PoCUS for Diverticulitis

Dal PoCUS Fellowship – Journal Club – Feb 2021

Dr. Mandy Peach  CCFP-EM

PoCUS Fellow

Dalhousie University Department of Emergency Medicine

 

A Prospective Evaluation of Point-of-Care Ultrasonographic Diagnosis of Diverticulitis in the Emergency Department Allison Cohen, MD*; Timmy Li, PhD; Brendon Stankard, RPA-C; Mathew Nelson

 

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Lisfranc Injury – We have PoCUS but do we still need the cavalry?

 

 

PoCUS Fellow Pearl

Dr. Melanie Leclerc, CCFP-EM

MSK PoCUS Fellow

Dalhousie University Department of Emergency Medicine

 

Reviewed & Edited by Dr David Lewis (@e_med_doc)

All case histories are illustrative and not based on any individual


 

Case Report

A 32 year old male presents to a rural Emergency Department with a complaint of traumatic left foot pain. He was playing recreational football this evening. While crouching, the patient was tackled by another player who landed on his hyper-plantar flexed left foot from behind. The patient had immediate onset of pain in the middle of his foot and was unable to weight-bear. 

On physical examination, you notice significant bruising and swelling of the mid-foot. There is tenderness to the medial mid-foot specifically at the 1st-2nd tarsal-metatarsal articulations. X-rays of the foot appear normal. You are concerned about the possibility of a ligamentous Lisfranc injury.

https://www.footandanklesurgery.com.au/lisfranc-injuries

 


 

Lisfranc injuries

Lisfranc injuries are those that involve the tarsal-metatarsal joints. A spectrum of injury exists from ligamentous to fracture-dislocation. Up to 20% – 40% of injuries to the Lisfranc complex are missed in the Emergency Department. Unrecognized and untreated injuries can lead to long-term instability through the midfoot. As this region of the foot is responsible for a significant load during weight bearing, instability can accelerate degenerative changes in the foot resulting in chronic pain and disability

The injury is named after Jacques Lisfranc de St. Martin, a French surgeon and gynecologist performed forefoot amputations at the tarsometatarsal joint on cavalrymen, during the 1815 Napoleonic wars. Although he didn’t specifically describe the injury, it has since been recognised in equestrians and occurring as a result of a trapped plantar flexed foot in the stirrup during a fall.

 

Other mechanisms have been described including high velocity injuries (sports injuries, foot on brake pedal MVA) and low velocity injuries (Stepping off a curb awkwardly). Low velocity injuries are more likely to be missed than high velocity injuries.

Further Reading – OrthoBullets


 

Anatomy

The Lisfranc ligament complex is comprised of 3 ligaments. The dorsal (red), interosseous (blue) and the plantar (green) Lisfranc ligaments. The  Interosseous ligament is the largest and the dorsal ligament is the smallest.

The first and second rays have unique ligamentous anatomy wherein no intermetatarsal ligaments exist, but extreme strength is imparted by dorsal, interosseous, and plantar bundles of ligament binding the lateral aspect of the medial cuneiform bone with the medial head of the second metatarsal bone—the Lisfranc ligamentous complex. Only the dorsal and plantar Lisfranc ligaments are accessible to ultrasound.

 

 



 

PoCUS of the Lisfranc joint and dorsal lisfranc ligament (DLL)

Lisfranc injuries are one of the most commonly missed orthopaedic injuries in the Emergency Department. Normal X-rays are often falsely reassuring to providers and patients are discharged with a diagnosis of “soft-tissue injury”. These injuries result in midfoot instability and often require definitive surgical management.

PoCUS has been studied as a method of early detection of these injuries. Specifically, assessment of the dorsal lisfranc ligament (DLL) between the second metatarsal (M2) and the medial cuneiform(C1). PoCUS also has the advantages of being significantly cheaper and more accessible than CT and MRI. Further investigation is needed to validate this method of diagnosis, however ultrasound findings of a disrupted DLL and a widened C1-M2 interval compared to the contralateral side may increase your suspicion when pre-test probability is high.


 

Technique

  1. Linear probe-MSK setting starting at a depth of 2cm
  2. Place probe in transverse orientation over the proximal aspect of the 1st-2nd metatarsals with the probe indicator to the patient’s right
  3. Slide the transducer proximally until you locate the medial cuneiform and identify the junction between the medial cuneiform (C1) and the 2nd metatarsal (M2)
  4. The medial cuneiform will have an angulated contour appearance in contrast to the round appearance of the metatarsals
  5. Sweep to identify the dorsal lisfranc ligament (DLL)
  6. Assess the DLL for a fibrillar pattern, normal echogenicity and contour
  7. Measure the DLL width and the C1-M2 distance compare to the contralateral side
  8. Measure the C1-M2 distance with weightbearing (if patient tolerates) to compare
  9. Apply colour doppler to assess for hyperemia


 

PoCUS Findings

Medial Cuneiform (C1), 2nd Metatarsal (M2)

Note the angulated contour of C1 and the smooth contour of M2 – this sectional plane is important when locating the dorsal Lisfranc ligament. The ligament appears hypoechoic with a fibrillar pattern, typical for other ligaments more commonly visualized with PoCUS e.g MCL, ATFL.

1. Normal image – Arrows = dorsal Lisfranc ligament

2. Normal Clip and annotated image. Note how the dorsalis pedis a. frequently overlies the dorsal Lisfranc ligament (yellow lines)

3. Normal clip. Note how there is no separation of C1/M2 while counterstressing the 1st and 2nd rays


 

4. Thickened, convex contour

5. DLL disrupted, wide joint space

6. Widening C1-M2 with weightbearing


Video Case


 

Limitations

  1. Anisotropy – Irregular dorsal contour of foot can result in difficult perpendicular imaging of doral Lisfranc ligament. Stand-off gel pad may help.
  2. History of prior trauma – chronic Lisfranc injury may result in joint widening
  3. Bilateral injuries – inability to compare sides to judge joint space widening

Application

Standard foot radiographs should be performed in all cases of suspicion for Lisfranc Injury. Weight bearing radiographs should also be performed if tolerated (the ability to fully weight bear is often limited in the acute setting)

HIgh velocity injuries result in significant soft tissue swelling, and although non-weight bearing radiographs may not be diagnostic, the index of suspicion for Lisfranc injury will be high. Immobilization +/- early CT and follow up with foot and ankle specialist is recommended. For these, high pretest probability injuries, PoCUS findings are unlikely to change management significantly. A clear Lisfranc ligament rupture on PoCUS may trigger a request for CT/MRI earlier than otherwise considered. In most cases advanced imaging and a clear diagnosis is not usually possible until the swelling has subsided.

