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Handover from EMS to Trauma Team: an analysis

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Scaphoid Fracture – Can PoCUS disrupt the traditional ‘splint and wait’ pathway?

 

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:

A 37 year old, right hand dominant, carpenter presents to your local ED with a complaint of right wrist pain. He was on a step-stool and lost his balance earlier today. He fell landing on his outstretched arm and had an acute-onset of radial-sided wrist pain. He denies any other injury. There are no neurologic complaints.

On exam, there is no visible deformity. The skin is closed and there is some swelling noted. The patient is tender over the anatomic snuff box as well as volarly over the scaphoid. There is pain noted with axial loading of the thumb. There is no other tenderness. ROM is within normal limits. The limb is distally neurovascularly intact.


X-rays are normal.

An occult scaphoid fracture is suspected. At this institution, patients with suspected occult scaphoid fracture are placed in a thumb spica splint and referred to the local hand surgeon to be seen in ~10-14 days for repeat assessment and X-ray.

Can Point of Care Ultrasound change this traditional “splint and wait” patient pathway?


 

Background:

Scaphoid fracture is a common presentation to the Emergency Department accounting for approximately 15% of all wrist injuries and 70% of carpal fractures. Up to 30% of the time, radiographs at initial presentation appear normal making fracture a commonly missed injury for Emergency physicians. A failure to recognize this injury can lead to chronic pain and functional impairment for patients. Particularly, fractures of the proximal pole (most distant to the blood supply) can lead to avascular necrosis (AVN) at high rates. Non-union can lead to scaphoid non-union advanced collapse (SNAC wrist) which can perpetuate further degenerative changes throughout the carpus. This can cause a significant impact on quality of life and occupation. Early detection of fracture could expedite fixation and possibly results in better outcomes. Further study in this area is needed.


 

Anatomy:

The scaphoid bone lies in the radial aspect of the proximal carpal row. It’s unique shape (“twisted peanut”), lends to easy recognition. It articulates proximally with the distal radius, distally with the trapezium, and on its’ ulnar aspect with the lunate to form the scapho-lunate interval. The blood supply to the scaphoid is unique in that the majority of it is retrograde. The dorsal carpal branch of the radial artery supplies the bone from distal to proximal. A small proportion of the blood supply originates at the proximal end. The boundary between the two supplies creates a “watershed” area prone to non-union and AVN.


 

Classification of Fractures:

Scaphoid fractures are classified by location. These regions are the proximal, middle and distal thirds which account for 20%, 75%, and 5% of the fractures respectively. The stability of fractures is determined by the displacement (>1mm) and angulation (scapholunate angle >60 and radiolunate angle >15). The Hebert Classification as endorsed by Traumapedia can be found below.


 

Traditional Imaging:

Imaging of these suspected injuries varies. Traditionally serial X-rays were used, but have been found to be poorly sensitive even several weeks after injury. Bone scan has also been used as an alternative due to it’s high sensitivity, but has poor specificity and provides no further information regarding the nature of the fracture. CT is relatively sensitive and specific and provides information for pre-operative planning. MRI is considered the gold standard, but is difficult to obtain in a timely manner in Canada.

Bäcker HC, Wu CH, Strauch RJ. Systematic Review of Diagnosis of Clinically Suspected Scaphoid Fractures. J Wrist Surg. 2020 Feb;9(1):81-89. doi: 10.1055/s-0039-1693147. Epub 2019 Jul 21. PMID: 32025360; PMCID: PMC7000269.


 

PoCUS Technique:

  • Linear probe

  • Consider waterbath, gel standoff pad, or bag of IV fluid

  • Scan with the wrist ulnarly deviated

  • Scan in the longitudinal and transverse orientations of volar, lateral and dorsal aspects

  • Place the probe in longitudinal orientation dorsally over lister’s tubercle of the radius and scan distally until the scaphoid is visualized in the snuff box. Scan radial to ulnar.

  • Rotate to the transverse orientation and scan through proximal to distal

  • Volarly, in the transverse plane, identify the tendon of the flexor carpi radialis (this lies radial to the easily identifiable palmaris longus tendon on exam). The scaphoid is found deep to this. Scan proximal to distal.

