UMEM Educational Pearls

Category: Cardiology

Title: Pseudo AMI after ICD shock

Keywords: internal cardioverter defibrillator (PubMed Search)

Posted: 4/13/2008 by Amal Mattu, MD (Updated: 7/10/2020)
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ICD shocks are often associated with ST segment elevation and even positive troponin levels that can simulate acute MI. So how do you know if the patient experienced an acute MI with VF that triggered the ICD shock? Or if there simply was an aberrant ICD shock that triggered STE with positive troponins?

STE that is due purely to the ICD shock generally resolves after only 15-20 minutes. Persistent STE beyond that time should be assumed to be true ischemia.

Troponin elevations that are due purely to an ICD shock are usually mild and normalize within 24 hours. Huge troponin elevations and those that last beyond 24 hours should be assumed to be caused by true infarction.


Category: Gastrointestional

Title: Pancreatitis

Keywords: Pancreatitis (PubMed Search)

Posted: 4/12/2008 by Michael Bond, MD (Updated: 7/10/2020)
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Some simple facts about Pancreatitis:

  1. Causes (First two are the most common in the United States)
    1. Gallstones
    2. Alcohol
    3. Hyperlipidemia
    4. Medications [azathioprine, corticosteroids, sulfonamides, thiazides, furosemides, NSAIDs, mercaptopurine, methyldopa, and tetracyclines]
    5. Peptic Ulcer Disease
    6. Scorpion and Snake Bites
    7. Trauma
    8. Infections [ ascaris, mumps, coxsackie virus, cytomegalovirus, Epstein Barr Virus, mycoplasma]
  2. Chronic Pancreatitis may not be associated with an elevation of lipase or amylase.
  3. Lipase is more specific for pancreatitis
  4. Amylase can be elevated in:
    1. pancreatitits
    2. salivary gland injury/disease
    3. ruptured ectopic pregnancy
    4. ovarian cysts
    5. salpingitis
    6. inflammation of the bowel [appendicitis, obstruction]
    7. end stage renal and liver disease [due to decreased clearance]
  5. Treatment:  mild cases can be discharged home with clear liquid diet and pain medications, more severe cases needed to be admitted for IV fluids and pain control.  Maintain NPO status.
  6. Complications:
    1. Pseudocyst
    2. Phlegmon
    3. Necrosis of the pancreas
    4. Hemorrhage
    5. Intestional obstruction
    6. fistula formation.

Category: Pediatrics

Title: Neonatal Fever - Consider HSV

Keywords: Neonatal Fever, HSV, Acyclovir (PubMed Search)

Posted: 4/11/2008 by Sean Fox, MD (Updated: 7/10/2020)
Click here to contact Sean Fox, MD

Consider HSV

  • Consider HSV as an etiology of fever in a neonate (0-30days) even without a maternal history of HSV or h/o active lesions.
    • In one study, only 12% of neonates dx’d with HSV infections had mothers with a known h/o HSV or active lesions.
  • Start Acyclovir empirically in these neonates, especially if the Gram Stain is negative.  Send appropriate HSV PCR and Cx.
    • Only 29% of patients (pediatric and adult) ultimately diagnosed with HSV encephalitis were started on acyclovir in the ED. 
    • Those who were not started on acyclovir in the ED, had a significant delay of appropriate therapy.
    • If you don’t think of it… the admitting team might not either.
       

Show References


Category: Toxicology

Title: Naloxone Tricks

Keywords: naloxone, opioids (PubMed Search)

Posted: 4/10/2008 by Fermin Barrueto, MD (Updated: 7/10/2020)
Click here to contact Fermin Barrueto, MD

1) No IV - Try naloxone in a nebulizer - Dose: 2-4 mg  and saline in your nebulizer container.

