UMEM Educational Pearls

Category: Orthopedics

Title: Knee dislocation

Keywords: knee dislocation, vascular and nerve injury, vascular emergency (PubMed Search)

Posted: 12/26/2014 by Brian Corwell, MD (Emailed: 12/27/2014) (Updated: 12/27/2014)
Click here to contact Brian Corwell, MD

Knee Dislocation

Following reduction and immobilization, a thorough vascular assessment should follow. Any signs of vascular injury should prompt immediate vascular consultation (pallor, absent or diminished pulses)

1) Palpate popliteal and distal pulses

2) Measure ankle-brachial index (*ABI) (<0.9 = abnormal)

3) Duplex ultrasound (if available)

*ABI ratio of SBP in lower (DP/PT) and upper (brachial) extremities.

**Evaluation is often institutional specific. Discuss with your consultants.

A) If strong pulses normal ABI and normal u/s admit patient for observation with serial vascular examinations.

B) If the limb is still well perfused but the pulses are asymmetric or ABI is abnormal or US is abnormal then consult vascular surgery and obtain arteriogram (expanding role for CTA here).

C) If pulses are weak or absent or distal signs of ischemic limb then obtain emergent vascular consultation for surgical repair.



Cyanotic (right to left shunt) Congenital Heart Disease (CHD) lesions can be easily remembered with the 1,2,3,4,5 method.

1- Truncus Arteriosis (ONE trunk)

2- Transposition of the Great Vessels (TWO vessels flipped)

3- TRIcuspid Atresia

4-TETRAlogy of Fallot

5- Total Anomolous Pulmonary Venous Return (TAPVR=5 words/letters)

A few other important DUCTAL-DEPENDENT lesions: Coarctation of the Aorta, Hypoplastic Left Heart Syndrome, and Pulmonary Atresia.

Patients present to the emergency department within the first week of life in severe distress, including hypoxia, tachypnea, and hypotension.  The above cyanotic CHD all reflect DUCTAL-DEPENDENT lesions, meaning they need a widely open PDA (which closes in the first week of life) to maintain sufficient oxygenation for viability.

These patients will not survive without timely intervention with prostaglandin (PGE1), so be sure to initiate this life-saving medication as soon as possible!  Side effects include apnea…be prepared to intubate your neonate!



Category: Neurology

Title: Delirium - are we really looking for it?

Keywords: delirium, geriatric, elderly, pitfall (PubMed Search)

Posted: 12/25/2014 by Danya Khoujah, MBBS
Click here to contact Danya Khoujah, MBBS

Delirium has long been recognized as a common disorder of the geriatric ED population (seen in up to 20% of patients above the age of 65 years), but how good are we at detecting it?

Studies show that the diagnosis of delirium is made in the ED in only 11-46% of patients, which means that more than half go undiagnosed. The problem is, the risk of death at 3 months increases by 11% for every 48 hours of delirium the patient experiences, and so does their length of stay and functional decline. It is mostly missed in patients who have a baseline cognitive dysfunction, such as dementia.

So what can we do about that?

Treat delirium as a neurolgical emergency; be vigilant about diagnosing it and treating it. There are a lot of neurocognitive tests that can be used for diagnosis (such as the mini-mental status exam), but they are usually too cumbersome to use in an ED setting. The CAM (Confusion Assessment Method) has been extensively studied and has a sensitivity and specifity of about 95% to diagnose delirium. It includes the acuity of onset, fluctuant course, inattention (the hallmark), disorganized thinking and/or altered level of consciousness.

Bottom Line? Don't forget to screen your elderly patients for delirium and treat them accordingly!

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Treating ischemic strokes with interventional therapies (e.g., clot retrievers, stents, intra-arterial tPA, etc.) is nothing new, but there has never been a randomized control trial demonstrating benefit until recently.

The prospective MR CLEAN trial evaluated whether interventional therapies (i.e., either mechanical intervention or intra-arterial tPA) would confer benefit; patients were included if there was an acute occlusion within the proximal intracranial portion of the anterior cerebral circulation.

