None. No funding was received for this project.

These studies were approved by the George Washington University Institutional Review Board (IRB # NCR203147). The study subject for all procedures described below (and pictured in figures) was a 32-year-old male who gave full informed consent to the study and publication of de-identified images. Inclusion criteria include any patient undergoing airway management or anesthetic care (especially those who have characteristics of a difficult airway) and exclusion criteria would include any patient who does not consent to this procedure.
1. Differentiating esophageal from endotracheal intubation
<ol>
	<li>Prior to the induction of general anesthesia, prepare a high frequency, linear ultrasound probe (see Table of Materials) by placing a single layer of ultrasound gel (see Table of Materials) to the probe transducer. Select the linear probe from the transducer menu on the touchscreen and specify MSK (musculoskeletal) from the dropdown menu. Place the ultrasound in scanning mode by pushing the 2D button on the bottom left corner of the touchscreen. Induce general anesthesia as recommended by the attending anesthesiologist.</li>
	<li>Following the induction of general anesthesia,place the probe in the transverse position on the midline of the patient&#39;s anterior neck just cephalad to the suprasternal notch (Figure 1A). Ensure the probe marker is on the left of the screen on the ultrasound instrument (see Table of Materials).</li>
	<li>Identify the trachea midline and note the constricted esophagus just lateral to the trachea (Figure 1B). For further anatomic confirmation, scan laterally to identify the carotid artery and internal jugular vein if necessary.</li>
	<li>Check for obvious tracheal and surrounding tissue movement associated with intubation as the endotracheal tube moves into the trachea. In the event that tracheal movement is not observed, slightly twist the endotracheal tube to attempt to generate movement on the ultrasound image.
	<ol>
		<li>Additionally, check that the hyperechoic, posterior aspect of the trachea disappears due to the endotracheal tube, leaving a characteristic acoustic shadowing that is bullet shaped (this is called the &#34;bullet sign&#34;, shown in Figure 2). If, instead, there is an esophageal intubation, there will be obvious tissue movement to the left of the trachea, and there will now be two lumens. This is called &#34;double track sign,&#34; and there will be two air/mucosal interfaces (Figure 3). 
		NOTE: Use this ultrasound technique in real-time intubations to obtain immediate feedback as to whether the tube is being placed in the trachea or the esophagus. In addition, consider using this technique during emergency airway management, where end tidal carbon dioxide confirmation may not be reliable due to poor pulmonary blood flow17.</li>
	</ol>
	</li>
</ol>
2. Identifying the cricothyroid membrane in preparation for a cricothyrotomy
NOTE: For emergency airway management, a cricothyrotomy might be a necessary step if the provider encounters a &#34;cannot intubate, cannot oxygenate&#34; scenario. In the event a difficult airway situation is suspected, the provider may opt to identify the CTM prior to the induction of anesthesia, in case it might be required to perform a cricothyrotomy.
<ol>
	<li>Perform CTM identification with the patient lying in the supine position and the neck extended. Prepare the ultrasound probe as described in step 1.1. As the CTM is shallow in the neck, place the probe to a depth of approximately 1.5-2 cm based on an average-sized patient. 
	NOTE: There are two methods for utilizing ultrasound to locate the CTM.</li>
	<li>Perform the first method to locate the CTM as described below.
	<ol>
		<li>Place a linear, high frequency probe in the sagittal plane of the patient&#39;s neck just caudal to the thyroid cartilage (Figure 4A). The thyroid cartilage appears as the superficial, hypoechoic structure at the cranial side of the scan and casts an acoustic shadow (Figure 4B).</li>
		<li>Next, locate the cricoid cartilage, which is in a caudal location and appears hypoechoic. Identify the CTM lying between these two structures using the underlying air-mucosal interface, which appears as a hyperechoic line that runs the length of the trachea.</li>
		<li>For further confirmation, scan caudal to locate the tracheal rings, which will appear as a hyperechoic &#34;string of beads&#34;18. 
