Friday Board Review

Pharmacology Board Review with Dr. Edward Guo

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A 30 year old non-pregnant female presents after a cat bite to her left hand. Vitals are within normal limits. The extremity is neurovascularly intact and shows two subcentimeter punctate lesions on the palmar surface of her hand. She reports an anaphylactic reaction to penicillin. Which of the following antibiotics is appropriate prophylactic treatment for this patient?

A: amoxicillin-clavulanate

B: clindamycin

C: cephalexin

D: doxycycline

Answer: doxycycline

Prophylactic antibiotic treatment is common practice of mammalian bites in the ED. Antibiotics should be tailored for coverage of streptococcal and staphylococcal bacteria as well as anaerobes and Pasteurella multocida. Amoxicillin-clavulanate is typically the antibiotic of choice but is contraindicated in patients with an anaphylactic allergy to penicillin. Clindamycin or cephalexin monotherapy do not reliably cover Pasteurella species. Doxycycline or dual therapy with clindamycin plus TMP-SMX or a fluoroquinolone are reasonable alternatives for penicillin-allergic patients.

References:

Quinn J (2020). Puncture wounds and bites. Tintinalli J.E., & Ma O, & Yealy D.M., & Meckler G.D., & Stapczynski J, & Cline D.M., & Thomas S.H.(Eds.), Tintinalli’s Emergency Medicine: A Comprehensive Study Guide, 9e. McGraw Hill.

Presutti R. J. (2001). Prevention and treatment of dog bites. American family physician, 63(8), 1567–1572.

Wednesday Image Review

From the Archives: What’s the Diagnosis? By Dr. Sandhya Ashokkumar

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A 5 year old male with a history of sickle cell disease (SCD) complicated by splenic sequestration presents to the ED with complaints of hip and back pain. He has had the pain for days, but now over the last 24 hour has had decreased PO intake associated with nausea, vomiting, and chest pain.  Mom reports fever at home and that he appears to be having difficulty breathing. Vitals include BP 108/62, HR 152, T 99.2F, RR 40, SpO2 88% on room air. On exam, he appears uncomfortable and has clear lung sounds. A chest x-ray is performed and shown below. What’s the diagnosis?

Answer: Acute Chest Syndrome – note the opacification of the posterior costophrenic sulcus on the lateral film concerning for pneumonia

Definition: New infiltrate on chest x-ray in addition to fever > 101.3F, cough, wheeze, tachypnea, or chest pain

  • Clinical features may present before radiographic changes, and patients may develop acute chest during hospitalization for another SCD complication.
  • Chest x-ray has an approximately 85% sensitivity, thus obtain a chest CT if chest-x ray is non-diagnostic with high index of suspicion.

Etiology: Pulmonary infection, fat emboli, vaso-occlusion, over aggressive fluid administration

  • Most common organisms are Chlamydia pneumoniae and Mycoplasma (other organisms are Staph aureus, Haemophilus influenza, Klebsiella pneumonia, and respiratory viruses)
  • Consider Strep pneumoniae in patients with sickle cell disease not taking prophylactic penicillin

Treatment:

  • Oxygen for hypoxia
  • Pain control
  • IV fluids  – correct hypovolemia with isotonic fluid bolus, usually starting with 20 mL/kg if no heart failure; thereafter maintain euvolemia with maintenance oral hydration or IVF (D5NS or D5.45NS)
  • Antibiotics to cover atypical organisms and encapsulated organisms
  • Beta-2 adrenergic agonists for wheezing
  • Exchange transfusion reserved for severe crisis (and PaO2<60 or high hemoglobin)

Pitfall: These patients can decompensate quickly with increasing oxygen requirements and often require critical care!

References:

Long B, Koyfman A. Sickle Cell Disease and Hereditary Hemolytic Anemias. 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

Friday Board Review

Cardiology Board Review by Dr. Alex Hilbmann

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You are asked to see a patient with a known history of Left Ventricular Assist Device (LVAD) due to end stage heart failure who presents after becoming more confused in the Emergency Department waiting room. Per family the patient was originally presenting due to feeling lightheaded/fatigued recently. The patient does not have a pulse and the automatic/manual blood pressure cuff does not determine a blood pressure. Patient cannot follow commands but localizes to pain in all four extremities. Capillary refill < 2 seconds. What should be done next?

A. Begin chest compressions

B. Auscultate heart

C. Point of care echocardiogram

D. Portable CXR

Answer: Auscultate heart

The first thing that should be done for this patient is auscultate his heart to note if an audible “whirr” is present. If it is present, this would indicate that his LVAD is in fact operating. Patients who have an LVAD do not have a palpable pulse/blood pressure therefore in this population it does not indicate that their LVAD is currently not working/they are not perfusing. An ultrasound with doppler may be used to obtain a blood pressure reading. Chest compressions should be withheld until absolutely necessary given the chance to potentially dislodge the LVAD causing dysfunction or left ventricular rupture. The chance of chest compressions causing damage to LVAD can be minimized by paying attention to positioning of compressions and avoiding unnecessarily deep compressions. It would be reasonable to begin compressions if low perfusion state suggested by exam (mental status change, skin mottling, capillary refill >2 seconds). Auscultation of the heart would be the most timely and effective method in recognizing functionality of patient’s LVAD. Given patient’s exam concerning for altered mental status without other findings for low perfusion, CPR can briefly be held until further evaluation determines concern for hypoperfusion.

