本研究中涉及人类参与者的所有程序均符合机构和/或国家研究委员会的伦理标准以及 1964 年赫尔辛基宣言及其后来的修正案或类似的伦理标准。根据超声医师的喜好，可以使用扇形阵列（有时通俗地称为“相控阵”）或低频曲线换能器进行检查。对于图形和扫描，曲线探头用于前矢状面视图，而扇形阵列探头用于胃体扫描。探头的商业细节在 材料表中提供。
1.剑突下矢状胃窦视图（又名“剑突下视图”）
<ol><li>仰卧位视图<ol><li>患者体位：将患者置于仰卧位。如果患者无法忍受完全仰卧位，则最多 30 度的抬头是可以接受的选择。</li>
		<li>探头选择：选择任何低频探头（例如，曲线或扇形阵列）（参见 材料表）。</li>
		<li>模式选择：将预设设置为腹部模式。</li>
		<li>探头放置<ol><li>将探头放在矢状面的患者剑突下区域（图1）。</li>
			<li>将探针标记定向至头侧方向。</li>
		</ol></li>
		<li>图像优化<ol><li>将探头从左向右扇动，直到可以在屏幕上看到以下结构：（1）屏幕左侧的肝脏;（2）图像中长轴深处的搏动性主动脉;（2）胃窦位于尾部，深至肝浅缘（图2）。</li>
			<li>确保腹主动脉位于图像的较深边缘。如果看到下腔静脉 （IVC），如果向患者右侧倾斜得太远，则校正超声束角。在这种情况下，在幽门水平而不是胃窦水平上可视化胃。如果发生这种情况，请向左扇动，直到主动脉变得可见。这是分析胃窦的合适位置（图3）。 注意：如果在IVC水平上只看到胃而不是主动脉，则定性超声数据仍然很有价值，但请记住，这种观点对检测“高风险”胃的敏感性较低。在这种情况下，容量评估可能会低估胃容量（图 3）。</li>
			<li>识别固有肌层（低回声，最厚的胃壁层），以确保聚焦在胃上。大而扩张的肠可能被误认为是胃窦（图4）。 注意：胰腺可能在胃窦后方可见（图2）。</li>
		</ol></li>
		<li>图像采集：单击 “获取 ”以保存此超声视图的视频剪辑。</li>
	</ol></li>
	<li>右侧卧位褥疮视图<ol><li>患者体位：将患者置于右侧卧位（图 5）。</li>
		<li>探头选择：按照步骤 1.1.2 操作。</li>
		<li>模式选择：按照步骤 1.1.3 操作。</li>
		<li>探头放置：按照步骤 1.1.4 进行操作。</li>
		<li>图像优化：按照步骤 1.1.5 操作。</li>
		<li>图像采集：按照步骤 1.1.6 操作。</li>
		<li>胃体积的定量估计<ol><li>如果胃窦似乎只含有透明液体，则通过获取如上所述的胃窦图像来量化胃总容积，患者处于 RLD 位置（参见步骤 1.2.5）。</li>
			<li>当在胃窦最大扩张期间获得胃窦的视图时，冻结图像。</li>
			<li>激活追踪工具并沿着代表浆膜的壁的外高回声层 追踪 胃窦的横截面积（图6）。 注意：胃窦面积大于 10 cm2不太可能与正常基线体积一致，并提示“饱腹”。</li>
			<li>点击 保存。</li>
			<li>使用以下公式13 估计胃液体积：胃容量 （mL） = 27 + 14.6 ACSA（以 RLD 为单位）cm2 − 1.28 x 年龄（岁）。 注意：该配方已针对胃窦中的透明液体进行了验证。该公式也在一项针对病态肥胖个体的单独研究中得到了验证14.</li>
		</ol></li>
	</ol></li>
</ol>2. 左上腹 （LUQ） 胃体视图
<ol><li>如果剑突下视图不充分或无法访问，请继续评估左上象限视图（步骤 2.2 和步骤 2.3）。</li>
	<li>LUQ 冠状胃体视图<ol><li>患者体位：遵循步骤 1.1.1。</li>
		<li>探头选择：按照步骤 1.1.2 操作。</li>
		<li>模式选择：按照步骤 1.1.3 操作。</li>
		<li>探头定位<ol><li>将探头放在纵向平面的左腋中线上，方向标记指向患者的头部（图7）。 注意： 当探针标记朝向这个方向时，胸腔将出现在超声扫描仪的左侧，右侧将是腹腔。</li>
		</ol></li>
		<li>图像优化<ol><li>识别脾脏和左半膈肌。脾脏由其圆形的荚膜形状来识别。左半膈肌表现为高回声线，高于脾脏，并随着正常的呼吸周期而移动。</li>
			<li>一旦确定了脾脏，向后扇动以识别肾脏，肾脏将表现为脾脏下方和后方的长方形结构。 注意：脾脏提供的声学窗口比肝脏在右腹部提供的声学窗口少</li>
			<li>一旦确定了这些标志，将换能器向前倾斜以获得胃体的视图（图7）。 注意：解剖结构可能会随着横膈膜的移动而移动。如果可能，请考虑要求患者在进行扫描时短暂屏住呼吸。</li>
		</ol></li>
		<li>按照步骤 1.1.6 获取图像。</li>
	</ol></li>
	<li>LUQ前横胃体视图<ol><li>患者体位：遵循步骤 1.1.1。</li>
		<li>探头选择：按照步骤 1.1.2 操作。</li>
		<li>模式选择：按照步骤 1.1.3 操作。</li>
		<li>探头定位<ol><li>将探头放在患者腹部前表面的锁骨中线附近，就在肋骨的尾部（图8）。为了全面评估胃体，可能需要将探头顺时针旋转至倾斜视图。</li>
		</ol></li>
		<li>图像优化：将探头从颅向尾部扇动，直到看到胃体深入脾脏。</li>
		<li>按照步骤 1.1.6 获取图像。</li>
	</ol></li>
</ol>

