Dr. Chew Kiat Yeoh
EMSJ DalEM PoCUS Fellow
Privacy note: This is case is imaginary and includes components from various cases seen by the author over the last 5 years. It is presented in this way for educational purposes.
EMSJ DalEM PoCUS Fellow
Privacy note: This is case is imaginary and includes components from various cases seen by the author over the last 5 years. It is presented in this way for educational purposes.
PoCUS Clinical Pearl by Dr. Chew Kiat Yeoh
DalEM PoCUS Fellow
Reviewed by: Dr. David Lewis
Dr. Kavish Chandra MD, CCFP (EM)
PoCUS Clinical Pearl by Dr. Rawan Makhdom
DalEM PoCUS Fellow
Reviewed by Dr. D Lewis
Copy Edited by Dr. D Lewis
Pdf Download: EMSJ RMakhdom Ultrasound in Tonsillitis – Submandibular Approach
A 33-year-old gentleman presents to the ED with a history of fever and sore throat for the past week.
Seven days ago, he was diagnosed with tonsillitis and started on Amoxicillin but showed no clinical improvement.
Three days ago, his antibiotic was changed to Azithromycin.
At his present visit, he is febrile with a complaint of sore throat and muffled voice.
Tonsillitis is an infection or inflammation of the tonsils. The tonsils are areas of lymph tissue on both sides of the throat, above and behind the tongue. They are part of the immune system, which helps the body fight infection. Tonsillitis is usually self-limiting, with most patients recovering within 4 to 10 days. Tonsillitis is usually viral, but can be bacterial e.g., strep throat and in rare cases, a fungus or a parasite can cause tonsillitis. The main symptoms of tonsillitis are a sore throat, and swollen tonsils. Symptoms may also include a fever, a congested or runny nose, swollen lymph nodes, a headache, and trouble swallowing.
Figure 1: Normal vs Inflamed Tonsils. (Mayoclinichealthsystem.org)
Figure 2: Ultrasound of Normal Tonsil using Endocavity Approach. (Google images)
Technique:
Advantages:
Disadvantages:
Technique:
Figure 3: Submandibular Approach for Scanning Tonsils using High Frequency Probe. (Brown Emergency Medicine brownemblog.com)
Comparing the two different techniques, intraoral had a sensitivity and specificity of 91% and 75% while transcervical (TCU) had a sensitivity and specificity of 80% and 81% (4).
Figure 4: Ultrasound of PTA using Linear Probe. (SJRHEM)
Figure 5: Ultrasound of PTA using Curvilinear Probe. (SJRHEM)
Figure 6: Another Ultrasound of PTA using Linear Probe. (SJRHEM)
PoCUS Clinical Pearl
Dr Steven Chen
DalEM PoCUS Elective
PGY2 Internal Medicine, University of Toronto
Reviewed: Dr David Lewis
Copyedited: Dr David Lewis
The pursuit of a rapid and objective measure of volume status has always been a vexing problem for clinicians as proper fluid management is pivotal for patient outcomes. In recent years, there has been increased attention towards the concept of “fluid-responsive” as liberal fluid boluses can often be associated with poor outcomes as a result of systemic congestion. 1
In the POCUS community, while Inferior Vena Cava (IVC) measurements have promise in assessing central venous pressure, the subsequent translation towards “volume responsiveness” has been met with many other limitations. For one, it did not account for venous congestion at other organ levels such as the pulmonary, renal, or hepatic systems. 2,3
Venous excess ultrasound (VExUS) is a growing bedside ultrasound-based approach that aims to provide a more comprehensive assessment of venous congestion. This was initially described by Beaubien-Souligny et al. (2020) from a post-hoc analysis correlating ultrasound grading parameters with risk in development of AKI in cardiac surgery patients.4 The protocol serves to assess multiple sites of venous congestion, including the IVC, hepatic veins, portal veins and intrarenal veins. By assessing congestion in these multiple sites, the VExUS score has gained attraction in providing a more comprehensive assessment of systemic congestion. 4,5
The VExUS protocol is composed of four main components outlined below:
This can be performed using either the curvilinear probe (preferred) or the phased array probe. The patient should be positioned flat and supine on the bed to acquire the views. The table below depicts some suggested views where larger regions of the veins may be accessible for pulse wave doppler gating in reference to standardized sonography protocols. 6,7
Note: Reviewing the basics of pulse wave doppler will be needed prior to completing VExUS scans (not covered in this article).
Interpretation of the VExUS grading system is well summarized in diagram below (sourced from POCUS1018) and takes some practice to differentiate normal from abnormal waveforms. Pulse wave doppler assessment is pursued only if the inferior vena cava is found plethoric, defined as greater or equal to 2cm. 4,5
Each of the hepatic, portal and renal veins are subsequently examined and classified as normal, mildly congested, or severely congested. The VExUS system has four grades: Grade 0 represents no congestion in any organ, Grade 1 represents only mild congestive findings, Grade 2 represents severe congestive findings in only one organ, and Grade 3 represents severe congestive findings in at least two out of three organ systems. 4,5
Source: POCUS1018
Some sample waveforms are shown below with comments to help with distinguishing normal from abnormal waveforms.