In low velocity injuries, soft tissue swelling is less pronounced. in the acute presentation the ability to perform weight bearing radiographs is limited by pain. Index of suspicion for Lisfranc injury may be low-moderate and the decision to immobilize and refer for specialist follow up can be difficult. While there is limited published evidence for PoCUS test characteristics in Lisfranc injury, a positive scan (injury + disrupted ligament / widening of C1/M2) is likely to be highly specific. Patients with positive PoCUS findings should therefore be immobilized and referred for specialist follow up. In those with negative or inconclusive findings, management and disposition will depend on degree of clinical suspicion and correlated with radiographic findings.

In summary, PoCUS provides a useful additional piece of information that can be plugged into a bayesian diagnostic pathway. What is the pretest probability of a particular diagnosis? After reviewing radiographs and performing PoCUS is the diagnosis more or less likely?

More evidence is required to fully understand the test characteristics of PoCUS for Lisfranc injury. Would the addition of plantar views improve sensitivity?

Although the performing the scan takes only a few minutes, it is quite technically challenging for the novice. As with all MSK PoCUS, repeated practice in numerous patient presentations will increase operator speed and accuracy.


 

Finally, although we still need the cavalry, PoCUS can help us decide which regiment and how quickly we need them!

 


References

  1. Mayich DJ, Mayich MS, Daniels TR. Effective detection and management of low-velocity Lisfranc injuries in the emergency setting: principles for a subtle and commonly missed entity. Can Fam Physician. 2012;58(11):1199-e625. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3498011
  2. Woodward, S., Jacobson, J.A., Femino, J.E., Morag, Y., Fessell, D.P. and Dong, Q. (2009), Sonographic Evaluation of Lisfranc Ligament Injuries. Journal of Ultrasound in Medicine, 28: 351-357.
  3. Döring, S., Provyn, S., Marcelis, S., Shahabpour, M., Boulet, C., de Mey, J., De Smet, A., De Maeseneer, M. (2018). Ankle and midfoot ligaments: Ultrasound with anatomical correlation: A review. Eur J Radiol.107:216-226.
  4. Kaicker, J., Zajac, M., Shergill, R., & Choudur, H. N. (2016). Ultrasound appearance of the normal Lisfranc ligament. Emergency Radiology, 23(6), 609-614.
  5. DeLuca, M.K., Walrod, B. and Boucher, L.C. (2020). Ultrasound as a Diagnostic Tool in the Assessment of Lisfranc Joint Injuries. J Ultrasound Med, 39: 579-587.
  6. Marshall, J., Graves, N.C., Rettedal, D.D., Frush, K., Vardaxis. V. (2013). Ultrasound Assessment of Bilateral Symmetry in Dorsal Lisfranc Ligament. The Journal of Foot and Ankle Surgery, 52(3): 319-323.
  7. Rettedal, D.D., Graves, N.C., Marshall, J.J. et al. Reliability of ultrasound imaging in the assessment of the dorsal Lisfranc ligament. J Foot Ankle Res 6, 7 (2013).
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Skin and Soft Tissue Infections: A PoCUS Guided Approach

Medical Student Clinical Pearl – November 2020

 

Robert Hanlon

@roberthanlon12

Year: 4
DMNB Class of 2021
 

Reviewed and Edited by Dr. David Lewis

All case histories are illustrative and not based on any individual

 


Case Report

A 25yr old male presents with a 3 day history of a red swollen foot following an insect bite. He has no past medical history. On examination there is some erythema and swelling on the dorsum of the left foot. Palpation is very tender.

You are aware of recommended guidelines that advise I&D for purulent infections and decide to proceed with the procedure. Despite trying to freeze the area with lidocaine, the procedure is still painful and no pus is drained. You point to the minimal serosanguinous exudate and sheepishly suggest to the patient that the I&D was successful and that a course of antibiotics will resolve this issue.


Skin and Soft Tissue Infections: A POCUS Guided Approach

Skin and soft tissue infections (SSTIs) have a variety of potential causes, ranging in severity from mild infections like cellulitis to abscess all the way to life-threatening causes like necrotizing fasciitis.1 SSTIs are commonly encountered in the emergency department, with cellulitis and abscesses being the two most common.2 It is important to be able to recognize SSTIs and provide appropriate treatment. Abscesses require invasive management, whereas cellulitis is treated with systemic therapies; therefore, it is important to be able distinguish the different between the two types. Doing so can be difficult because of the hidden nature of abscesses. However, ultrasound can be a useful tool in establishing the presence of an abscess. This article is a review of the clinical approach and treatment for SSTIs, focusing on cellulitis and abscesses, as well as the use of ultrasound in helping to establish the diagnosis.


Approach

Clinical suspicion is the initial step in the diagnosis of SSTIs. These infections have multiple causes; therefore, obtaining a detailed history is crucial. Information about immunocompromised state, place of residence, travel, any recent trauma or surgery, previous antimicrobial use, lifestyle, hobbies, and animal bites is essential to developing an adequate differential diagnosis.3

A good understanding of the normal skin flora and common infectious organisms is key to assessing SSTIs. The most commons organisms implicated in SSTIs are Staphylococcus aureus and Streptococcus species.4-6 Methicillin resistant S. aureus (MRSA) being an important strain that has increased in prevalence in the past 20 years. Risk factors such as presence of abscess, intravenous drug use, previous MRSA status, antibiotics within 8 weeks, diabetes mellitus, and previous hospital admission within the last year increase the likelihood of the infection being cause by MRSA.4-6

Physical examination findings are crucial for establishing the presence of an SSTI; the typical criteria are a superficial lesion with the classic inflammatory findings of redness (rubor), swelling (tumor), warmth (calor), and pain (dolor).1,2,7 An abscess is defined as a fluctuant mass of puss localized and buried within a tissue, organ, or potential space; however, clinically it can be hard to determine to presence of this mass.2,7 Other associated signs and symptoms, such as crepitus, bullae, and hemorrhage, may be present upon diagnosis or may develop later during the course.2,7 Due to overlapping clinical presentations of the different SSTIs, it can be difficult to differentiate between them.