		NOTE: The second technique for identifying the CTM (step 2.5 to step 2.8) involves using a transverse scanning orientation on the anterior neck. This technique is sometimes referred to as the thyroid-airline-cricoid-airline (TACA) approach19.</li>
	</ol>
	</li>
	<li>Perform the second technique to locate the CTM as described below.
	<ol>
		<li>Begin by placing a linear high frequency probe in the transverse plane at the level of the thyroid cartilage, which appears as hyperechoic and casts an acoustic shadow-a black triangle with the tip being most superficial (Figure 5).</li>
		<li>Scan in a caudal direction until the black triangle disappears as the thyroid cartilage ends and the CTM begins. Identify this as the air-mucosal interface that appears as a bright white line with reverberation effects (Figure 5).</li>
		<li>Continue scanning in a caudal direction until the CTM ends and the cricoid cartilage appears. The cricoid cartilage will appear as a hypoechoic band surrounding the trachea (Figure 5). Once the cricoid is identified, the sonographer will have located the inferior border of the CTM.</li>
		<li>To ensure that the proper anatomy has been identified, reverse these steps and scan in a cephalad direction, again identifying the CTM and the thyroid cartilage. Once these landmarks have been identified, mark the CTM location on the patient. Once the CTM has been marked, proceed to the induction of anesthesia and airway management as planned, knowing the CTM is properly identified in the rare event a surgical airway is required.</li>
	</ol>
	</li>
</ol>
3. Acquisition of parameters for the prediction of difficult airway management
NOTE: For the prediction of difficult airway management, the skin to epiglottis distance and LPWT are measured. These steps should be performed prior to the induction of anesthesia.
<ol>
	<li>To measure the skin to epiglottis distance, place the patient in the supine position with the neck in a neutral position and prepare the probe and ultrasound as described in step 1.1.
	<ol>
		<li>Place a high frequency, linear probe in the transverse position on the anterior neck at the level of the thyrohyoid membrane (Figure 6A).</li>
		<li>Identify the epiglottis, which appears as the hypoechoic structure midway between the hyoid bone and thyroid cartilage (Figure 6B). The laryngeal surface of the epiglottis forms a hyperechoic line, which represents the air-mucosal interface. Tilt the probe in either direction if the anterior border of the epiglottis is not clearly defined.</li>
		<li>Note an echogenic (fat-filled) pre-epiglottic space20.</li>
		<li>To measure the skin to epiglottis distance, freeze the image by touching the large Freeze button at the bottom of the touchscreen. Next, select the blue Distance button on the right side of the screen. Use a finger to drag one cursor to the superficial surface of the epiglottis, and move the other cursor to the anterior surface of the neck (skin). The skin to epiglottis distance will be displayed in the gray box on the upper left side of the screen. 
		NOTE: Based on this measurement, it is possible to predict difficult intubation. A skin to epiglottis distance greater than 2.7 cm indicates that a Cormacke-Lehane score of 3 or 4 may be encountered on direct laryngoscopy21.</li>
	</ol>
	</li>
	<li>To measure the LPWT, place the patient in the supine position with the neck in neutral orientation.
	<ol>
		<li>Place a curvilinear, low-frequency probe in the coronal orientation below the mastoid process and in-line with the carotid artery (Figure 7A).</li>
		<li>Use doppler flow to identify the carotid artery. To accomplish this, press the C button on the bottom left of the screen. Using a finger on the touch screen, move the yellow box over the carotid vasculature. Identify the carotid artery by noting the pulsatile vascular flow.</li>
		<li>To measure the LPWT, freeze the image (Figure 7B) by pushing the Freeze button on the bottom of the screen. Then press the blue Distance button on the right side of the screen. Place one cursor on the inferior border of the carotid artery and the second cursor on the anterior aspect of the airway. The LPWT will then be displayed in the gray box on the upper left side of the screen. 
		NOTE: In the event of an emergency airway scenario requiring rapid sequence induction, step 3.2 may be skipped, as mask ventilation is not likely to be necessary, and in the interest of time.</li>
	</ol>
	</li>
</ol>