VExUS has also been shown to be reliable and reproducible, with good interobserver agreement in trained individuals and correlation with other measures of volume status such as central venous pressure.4,5 As the technique is growing in the POCUS literature, below is a table summarizing several recent studies exploring its application across numerous settings.
Study | Purpose | Results |
Beaubien-Souligny W, et al. (2020)4
Post-hoc analysis of a single centre prospective study in 145 patients
|
Initial model of VExUS grading system looking at association in development of AKI in cardiac surgery population | Association with subsequent AKI:
HR: 3.69 CI 1.65–8.24 p = 0.001; +LR: 6.37 CI 2.19–18.50 when detected at ICU admission, which outperformed central venous pressure measurements
|
Bhardwaj V, et al. (2020)9
Prospective cohort study of 30 patients in ICU setting
|
Prospective study on application of VExUS scoring on staging of AKI in patients with cardiorenal syndrome | Resolution of AKI injury significantly correlated with improvement in VExUS grade (p 0.003).
There was significant association between changes in VExUS grade and fluid balance (p value 0.006). |
Varudo R, et al. (2022)10
Case report of ICU patient with hyponatremia |
Application of VExUS in case report as rapid tool to help with volume status assessment in patient with complex hyponatremia | Overall VExUS grade 2, prompting strategy for diuresis with improvement |
Rolston D, et al. (2022)11
Observational study of 150 septic patients in single centre |
VExUS score performed on ED septic patients prior to receiving fluids with chart review done to determine if there is association with poorer outcomes | Composite outcome (mortality, ICU admission or rapid response activation):
VExUS score of 0: 31.6% of patients VExUS score of 1: 47.6% of patients VExUS score >1: 67.7% of patients (p: 0.0015) |
Guinot, PG, et al. (2022)12
Prospective observational study of 81 ICU patients started on loop diuretic therapy |
Evaluation of multiple scores to predict appropriate diuretic-induced fluid depletion (portal pulsatility index, renal venous impedance index, VExUS) | Baseline portal pulsatility index and renal venous impedance index were found to be superior predictors compared to VExUS.
The baseline VExUS score (AUC of 0.66 CI95% 0.53–0.79, p = 0.012) was poorly predictive of appropriate response to diuretic-induced fluid depletion. |
Menéndez‐Suso JJ, et al. (2023)13
Cross-sectional pilot study of 33 children in pediatric ICU setting |
Association of VExUS score with CVP in pediatric ICU | VExUS score severity was strongly associated with CVP (p<0.001) in critically ill children. |
Longino A, et al. (2023)14
Prospective validation study in 56 critically ill patients |
Validation looking at association of VExUS grade with right atrial pressure. | VExUS had a favorable AUC for prediction of a RAP ≥ 12 mmHg (0.99, 95% CI 0.96-1) compared to IVC
diameter (0.79, 95% CI 0.65–0.92). |
It should be kept in mind that numerous factors may affect interpretation of VExUS gradings.
For the IVC component, increased intra-abdominal pressure can affect measurements independently of the pressure in the right atrium or may be affected by chronic pulmonary hypertension. The hepatic vein may not show significant changes even in severe tricuspid regurgitation if the right atrium can still expand and contract normally. In thin healthy people and those with arteriovenous malformations, the portal vein can have a pulsatile flow without venous congestion. It is also important to note that for patients with underlying disease renal or liver parenchymal disease, venous doppler recordings may be less reliable. 3-5
Outside of physiologic factors, another limitation is the need for adequate training and familiarity in performing and interpreting the technique. While VExUS is fairly well protocolized, it requires proficiency with pulse wave doppler to perform accurately. As with any new technique, there is a risk of variability in technique and interpretation. To avoid misinterpretation, it is important to consider repeat tracings to ensure consistency of results and to consider findings within the overall clinical context of the patient.
VExUS is a non-invasive ultrasound method for assessing venous congestion across multiple organ systems. While there are several physiologic limitations and results need to be used in adjunct with the clinical picture, studies have shown promise for VExUS to be incorporated as part of a physician’s toolkit to help with clinical decision making. 3-5
DalEMSJ PoCUS Fellow
Consultant Emergency Medicine
King Fahad Hospital of the University, Al Khobar KSA
Resuscitative TEE – the whats, the whys and the hows…. A brief review of the literature, examples of use and a proposed cardiac arrest protocol
Professor, Dalhousie Department of Emergency Medicine
Download Slides – PoCUS Rounds – TEE – Nov 2022
http://pie.med.utoronto.ca/tee/
ACEP NOW – How to Perform Resuscitative Transesophageal Echocardiography in the Emergency Department
Dr. Jill Carter Dalhousie EM Resident
Dr. David Lewis
Dr. Rawan AlRashed & Dr. Kyle Traboulsee