Cellulitis – No Abscess
Cellulitis – Possible Abscess
Abscess
Early Abscess

Assessment with POCUS:

Due to the similarities between different SSTI cutaneous findings and their different treatments, it is important to establish if there is an abscess present. It was common, before the introduction of ultrasound, to perform a blind needle aspiration of the infected area in order to determine the presence/absence of an abscess.8,9 However, this subjects that patient to the risks of an invasive procedure as well as pain. On the other hand, treating infection with empiric antibiotics in the presence of an unknown abscess delays drainage and allows for potential worsening of the infection.8,9

A study by Tayal et al. demonstrated that the use of ultrasound was beneficial in patients who had both low and high pretest probability for needing incision and drainage. In patients suspected of having simple cellulitis (low pretest), ultrasound was used to change management in over half of participants; establishing the need for drainage due to imaging of a fluid collection. The opposite was true in the patients suspected of having an abscess (high pretest); the study found that ultrasound was able to determine that more than half of this group did not need drainage, because of the absence of a fluid collection on imaging.10 Other studies have had similar findings, but the percent change in management was slightly lower.11

A study by Barbic et al. demonstrated that POCUS provided a rapid, non-invasive, painless, and easily repeatable test, that distinguished between abscess and cellulitis in the vast majority of cases. Their analysis concluded that POCUS had a sensitivity of 96.2% and a specificity of 82.9% in diagnosing the presence of an abscess.12 They concluded that POCUS can accurately diagnose abscess in paediatric and adult populations and is likely superior to clinical examination.12


Cobblestones

Classic finding for cellulitis (but not specific to cellulitis). There will be hyperechoic lobules of subcutaneous fat surrounded by relatively hypoechoic inflammatory fluid.13

Cobblestone – Cellulitis

Purulent Fluid Collection

Classic finding for an abscess; have a rounded shape of anechoic or hypoechoic fluid collection, and there will be surrounding areas of cobblestones from the overlying cellulitis.13 As well, there should be no color flow if doppler is applied to the area (helping to distinguish from lymph node or vessel).14

Abscess – Anechoic Collection
Possible Abscess or Lymph Node? – This is a lymph node – see below
Colour flow differentiates lymph node from abscess

Necrotizing Fasciitis

Because you do not want to miss it! Findings via ‘STAFF’; subcutaneous thickening, air, and fascial fluid.14 Note, that ultrasound does not to exclude the diagnosis. Also need clinical correlation to increase suspicion of such a serious infection.15

Necrotizing Fasciitis – STAFF

Treatment:

According to The Infectious Diseases Society of America (2014) guidelines, management of SSTIs is differentiated based on the presence/absence of purulence (i.e. abscess/fluid collection). They recommend that all purulent infections be treated with incision and drainage, with more severe infections (signs of systemic involvement) being cultured with sensitivities in order to add antibiotics to the treatment.16 Otherwise, non-purulent infections are to be treated with systemic antibiotics; the severity of the infection determining the route and choice of agent.16

Antibiotic therapy, in addition to incision and drainage of a skin abscess, is suggested for patients with any of the following:17

  • Single abscess ≥2 cm or multiple abscesses
  • Large are of surrounding cellulitis
  • Patients with immunosuppression or other comorbidities
  • Signs of systemic involvement (fever > 38°C, hypotension, or tachycardia)
  • Poor clinical response to incision and drainage alone
  • Presence of an indwelling medical device
  • High risk for adverse outcomes with endocarditis (these include a history of infective endocarditis, presence of prosthetic valve or prosthetic perivalvular material, unrepaired congenital heart defect, or valvular dysfunction in a transplanted heart)
  • High risk for transmission of aureus to others (such as in athletes or military personnel)

 

Horizon Health’s local trends recommend the following (see guideline or Spectrum app for full details)

Severity of Infection

 

 

Antibiotic

Mild

Moderate

Severe

Cephalexin 500 – 1000mg PO q6h x 5 days

ceFAZolin 2 g IV q8h x 5 days

ceFAZolin 2 g IV q8h +/- Clindamycin 900 mg IV q8h

If true beta-lactam allergy

Cefuroxime 500 mg PO BID or TID x 5 days

Clindamycin 600-900 mg IV q8h x5 days

 

If MRSA suspected

Septra 800/160 mg or 1600/320 mg PO q12h x 5 days

Vancomycin 25-30 mg/kg IV once then 15mg/kg IV q8 to q12h x 5 days

ADD Vancomycin 25-30 mg/kg IV once then 15mg/kg IV q8 to q12h

 


Some research is suggesting that POCUS can take the assessment of abscesses one step-further and impact management based on the depth and size of the fluid collection seen in imaging. Russell et al. found that abscesses less than 0.4cm below the skin surface could be effectively treated without incision and drainage.18 Another study found that patients, with skin abscesses less than or equal to 5cm in diameter, treatment with oral antibiotics in combination with incision and drainage had improved short-term outcomes compared to those patients treated with the procedure alone.18 While as mentioned above, UpToDate, suggests that antibiotics be used in single abscess greater than 2 cm in size. As well, research has found that ultrasound guided incision and drainage provides lower failure rates (less recurrent infections or multiple incisions) compared to blind incision and drainage. Likely due to better visualization of the abscess and more adequate initial drainage.19


Limitations

There are some limitations to POCUS for SSTIs: ultrasound imaging and interpretation rely on the user’s ability to obtain high-quality images in order to assess whether an abscess is present. It is important for the user to be familiar with different findings on ultrasound to guide appropriate treatment. An abscess may appear hypoechoic, hyperechoic, or anechoic (depending on tissue contents), and usually has posterior acoustic enhancement.19 Determining if it is drainable can be difficult due to this variability in imaging, and it is also quite common for early abscesses to present like cellulitis with erythema, no fluctuance, and an ultrasound that is negative for a fluid collection.20 In cases of a suspected evolving abscess, sometimes referred to as a non-ripe abscess, supportive care, including warm compresses, pain control, and close follow-up, is recommended.20 The practitioner may treat this like cellulitis; however, the patient may return with perceived failure of therapy if discharge advice does not include the possibility of of an abscess forming over time.


Abscess examples from the SJ archives


References

  1. Moffarah AS, Al Mohajer M, Hurwitz BL, Armstrong DG. Skin and Soft Tissue Infections. Microbiol Spectr. 2016 Aug;4(4). doi: 10.1128/microbiolspec.DMIH2-0014-2015.

 

  1. Martinez, N. “Skin and Soft-Tissue Infections: Itʼs More Than Just Skin Deep.” Advanced Emergency Nursing Journal, vol. 42, no. 3, 2020, pp. 196–203.

 

  1. Cieri, B., Conway, E., Sellick, J., & Mergenhagen, K. (2019). Identification of risk factors for failure in patients with skin and soft tissue infections. The American Journal of Emergency Medicine, 37(1), 48-52.

 

  1. Borgundvaag, B., Ng, W., Rowe, B., Katz, K., Farrell, Brian, Guimont, Chantal, . . . Gregson, Dan. (2013). Prevalence of methicillin-resistant Staphylococcus aureus in skin and soft tissue infections in patients presenting to Canadian emergency departments. CJEM, 15(3), 141-160.

