid culture, or genetic sequencing to identify the underlying etiology of the disease accurately. Moreover, the limited efficacy of empirical anti-infective treatment may contribute to antibiotic misuse. Recent advancements in interpreting microbial background on rapid on-site evaluation (ROSE) slides have enabled clinicians to promptly obtain samples through bronchoscopy (e.g., alveolar lavage, mucosal brushing, tissue clamp), facilitating bedside staining and interpretation that provides essential microbial background information. Consequently, this establishes a foundation for developing targeted anti-infection treatment and individualized drug therapy plans. With a better understanding of which pathogens are causing infections in real-time, physicians can avoid unnecessary broad-spectrum antibiotics contributing to antibiotic resistance. Establishing a rapid and standardized M-ROSE workflow within respiratory medicine departments or intensive care units will greatly assist physicians in formulating accurate treatment strategies for patients, which holds significant clinical implications.

作者聚焦：使用 M-ROSE 实时推进病原体检测和疾病评估

The protocol here demonstrates a fast and standardized microbiological rapid on-site evaluation (M-ROSE) workflow, including three steps: slide making, staining, and interpretation. This protocol will help physicians make rapid clinical decisions.