2) When using naloxone IV, use following dose: 0.05 mg IV - you will find it reverses the respiratory depression without inducing withdrawal. Anesthesia doses naloxone in micrograms, we often overdose our patients. The effect is delayed and not as pronounced as the 0.4 mg blast that causes nausea, vomiting, diarrhea, agitation - all not desirable in the ED.


Category: Neurology

Title: Does Flumazenil Really Increase Seizure?

Keywords: flumazenil. seizure, drug overdose (PubMed Search)

Posted: 4/9/2008 by Aisha Liferidge, MD (Updated: 7/10/2020)
Click here to contact Aisha Liferidge, MD

  • A recent retrospecitve study of over 830 patients with suspected or confirmed benzodiazepine overdose from the Florida State Poison Center Database showed that only 0.7% experienced subsequent seizure or seizure-like acitivity (i.e. dystonia, muscle rigidity) after flumazenil administration.
  • This study was conducted by emergency physicians from the University of Florida at Jacksonville where flumazenil is apparently often used as an antidote for benzodiazepine overdoses.

Show References


Category: Critical Care

Title: ACTH Stimulation Test

Keywords: ACTH stimulation test, adrenal insufficency, corticosteroids (PubMed Search)

Posted: 4/8/2008 by Mike Winters, MD (Updated: 7/10/2020)
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ACTH Stimulation Test

  • With the recent publication of the CORTICUS study (along with others), it is becoming clear that the ACTH stimulation test is not reliable in identifying patients with adrenal insufficiency
  • In fact, the test is no longer recommended in the evaluation of patients with severe sepsis/septic shock
  • Furthermore, if you decide to give steroids to the patient with severe sepsis/septic shock, there is no need to use dexamethasone for fear of "disrupting the ACTH stim test" (hydrocortisone is the preferred agent)

Category: Vascular

Title: DVT and Asymptomatic Pulmonary Embolism

Keywords: DVT, Pulmonary Embolism (PubMed Search)

Posted: 4/7/2008 by Rob Rogers, MD (Updated: 7/10/2020)
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DVT and Asymptomatic Pulmonary Embolism

A few important pearls about PE:

  • Remeber that up to 50% of patients with proven DVT will have asymptomatic PE at the time of presentation
  • Large, even central PE may be asymptomtic
  • Normal vital signs DO NOT rule out PE

Journal of Thrombosis and Hemostasis and Chest-2006, 2007

 


Category: Cardiology

Title: RSI of the patient with an ICD

Keywords: implantable cardioverter defibrillator, AICD, ICD, succinylcholine, intubation (PubMed Search)

Posted: 4/6/2008 by Amal Mattu, MD (Updated: 7/10/2020)
Click here to contact Amal Mattu, MD

NOTE THE CORRECTION TO THIS PEARL BELOW:

If a patient with an implantable cardioverter defibrillator needs to receive a paralytic for rapid sequence intubation, succinylcholine alone is not the best choice. The muscle fasciculations sometimes produced by succ can cause enough electrocardiographic artifact that inappropriate discharges of the ICD can occur.

Therefore, giving defasciculating doses of a paralytic before administering succ is recommended. Alternatively, use a nondepolarizing paralytic. Give 'em the rock!
Yet another reason to go with rocuronium.

AM

Dr. Ron Walls and colleagues emailed me about the pearl above, which was adapted from an article in AJEM [McMullan J, Valento M, Attari M, Venkat A. Care of the pacemaker/implantable cardioverter defibrillator patient in the ED. Am J Emerg Med 2007;25:812-822.]

The authors of the AJEM article reference another article for the statement [Stone KR, McPherson CA. Assessment and management of patients with pacemakers and implantable cardioverter defibrillators. Crit Care med 2004;32(4)Suppl:S155-S165.]. The CCM article actually states that SCH-induced fasciculations may cause artifact which may cause problems with some pacemakers, not ICDs. So it appears that there is no reported problem in using SCH in patients with ICDs. Sorry for the confusion.