  • Rotate to the longitudinal orientation and scan radial to ulnar

 


 

Video Demonstration:

 


 

Findings:

  • Cortical disruption

  • Periosteal elevation

  • Hematoma


 

The Evidence:

  • Early advanced imaging (CT or MRI) compared to initial 2 week immobilisation proved more cost effective and had better patient oriented outcomes (ie. missed work).(7)
  • A systematic review and meta analysis of moderate to high quality studies published in 2018 found that ultrasound had a mean sensitivity of ~89% and specificity of ~90% for detection of occult scaphoid fractures.(1)
  • Similar results were also reported by another systematic review in 2018.(8)
  • Pocus was shown to have a comparable sensitivity to CT for occult scaphoid in a systematic review published in 2020.(2)

 

Limitations:

  • Only useful if positive
  • Operator experience dependent
  • US probe and frequency dependant
  • Potential for false positives due to injury of nearby structure causing hematoma
  • Potential for false positives in context of arthritis or remote trauma

 

Bottom line:

  • Useful if positive
  • Still need definitive test to further delineate fracture (ie: for operative planning)
  • Could expedite CT
  • Could expedite specialist follow-up
  • May improve ER physician diagnostic certainty
  • May improve patient trust and compliance with splinting
  • Further study is needed

 

Case Conclusion:

Scaphoid cortical disruption was visualized using PoCUS. After discussion with the hand surgeon, a CT Scan of the wrist was performed which confirmed a minimally displaced waste fracture of the scaphoid. The patient was splinted and seen the next day in clinic for discussion regarding operative management.


 

Further Review:

 

 


 

References

  1. Ali M, Ali M, Mohamed A, Mannan S, Fallahi F. The role of ultrasonography in the diagnosis of occult scaphoid fractures J Ultrason 2018; 18: 325–331.
  2. Bäcker HC, Wu CH, Strauch RJ. Systematic Review of Diagnosis of Clinically Suspected Scaphoid Fractures. J Wrist Surg. 2020 Feb;9(1):81-89.
  3. Bakur A. Jamjoom, Tim R.C. Davis. Why scaphoid fractures are missed. A review of 52 medical negligence cases, Injury, Volume 50, Issue 7, 2019, Pages 1306-1308.
  4. Carpenter CR et al. Adult Scaphoid Fracture. Acad Emerg Med 2014; 21(2): 101-121.
  5. Gibney B, Smith B, Moughty A, Kavanagh EC, Hynes D and MacMahon PJ American Journal of Roentgenology 2019 213:5, 1117-1123
  1. Jenkins PJ, Slade K, Huntley JS, Robinson CM. A comparative analysis of the accuracy, diagnostic uncertainty and cost of imaging modalities in suspected scaphoid fractures. Injury. 2008;39:768–774.
  2. Karl, John W. MD, MPH1; Swart, Eric MD1; Strauch, Robert J. MD1 Diagnosis of Occult Scaphoid Fractures, The Journal of Bone and Joint Surgery: November 18, 2015 – Volume 97 – Issue 22 – p 1860-1868.
  3. Kwee, R.M., Kwee, T.C. Ultrasound for diagnosing radiographically occult scaphoid fracture. Skeletal Radiol 47, 1205–1212 (2018).
  4. Malahias MA, Nikolaou VS, Chytas D, Kaseta MK, Babis GC. Accuracy and Interobserver and Intraobserver Reliability of Ultrasound in the Early Diagnosis of Occult Scaphoid Fractures: Diagnostic Criteria and a Way of Interpretation. Journal of Surgical Orthopaedic Advances. 2019 ;28(1):1-9.
  5. Mallee WH, Wang J, Poolman RW, Kloen P, Maas M, de Vet HCW, Doornberg JN. Computed tomography versus magnetic resonance imaging versus bone scintigraphy for clinically suspected scaphoid fractures in patients with negative plain radiographs. Cochrane Database of Systematic Reviews 2015, Issue 6.
  6. Mallee, W.H., Mellema, J.J., Guitton, T.G. et al. 6-week radiographs unsuitable for diagnosis of suspected scaphoid fractures. Arch Orthop Trauma Surg 136, 771–778 (2016).
  7. Melville, D., Jacobson, J.A., Haase, S. et al. Ultrasound of displaced ulnar collateral ligament tears of the thumb: the Stener lesion revisited. Skeletal Radiol 42, 667–673 (2013).
  8. Meyer, P., Lintingre, P.-F., Pesquer, L., Poussange, N., Silvestre, A., & Dallaudiere, B. (2018). Imaging of Wrist Injuries: A Standardized US Examination in Daily Practice. Journal of the Belgian Society of Radiology, 102(1), 9.
  9. Mohomad et al. 2019. Accuracy of the common practice of doing X-rays after two weeks in detecting scaphoid fractures. A retrospective cohort study. Hong Kong Journal of Orthopaedic Research 2019; 2(1): 01-06.
  10. Neubauer J, Benndorf M, Ehritt-Braun C, et al. Comparison of the diagnostic accuracy of cone beam computed tomography and radiography for scaphoid fractures. Sci Rep 2018; 8:3906.
  11. Ravikant Jain, Nikhil Jain, Tanveer Sheikh, Charanjeet Yadav. 2018. Early scaphoid fractures are better diagnosed with ultrasonography than X-rays: A prospective study over 114 patients, Chinese Journal of Traumatology, Volume 21, Issue 4, Pages 206-210.
  12. Senall, JA, Failla, JM, Bouffard, JL. 2004. Ultrasound for the early diagnosis of clinically suspected scaphoid fracture. J Hand Surg Am, 29:400-405.
  13. https://essr.org/content-essr/uploads/2016/10/wrist.pdf
  14. http://www.bonetalks.com/scaphoid
  15. https://radiopaedia.org/articles/scaphoid-fracture
  16. https://sketchymedicine.com/2014/07/scaphoid-bone-anatomy-and-fractures/
  17. https://radiopaedia.org/cases/scaphoid-fracture-11?lang=gb
  18. https://www.orthobullets.com/hand/6034/scaphoid-fracture
  19. https://meeting.handsurgery.org/abstracts/2018/EP15.cgi
  20. https://www.researchgate.net/figure/Bone-scintigraphy-patient-C-of-the-hands-the-patient-with-a-scaphoid-fracture-on-the_fig4_50399987
  21. https://www.youtube.com/watch?v=7pCXiRQMRKo&t=5s&ab_channel=UltrasoundPod
  22. https://litfl.com/terry-thomas-sign
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EM Reflections January 2021: TIA Review