胃超声技术减轻围手术期误吸风险

<ol>
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YB 是美国麻醉医师协会床旁超声编辑委员会的编辑，也是 POCUS OpenAnesthesia.org 的部分编辑。SH 是美国麻醉医师协会床旁超声编辑委员会的主编。AP 是美国麻醉医师协会床旁超声编辑委员会的编辑。她还为FujioFilm Sonosite提供咨询工作。

如前所述，胃超声的主要目的是在气道管理或程序镇静之前评估胃内容物并评估风险。提供的协议概述了捕获胃窦和身体图像的两种主要方法，有助于进行这种风险评估。此外，查看代表性结果部分有助于胃超声医师发展图像解释技能。虽然对医疗决策的全面讨论超出了该协议的范围，但本手稿将解决局限性、需要进一步探索的特定临床场景、挑战、未解决的问题以及能力所需的最低培训水平。<...

胃内容物的肺部误吸可引起肺炎、肺炎，甚至死亡1.较高的体积、颗粒物的存在和较高的抽吸酸度已被证明会增加这种情况的严重程度。许多因素有助于指导临床医生评估误吸风险，包括可能减慢胃排空时间的合并症、机械性胃肠道梗阻和最后一次经口摄入的时间。从历史上看，后者仅依赖于对患者病史的评估，这可能是不可靠和不准确的。此外，临床医生的判断力已被证明在诊断饱腹时很差，无法公平2.
2011 年，美国麻醉学会 （ASA） 任命的一个特别工作组首次发布了术前禁食指南，并于 2017 年更新了这些指南 3,4。尽管 ASA 禁食指南是有帮助的，但它们是基于人群的，并非针对特定临床情况量身定制，并且建议对病理改变的患者（例如胃排空延迟或肠梗阻）进一步考虑。此外，这些指南依赖于一位准确的历史学家，并且能够正确回忆起他们最后一次经口摄入量的患者。最后，指南建议的禁食间隔可能不足以确保在紧急情况或紧急情况下空腹。
为了解决已发表的禁食指南中的空白并识别有误吸高风险的患者，胃部诊断性床旁超声 （POCUS） 成像方案已由两个独立的作者组开发和验证：一组由重症监护病房 （ICU） 医生组成，另一组由麻醉师组成。ICU第 5 组专注于需要紧急气管插管的危重患者，并开发了一种通过左上象限 （LUQ） 评估胃来筛查这些患者胃胀气的方法。在LUQ中，作者使用脾脏作为超声窗口，在冠状面和横平面上可视化胃体，以筛查胃膨胀的定性体征。当发现大胃胀气时，作者采取了特殊的气道预防措施，以尽量减少误吸的机会（例如，在诱导全身麻醉和气管插管之前放置鼻胃管进行胃减压[如果没有禁忌证]）。另外，一组专注于围手术期患者的麻醉师开发了一种筛查胃内容物的技术，这在正常胃排空的适当禁食患者中是无法预期的6.该技术涉及将超声探头放置在上腹部的矢状面上以可视化胃窦。该技术既可以定性检测高危胃内容物，也可以在清澈液体的情况下定量估计胃液量。