Category: Obstetrics & Gynecology

Title: Bacterial Vaginosis

Keywords: Bacterial Vaginosis, Treatment, Pregnancy (PubMed Search)

Posted: 4/5/2008 by Michael Bond, MD (Updated: 7/10/2020)
Click here to contact Michael Bond, MD

Bacterial Vaginosis

  1. The most common vaginal infection in childbearing women. 
  2. Associated with burning, itching, and malodorous discharge.
  3. Cause is not fully understood but associated with
    1. douching
    2. multiple sexual partners.
  4. Complications caused by BV
    1. Increased susceptibility to HIV, HSV, chlamydia and gonnorrhea
    2. Increased risk for preterm labor.
    3. Increases the chance of an HIV woman passing HIV to her sex partner.
  5. Woman at high risk for preterm delivery should be tested for and treated for BV, however, the US Preventive Services Task Force just released a statement discouraging testing in woman at low risk for preterm delivery. 
  6. Treatment options include metronidazole and clindamycin.


Show References


Category: Pediatrics

Title: Analgesia in the Peds ED

Keywords: Analgesia, Oral Sucrose, topical lidocaine, Lumbar puncture (PubMed Search)

Posted: 4/4/2008 by Sean Fox, MD (Updated: 7/10/2020)
Click here to contact Sean Fox, MD

Tips for Common Painful Procedures:

  • Remember, kids ARE just little adults: they feel pain just like the bigger people!
    • Don't let others convince you not to consider pain management for simple procedures because it is more convenient.
  • ORAL SUCROSE
    • Proven to reduce signs of distress in neonate (<1 month) for minor, painful procedures
    • Use in combination with sucking (ie, a pacifier).
    • Dose: 0.1ml of 24% to 2ml of 50% sucrose.
  • Topical Lidocaine Creams (LMX 4, EMLA)
    • Use for IV insertion (several studies has proven skilled triage nurses ar able to predict which children will need IVs)
    • Use for Lumbar Puncture!
      • Normally you most likely either ask someone with large muscles to hold the kid or you inject lidocaine, which can obscure your landmarks.
      • Instead, place LMX4 (takes ~20minutes to produce numbness) while you are documenting, getting consent, and setting up your equipment. 
      • This will give good anesthesia and keep the kid comfortable (ie, still) and not distort your landmarks... making you more likely to have success.
      • In neonates, you can also use Oral Sucrose Pacifer for added benefit.

Show References


Category: Toxicology

Title: SUICIDE RISK WITH ANTIEPILEPTICS

Keywords: antiepileptics, suicide, carbamezepine, felbamate, gabapentin, lamotrigine, levetiracetam, valproate, pregabalin (PubMed Search)

Posted: 4/3/2008 by Ellen Lemkin, MD, PharmD (Updated: 7/10/2020)
Click here to contact Ellen Lemkin, MD, PharmD

SUICIDE RISK WITH ANTIEPILEPTICS

  • On January 31st, the FDA released a warning about an increased risk of suicidality in patients recently started on antiepileptics
  • They analyzed data across 199 placebo controlled trials, looking at 11 agents in a total of 43,892 patients
  • Patients taking antiepileptics were found to have twice the suicide ideations and attempts as those on placebo.
  • Although the overall risk was very small (0.43% vs 0.22%), it is consistent across the board, and particularly evident in those with epilepsy.

Drugs in the analysis included:
Carbamazepine (Carbatrol, Equetro, Tegretol, Tegretol XR)
Felbamate (Felbatol)
Gabapentin (Neurontin)
Lamotrigine (Lamictal)
Levetiracetam (Keppra)
Oxcarbazepine (Trileptal)
Pregabalin (Lyrica)
Tiagabine (Gabitril)
Topiramate (Topamax)
Valproate (Depakote, Depakote ER, Depakene, Depacon)
Zonisamide (Zonegran)

Interestingly, other agents including varenicline (a partial nicotinic antagonist, for smoking cessation), levetiracetam (Keppra), zolpidem (Ambien), oseltamivir (Tamiflu), isotretinoin (Accutane), and other agents have been noted to have an increased rate of bizarre and aggressive behavior.  