 

Big thanks to Dr. Paul Page for leading discussions this month.

All cases are theoretical, but highlight important discussion points.

Authored and Edited by Dr. Mandy Peach

Case

A 69 yo male presents to the ED with dizziness that was ongoing 1 hour. His symptoms began when getting up from the couch and walking to the kitchen. He felt like he was going to ‘pass out’ and ‘couldn’t walk straight’. He also describes having a headache that began around the same time, but says he has headaches from time to time and wasn’t bothered by it. After 1 hour of feeling dizzy and off balance he called EMS. His symptoms resolved en route with EMS in the ambulance.

His vitals in triage are: 128/64, HR 89, RR 16 O2 95% on RA, T 36.3 Glucose 15

The nurse hands you his medication list and ECG

The ECG indicates atrial fibrillation. This is new from his previous ECG. His medications include ramipril, metformin and atorvastatin.

You suspect a transient ischemic attack (TIA), but what other mimics are on the differential1?

 

What are some important causes of TIA to consider? What features make TIA more likely1?

You feel your patient’s abrupt inability to walk straight certainly qualifies as lack of function. The onset was abrupt and symptoms have resolved. Your patient also has new atrial fibrillation, putting them at risk.

What if the patient didn’t have new atrial fibrillation? What other symptoms/features on clinical exam could suggest an alternative cause1?

Think “TIA and”…

TIA and neck pain: cervical artery dissection

TIA and new fever or heart murmur: endocarditis

You complete your physical exam. The patient is neurologically normal including cranial nerves, motor, sensory, reflexes, cerebellar, and gait. There is no new murmur, fever or neck pain. The patient has new a fib of unknown duration that is not anticoagulated. You suspect this is the cause.

Although the patient is normal now, you do wonder if they had objective signs initially with EMS, or with the first nursing assessment. As neuros can change so quickly you review the other documented exams

Of note EMS reports a GCS of 15 and the following description of symptoms:

“off balance, requiring support to walk”

“noticeable trouble speaking with slurred speech”

“patient reports feeling dizzy”.

The symptoms resolved en route. The patient walked unassisted from the ambulance bay to triage.

Nursing notes document a normal neuro exam in triage.

Is there a timeline involved in diagnosis TIA2?