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H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Sonographic+measurement+of+lateral+parapharyngeal+wall+thickness+in+patients+with+obstructive+sleep+apnea.">Sonographic measurement of lateral parapharyngeal wall thickness in patients with obstructive sleep apnea.</a> Sleep. 30 (11), 1503-1508 (2022).</li><li>Moln&#225;r, V., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+prognostic+role+of+ultrasound+and+magnetic+resonance+imaging+in+obstructive+sleep+apnoea+based+on+lateral+oropharyngeal+wall+obstruction.">The prognostic role of ultrasound and magnetic resonance imaging in obstructive sleep apnoea based on lateral oropharyngeal wall obstruction.</a> Sleep Breath. , (2022).</li></ol>

None of the authors have any conflicts of interest to disclose.

In 2018, a call to action was made by the leadership of the Society of Cardiovascular Anesthesiologists for "Perioperative ultrasound training in anesthesiology"23. Notably, these leaders highlighted that POCUS education should become an essential component of anesthesiology training programs. More recently, experts in anesthesiology further explained the utility and necessity of POCUS in all aspects of perioperative patient care, including airway management24. Experts emph...

Portable ultrasonography has evident utility in the perioperative care of patients. Its accessibility and lack of invasiveness are benefits that have led to the rapid incorporation of point of care ultrasound (POCUS) to the clinical care of surgical patients1,2. As POCUS continues to find new indications in the perioperative arena, there are several established indications that have clear benefits over traditional clinical exams. In this methods paper, we review the recent findings and demonstrate how to integrate POCUS into clinical practice or airway management.
Undetected esophageal intubation results in significant morbidity and mortality; therefore, it is critical to identify esophageal intubation immediately and place the tube in an endotracheal location to avoid disastrous respiratory compromise. Traditional confirmation of endotracheal intubation relies on clinical examinations such as auscultation for bilateral breath sounds and chest rise3,4. Even after the American Society of Anesthesiologists (ASA) instituted end-tidal CO2 as a required monitor for identifying endotracheal intubation, there still remained cases of undetected esophageal intubation leading to significant morbidity and mortality5. One main benefit of incorporating tracheal ultrasonography into the intubation procedure is that esophageal intubation can be recognized immediately, and real-time, direct visualization of the tube can be confirmed in the trachea. In a recent meta-analysis, the pooled sensitivity and specificity of endotracheal confirmation were 98% and 94%, respectively, illustrating the superior diagnostic accuracy of this technique6. In this methods paper, a video example will be shown of the tube being placed in the esophagus erroneously, immediate recognition of this complication, and proper placement of the tube in the trachea. This highlights the real-time visual benefits that POCUS allows during an intubation procedure.
Despite advances in supraglottic airways and video laryngoscopy, surgical airway may remain a life-saving necessity in a &#34;cannot intubate, cannot oxygenate&#34; scenario. The updated ASA Difficult Airway Guidelines highlight that in the event of a life-saving invasive airway being required, the procedure must be performed as quickly as possible and by a trained specialist7. In the event a cricothyrotomy is required, the identification of proper anatomy is required to prevent further complications. Utilization of ultrasonography to visualize the anatomy of the cricothyroid membrane (CTM) is a quick and effective technique that is now being suggested preoperatively if there is any concern of a difficult airway8. This technique can be taught in a relatively quick manner, with learners gaining almost complete competency after a brief 2 hour tutorial and 20 expert guided scans9. In this methods paper, two techniques to identify the CTM with POCUS will be demonstrated in the hopes of further educating any healthcare providers who routinely perform airway management.
Preoperative assessment of the patient&#39;s airway involves traditional bedside clinical exams (e.g., Mallampati score, mouth opening, cervical range of motion, etc.). There are several problems with these assessments. The first and probably most salient is that they are not very accurate at predicting a difficult airway situation10. In addition, these tests require patient participation, which is not possible in all clinical scenarios (such as in cases of trauma or altered mental status).
Preoperative airway ultrasound measurements have shown improved accuracy in predicting difficult endotracheal tube placement11,12. Anterior neck soft tissue thickness at varying levels has been measured and analyzed as a prediction of difficult intubation. The ultrasonographic measurement of the distance between the skin to epiglottis appears to have the best diagnostic accuracy identified to date13. This measurement has also been shown to improve predictive capability considerably when added to the traditional bedside examinations14. This paper explains how to use POCUS to measure the skin-to-epiglottis distance and incorporate it into the preoperative airway examination, in order to help healthcare providers better predict a difficult airway situation.
In addition, investigators have begun to identify anatomical structures that indicate difficult mask ventilation. One such anatomical structure is the lateral pharyngeal wall, whose thickness (LPWT) has been shown to correspond to the severity of obstructive sleep apnea (OSA) and apnea-hypopnea index15. Preliminary data also suggest that measurement of the LPWT preoperatively provides evidence for the difficulty of mask ventilation16. This methods paper and the associated video will demonstrate how to acquire the LPWT with portable ultrasonography to assess the severity of OSA in a patient and potential for difficulty in mask ventilation.