Show References


Category: Neurology

Title: Myasthenia Graves

Keywords: myasthenia graves, muscle weakness, weakness, edrophonium (PubMed Search)

Posted: 4/2/2008 by Aisha Liferidge, MD (Updated: 7/10/2020)
Click here to contact Aisha Liferidge, MD

  • Myasthenia Graves (MG) is a chronic, autoimmune disorder which causes voluntary (skeletal) muscle weakness.
  • In MG, antibodies block, destroy, or alter acetylcholine receptors at the neuromuscular junction (NMJ), which impedes nerve conduction to the muscle.
  • The hallmark of MG is weakness, classically of the muscles controlling bulbar function, mastication, neck movement, and facial expression, that worsens with activity and improves with rest.
  • A true MG crisis ensues once respiratory muscles weaken to the point of requiring assisted ventilation. Such a medical emergency can be triggered by fever, infection, or an adverse reaction to medication.
  • Edrophonium chloride (or Tensilon) can be administered intravenously to confirm the diagnosis of an MG attack. This drug increases levels of acetylcholine at the NMJ and temporarily relieves the symptoms of an MG.
  • Assisted ventilation, plasmpharesis, and high dose IV immune globulin can all be used to treat an acute MG crisis.
  • MG can chronically be controlled with anticholinesterase agents such as neostigmine and pyridostigmine, as well as immunosuppressives such as prednisone, cyclosporine, and azathioprine. Thymectomy is also a surgical treatment option.

Category: Critical Care

Title: Dialysis disequilibrium syndrome

Keywords: dialysis disequilibrium syndrome, mannitol, cerebral edema (PubMed Search)

Posted: 4/1/2008 by Mike Winters, MD (Updated: 7/10/2020)
Click here to contact Mike Winters, MD

Dialysis Disequilibrium Syndrome (DDS)

  • Although typically seen in ESRD patients who are being initiated on hemodialysis, DDS can be seen in the critically ill
  • Critically ill patients at risk for DDS include recent CVA, head trauma, subdural hematoma, hyponatremia,hypertensive emergency, and hepatic encephalopathy
  • Mild cases are characterized by restlessness, nausea, vomiting, headache, disorientation, and tremors
  • More severe symptoms include seizures and coma
  • The exact pathogenesis is debated but centers around acute cerebral edema
  • Treatment of DDS primarily centers around manipulation of hemodialysis
  • For the EP: patients with DDS presenting with seizures can be treated by rapidly increasing plasma osmolality with either hypertonic saline or mannitol (12.5 gms) 

Category: Misc

Title: Neutropenic Fever-Pearls and Pitfalls

Keywords: Fever (PubMed Search)

Posted: 3/31/2008 by Rob Rogers, MD (Updated: 7/10/2020)
Click here to contact Rob Rogers, MD

Neutropenic Fever

A few pearls about neutropenic fever:

  • Usually occurs a few weeks after chemotherapy (14-21 days)
  • Defined as a fever in the setting of rapidly declining neutrophil count
  • Patients who report fever at home but who are not febrile in the ED should be treated as if they are neutropenic
  • ANC=absolute neutrophil count. Calculated by adding neutrophils and bands together
  • Classification of neutropenia, use the ANC to calculate:  Mild: 1000-1500 cells/mm3, Moderate 500-1000 cells/mm3, and Severe Less than 500 cells/mm3.
  • Mortality rate increases as the ANC drops to below 500 and the duration of neutropenia. These people die of overhwhelming bacterial infections/sepsis.
  • Treatment: #1 Consider the diagnosis, #2 Broad spectrum antibiotic coverage: Imipenem, or Pip/Tazo, or Cefipime. Consider adding Vanc if the patient has a line, looks ill or is hypotensive, or if the patient has been on a fluoroquinolone.