TIA is now defined as a transient episode of neurologic dysfunction caused by focal brain, spinal cord, or retinal ischemia, without acute infarction. The end point, stroke, is biologic (tissue injury) rather than an arbitrary timeline (≥24 hours).

Although the patient is now neurologically normal, this episode is a big red flag for stroke. To determine how urgent a work up is needed you decide to stratify the patient’s risk of stroke. The ABCD2 score likely comes to mind:

 

Is this tool accurate at predicting stroke3?

With the ABCD2 score physicians may misclassify up to 8% of patients as low risk. The sensitivity of the score for high risk patients was found to be only 31.6%3. This score also does not take into account neuroimaging findings – one study found up to 15% of patient’s with high grade carotid stenosis would be missed by using the ABCD2 score. Lastly an Australian study that used the ABCD2 score with ED patients all reported similar rates of strokes at the 30 and 90 day follow up, regardless of stratification using this tool.

Bottom line – ABCD2 is out.

So is there any tool I can use to predict risk of stroke4?

The Canadian TIA Score

This score was initially studied prospectively in over 7500 adult patients diagnosed with TIA in the ED or by a neurologist. The primary outcome was subsequent stroke in 7 days or prompt emergency carotid endarterectomy (CEA) to prevent stroke in less than 7 days. 1.4% of patients had a stroke and 1.0% had CEA in less than 7 days.

The score has recently been validated and is ready for clinical use8.

This score classifies patients as:

LOW risk: -3 to 3 points. Safely discharge following careful ED assessment with elective follow up

MEDIUM risk: 4-8 points. Undergo additional testing in the ED, have antithrombotic therapy optimized, be offered early stroke/neuro follow up

HIGH risk: ≥ 9 points. Fully investigate and manage ideally in consultation with a stroke specialist during the first ED visit.

Your patient is already at medium risk, before imaging is acquired. According to this tool your patient should be investigated with labs and imaging in the ED and offered urgent neuro follow up.

The acute nurse reminds you that it is 2330 and the CT tech leaves at midnight. You need to arrange urgent imaging – but what should you order6?

CT-angiography can be done at timing of non contrast CT and is the standard of care in neurovascular disease. It is well established that there is an association between vascular occlusion or high grade stenotic vessels and stroke recurrency and disability.

Angiography will show high grade stenotic lesions that are amendable to endarterectomy, as well as identify carotid or vertebral artery dissection as an alternative cause.

In high risk patients, CT-A should be the go to. This is based on Canadian Stroke Best Practice Guidelines.

 

Based on the Canadian TIA score my patient is medium risk. Could they still benefit from CT-A?

The Canadian TIA Score is not yet integrated with Stroke Management. According to Best Practice Guidelines high risk features are considered to be:

This patient had transient speech deficit – consider this a high risk feature and get a CT-A in your work up in the department.
You discuss this with your radiologist who agrees a CT-A is warranted.

Luckily a consultant neurologist is also on call and in house dealing with a patient in the neuro ICU. As this patient requires urgent neuro follow up he agrees to see post CT-A.

Your patient has 50% stenosis of the left vertebral artery. There is no sign of infarct or hemorrhage and no space occupying lesion.

The patient is assessed by neuro, while a trauma and STEMI roll into your department. You get back to work.

An hour later the neurologist speaks with you briefly after seeing the patient and agrees this is a TIA. Their plan is to initiate anticoagulation as they suspect a cardio-embolic source as the CT shows no infarct/dissection and the symptoms resolved within an hour. They plan to order an urgent echo and follow up with the patient this week and feel they can be discharged.

What would be a contraindication to starting anti-coagulation for A fib1?

Evidence of completed stroke on CT – these patients are started on anti-coagulation at a later date to prevent bleeding into infarct.

You wonder if the patient should be admitted as they had high risk features in their presenting TIA?

If the patient has a negative CT with no occlusion and no vessels amenable to endarterectomy then they can be discharged and followed-up within 48 hours1.

If there is an occlusion ameanable to endarterectomy, then admission is advisable. Urgent surgery can reduce the risk of stroke over 2 years from 26% to 9% (a 17% absolute risk reduction). If done within 2 weeks the absolute risk reduction is 30%1. This is generally the case for carotid stenosis.
Our patient has vertebral artery stenosis – which usually maximizes medical therapy before considering any surgical options7. If the patient had carotid stenosis, high grade stenosis of over 70% would warrant urgent consultation.