 

  1. Esposito, S., De Simone, G., Pan, A., Brambilla, P., Gattuso, G., Mastroianni, C., . . . Savalli, F. (2019). Epidemiology and Microbiology of Skin and Soft Tissue Infections: Preliminary Results of a National Registry. Journal of Chemotherapy (Florence), 31(1), 9-14.

 

  1. Stenstrom, R., Grafstein, E., Romney, M., Fahimi, J., Harris, D., Hunte, G., . . . Christenson, J. (2009). Prevalence of and risk factors for methicillin-resistant Staphylococcus aureus skin and soft tissue infection in a Canadian emergency department. CJEM, 11(5), 430-8.

 

  1. Spelman, D., Baddour, LM. (2020). Cellulitis and skin abscess: Epidemiology, microbiology, clinical manifestations, and diagnosis In: UpToDate, Post TW (Ed), UpToDate, Waltham, MA. Retrieved November 11, 2020. From: https://www.uptodate.com/contents/cellulitis-and-skin-abscess-epidemiology-microbiology-clinical-manifestations-and-diagnosis?search=abscess%20treatment&topicRef=110530&source=see_link#H2443336514

 

  1. Comer, Amanda B. “Point-of-Care Ultrasound for Skin and Soft Tissue Infections.” Advanced Emergency Nursing Journal, vol. 40, no. 4, 2018, pp. 296–303.

 

  1. Gaspari, R., Sanseverino, A., & Gleeson, T. (2019). Abscess Incision and Drainage With or Without Ultrasonography: A Randomized Controlled Trial. Annals of Emergency Medicine, 73(1), 1-7.

 

  1. Tayal, V., Hasan, N., Norton, H., & Tomaszewski, C. (2006). The Effect of Soft‐tissue Ultrasound on the Management of Cellulitis in the Emergency Department. Academic Emergency Medicine, 13(4), 384-388.

 

  1. Alsaawi, A., Alrajhi, K., Alshehri, A., Ababtain, A., & Alsolamy, S. (2017). Ultrasonography for the diagnosis of patients with clinically suspected skin and soft tissue infections: A systematic review of the literature. European Journal of Emergency Medicine, 24(3), 162-169.

 

  1. Barbic, D., Chenkin, J., Cho, D., Jelic, T., & Scheuermeyer, F. (2017). In patients presenting to the emergency department with skin and soft tissue infections what is the diagnostic accuracy of point-of-care ultrasonography for the diagnosis of abscess compared to the current standard of care? A systematic review and meta-analysis. BMJ Open, 7(1), E013688.

 

  1. Atkinson DP, Bowra J, Harris T, Jarman B, Lewis D, editors. Point of Care Ultrasound for Emergency Medicine and Resuscitation. Oxford University Press; 2019. pp. 140, 199-200.

 

  1. Gottlieb, M., Schmitz, G., Grock, A., & Mason, J. (2018). What to Do After You Cut: Recommendations for Abscess Management in the Emergency Setting. Annals of Emergency Medicine, 71(1), 31-33.

 

  1. Castleberg, E., Jenson, N., & Dinh, V. (2014). Diagnosis of necrotizing faciitis with bedside ultrasound: The STAFF Exam. The Western Journal of Emergency Medicine, 15(1), 111-113.

 

  1. Stevens, D., Bisno, A., Chambers, H., Dellinger, E., Goldstein, E., Gorbach, S., . . . Wade, J. (2014). Practice guidelines for the diagnosis and management of skin and soft tissue infections: 2014 update by the infectious diseases society of America. Clinical Infectious Diseases : An Official Publication of the Infectious Diseases Society of America, 59(2), 147-159.

 

  1. Spelman, D., Baddour, LM. (2020). Cellulitis and skin abscess in adults: treatment. In: UpToDate, Post TW (Ed), UpToDate, Waltham, MA. Retrieved November 11, 2020. From: https://www.uptodate.com/contents/cellulitis-and-skin-abscess-in-adults-treatment?search=abscess%20treatment&topicRef=110529&source=see_link

 

  1. Russell, F., Rutz, M., Rood, L., Mcgee, J., & Sarmiento, E. (2020). Abscess Size and Depth on Ultrasound and Association with Treatment Failure without Drainage. The Western Journal of Emergency Medicine, 21(2), 336-342.

 

  1. Gaspari, R., Sanseverino, A., & Gleeson, T. (2019). Abscess Incision and Drainage With or Without Ultrasonography: A Randomized Controlled Trial. Annals of Emergency Medicine, 73(1), 1-7.

 

  1. Thornton J, Hellmich T. Evaluation and Management of Abscesses in the Emergency Department. Emergency Medicine Reports. 2017 May 1;38(10).
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Fascia Iliaca Nerve Block

Hip Broke? Hip Block. Use of the fascia iliaca nerve block for analgesia in hip fractures.

Resident Clinical Pearl (RCP) July 2020

Luke Edgar, BScH MD

PGY1 Family Medicine Integrated Emergency Medicine

Dalhousie Saint John

 

Reviewed by Dr. David Lewis


Background

Hip fractures are a common and painful injury diagnosed and treated in the emergency department, with elderly patients representing the majority of cases. Advanced age, comorbidities, and increased sensitivity to side effects from systemic analgesia all pose challenges to achieving adequate pain control.1,2 Additionally, NSAID use in the elderly is frequently contraindicated due renal, cardiac, and gastrointestinal comorbidities as well as drug interactions. In elderly patients, both undertreated pain and opioid analgesia can precipitate delirium.3

Regional nerve blocks for the indication of hip and femoral neck fractures have been shown to reduce pain and need for IV opiates.1 Contraindications include infection over the injection site, patient refusal, and allergy to local anesthetic. Additionally, patients at risk for compartment syndrome (such as those with a concomitant ipsilateral tibial plateau fracture) should be selected cautiously as they may not reliably have increased pain after block.4

There are three main techniques described for regional nerve blocks to provide analgesia for hip and femoral neck fractures.1

  • Fascia Iliaca Nerve Block: Insert a needle through the fascia lata and fascia iliaca, to infiltrate dilute local anesthetic into the fascial compartment which diffuses to block the femoral, lateral femoral cutaneous, and obturator nerves.
  • Femoral Nerve Block: At the level of the femoral triangle, infiltrate local anesthetic around the femoral nerve.
  • 3-in-1 Femoral Nerve Block: At the level of the femoral triangle, infiltrate local anesthetic around the femoral nerve while applying pressure distal to the injection site, encouraging local anesthetic to track superiorly to block the femoral, lateral femoral cutaneous, and obturator nerves.