#1 Pitfall:

  • Not initiating broad spectrum antibiotic coverage fast enough. These patients can crash very rapidly.
  • Patients do not have to be febrile in the ED to be diagnosed with this. Their report of fever is enough.
  • Mortality rates drop the faster big gun antibiotics are given. Don't be skimpy and give Unasyn. Use the big bad boys like single agent Pip/Tazo (4.5 grams, not 3.375), Cefipime, etc. Have a low threshold for adding Vancomycin.

IDSA Guidelines on Neutropenic Fever, 2002. New Guidelines coming Summer 2008!

 


Category: Cardiology

Title: cardiac tamponade and pulsus paradoxus

Keywords: cardiac tamponade, pulsus paradoxus (PubMed Search)

Posted: 3/30/2008 by Amal Mattu, MD (Updated: 7/10/2020)
Click here to contact Amal Mattu, MD

Pulsus paradoxus (exaggerated decrease in BP during inspiration) > 10 mm Hg is a physical exam finding that is often considered diagnostic of cardiac tamponade. The sensitivity of the finding, based on pooled studies, is actually only 82% and specificities are reported as low as 70%. In other words, the presence of the PP does not guarantee the presence of tamponade, and (more importantly) the absence of PP does not rule it out.

Conditions that can mask the presence of PP include hypotension, pericardial adhesions, aortic regurgitation, atrial septal defects, and RVH.

Conditions that can produce a PP in the absence of tamponade include severe COPD, CHF, mitral stenosis, massive PE, severe hypovolemic shock, obesity, and tense ascites.

The bottom line...when you are considering the diagnosis of tamponade, get the bedside ECHO. Don't hang your hat (and the patient's life!) on a pulsus paradoxus.


Category: Orthopedics

Title: DeQuervain's and Intersection Syndrome

Keywords: DeQuervain, Intersection, Tenosynovitis (PubMed Search)

Posted: 3/30/2008 by Michael Bond, MD (Updated: 7/10/2020)
Click here to contact Michael Bond, MD

DeQuervain and Intersection Syndromes:
 

  • DeQuervain's Syndrome (Tenosynovitis of the Abductor Pollicus Longus and Extensor Pollicus Brevis tendons) is a common disorder that has received a lot of press lately as BlackBerry Thumb or Gamer's Thumb.
    • This condition can be diagnosised by the Finklestein test [Have the patient bend their thumb into the palm of their hand, and then make a fist.  They should then ulnar deviate their wrist.  Pain along the tendons secures the diagnosis.]
    • The pain of DeQuervain's syndrome is typically along the distal end of the radius at the base of the thumb.
  • Intersection syndrome is a less common disorder though closely related to DeQuervain's Syndrome
    • The pain is usually felt on the top of the forearm about three inches proximal to the wrist. 
    • The pain from this condition is due to tenosynovitis of the Extensor carpi radialis longus and Extensor Carpi radialis brevis muscles/tendons caused by the intersection of them with the Extensor pollicus brevis and Abductor pollicus longus tendons.
    • Occurs due to excessive wrist movements.
    • Intersection syndrome can be seen in weight lifters, skiers, and can be seen in homeowners in the fall and winter when they rake a lot of leaves or shovel snow.
  • Treatment is the similar for both conditions and consists of:
    • NSAIDS
    • Cortisone injections can be effective
    • Thumb and wrist immobilization with a Thumb Spica Splint or Cock Up Wrist Splint
       

Category: Pediatrics

Title: Pediatric Hypertension in the ED

Keywords: Hypertension, HUS, Coarctation, renal disease (PubMed Search)

Posted: 3/28/2008 by Sean Fox, MD (Updated: 7/10/2020)
Click here to contact Sean Fox, MD