After this consideration you feel more comfortable with the plan and continue the rest of your shift.

You are reviewing the case with a student learner later in the shift and they ask what if the patient didn’t have A fib? What would have been the course of action1?

Investigations 1:
The patient would require holter and echo to assess for potential cardioembolic source from paroxysmal A fib. If admitted these would have beeen done as an inpatient. However, our patient was discharged. More urgent holter and echo is required for patients who:

“1. Patients with known heart disease including rheumatic heart disease, heart failure, severe valvular disease, severe CAD or history of MI.
2. Patients with no obvious cause of their TIA and no classic risk factors to identify an underlying cause of their TIA such as paroxysmal atrial fibrillation, severe valvular disease including endocarditis, PFO etc.”

Management 1:
Early dual antiplatelet therapy (DAPT) initiated within 24-72 hours and continued for 3 weeks decreases risk of stroke by up to 3.5% without increased risk of bleeding.

In the ED: load with ASA 160-325mg PO and Plavix 300mg PO
Discharge: on ASA 81 mg PO daily and Plavix 75mg PO daily x 3 weeks only

After the discussion with the neurologist the patient was discharged and given good advice on symptoms of CVA to return for. He left the ED.

 

1 week passes and you are working an evening shift. There is a stroke patient brought into the trauma bay to be urgently seen – you recognize the same 69 yo male you saw a week earlier with a TIA. On evaluation the patient has symptoms of a posterior circulation stroke. He is slightly dysarthric but can get out some slurred speech. You review his medication list and there is no anti-coagulant. You confirm with the patient he did not start any new medications after leaving the ED a week ago. When asked why he didn’t fill the prescription from the neurologist he communicates that he did not receive one.

What is the risk of stroke following TIA8?
Up to 10% of patients with TIA will have a CVA in 7 days, up to 12% in 90 days.

 

Patients in the ED are our patients, even when evaluated by a consultant and deemed well enough for discharge. In this situation confirming with the consultant who will be providing the prescription as well as confirming the patient has one in hand before leaving the department would have greatly benefited the patient.

 

 

References and further reading:

Helman, A, Himmel, W, Dushenski, D. TIA Update – Risk Stratification, Workup and Dual Antiplatelet Therapy. Emergency Medicine Cases. November, 2018. https://emergencymedicinecases.com/tia-update/. Accessed Feb 9, 2021

Furey & Rost. (2020). Initial evaluation and management of transient ischemic attack and minor ischemic stroke. Uptodate. https://www.uptodate.com/contents/initial-evaluation-and-management-of-transient-ischemic-attack-and-minor-ischemic-stroke?search=tia&source=search_result&selectedTitle=1~150&usage_type=default&display_rank=1#H3011236877. Accessed Feb 9, 2021

Long. Updates on TIA. emDocs. April 2016. http://www.emdocs.net/8538-2/. Accessed Feb 9, 2021

Helman, A. Morgenstern, J. Klaiman, M. Sayal, A. Perry, J, Reid, S. Rezaie, S. EM Quick Hits 18 – Conservative Management Pneumothorax, Microdosing Buprenorphine, Practical Use of CRITOE, Canadian TIA Score, Pediatric Surviving Sepsis Guidelines, Safety of Peripheral Vasopressors. Emergency Medicine Cases. May, 2020. https://emergencymedicinecases.com/em-quick-hits-may-2020/. Accessed Feb 10, 2021.

https://emergencymedicinecases.com/wp-content/uploads/2018/11/Canadian-Stroke-Guidelines-summary-2018-CJEM-1.pdf

American Heart Association (2018). Role of Brain and Vessel Imaging for the Evaluation of Transient Ischemic Attack and Minor Stroke. Stroke. Vol 49 (7) pg 1791-1795

Furie. (2019). Secondary prevention for specific causes of ischemic stroke and transient ischemic attack. Uptodate. https://www.uptodate.com/contents/secondary-prevention-for-specific-causes-of-ischemic-stroke-and-transient-ischemic-attack?sectionName=LARGE%20ARTERY%20DISEASE&search=tia&topicRef=1123&anchor=H2&source=see_link#H3. Accessed Feb 10, 2021

Perry et al. (2021). Prospective validation of Canadian TIA Score and comparison with ABCD2 and ABCD2i for subsequent stroke risk after transient ischaemic attack: multicentre prospective cohort study. BMJ 2021; 372:n49.

 

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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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