Figure 1. Lower limb peripheral nerve sensory distribution.5 Circled in red are the nerves blocked using the fascia iliaca technique. Cutaneous distribution of the obturator nerve is not depicted but consists of a small area on the proximal medial thigh.


Technique

Table 1. Supplies and equipment for performing a fascia iliaca nerve block

Table 2. Steps to complete a fascia iliaca nerve block6

Table 3. One person technique  – Steps to complete a fascia iliaca nerve block


Figure 2. Video demonstrating the sonoanatomy of the right femoral triangle. From lateral to medial, femoral nerve, artery and vein (NAVel), labeled with yellow, red, and blue arrows, respectively.


Figure 3. Sonoanatomy of the right femoral triangle, transverse view for the fascia iliaca nerve block.


Figure 4. Sonoanatomy of the right femoral triangle demonstrating ultrasound-guided needle placement using an in-plane technique. Note two pops should be felt as the needle crossed the two fascial planes.


 

For a visual review of these steps and ultrasonographic landmarks, please see the following videos and webpage by EM Ottawa, 5 Minute Sono, and NYSORA:

EM Ottawa

5 Minute Sono

NYSORA

Ultrasound-Guided Fascia Iliaca Block


 

Complications

Serious complications of this procedure are rare, but present.

  • Local Anesthetic Systemic Toxicity (LAST) as a complication of inadvertent intravenous or intra arterial anesthetic injection.7
    1. Incidence is 8 – 30 in 100,0008
    2. Manifestations typically occur within 20 minutes of injection (although onset can be as late as >1 hr) and are primarily neurologic and cardiovascular in nature. Neurologic effects include perioral numbness, metallic taste, mental status change or anxiety, muscle twitches and visual changes, followed by loss of consciousness and seizure. Cardiovascular effects are hypertension and tachycardia followed by arrhythmias, bradycardia, hypotension and cardiac arrest.
    3. Treatment is with intravenous lipid emulsion therapy (Intralipid 20%) 1.5 mL/kg bolus followed by 0.25 mL/kg/min, Maximum total dose 12 mL/kg. Contact your poison control centre if you suspect LAST.
    4. Prior to performing a fascia iliaca block, confirm availability of intralipid within your department to be used in the event of this rare complication.
  • Femoral Nerve injury secondary to intrafascicular injection
    1. Incidence 2-30/100,0008
    2. Most symptoms of paresthesias, numbness, and weakness resolved after several months in the event of this complication8
  • Other complications include infection, nerve block failure, injury secondary to numbness/weakness of limb, and allergy to the local anesthetic.

 

Take Home Message

Femoral nerve blocks are recommended for hip and femoral fractures to reduce pain and opioid analgesia requirements. Given that poor pain control and opioid analgesia are risk factors for delirium in elderly patients, hip blocks may also reduce rates of delirium (further study required). A fascia iliaca block with 20 cc of 0.5% bupivacaine is a well described technique with very few contraindications. To reduce the risk of complications, these blocks should be completed using sterile technique under ultrasound guidance with the help of an assistant. Hip broke? Hip block.

 


 

References

  • Ritcey B, Pageau P, Woo M, Perry J. Regional Nerve Blocks For Hip and Femoral Neck Fractures in the Emergency Department: A Systematic Review. CJEM 2015;18(1):37-47.
  • Hwang U, Richardson LD, Sonuyi TO, Morrison RS. The effect of emergency department crowding on the management of pain in older adults with hip fractures. J Am Geriatr Soc. 2006;54(2):270-5.
  • Morrison RS, Magaziner J, Gilbert M, et al. Relationship between pain and opioid analgesics on the development of delirium following hip fracture. J Gerontol A Biol Sci Med Sci 2003;58(1):76-81.
  • Erak M, EM Ottawa Grand Rounds. Ah, that feels better! The Use of Nerve Blocks in the ED. 2016. https://emottawablog.com/2016/10/ah-that-feels-better-the-use-of-nerve-blocks-in-the-ed/. Accessed July 25, 2020.
  • Gray H. 1918. Nerve supply of the leg. Anatomy of the Human Body. Image retrieved from https://en.wikipedia.org/wiki/Nerve_supply_of_the_human_leg. Accessed July 24, 2020
  • Woo M. How to perform the Ultrasound Guided Femoral Nerve Block. EM Ottawa. 2018. https://youtu.be/_OugsPA4rxY Accessed July 25, 2020.
  • Warren L, Pak A. Local anesthetic systemic toxicity. UpToDate. 2019. uptodate.com/contents/local-anesthetic-systemic-toxicity. Accessed July 25, 2019.
  • Helman, A, Morgenstern, J, Spiegel, R, Lee, J. Regional Nerve Blocks for Hip Fractures. Emergency Medicine Cases. August, 2018. https://emergencymedicinecases.com/regional-nerve-blocks-hip-fractures/. Accessed July 25, 2020.
  • Haines L, Dickman E, Ayvazyan S, et al. Ultrasound-guided fascia iliaca compartment block for hip fractures in the emergency department. J of Ultrasound in Emergency Medicine 2012;43(4):692-697.

 

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EM Reflections – June 2020

Thanks to Dr Joanna Middleton for leading the discussions this month

Edited by Dr David Lewis 


Discussion Topics

  1. Antiviral Toxicity

    • Always adjust dosing in patients with renal impairment
  2. Necrotising Fasciitis

    • Difficult clinical diagnosis
    • Should be on the differential for all soft tissue infections
    • Delayed definitive care always results in poor outcomes
  3. Epidural Abscess

    • Thorough detailed neurological examination required
    • Isolated leg weakness is rare in Stroke
    • Progressive development of symproms and mixed UMN/LMN signs suggests spinal cord compression.

 


Antiviral Toxicity

Case

A 70yr old male presents with a typical zoster rash in the left L1 dermatome. He has a past medical history of chronic renal insufficiency. He is started on Valacyclovir 1000mg TID. He represents 3 days later with hallucinations including a feeling that he was occupying a dead body. What is the differential diagnosis?