Hypertension

  • Normative BP values are based on Age, Sex, and Height (check Harriet-Lane).
  • BP should be measured in all children >3yrs and in selected children <3yrs.
  • The younger the child and the higher the BP, the more likely there is a secondary cause. 
  • Most common secondary causes:
    • 1st year of life: RenoVascular anomalies and aortic coarctation.
    • Early childhood/school-aged kids: Renal Parenchymal Disease
    • Adolescents: Essential hypertension
  • 25% of children that present with HTN requiring emergent management present with hypertensive encephalopathy (ie.  it is a more common presentation of HTN in pediatrics than in adults).
  • Initial Work-up:
    • Upper and Lower Extremity BP measurement
    • BMP and U/A – look for renal disease
    • CBC – microangiopathic process c/w HUS?


       

Show References


There is actually very little data that actually supports the administration of activated charcoal (AC) to the poisoned patient.  AC works by binding the toxin and preventing its absorption from the GI tract. Here are some of the practical points:

  • Most effective if given within one hour of the overdose
  • Do not give if patient is sedated, going to be sedated or has a chance for seizure
  • Always assess risk of aspiration versus possibly binding drug by asking the following:
  1. Is this drug dangerous enough that I have to try to prevent its absorption?
  2. Can this drug cause sedation, seizures or impair protective airway reflexes?
  3. Do I lack an antidote or alternative treatment?

Once you have assessed your risk:benefit ratio, then administer AC. Of note, it definitely works in the right situation as noted in a landmark article that showed a decrease in mortality following poisoning by oleander - a plant that contains a digoxin like substance.(1)

1 - de Silva HA, et al. Multiple-dose activated charcoal for treatment of yellow oleander poisoning: a single-blind, randomised, placebo-controlled trial. Lancet 2003: 361(9373):1935-8.



Category: Neurology

Title: Neuorproective Agents for Ishcemic Stroke

Keywords: neuroprotective agents, NXY-059, stroke, ischemic stroke, SAINT trial (PubMed Search)

Posted: 3/27/2008 by Aisha Liferidge, MD (Updated: 7/10/2020)
Click here to contact Aisha Liferidge, MD

  • Animal models have shown that neuroprotectants, including free radical trapping agents, decrease injury after ischemic stroke.
  • NXY-059 is a promising neuroprotective agent that was studied in the SAINT I and II trials.
  • SAINT I showed that NXY-059 used within 6 hours of ischemic stroke resulted in significant improvement in the primary outcome measure of reduced disability at 90 days.
  • SAINT II was done to confirm the results of SAINT I with a larger study population, but unfortunately did not show any significant difference in mortality between NXY-059 and placebo.  There was also no difference in adverse reactions, however.
  • More research is needed to determine the best neuroprotective agent to be used acutely for ischemic stroke.
  • The future of emergency treatment of ischemic stroke will likely include such agents, to be administered by emergency physicians.

Category: Vascular

Title: Treatment of Pulmonary Embolism

Keywords: Pulmonary Embolism (PubMed Search)

Posted: 3/25/2008 by Rob Rogers, MD (Updated: 7/10/2020)
Click here to contact Rob Rogers, MD

 

 

Treatment of Pulmonary Embolism

Treatment of acute PE:

  • Unfractionated Heparin (80 units/kg intravenous bolus followed by 18 units/kg/hour) or,
  • Fractionated (i.e. low molecular weight heparin) Heparin. For example, Enoxaparin, in a dose of 1 mg/kg subcutaneously every 12 hours. Some also give this dose IV every 12 hours.

If administering thrombolytic therapy (currently tPA is the only FDA approved drug) for massive PE, most authorities recommend UFH (Unfractionated Heparin) because the infusion needs to be turned off while the tPA hangs for 2 hours.

Although other agents are being promoted for the treatment of acute PE, like direct thrombin inhibitors, many institutions do not have these drugs available yet. Plus, they are expensive and have not been shown to be superior to standard therapy (at least yet)

References: Kline, Journal of Thrombosis and Hemostasis, 2005, 2006, 2007