<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>

image acquisition using portable sonography for emergency airway management

With its increasing popularity and accessibility, portable ultrasonography has been rapidly adapted not only to improve the perioperative care of patients, but also to address the potential benefits of employing ultrasound in airway management. The benefits of point of care ultrasound (POCUS) include its portability, the speed at which it can be utilized, and its lack of invasiveness or exposure of the patient to radiation of other imaging modalities.
Two primary indications for airway POCUS include confirmation of endotracheal intubation and identification of the cricothyroid membrane in the event a surgical airway is required. In this article, the technique of using ultrasound to confirm endotracheal intubation and the relevant anatomy is described, along with the associated ultrasonographic images. In addition, identification of the anatomy of the cricothyroid membrane and the ultrasonographic acquisition of appropriate images to perform this procedure are reviewed.
Future advances include utilizing airway POCUS to identify patient characteristics that might indicate difficult airway management. Traditional bedside clinical exams have, at best, fair predictive values. The addition of ultrasonographic airway assessment has the potential to improve this predictive accuracy. This article describes the use of POCUS for airway management, and initial evidence suggests that this has improved the diagnostic accuracy of predicting a difficult airway. Given that one of the limitations of airway POCUS is that it requires a skilled sonographer, and image analysis can be operator dependent, this paper will provide recommendations to standardize the technical aspects of airway ultrasonography and promote further research utilizing sonography in airway management. The goal of this protocol is to educate researchers and medical health professionals and to advance the research in the field of airway POCUS.

By utilizing real-time ultrasound probe visualization of the trachea, the directions in step 1 of the protocol enable the airway manager to secure the airway expeditiously and safely. The endotracheal tube is quickly recognized and removed from the esophagus by following the steps for placement in the proper endotracheal position under ultrasound visualization (Figure 1, Figure 2, and Figure 3). The advantage of thi...

Watch this Scientific Journal Video about Image Acquisition using Portable Sonography for Emergency Airway Management at JoVE.com

Image Acquisition using Portable Sonography for Emergency Airway Management

Point of care ultrasound (POCUS) is increasingly being utilized in airway management. Presented here are some clinical utilities of POCUS, including differentiating endotracheal and esophageal intubation, identification of the cricothyroid membrane in the event a surgical airway is required, and measuring anterior neck soft tissue to predict difficult airway management.

With its increasing popularity and accessibility, portable ultrasonography has been rapidly adapted not only to improve the perioperative care of ...