通过将这两种方案结合成混合方法，本手稿将遵守 I-AIM 框架对胃超声检查的关键步骤进行分类：适应症、采集、图像解释和医疗决策7。然而，由于本特辑的重点是诊断性 POCUS 图像解释，因此本手稿将仅简要介绍图像解释，并将在很大程度上推迟对医疗决策的讨论，因为这超出了本集的范围。
迹象 胃超声至少有四种可能的适应证。首先，在患者胃容量和/或内容物未知或胃容量/内容物病史不可靠的情况下，在插管或程序镇静之前进行胃超声筛查高危胃内容物。在这种情况下，进行胃超声检查以对肺部误吸的可能性进行风险分层，并调整患者的护理以最大限度地降低这种风险。其次，一些重症监护医生使用胃超声来测量接受肠内喂养的患者的胃残余容积 （GRV）8。在这种情况下，评估胃窦有助于诊断肠内喂养不耐受，从而降低吸入性肺炎的风险。最近，胃超声检查已被评估为测量窦横截面积的工具，并显示出与 ICU 患者 GRV 的强相关性9。第三，胃 POCUS 已被用于评估外科手术后患者的肠功能延迟和术后肠梗阻10.第四，在儿科患者中，胃超声已被用于诊断异物摄入和幽门狭窄等病理11.对于胃超声的其他儿科应用，读者可参考其他来源。本文的其余部分将重点介绍成人11 的胃超声检查。
胃超声的禁忌症很少，因为该检查是一种非侵入性检查，对患者的直接伤害可以忽略不计。主要的绝对禁忌症是患者拒绝。相对禁忌症包括以下任何一种：（1） 通常扫描窗口区域的敷料/伤口;（2）由于患者的血流动力学或临床状态迅速恶化而没有时间尝试检查;（3）胃饱的预测试概率非常高或非常低。幸运的是，干预敷料/伤口的存在有时可以通过选择替代超声检查窗口来解决。例如，如果前腹入路受阻，可以尝试左侧位，反之亦然。时间不足也可以通过刻意练习来控制，因为研究表明，胃超声可以在专家手中迅速进行12.最后，在某些情况下，胃饱腹的验前概率要么非常低（例如，健康患者在手术前适当禁食）要么非常高（例如，患者出现已知的固定肠梗阻）。在这种情况下，胃超声是相对禁忌的，因为该测试与所有诊断测试一样，并不完美，并且有可能产生假阳性和假阴性结果，从而导致患者走向不适当的方向。
收购 对于采集，建议从剑突下矢状面入路开始，以可视化胃窦。胃窦是测量胃内容物的最佳解剖位置，因为它具有一致的浅表位置。它构成了胃中最依赖的部分，在大多数患者中可以快速识别6.此外，胃窦随着内容物的增加而线性扩张，使其成为定性评估胃内容物的合适靶标，并建议胃抽吸的风险分层6。如果前矢状窗无法触及（例如，由于伤口/敷料）或提供不确定的数据，左侧侧窗可以提供有关患者胃内容物的有用定性数据。
关于图像解释和医疗决策，该手稿回顾了一系列潜在结果，并解释了胃超声如何在不同的患者群体中协同使用。最后，将描述这些方法的常见缺陷和局限性。

