Friday Board Review

Board Review with Dr. Edward Guo

Edward GuoLeave a comment

An unidentified male estimated to be approximately 20 years old presents via EMS shortly after a gunshot wound to the leg. Upon arrival, he is belligerent, uncooperative with care, and subsequently intubated. Exam shows a penetrating wound to the left anterior thigh with copious pulsatile bleeding. His extremities are cool with diminished pulses throughout. FAST is negative. A compression bandage is applied. Vital signs after 1 unit of packed red blood cells are: HR 150, BP 74/52, RR 16, SpO2 99% on 40% FiO2. At this time, which of the following is indicated for the management of this patient? 

A: CT angiogram of the extremity

B: intravenous tranexamic acid

C: norepinephrine infusion

D: platelet transfusion

Answer: intravenous tranexamic acid

This patient is in hemorrhagic shock secondary to an arterial injury from a gunshot wound. The CRASH-2 trial in 2010 demonstrated that administration of intravenous tranexamic acid within 3 hours of injury for adult trauma patients with significant bleeding decreases mortality when compared to placebo. The patient is unstable with hard signs of vascular injury and should be taken immediately to the operating room. Definitive management should not be delayed for imaging. Norepinephrine and other vasopressors are not indicated as the patient is already vasoconstricted from volume loss. Additional units of packed red blood cells, not platelets, are more appropriate at this time as he is being prepared for surgical exploration and repair.

Hard Signs of Vascular Injury (ABCDE)
Active pulsatile hemorrhage
Bruit or palpable thrill
Can’t feel distal pulse
Distal ischemia
Expanding hematoma

References:
CRASH-2 trial collaborators, Shakur, H., Roberts, I., Bautista, R., Caballero, J., Coats, T., Dewan, Y., El-Sayed, H., Gogichaishvili, T., Gupta, S., Herrera, J., Hunt, B., Iribhogbe, P., Izurieta, M., Khamis, H., Komolafe, E., Marrero, M. A., Mejía-Mantilla, J., Miranda, J., Morales, C., … Yutthakasemsunt, S. (2010). Effects of tranexamic acid on death, vascular occlusive events, and blood transfusion in trauma patients with significant haemorrhage (CRASH-2): a randomised, placebo-controlled trial. Lancet (London, England), 376(9734), 23–32. https://doi.org/10.1016/S0140-6736(10)60835-5

Wednesday Image Review

What’s the Diagnosis? With Dr. Shivani Talwar

Edward GuoLeave a comment

A 36 year old male presents with left lower extremity pain after a motor vehicle vs pedestrian accident. The patient was crossing a crosswalk when a car hit him at low speed. On exam, there is an obvious deformity with significant swelling and tenderness of the left lower leg. What type of fracture pattern is present and what delayed surgical emergency can potentially occur from this injury?

Answer: Comminuted displaced fractures of distal tibia and fibula – high risk for development of Acute Compartment Syndrome

  • After a fracture, there can be extravasation of blood with increased tissue swelling and venous flow impairment within the fascial compartments. The build up in pressure causes circulatory compromise, neurologic damage, and muscle necrosis. 
  • The most common site of compartment syndrome is in the lower extremities at the tibia and fibula with a majority of cases occurring in the anterior compartment. Acute compartment syndrome can occur within a few hours of inciting trauma and can present up to 48 hours after.
  • Patient’s typically feel pain out of proportion to exam with a tense “wood-like” compartment. Alarming symptoms include:
    • Pain with passive or active stretching (most sensitive exam finding)
    • Active contraction against resistance
    • Direct pressure over the compartments
  • Diagnosis:
    • Exam findings can be sufficient to make the diagnosis in the correct setting of an inciting event along with alarming symptoms.
    • Using intracompartmental pressures alone as a guide, <30 mmHg would not require intervention whereas pressure >45 mmHg requires decompression.
    • Obtaining the “delta pressure” between the direct compartment pressure and diastolic pressure, a difference <30 mmHg should warrant fasciotomy.
  • Rapid diagnosis is key as within 3-4 hours in the muscle there can be reversible change and after 8 hours there is irreversible muscle damage; in the nerve, as soon as within 2 hours patients can have loss of nerve conduction and within 8 hours there is irreversible damage.
  • Treatment:
    • Immediately remove restrictive casts or dressings and place affected limbs at the level of the heart.
    • Surgical fasciotomy to reduce compartment pressure in a timely fashion.
      • These wounds post operatively are left open for a second operating room look within 48-72 hours for wound closure.
    • If delay in treatment, patient’s can have functional impairment including permanent neuropathy and contractures.

References:

Tintinalli’s Emergency Medicine (9th ed). Mayersak, R. J. McGraw Hill, 2018. Chapter 267 and 278. Page 1782, 1876-1879 

Torlincasi AM, Lopez RA, Waseem M. Acute Compartment Syndrome. [Updated 2023 Jan 16]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK448124/

Friday Board Review

Board Review with Dr. Edward Guo

Edward GuoLeave a comment

A 68 year old male with a history of hypertension and diabetes presents with chest pain. He was working in his yard when he suddenly felt severe, pressure across his chest. Vital signs are: Temp 98.8, HR 80, BP 162/100, RR 20, SpO2 95% RA. He appears in moderate distress and is diaphoretic. His EKG is shown below. Which of the following is NOT recommended for management of this patient?

