April 28, 2014

D-dimer testing is sensitive for thrombus formation, and in patients who are not high risk, this test is used to rule-out venous thromboembolism. D-dimer has been shown to increase with age, which can cause a lower specificity (i.e. more false positive tests) in older patients.  Specificity can range from 49 - 67% in patients ≤ 50 years of age, but in older patients (i.e. ≥ 80 years of age) the specificity is quoted as 0 - 18%. The result of this is, older patients often have more diagnostic imaging, but a higher cut-off may lead to increased false negative cases (i.e. missed VTE) and make this strategy less safe. So could age adjusted d-dimer testing increase specificity without affecting sensitivity?

April 21, 2014

Patients with corneal abrasions typically come to the emergency department for eye pain.  Most physicians treat these with topical antibiotics, oral analgesia, and for those who are lucky enough 48 - 72 hour follow up with ophthalmology. Oral analgesia does a poor job of controlling these patients pain. Tetracaine is an esterase type anesthetic with a onset of action of 10 - 20 seconds and a duration of action of 10 - 15 minutes.  Use of topical anesthetics are very effective at reducing pain, but there use is discouraged secondary to poor wound healing of the corneal epithelium.  So what is the evidence for topical anesthetic use on corneal abrasions?

REBEL Review 63: Treatment of Hyperkalemia

Created April 18, 2014 | Endocrine, Metabolic, Fluid, and Electrolytes | DOWNLOAD

April 17, 2014

Hyperkalemia is an electrolyte abnormality seen in the emergency department as well as in hospitalized patients and it can be associated with adverse clinical outcomes and death if not treated appropriately. It is important to remember that the electrophysiologic effects of hyperkalemia are directly proportional to both the absolute plasma potassium and its rate of rise. However, neither the ECG nor the plasma potassium alone are an adequate index of the severity of hyperkalemia, and therefore providers should have a low threshold to initiate therapy. Classic teaching of the chronological ECG changes of hyperkalemia include:
  1. Peaked T waves
  2. Prolongation of PR interval
  3. Widening QRS Complex
  4. Loss of P wave
  5. "Sine Wave"
  6. Asystole

REBEL Review 62: Asthma-Like Syndromes

Created April 15, 2014 | Thoracic and Respiratory | DOWNLOAD