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>High Frequency Ultrasound Probe (HFL38xp)</td>
			<td>SonoSite (FujiFilm)</td>
			<td>P16038</td>
			<td></td>
		</tr>
		<tr>
			<td>Low Frequency Ultrasound Probe (C35xp)</td>
			<td>SonoSite (FujiFilm)</td>
			<td>P19617</td>
			<td></td>
		</tr>
		<tr>
			<td>SonoSite X-porte Ultrasound</td>
			<td>SonoSite (FujiFilm)</td>
			<td>P19220</td>
			<td></td>
		</tr>
		<tr>
			<td>Ultrasound Gel</td>
			<td>AquaSonic</td>
			<td>PLI 01-08</td>
			<td></td>
		</tr>
	</tbody>
</table>

gastric point of care ultrasound in adults: image acquisition and interpretation

在过去的二十年中，诊断性床旁超声 （POCUS） 已成为一种快速且无创的床边工具，用于解决与胃内容物相关的临床查询。对于即将接受镇静和/或气管插管的患者，一个新出现的问题：患者胃内容物误吸的风险增加。胃内容物吸入肺部会造成严重且可能危及生命的并发症。当胃被认为是“饱”时，这种情况会更频繁地发生，并且可能受到用于气道管理的技术的影响，从而有可能预防。为了降低围手术期误吸的风险，两个不同的医学专业（麻醉学和重症监护医学）独立开发了利用超声检查来识别需要“全胃”预防措施的患者的技术。由于这些不同的专业，每个小组的工作在各自领域之外仍然相对陌生。本文介绍了两种胃超声技术。此外，它还解释了当其中一种方法不足时，这些方法如何相互补充。关于图像采集，本文涵盖以下主题：适应症和禁忌症、适当探头的选择、患者定位和故障排除。本文还深入探讨了图像解释，并附有示例图像。此外，它还演示了如何采用这两种技术中的一种来估计胃液量。最后，本文简要讨论了基于本次检查结果的医疗决策。

为确保胃窦的准确可视化，有必要探查足够深以识别主动脉。相反，检测 IVC 将扫描置于胃幽门水平，导致结果低估了真正的胃内容物。虽然胃幽门水平的诊断效用仍然存在，但与胃窦视图相比，解释起来不那么简单（图 3）。因此，一项关键任务是扫描大血管并区分胃窦和幽门（图9）。主动脉可通过其厚而脉动的壁来识别，与IVC不同。必要时，可利?...

Watch this Scientific Journal Video about Point-of-Care Ultrasound for Gastric Content Assessment and Risk Stratification in Perioperative Care at JoVE.com

作者聚焦：用于围手术期护理中胃内容物评估和风险分层的床旁超声 

该协议介绍了两种在胃超声检查中获取图像的方法。此外，还提供了解释这些信息以帮助医疗决策的提示。

成人胃旁超声：图像采集和解释

Over the past two decades, diagnostic point-of-care ultrasound (POCUS) has emerged as a rapid and non-invasive bedside tool for addressing clinical ...

目前的 NPO 指南并未专门针对胃排空延迟或肠梗阻患者。利用床旁超声评估胃内容物，使提供者能够获得有关这些患者的更准确信息，并适当地对他们进行肺部误吸的可能性进行风险分层。这些方案有望使围手术期从业者更好地评估需要镇静或气管插管的患者的胃内容物。有了更准确的数据，从业者将能够更好地进行风险分层并最大限度地减少肺部误吸的可能性。该协议的部分内容将用于研究独特患者群体的胃排空模式，例如患有糖尿病、肠梗阻、食管裂孔疝或正在服用新型药物胰高血糖素样肽-1 受体激动剂的患者。

gastric-point-care-ultrasound-adults-image-acquisition

Research

JoVE Journal

Medicine

Gastric Point of Care Ultrasound in Adults: Image Acquisition and Interpretation

2.4K 次观看.  George Washington University. 目前的 NPO 指南并未专门针对胃排空延迟或肠梗阻患者。利用床旁超声评估胃内容物，使提供者能够获得有关这些患者的更准确信息，并适当地对他们进行肺部误吸的可能性进行风险分层。这些方案有望使围手术期从业者更好地评估需要镇静或气管插管的患者的胃内容物。有了更准确的数据，从业者将能够更好地进行风险分层并最大限度地减少肺部误吸的可能性。该协?...