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2.1K Views.  George Washington University School of Medicine and Health Sciences. Point of care ultrasound (POCUS) is increasingly being utilized in airway management. Presented here are some clinical utilities of POCUS, including differentiating endotracheal and esophageal intubation, identification of the cricothyroid membrane in the event a surgical airway is required, and measuring anterior neck soft tissue to predict difficult airway management. 

Video: Image Acquisition using Portable Sonography for Emergency Airway Management

Esophageal Heat Transfer for Patient Temperature Control and Targeted Temperature Management

Controlling patient temperature is important for a wide variety of clinical conditions. Cooling to normal or below normal body temperature is often performed for neuroprotection after ischemic insult (e.g. hemorrhagic stroke, subarachnoid hemorrhage, cardiac arrest, or other hypoxic injury). Cooling from febrile states treats fever and reduces the negative effects of hyperthermia on injured neurons. Patients are warmed in the operating room to prevent inadvertent perioperative hypothermia, which is known to cause increased blood loss, wound infections, and myocardial injury, while also prolonging recovery time. There are many reported approaches for temperature management, including improvised methods that repurpose standard supplies (e.g., ice, chilled saline, fans, blankets) but more sophisticated technologies designed for temperature management are typically more successful in delivering an optimized protocol. Over the last decade, advanced technologies have developed around two heat transfer methods: surface devices (water blankets, forced-air warmers) or intravascular devices (sterile catheters requiring vascular placement). Recently, a novel device became available that is placed in the esophagus, analogous to a standard orogastric tube, that provides efficient heat transfer through the patient&#39;s core. The device connects to existing heat exchange units to allow automatic patient temperature management via a servo mechanism, using patient temperature from standard temperature sensors (rectal, Foley, or other core temperature sensors) as the input variable. This approach eliminates vascular placement complications (deep venous thrombosis, central line associated bloodstream infection), reduces obstruction to patient access, and causes less shivering when compared to surface approaches. Published data have also shown a high degree of accuracy and maintenance of target temperature using the esophageal approach to temperature management. Therefore, the purpose of this method is to provide a low-risk alternative method for controlling patient temperature in critical care settings.

This study presents a novel method to provide efficient patient temperature control for cooling or warming patients. A single use, triple lumen device is placed into the esophagus, analogous to a standard orogastric tube, and connects to existing heat exchange units to perform automatic patient temperature management.

Controlling patient temperature is important for a wide variety of clinical conditions. Cooling to normal or below normal body temperature is often ...

Endotracheal Intubation Using a Flexible Intubation Endoscope as a Standardized Model for Safe Airway Management in Swine

Endotracheal intubation is often a basic requirement for translational research in porcine models for various interventions that require a secured airway or high ventilation pressures. Endotracheal intubation is a challenging skill,&#160;requiring a minimum number of successful endotracheal intubations to achieve a high success rate under optimal conditions, which is often unachievable for non-anaesthesiology researchers. Due to the specific porcine airway anatomy, a difficult airway can usually be assumed. The impossibility of establishing a secure airway can result in injury, adverse events, or death of the laboratory animal. Using a prospective, randomized, controlled evaluation approach, it has been shown that fiberoptic-assisted endotracheal intubation takes longer but has a higher first-pass success rate than conventional intubation without causing clinically relevant drops in oxygen saturation. This model presents a standardized regimen for endoscopically guided endotracheal intubation, providing a secured airway, especially for researchers who are inexperienced in the technique of endotracheal intubation via direct laryngoscopy. This procedure is expected to minimize animal suffering and unnecessary animal losses.

The use of pigs in research has increased in recent years. Nevertheless, pigs are characterized by difficult airway anatomy. By demonstrating how to perform endoscopically guided endotracheal intubation, the present protocol aims to further increase laboratory animals' safety to avoid animal suffering and unnecessary death.

Endotracheal intubation is often a basic requirement for translational research in porcine models for various interventions that require a secured airway ...