References:

Guglin, Maya (2018) “Approach to Unresponsive Patient with LVAD,” The VAD Journal: Vol. 4, Article 2.
DOI: https://doi.org/10.13023/VAD.2018.02
Available at: https://uknowledge.uky.edu/vad/vol4/iss1/2

Tintinalli, J., Ma, O., Yealy, D., Meckler, G., Cline, D., Thomas, S. and Stapczynski, J., 2020. Tintinalli’s emergency medicine. 9th ed. [New York]: McGraw-Hill Education, pp.382

Yuzefpolskaya M, Uriel N, Flannery M, Yip N, Mody K, Cagliostro B, Takayama H, Naka Y, Jorde UP, Goswami S, Colombo PC. Advanced cardiovascular life support algorithm for the management of the hospitalized unresponsive patient on continuous flow left ventricular assist device support outside the intensive care unit. Eur Heart J Acute Cardiovasc Care. 2016 Dec;5(8):522-526. doi: 10.1177/2048872615574107. Epub 2015 Mar 4. PMID: 25740223.

Wednesday Image Review

What’s the Diagnosis? By Dr. Edward Guo

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A 3 year old male with a history of severe eczema presents for facial rash and hand pain. Mom has been applying aquaphor and vaseline several times a day. This morning, he woke up with a new rash over his face and hands which prompted ED visit. Vitals include BP 103/61, HR 156, Temp 102.9F, RR 30, SpO2 99%. Exam is notable for diffuse, dry skin throughout and findings as below. Lesions spare mucous membranes and palms/soles. Nikolsky sign negative. What’s the diagnosis?

Answer: Eczema Herpeticum

  • Demonstrated by multiple grouped pustules on an erythematous base
  • Typically caused by superinfection of HSV due to a diminished skin barrier from atopic dermatitis
  • Commonly misdiagnosed as impetigo
  • Potentially life-threatening if has multisystem involvement such as HSV keratitis or encephalitis
    • In this case, ophthalmology was consulted to rule out ophthalmologic infection due to extensive rash. Dermatology was consulted for a wound culture which resulted positive for VZV.
  • Treatment includes Acyclovir in addition to gram positive coverage such as Bactrim or Cephalexin

References:

American Academy of Pediatrics: Herpes simplex. In: Kimberlin  DW, Brady  MT, Jackson  MA, Long  SS, eds. Red Book: 2015 Report of the Committee on Infectious Diseases. 30th ed. Elk Grove Village, IL: American Academy of Pediatrics; 2015:432–445.

Tuesday Advanced Cases & Procedure Pearls

“Allergic Reaction” by Dr. Edward Guo

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Case: A 34 year old male with a past medical history of polysubstance use is brought in via EMS for an “allergic reaction.” He woke up this morning with tightness in his jaw and legs which has progressed to the inability to open his mouth or walk. Per chart review, the patient was in the ED yesterday acutely agitated and received intramuscular sedation with haloperidol and midazolam. On exam, his vitals are within normal limits. He speaks in full sentences through clenched teeth. Visualization of the oropharynx is limited due to inability to open his jaw. His bilateral lower extremities demonstrate rigid hyperflexion and inversion at the ankle joints. He is otherwise neurologically intact without abnormal findings on skin or lung exam.

Differential diagnosis includes: allergic reaction, extrapyramidal reaction, tetanus

Pearls:

  • This patient is likely presenting with an extrapyramidal reaction secondary to receiving haloperidol, a high-potency antipsychotic.
    • Extrapyramidal symptoms include acute dystonia, akathisia, Parkinsonism, tardive dyskinesia, and neuroleptic malignant syndrome.
    • The pathophysiology involves an imbalance of dopaminergic and cholinergic activity, not a true allergic reaction.
  • Acute dystonia is typically self-limited and not life-threatening with the exception of rare cases of laryngospasm.
    • Treatment includes benztropine (dopamine agonist) or diphendydramine (anticholinergic).
    • Patients that are discharged from the ED with resolution of symptoms should be given PO benztropine or diphenhydramine for 2 to 3 days due to prolonged effects of antipsychotics that can result in rebound dystonia.
  • Drug induced Parkinsonism and tardive dyskinesia usually develop after prolonged use of antipsychotics and are less likely to be reversible.

Case continued: The patient received 50 mg IV diphenhydramine with near immediate resolution of his symptoms. He was observed for a brief period in the emergency department, ambulated, and tolerated PO without difficulty and was shortly thereafter discharged.

References:

Levine M, LoVecchio F. Antipsychotics. 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.