视频: 作者聚焦：用于围手术期护理中胃内容物评估和风险分层的床旁超声 

Troubleshooting FoCUS Image Acquisition: Patient Positioning, Transducer Manipulation, and Image Optimization

Focused cardiac ultrasound (FoCUS) is a limited, clinician-performed application of echocardiography to add real-time information to patient care. These bedside exams are problem oriented, rapidly and repeatedly performed, and largely qualitative in nature. Competency in FoCUS includes mastery of the stereotactic and psychomotor skills required for transducer manipulation and image acquisition. Competency also requires the ability to optimize the setup, troubleshoot image acquisition, and understand the sonographic limitations because of complex clinical environments and patient pathology. This article presents concepts for successful, high-quality two-dimensional (B-mode) image acquisition in FoCUS.
Concepts of high-quality image acquisition can be applied to all established sonographic windows of the FoCUS exam: the parasternal long-axis (PLAX), parasternal short-axis (PSAX), apical four chamber (A4C), subcostal fourchamber (SC4C), and the inferior vena cava (IVC). The apical five-chamber (A5C) and subcostal short-axis (SCSA) views are mentioned, but are not discussed in-depth. A pragmatic figure illustrating the movements of the phased array transducer is also provided to serve as a cognitive aid during FoCUS image acquisition.

Here, we present a protocol to allow providers to perform focused cardiac ultrasound (FoCUS) in the clinical environment. We describe methods of transducer manipulation, review common pitfalls of transducer movements, and suggest tips to optimize phased array transducer use.

FoCUS 图像采集故障排除：患者定位、换能器操作和图像优化

Focused cardiac ultrasound (FoCUS) is a limited, clinician-performed application of echocardiography to add real-time information to patient care. These ...

科研

医学

Point-of-Care Lung Ultrasound in Adults: Image Acquisition

Consultative ultrasound performed by radiologists has traditionally not been used for imaging the lungs, as the lungs&#39; air-filled nature normally prevents direct visualization of the lung parenchyma. When showing the lung parenchyma, ultrasound typically generates a number of non-anatomic artifacts. However, over the past several decades, these artifacts have been studied by diagnostic point-of-care ultrasound (POCUS) practitioners, who have identified findings that have value in narrowing the differential diagnoses of cardiopulmonary dysfunction. For instance, in patients presenting with dyspnea, lung POCUS is superior to chest radiography (CXR) for the diagnosis of pneumothorax, pulmonary edema, lung consolidations, and pleural effusions. Despite its known diagnostic value, the utilization of lung POCUS in clinical medicine remains variable, in part because training in this modality across hospitals remains inconsistent. To address this educational gap, this narrative review describes lung POCUS image acquisition in adults, including patient positioning, transducer selection, probe placement, acquisition sequence, and image optimization.

Point-of-care ultrasound (POCUS) of the lungs provides quick answers in rapidly changing clinical scenarios. We present an efficient and informative protocol for image acquisition for use in acute care settings.

成人床旁肺部超声：图像采集

Consultative ultrasound performed by radiologists has traditionally not been used for imaging the lungs, as the lungs&#39; air-filled nature normally ...