 

Varicella Zoster Encephalitis vs Valacyclovir Toxicity

VZV and antiviral toxicity can present with similar symptoms

Two main risk factors increase the risk for VZV

  • age greater than 50 years old
  • immunocompromised due to reduced T cell-mediated immunity

The main risk factor for antiviral toxicity is renal insufficiency

Differentiation

  • Timing
    • Toxicity presents within 1-3 days of starting drug (vs 1-2 weeks)

 

  • Symptoms – both can present with confusion and altered LOC
    • Encephalitis – fever, HA, seizures, more likely with Trigeminal nerve (V1) or disseminated zoster
    • Toxicity – Visual hallucinations, dysphasia, tremor/myoclonus
    • Toxicity – Cotard’s syndrome…

Cotard’s Syndrome

“le délire des négations”

(delirium of negation)

https://en.wikipedia.org/wiki/Cotard_delusion

  • Described in 1880 by neurologist Jules Cotard
    • “patient usually denies their own existence, the existence of a certain body part, or the existence of a portion of their body”
  • Seen in schizophrenia, psychosis and…
  • ….acyclovir toxicity (felt to be due to metabolite CMMB (9-carboxymethoxymethylguanine) crossing BBB)

Further Reading

Varicella Zoster Encephalitis case report and outline

Valacyclovir Toxicity case report and outline

Cotard’s Syndrome

Drug Dosing in Chronic Kidney Disease

 

 

 


Necrotising Soft Tissue Infections (NSTI)

Case

A 28yr old female presents pain, redness and swelling over the right thigh. She has a past medical history of type 2 diabetes. She is managed as an outpatient with intravenous ceftriaxone q24hrs. Her symptoms failed to respond on follow up. What is the concern now? Are there any red flags? What condition needs to be considered in patients with soft tissue infections that fail to respond to antibiotics?


NSTI first described by Hippocrates 5th century BC

“[m]any were attacked by the erysipelas all over the body when the exciting cause was a trivial accident…flesh, sinews, and bones fell away in large quantities…there were many deaths.”

 

Necrotizing fasciitis is characterized by rapid destruction of tissue, systemic toxicity, and, if not treated aggressively, gross morbidity and mortality. Early diagnosis and aggressive surgical treatment reduces risk; however, it is often difficult to diagnose NF, and sometimes patients are treated for simple cellulitis until they rapidly deteriorate.

Infection typically spreads along the muscle fascia due to its relatively poor blood supply; muscle tissue is initially spared because of its generous blood supply.

Infection requires inoculation of the pathogen into the subcutaneous tissue or via hematogenous spread.

Classification

  • Type 1 – polymicrobial – older/diabetics/EtOH/IC/PVD
  • Type 2 – monomicrobial – usually group A beta-hemolytic strep (often hematogenous) – healthy people of all ages

Early signs and symptoms of NSTI are often identical to those seen with cellulitis or abscesses potentially making the correct diagnosis difficult

‘Classic’ Signs / Symptoms

(1) the presence of bullae
(2) skin ecchymosis that precedes skin necrosis
(3) crepitus
(4) cutaneous anesthesia
(5) pain out of proportion to examination
(6) edema that extends beyond the skin erythema
(7) systemic toxicity
(8) progression of infection despite antibiotic therapy or rapid progression

First 4 are “hard” signs

  • Erythema (without sharp margins; 72 percent)
  • Edema that extends beyond the visible erythema (75 percent)
  • Severe pain (out of proportion to exam findings in some cases; 72 percent)
  • Fever (60 percent)
  • Crepitus (50 percent)
  • Skin bullae, necrosis, or ecchymosis (38 percent)

Streaking lymphangitis favours the diagnosis of cellulitis over necrotizing fasciitis

Diagnosis

  • There is no set of clinical findings, lab test results and even imaging that can definitively rule out necrotizing fasciitis
    • “Surgical exploration is the only way to establish the diagnosis of necrotizing infection”.
    • “Surgical exploration should not be delayed when there is clinical suspicion for a necrotizing infection while awaiting results of radiographic imaging other diagnostic information”
  • But what if you really aren’t sure?  Or if you get pushback?
  • CT is probably the best test – esp Type 1 (gas forming)
    • Findings – gas, fluid collections, tissue enhancement, inflammatory fascial changes
  • Finger test…
    • “After local anesthesia, make a 2-3 cm incision in the skin large enough to insert your index finger down to the deep fascia. Lack of bleeding and/or “dishwater pus” in the wound are very suggestive of NSTI. Gently probe the tissues with your finger down to the deep fascia. If the deep tissues dissect easily with minimal resistance, the finger test is + and NSTI can be ruled in.”  (emergencymedicinecases.com)
  • But what about PoCUS????

PoCUS

Diagnosis of Necrotizing Faciitis with Bedside Ultrasound: the STAFF Exam

Findings – “STAFF”

ST – subcutaneous thickening
A – air
FF – fascial fluid

Ultrasound video demonstrating Subcutaneous Thickening, Air, and Fascial Fluid (STAFF).

 

Soft tissue ultrasound findings are significantly different when compared to normal soft tissue ultrasound

Bottom Line: Limited data, but basically PoCUS is not sufficient to rule-in or rule out, but might be helpful in raising suspicion level for necrotising fasciitis for physicians who routinely scan all soft tissue infections.

 

LRINF Score

The LRINEC (Laboratory Risk Indicator for Necrotizing Fasciitis) Score: A Tool for Distinguishing Necrotizing Fasciitis From Other Soft Tissue Infections

Laboratory Risk Indicator for Necrotizing Fasciitis (LRINEC) Score.  2004, retrospective – score >6 negative predictive value of 96.0% and a positive predictive value of 92%.

 

A validation study looking only at patients with pathology-confirmed necrotizing fasciitis showed that a LRINEC score cutoff of 6 points for necrotizing fasciitis only had a sensitivity of 59.2% and a specificity of 83.8%, yielding a PPV of 37.9% and NPV of 92.5%. However, the study did show that severe cellulitis had a LRINEC Sscore ≥ 6 points only 16.2% of the time.  Therefore, the available evidence suggests that the LRINEC score should not be used to rule-out NSTI.

Bottom Line: Doesn’t rule-out…… or rule-in

 

Suggested Algorithm – UpToDate

 

EM Cases Review

BCE 69 Necrotizing Fasciitis

 

Further Reading

Necrotizing fasciitis – Can Fam Physician. 2009 Oct; 55(10): 981–987.

 


Epidural Abscess

Case

A 40yr old female presents with left leg weakness. She has a complex recent past medical history including recently diagnosed pneumonia, previous renal colic and type 2 diabetes. Could this be a stroke? What are the other causes of leg weakness? How does the examination differentiate UMN from LMN lesions? When considering a diagnosis of epidural abscess what investigation is required? How soon should it be performed?