Image Acquisition Method for the Sonographic Assessment of the Inferior Vena Cava

Over the past several decades, clinicians have incorporated several applications of diagnostic point-of-care ultrasound (POCUS) into medical decision-making. Among the applications of POCUS, imaging the inferior vena cava (IVC) is practiced by a wide variety of specialties, such as nephrology, emergency medicine, internal medicine, critical care, anesthesiology, pulmonology, and cardiology. Although each specialty uses IVC data in slightly different ways, most medical specialties, at minimum, attempt to use IVC data to make predictions about intravascular volume status. While the relationship between IVC sonographic data and intravascular volume status is complex and highly context-dependent, all clinicians should collect the sonographic data in standardized ways to ensure repeatability. This paper describes standardized IVC image acquisition including patient positioning, transducer selection, probe placement, image optimization, and the pitfalls and limitations of IVC sonographic imaging.&#160;This paper also describes the commonly performed anterior IVC long-axis view and three other views of the IVC that can each provide helpful diagnostic information when the anterior long-axis view is difficult to obtain or interpret.

Point-of-care ultrasound evaluation of the inferior vena cava (IVC) is commonly utilized to identify, among other things, the volume status. Imaging should be performed systematically to ensure repeatability. This manuscript reviews the methods and pitfalls of sonographic IVC examination.

Over the past several decades, clinicians have incorporated several applications of diagnostic point-of-care ultrasound (POCUS) into medical ...

Point-Of-Care Ultrasound Screening for Proximal Lower Extremity Deep Venous Thrombosis

Acute lower extremity deep venous thrombosis (DVT) is a serious vascular disorder that requires accurate and early diagnosis to prevent life-threatening sequelae. While whole leg compression ultrasound with color and spectral Doppler is commonly performed in radiology and vascular labs, point-of-care ultrasound (POCUS) is becoming more common in the acute care setting. Providers appropriately trained in focused POCUS can perform a rapid bedside examination with high sensitivity and specificity in critically ill patients. This paper describes a simplified yet validated approach to POCUS by describing a three-zone protocol for lower extremity DVT POCUS image acquisition. The protocol explains the steps in obtaining vascular images at six compression points in the lower extremity. Beginning at the level of the proximal thigh and moving distally to the popliteal space, the protocol guides the user through each of the compression points in a stepwise manner: from the common femoral vein to the femoral and deep femoral vein bifurcation, and, finally, to the popliteal vein. Further, a visual aid is provided that may assist providers during real-time image acquisition. The goal in presenting this protocol is to help make proximal lower extremity DVT exams more accessible and efficient for POCUS users at the patient&#39;s bedside.

Traditionally, lower extremity deep venous thrombosis (DVT) is diagnosed by radiology-performed venous duplex ultrasound. Providers appropriately trained in focused point-of-care ultrasound (POCUS) can perform a rapid bedside examination with high sensitivity and specificity in critically ill patients. We describe the scanning technique for focused POCUS DVT lower extremity examination.

Acute lower extremity deep venous thrombosis (DVT) is a serious vascular disorder that requires accurate and early diagnosis to prevent life-threatening ...

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.

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

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.

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

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.

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 ...