Point-of-Care Ultrasound: A Review of Ultrasound Parameters for Predicting Difficult Airways

Airway management remains a crucial part of perioperative care. The conventional approach to assessing potentially difficult airways emphasizes the LEMON method, which looks for and evaluates the Mallampati classification, signs of obstruction, and neck mobility. Clinical findings help predict a higher likelihood of difficult tracheal intubation, but no clinical result reliably excludes difficult intubation. Ultrasound as an adjunct to clinical examination can provide the clinician with a dynamic anatomical airway assessment, which is impossible with clinical examination alone. In the hands of anesthesiologists, ultrasound is becoming more popular in the perioperative period. This method is particularly applicable for identifying proper endotracheal tube positioning in specific patient populations, such as those who are morbidly obese and patients with head and neck cancer or trauma. The focus is on identifying the normal anatomy, correctly positioning the endotracheal tube, and refining the parameters that predict difficult intubation. Several ultrasound measurements are clinical indicators of difficult direct laryngoscopy in the literature. A meta-analysis revealed that the distance from the skin to the epiglottis (DSE) is most associated with a difficult laryngoscopy. An ultrasound of the airway could be applied in routine practice as an adjunct to the clinical examination. A full stomach, rapid sequence intubation, gross visual anatomical abnormalities, and restricted neck flexibility prevent using ultrasound to assess the airway. The airway evaluation is performed with a linear array transducer of 12-4 MHz, with the patient in the supine position, with no pillow, and with the head and neck in a neutral position. The central axis of the neck is where the ultrasound parameters are measured. These image acquisitions guide the standard ultrasound examination of the airway.

A point-of-care ultrasound (POCUS) is a simple, non-invasive, and portable tool that enables dynamic airway assessment. Several studies have attempted to determine the role of ultrasound parameters as an adjunct to clinical examination in predicting difficult laryngoscopies.

床旁超声：预测困难气道的超声参数综述

Airway management remains a crucial part of perioperative care. The conventional approach to assessing potentially difficult airways emphasizes the LEMON ...

A Modified Sonographic Algorithm for Image Acquisition in Life-Threatening Emergencies in the Critically Ill Newborn

The use of routine point-of-care ultrasound (POCUS) is increasing in neonatal intensive care units (NICUs), with several centers advocating for 24 h equipment availability. In 2018, the sonographic algorithm for life-threatening emergencies (SAFE) protocol was published, which allows the assessment of neonates with sudden decompensation to identify abnormal contractility, tamponade, pneumothorax, and pleural effusion. In the study unit (with a consulting neonatal hemodynamics and POCUS service), the algorithm was adapted by including consolidated core steps to support at-risk newborns, aiding clinicians in managing cardiac arrest, and adding views to verify correct intubation. This paper presents a protocol that can be applied in the NICU and the delivery room (DR) in relation to three scenarios: cardiac arrest, hemodynamic deterioration, or respiratory decompensation. 
This protocol can be performed with a state-of-the-art ultrasound machine or an affordable handheld device; the image acquisition protocol is carefully detailed. This method was designed to be learned as a general competence to obtain the timely diagnosis of life-threatening scenarios; the method aims to save time but does not represent a substitute for comprehensive and standardized hemodynamic and radiological analyses by a multidisciplinary team, which might not universally be on call but needs to be involved in the process. From January 2019 to July 2022, in our center, 1,045 hemodynamic consultation/POCUS consults were performed with 25 patients requiring the modified SAFE protocol (2.3%), and a total of 19 procedures were performed. In five cases, trained fellows on call resolved life-threatening situations. Clinical examples are provided that show the importance of including this technique in the care of critical newborns.

Here, we present a protocol that can be applied in the neonatal intensive care unit and the delivery room in relation to three scenarios: cardiac arrest, hemodynamic deterioration, or respiratory decompensation. This protocol can be performed with a state-of-the-art ultrasound machine or an affordable handheld device; an image acquisition protocol is carefully detailed.

一种改进的超声算法，用于危重新生儿危及生命的急症图像采集

The use of routine point-of-care ultrasound (POCUS) is increasing in neonatal intensive care units (NICUs), with several centers advocating for 24 h ...

Optic Nerve Sheath Point of Care Ultrasound: Image Acquisition

The goal of this protocol is to develop a standardized method for acquiring images of the optic nerve sheath and measuring the optic nerve sheath diameter (ONSD). Diagnostic ultrasound of the ONSD to detect intracranial hypertension has traditionally faced many problems because of methodologic discrepancies. Due to inconsistencies in the measuring techniques, the potential for ONSD to become a non-invasive bedside monitoring tool for ICP has been hampered. However, establishing a transparent, consistent methodology for measuring the ONSD would support its use as a valid and reliable method of identifying intracranial hypertension. This is important as it has both high sensitivity and specificity in acute care settings. This narrative review describes ONSD POCUS image acquisition, including patient positioning, transducer selection, probe placement, the acquisition sequence, and image optimization. Further, visual aids are provided to assist in real-time during image acquisition. This method should be considered for patients for whom there are concerns regarding intracranial hypertension but who do not have an intracranial monitor in place.