ECG Anterolateral AMI STEMI 2

A: activation of the cath lab

B: aspirin

C: clopidogrel

D: nasal cannula oxygen

E: nitroglycerin

Answer: nasal cannula oxygen

This patient is experiencing a STEMI. His infarct is likely anteroseptal as evidenced by ST segment elevations and hyperacute T waves in V2-V4 as well as ST segment elevation in I and aVL with reciprocal ST segment depressions in III and aVF. The Air Versus Oxygen In ST-Segment-Elevation MyocarDial Infarction (AVOID) trial conducted in 2015 demonstrated that supplemental oxygen in STEMI patients without hypoxia may increase early myocardial injury and was associated with larger myocardial infarct size at 6 months. Activation of the cath lab and loading with aspirin and clopidogrel are recommended. Nitroglycerin may provide symptomatic relief for this patient but should be used cautiously in patients with evidence of right ventricular infarction. 

References:

Stub, D., Smith, K., Bernard, S., Nehme, Z., Stephenson, M., Bray, J. E., Cameron, P., Barger, B., Ellims, A. H., Taylor, A. J., Meredith, I. T., Kaye, D. M., & AVOID Investigators (2015). Air Versus Oxygen in ST-Segment-Elevation Myocardial Infarction. Circulation, 131(24), 2143–2150. https://doi.org/10.1161/CIRCULATIONAHA.114.014494

Wednesday Image Review

From the EMDaily Archives: What’s the Diagnosis? By Dr. Abby Renko

Edward GuoLeave a comment

A 45 year old male with a history of ESRD on hemodialysis and insulin dependent diabetes presents with left knee pain after slipping at work. Vitals are within normal limits. On exam, the left lower extremity is distally neurovascularly intact with palpable distal pulses. There is obvious swelling over the knee with the worst pain superior to the patella. He is unable to extend the lower leg. An x-ray is performed and shown below. What’s the diagnosis?

Answer: quadriceps tendon rupture

  • At first glance, lateral XR does not show obvious deformity… however, you may notice calcifications just superior to the patella representing retracted tendon.
  • Quadriceps tendon ruptures tend to occur in individuals > 40, while patellar tendon ruptures occur more frequently in individuals < 40.
    • Overall, quadricep tendon ruptures are more common (risk factors include rheumatologic disease, renal failure, DM, chronic steroid use).
  • In both injuries, classic exam finding is inability to extend the knee. You can often palpate a defect just above the patella in quadriceps tendon ruptures.
  • High riding patella (“patella alta”) on lateral films is more frequently seen in patellar tendon ruptures. Low riding patella (“patella baja”) may be seen on lateral film with complete quadricep tendon tear (intact patellar tendon displaces patella inferiorly).
  • X-rays may be normal! Ultrasound is the diagnostic modality of choice in the ED as it has both high sensitivity and specificity.
  • Orthopedic consultation is always warranted for these cases. Management involves a knee immobilizer and prompt follow up. Early surgical repair is associated with better outcomes in severe cases.

References:

Bengtzen RR, Glaspy JN, Steele MT. Knee Injuries. In: Tintinalli JE, Stapczynski JS, et al., eds. Tintinalli’s Emergency Medicine: A Comprehensive Study Guide. 8th ed. New York, NY: McGraw-Hill; 2016: (Ch) 274. 

Pope JD, El Bitar Y, Mabrouk A, et al. Quadriceps Tendon Rupture. [Updated 2023 Apr 22]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK482389/

Tuesday Advanced Cases & Procedure Pearls

Advanced Cases: Chest Pain with Dr. Erica Westlake

Edward GuoLeave a comment

A 25 year old female with a history of lupus presents with chest pain and shortness of breath. Her vitals are significant for tachycardia and are otherwise within normal limits. Her initial EKG is shown below:

The STEMI phone is contacted. Prior to cath lab activation, cardiology recommends a bedside echocardiogram which demonstrates the following:

Cardiology performed echocardiogram re-demonstrates a circumferential pericardial effusion without regional wall motion abnormalities or tamponade physiology. The cath lab was not activated, there was no elevation in troponins, and the patient was ultimately diagnosed with acute pericarditis.

Diagnostic Criteria for Acute Pericarditis (requires 2 of the following)
Characteristic chest pain (sharp or pleuritic, improved sitting up and leaning forward, worse lying down)
Pericardial friction rub
New or worsening pericardial effusion
Suggestive EKG changes (diffuse ST segment elevations)
  • Spontaneous Coronary Artery Dissection (SCAD) is a life threatening process involving a tear within the coronary arterial wall.
  • SCAD predominantly affects young (< 50) women especially during pregnancy and post-partum periods. It can appear identical to a STEMI on EKG despite “non-occluded” coronary vessels. It is commonly associated with a rise in cardiac enzymes and regional wall motion abnormalities on echocardiogram. It is definitively diagnosed via coronary angiography. Treatment will vary based on high vs low risk features.

References:

Diercks DB, Hollander JE, Chang A. Acute Coronary Syndromes. In: Tintinalli JE, Ma O, Yealy DM, Meckler GD, Stapczynski J, Cline DM, Thomas SH. eds. Tintinalli’s Emergency Medicine: A Comprehensive Study Guide, 9e. McGraw Hill; 2020.

Kim ESH. Spontaneous Coronary-Artery Dissection. N Engl J Med. 2020 Dec 10;383(24):2358-2370. 

Ornato, J. P., Ou, N., Radford, M. J., Tamis-Holland, J. E., Tommaso, C. L., … Zhao, D. X. (2013). 2013 ACCF/AHA guideline for the management of ST-elevation myocardial infarction: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. Journal of the American College of Cardiology, 61(4), e78–e140. https://doi.org/10.1016/j.jacc.2012.11.019

Whelan LJ. Comorbid Disorders in Pregnancy. In: Tintinalli JE, Ma O, Yealy DM, Meckler GD, Stapczynski J, Cline DM, Thomas SH. eds. Tintinalli’s Emergency Medicine: A Comprehensive Study Guide, 9e. McGraw Hill; 2020.