Only 4% of Strokes present with isolated or predominant leg weakness. (Brain. 1994 Apr;117 ( Pt 2):347-54.
doi: 10.1093/brain/117.2.347)

Common mechanisms of weakness:

  • Upper motor neuron lesions (Stroke, Tumour, Spinal Cord Compression, etc)
  • Lower motor neuron lesions ( Neuropathy, Disc Prolapse, Spinal Cord Compression, etc)
  • Neuromuscular junction lesions (Myasthenia, etc)
  • Neuropathies (Guillain-Barre, etc)
  • Muscle (Myopathies, etc)

Full review on Muscle Weakness from the Merck Manual here

Weakness that becomes severe within minutes or less is usually caused by severe trauma or stroke; in stroke, weakness is usually unilateral and can be mild or severe. Sudden weakness, numbness, and severe pain localized to a limb are more likely caused by local arterial occlusion and limb ischemia, which can be differentiated by vascular assessment (eg, pulse, color, temperature, capillary refill, differences in Doppler-measured limb BPs). Spinal cord compression can also cause paralysis that evolves over minutes (but usually over hours or days) and is readily distinguished by incontinence and clinical findings of a discrete cord sensory and motor level.

Unilateral upper motor neuron signs (spasticity, hyperreflexia, extensor plantar response) and weakness involving an arm and a leg on the same side of the body: A contralateral hemispheric lesion, most often a stroke

Upper or lower motor neuron signs (or both) plus loss of sensation below a segmental spinal cord level and loss of bowel or bladder control (or both): A spinal cord lesion

 

Epidural Abscess

Spinal epidural abscess (SEA) is a severe pyogenic infection of the epidural space that leads to devastating neurological deficits and may be fatal. SEA is usually located in the thoracic and lumbar parts of the vertebral column and injures the spine by direct compression or local ischemia. Spinal injury may be prevented if surgical and medical interventions are implemented early. The diagnosis is difficult, because clinical symptoms are not specific and can mimic many benign conditions. The classical triad of symptoms includes back pain, fever and neurological deterioration.

Spinal Epidural Abscess: Common Symptoms of an Emergency Condition – A Case Report

 

  • 75% are a delayed diagnosis
    • Usually hematogenous spread, usually S. aureus
  • Diagnosis
    • CRP has an sensitivity of 85%, specificity of 50%
    • MRI is gold standard
    • CT with contrast 2nd choice

 

Further Reading

Spinal epidural abscess

Episode 26: Low Back Pain Emergencies

 

 

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Lung PoCUS – Podcast

Lung PoCUS in Pediatric Emergency Medicine – Podcast

PoCUS Fellowship Clinical Pearl (RCP) May 2020

Dr. Mandy Peach (Emergency Physician and Dalhousie PoCUS Fellow, Saint John, NB, Canada)

Reviewed by Dr. David Lewis

 


Extract:

“My name is Mandy Peach and I am Emergency Physician at the Saint John Regional Hospital in Saint John, New Brunswick. I’m currently completing a PoCUS Fellowship and a pediatric rotation through the IWK Emergency Department in Halifax…….

What is the evidence for the use of PoCUS and diagnosing pediatric pneumonia. Well trained PoCUS Physicians can identify pneumonia with a sensitivity of 89% and a specificity of 94%, compared community-acquired pneumonia chest x-ray has a sensitivity of 69% and a specificity of 100%, if you see it great…. but what about early bacterial pneumonia and this case PoCUS has the upper hand, and if you consider consolidations behind the heart that can be visualized on PoCUS and obscured on chest x-ray – PoCUS 2  chest x-ray zero. So clearly it’s a useful tool to have when trying to differentiate between bacterial pneumonia that requires treatment and viral causes that would indicate conservative management. So how do we actually ultrasound the lungs…..the first step is to make the kid comfortable scan them in a position of comfort for example and their parents arms what the patient touch the ultrasound gel or the probe so it’s less of a scary thing maybe play their favourite music or YouTube video on the background or give them their favourite or snack do you want to choose a high frequency linear probe and scanning the longitudinal plane ……….”

 

Listen to the Podcast for some useful tips on performing and interpreting lung ultrasound in the pediatric population.

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Deep Dive Lung PoCUS – COVID 19 Pandemic

SJRHEM Weekly COVID-19 Rounds – May 2020

Dr. David Lewis


 

 

Part One covers aspects of core and advanced aspects of lung ultrasound application including: Zones, Technique, and Artifacts

Part Two covers PoCUS in COVID, the recent research, PoCUS findings, Infection Protection and Control, Indications and Pathways.


Part 1

 


Part 2

 

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Whose Line is it Anyway? – PoCUS in a Patient with Dyspnea

Medical Student Clinical Pearl – March 2020

Nguyet (Na) Nguyen

MD Class of 2021
Memorial University of Newfoundland

Reviewed and Edited by Dr. David Lewis

All case histories are illustrative and not based on any individual


 

Case Report

ID: 60 y/o M with dyspnea presenting to the ED late evening

HPI: Patient complained of increasing SOB starting the morning on day of presentation, with a worsening 3 days of non-productive cough. No chest pain or other cardiac features. No complaint suggestive of URTI or GI illness. Patient was given Atrovent and Ventolin en route by EMS, and was allegedly moving more air into his lungs after this intervention. Patient reports no ankle swelling, paroxysmal nocturnal dyspnea, but reports using 2 pillows to elevate himself when sleeping. Patient reports no fever, unexplained weight loss or fatigue.

Past medical history includes chronic back pain, DM, atrial fibrillation, peripheral DM-related ulcers, chronic kidney disease, BPH, colon cancer with hepatic metastases. Past surgical history significant for 5x CABG, liver and colon resection.

His medications are amitriptyline 10mg PO qhs, acetaminophen 650mg PO BID, dutasteride 0.5mg PO daily, ferrous sulfate 300mg PO daily, furosemide 40mg PO BID, metformin 500mg BID, pantoprazole 40mg PO BID, pregabalin 150mg PO BID, primidone 125mg PO daily, rosuvastatin 40mg PO qhs, rivaroxaban 15mg PO daily.

He has a distant 10 pack-years smoking history, drinks alcohol occasionally, and does not use recreational drugs. The patient lives with his wife in their own home.

Physical exam: Patient was markedly pale, non-diaphoretic, in tripod position with increased work of breathing. His temperature was 36.9, regular pulse rate at 105, respiratory rate 22, oxygen saturation 90% on room air and a nebulizer mask through which he was receiving aerosolized Atrovent and Ventolin. His BP was 125/78mmHg.

Cardiovascular exam revealed distant S1S2 in a chest with no visible deformity. His JVD was at the level of the sternal angle, there was no pedal edema bilateral. Capillary refill was 3 seconds bilateral at the thumbs. Percussion revealed no focal dullness, however on auscultation, basal crackles were heard more prominently in the right lung base, though also present on the left. There were also wheezes noted in the upper lobes heard in the anterior chest. Abdomen was soft, non-distended, non-tender. Neurological exam unremarkable.