Point-of-care ultrasound (POCUS) of the optic nerve sheath diameter (ONSD) has been shown to be useful in identifying patients with increased intracranial pressure (ICP). However, the non-standardized technique for this POCUS has hampered its use. We present a standardized image acquisition protocol for use in the acute care setting.

视神经鞘床旁超声：图像采集

The goal of this protocol is to develop a standardized method for acquiring images of the optic nerve sheath and measuring the optic nerve sheath diameter ...

使用床旁超声对腹主动脉进行成像

An Approach to Point-Of-Care Ultrasound Evaluation of the Abdominal Aorta

Disorders of the abdominal aorta, including aneurysms and dissection, have potentially high rates of morbidity and mortality. While computed tomography (CT) is the current gold standard to image the abdominal aorta, the process of obtaining a CT may be time-consuming, requires the use of intravenous contrast dye, and involves exposure to ionizing radiation. Point-of-care Ultrasound (POCUS) can be performed at the bedside and has excellent sensitivity and specificity for the diagnosis of abdominal aortic aneurysm and excellent specificity for the diagnosis of abdominal aortic dissection. Additionally, POCUS is non-invasive, cost-effective, lacks ionizing radiation, requires no intravenous contrast dye, and can be performed without taking the patient from a critical care area. Screening for abdominal aortic aneurysm (AAA) can be done in primary care settings as well. 
This article will review the approach to POCUS of the abdominal aorta to evaluate such critical pathology. In this paper, we will review the sonographic anatomy of the abdominal aorta as well as the choice of the ultrasound probe, description of POCUS image acquisition, and some pearls and pitfalls of using POCUS to aid in the diagnosis of potentially life-threatening abdominal aortic pathology.

作者聚焦：使用床旁超声全面评估腹主动脉

This protocol reviews the steps to image the abdominal aorta with point-of-care ultrasound. We discuss image acquisition, troubleshooting imaging pitfalls and artifacts, and the recognition of life-threatening abdominal aortic pathology.

腹主动脉床旁超声评估方法

Disorders of the abdominal aorta, including aneurysms and dissection, have potentially high rates of morbidity and mortality. While computed tomography ...

超声评估膈肌功能障碍和监测治疗

Measuring Diaphragm Thickness and Function Using Point-of-Care Ultrasound

The diaphragm is the main component of the respiratory muscle pump. Diaphragm dysfunction can cause dyspnea and exercise intolerance, and predisposes affected individuals to respiratory failure. In mechanically ventilated patients, the diaphragm is susceptible to atrophy and dysfunction through disuse and other mechanisms. This contributes to failure to wean and poor long-term clinical outcomes. Point-of-care ultrasound provides a valid and reproducible method for evaluating diaphragm thickness and contractile activity (thickening fraction during inspiration) that can be readily employed by clinicians and researchers alike. This article presents best practices for measuring diaphragm thickness and quantifying diaphragm thickening during tidal breathing or maximal inspiration. Once mastered, this technique can be used to diagnose and prognosticate diaphragm dysfunction, and guide and monitor response to treatment over time in both healthy individuals and acute or chronically ill patients.

作者聚焦：揭示机械通气对隔膜功能和患者预后的影响 

Diaphragm thickness and function can be assessed in healthy individuals and critically ill patients using point-of-care ultrasound. This technique offers an accurate, reproducible, feasible, and well-tolerated method for evaluating diaphragm structure and function.

使用床旁超声测量隔膜厚度和功能

The diaphragm is the main component of the respiratory muscle pump. Diaphragm dysfunction can cause dyspnea and exercise intolerance, and predisposes ...

Methods Article

成人胃旁超声：图像采集和解释