Focused Assessment with Sonography for Trauma (FAST) Exam: Image Acquisition

Over the past twenty years, the Focused Assessment with Sonography for Trauma (FAST) exam has transformed the care of patients presenting with a combination of trauma (blunt or penetrating) and hypotension. In these hemodynamically unstable trauma patients, the FAST exam permits rapid and noninvasive screening for free pericardial or peritoneal fluid, the latter of which implicates intra-abdominal injury as a likely contributor to the hypotension and justifies emergent abdominal surgical exploration. Further, the abdominal portion of the FAST exam can also be used outside of the trauma setting to screen for free peritoneal fluid in patients who become hemodynamically unstable in any context, including after procedures that may inadvertently injure abdominal organs. These "non-trauma" situations of hemodynamic instability are often triaged by providers from specialties other than emergency medicine or trauma surgery who are not familiar with the FAST exam. Therefore, there is a need to promulgate knowledge about the FAST exam to all clinicians caring for critically ill patients. Toward this end, this article describes FAST exam image acquisition: patient positioning, transducer selection, image optimization, and exam limitations. Since the free fluid is likely to be found in specific anatomic locations that are unique for each canonical FAST exam view, this work centers on the unique image acquisition considerations for each window: subcostal, right upper quadrant, left upper quadrant, and pelvis.

Focused Assessment with Sonography for Trauma FAST Exam: Image Acquisition

The Focused Assessment with Sonography for Trauma (FAST) exam is a diagnostic point-of-care ultrasound examination used to screen for the presence of free fluid in the pericardium and peritoneum. Indications, techniques, and pitfalls of the procedure are discussed in this article.

Over the past twenty years, the Focused Assessment with Sonography for Trauma (FAST) exam has transformed the care of patients presenting with a ...

Gastric Ultrasound Technique for Mitigating Peri-Procedural Aspiration Risk

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

Over the past two decades, diagnostic point-of-care ultrasound (POCUS) has emerged as a rapid and non-invasive bedside tool for addressing clinical inquiries related to gastric content. One emerging concern pertains to patients about to undergo sedation and/or endotracheal intubation: the elevated risk of aspiration from the patient&#39;s stomach contents. Aspiration of gastric contents into the lungs poses a serious and potentially life-threatening complication. This occurs more frequently when the stomach is considered &#34;full&#34; and can be affected by the techniques employed for airway management, making it potentially preventable. To mitigate the risk of peri-procedural aspiration, two distinct medical specialties (anesthesiology and critical care medicine) have independently developed techniques to utilize ultrasonography for identifying patients requiring &#34;full stomach&#34; precautions. Due to these separate specialties, the work of each group remains relatively unfamiliar outside its respective field. This article presents descriptions of both techniques for gastric ultrasound. Furthermore, it explains how these approaches can complement each other when one of them falls short. Regarding image acquisition, the article covers the following topics: indications and contraindications, selection of the appropriate probe, patient positioning, and troubleshooting. The article also delves into image interpretation, complete with example images. Additionally, it demonstrates how one of the two techniques can be employed to estimate gastric fluid volume. Lastly, the article briefly discusses medical decision-making based on the findings of this examination.

Author Spotlight: Point-of-Care Ultrasound for Gastric Content Assessment and Risk Stratification in Perioperative Care 

This protocol introduces two methods for image acquisition in gastric ultrasonography. Additionally, tips are provided for interpreting this information to assist in medical decision-making.

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

Quantitative Autofluorescence (QAF) Image Acquisition

To begin, get the participant seated comfortably in front of the quantitative autofluorescence, or qAF device to ensure accurate image acquisition. Have the participant's chin and forehead pressed against the chin and headrest. Adjust the height of the chin rest until the lateral eyelid angle is at the same height as the red marking.Then rotate the wheel on the recording device until the small vessels are in focus to ensure the image is focused in the near infrared modus. Zoom in on the eye by moving the camera forward until the image corners are evenly illuminated. As a rule of thumb, adjust the focus to the spherical equivalent.Reduce the focus before qAF imaging by one or two diopters as blue QAF uses a shorter wavelength, and switch to the modus of the qAF device from the near infrared to the qAF mode. Readjust and upscale the illumination and fine-tune the focus of the image until the small vessels closest to the fovea are in focus and the image is brightly illuminated without red dots. To bleach the photoreceptor pigment in the field of view of the camera, wait for at least 30 seconds in the qAF mode before image acquisition.To capture images, press Image Acquisition on the touchpad of the imaging device. Capture more than one qAF image in case of blinking or sudden eye movements during acquisition.