Investigations: ECG showed sinus tachycardia with a LBBB, bloods drawn for routine labs, VBG, lactate, CXR ordered.

Differential diagnosis: AECOPD vs congestive heart failure.

PoCUS (Arrival Time + 10 mins): B-lines were observed in both lungs when a curvilinear probe was placed over different areas of the anterior chest. A small pleural effusion was also noted at the bottom of the right lung. B-lines represent increased fluid in an area of the lung, and given different clinical contexts maye represent pulmonary edema, pneumonia, or pulmonary contusion. In this case the most likely explanation for bilateral diffuse B-Lines is CHF and Pulmonary Edema. 

Working Diagnosis (Arrival Time + 10 mins): CHF and Pulmonary Edema

Management (Arrival Time + 15 mins): Pending transfer fo CXR and results of investigations the patient was treated with intravenous diuretics. He passed 500mls of urine and his symptoms improved considerably.

 

Investigations Results (Arrival Time + 45 mins): leukocytes 6.4, hemoglobin 83, platelet 165, sodium 140, potassium 5/0, chloride 101, creatinine 120, urea 11.7, glucose 17.0. Venous blood gas showed pH 7.31, pCO2 555, HCO3- 28 and lactate 2.7.

CXR (Arrival Time + 45 mins):

CXR was similar to above, this image is from: https://radiopaedia.org/cases/acute-pulmonary-oedema-6

 

Final impression: Congestive heart failure


What are B Lines?

These are the ultrasound equivalent of Kerley-B lines often reported on chest X-ray, which indicate edema in the lungs. For an exam to be positive (i.e indicative of pathology), one needs to see a minimum of 3 B-lines per view. B-lines look like flashlight beams traveling undisrupted down the entire ultrasound screen, as seen in the images above obtained during the exam.

These need to be distinguished from other artifacts such as ‘A-lines’ and ‘comet tails’. A-lines are seen in normal lungs. These are ‘repetitive reverberation’ artifacts of the normal pleura in motion. (Figure 1)(1)

‘Comet tails’- reported first by Lichenstein et al. in 1998 (although he was describing B-Lines in this paper) (Figure 2) (1), are ‘short, hypoechoic artifacts’ that only descend vertically partially down the screen. These are normal lung artifacts. This paper explains “a common misunderstanding in lung ultrasound” nomenclature that stems from Lichtenstein’s original paper.

Download pdf

 

From: https://www.mdedge.com/emergencymedicine/article/96697/imaging/emergency- ultrasound-lung-assessment

 


More on Comet Tails Artifact in this post from LitFL:

Comet tail artefact

 


 

Protocols

There are multiple protocols that guide the ultrasound technique (4) , some of which are:

  • Lichenstein et al (1998): longitudinal scans of anterior and lateral chest walls of patients in semi- recumbent position. Positive test defined as bilateral multiple B-lines diffuse anterolateral or lateral. The protocol had reported sensitivity (true positive) of 100%, and specificity (true negative) 92% for cardiogenic pulmonary edema. Blue Protocol (2015)
  • Liteplo et al (2008): anterior and lateral chest walls with patient supine: each chest divided into 4 zones (anterior, lateral, upper and lower). Positive test: pathologic pattern found in >1 zone on each side, with both sides involved.
  • Volpicelli et al. (2008): longitudinal scans of supine patients with chest divided into 11 areas (3 anterior R, 3 lateral R, 2 anterior L, 3 lateral L) to obtain score 0-11. Scores strongly correlated with radiologic and BNP (lab marker of CHF) at presentation.

 

 


 

What is the Evidence?

Al Deeb et al. conducted a systematic review and analysis of prospective cohort and prospective case-control studies in the ED, IDU, inpatient wards and prehospital settings (n = 1075). This was published in Acad Emerg Med (2014), which reported a sensitivity of 94.1% for using B-lines to diagnosis acute cardiogenic pulmonary edema (ACPE), and a specificity of 92.4% for patients with a moderate- high pretest probability for ACPE.

The SIMEU Multicenter study reported in 2015 reported a significantly higher accuracy (97% sensitivity and 97.4% specificity) with an approach incorporating lung ultrasound (LUS) in differentiating acute decompensated heart failure (ADHF) and non-cardiac causes of acute dyspnea, compared to approaches using the initial clinical workup (past medical history, history of presenting illness, physical examination, ECG, ABG), chest X-ray alone and natriuretic peptides.

Martindale et al. reported in 2016 (Academic Emergency Medicine) high positive likelihood ratio of pulmonary edema observed on lung ultrasound and low negative likelihood ratio of B-line pattern on lung US in affirming the presence of acute heart failure, after a systematic review and analysis of 57 prospective and cross-sectional studies (n = 1,918).

A useful Systematic Review “Emergency department ultrasound for the detection of B-lines in the early diagnosis of acute decompensated heart failure: a systematic review and meta-analysis ” from McGivery et al from SJRHEM (7), was published in 2018.


 

Learning Point

For a patient presenting to the ER with dyspnea, using PoCUS to observe 3 or more B-lines in two bilateral lung zones +/- pleural effusion can rapidly guide an accurate diagnosis of acute congestive heart failure.


 

References

  1. Taylor, T., Meer, J., Beck, S. Emerg Med. (2015) https://www.mdedge.com/emergencymedicine/article/96697/imaging/emergency- ultrasound-lung-assessment Last accessed Feb 29, 2020
  2. Lee, FCY, Jenssen, C., Dietrich, CF Med Ultrason (2018); 20(3): 379-384
  3. Ang SH. & Andrus P Curr Cardiol Rev. 2012 May; 8(2): 123-136https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3406272/
  4. Al. Deeb M., Barbic S., Featherstone R., Dankoff J., Barbic D. Acad Emerg Med 2014 Aug; 21(8): 843-52 https://www.ncbi.nlm.nih.gov/pubmed/25176151
  5. Pivetta E et al. Chest. 2015 Jul; 148(1): 202-210 https://www.ncbi.nlm.nih.gov/m/pubmed/25654562/
  6. Martindale JL, Wakai A, Collins SP, Levy PD, Diercks D, Hiestand BC, Fermann GJ, deSouza I, Sinert R, Acad Emerg Med. 2016 Mar; 23(3): 223-242 https://www.ncbi.nlm.nih.gov/pubmed/26910112
  7. McGivery K, Atkinson P, Lewis D, et al. Emergency department ultrasound for the detection of B-lines in the early diagnosis of acute decompensated heart failure: a systematic review and meta-analysis. CJEM. 2018;20(3):343‐352. doi:10.1017/cem.2018.27

 

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