90% of patients received alteplase prior to randomization; there were 233 patients in the intervention group (alteplase + intraarterial intervention) and 267 patients in the usual care care arm (alteplase only); all patients were treated within 6 hours of symptoms onset

The primary outcome was functional independence at 90 days; an absolute difference of 13.5 percentage points favoring the intervention group was found. There were no significant differences in mortality or symptomatic intracerebral hemorrhage.

Despite these exciting results, we must pause and ask why this was this the first randomized trial demonstrating benefit when previous trials could not? Here are three blogs posts that deep dive this question and raise even more questions:

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Category: Visual Diagnosis

Title: What's the Diagnosis?

Posted: 12/21/2014 by Haney Mallemat, MD (Emailed: 12/23/2014) (Updated: 12/23/2014)
Click here to contact Haney Mallemat, MD

Question

Hand pain following fist versus face. What's the diagnosis and what nerve block would you use?

Show Answer

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Category: Cardiology

Title: Brugada Syndrome

Keywords: Brugada (PubMed Search)

Posted: 12/21/2014 by Semhar Tewelde, MD (Updated: 1/19/2015)
Click here to contact Semhar Tewelde, MD

Brugada Syndrome

Brugada syndrome is an inherited arrhythmogenic channelopathy described by ST-segment elevation in the right precordial leads and an increased risk of sudden cardiac death.

There are 3 electrocardiographic patterns:

Type 1 – Coved morphology w/ST-elevation >2 mm, followed by a negative T wave in at least 1 right precordial lead

Type 2 - Saddleback morphology w/ST-elevation >2mm, with a positive or biphasic T wave

Type 3 - Either coved, or saddleback morphology with <2mm ST-elevation

Type 1 pattern is often underestimated because of its sporadic/fluctuating appearance on ECG, which can be either spontaneously occurring or drug-induced (drug-induced variant has a more favorable prognosis).

Fever has been a well-documented culprit in unmasking Brugada pattern by increasing the sodium channel dysfunction & accelerating the late sodium current inactivation.

A recent study in a large population of patients with type 1 Brugada attempted to identify other patterns unmasking Brugada using 24-hour holter monitoring. * There is now evidence that there is a higher prevalence of type 1 Brugada pattern from 12pm-6pm & unmasking by fast and a large meal, showing influence by glucose intake and insulin levels. 

 

 

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Category: Pediatrics

Title: Respiratory season is here

Keywords: Bronchiolitis, wheezing (PubMed Search)

Posted: 12/19/2014 by Jenny Guyther, MD
Click here to contact Jenny Guyther, MD

Now that respiratory season is upon us, we are faced with an increasing number of bronchiolitis children. The updated clinical practice guidelines for managing these kids were recently published and emphasize supportive care only.

Some of the key points:


-When clinicians diagnose bronchiolitis on the basis of history and physical examination, radiographic or laboratory studies should not be obtained routinely.

-Medications such as albuterol, nebulized epinephrine or steroids should not be administered routinely in children with a diagnosis of bronchiolitis.

-Nebulized hypertonic saline should not be administered to infants with a diagnosis of bronchiolitis in the emergency department

-Clinicians may choose not to administer supplemental oxygen if the oxyhemoglobin saturation exceeds 90% in infants and children with a diagnosis of bronchiolitis

-Clinicians may choose not to use continuous pulse oximetry for infants and children with a diagnosis of bronchiolitis.

Check out the full guidelines for the quality of evidence and rational behind these recommendations.


The bottom line is that not much really works, and we just need to support their respiratory effort and ensure hydration.

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It is believed that administration of beta-blocker administration in patients with cocaine chest pain will produced increased vasoconstriction due to “unopposed alpha effect.”

 

Several retrospective studies on the use of beta-blocker in patients with cocaine-induced chest pain concluded the use of beta-blocker to be safe.

 

So is the unopposed alpha effect just a theory?

 

Lange RA et al. 1990 Ann Internal Med

Design: randomized, double-blind, placebo controlled trial.

 

30 (38- 68 years old) patients undergoing cardiac catherization for chest pain evaluation were studied.

 

Cocaine (intranasal administration) resulted in:

  • Increased myocardial oxygen demand
  • Increased coronary vascular resistance 22%
  • Decreased coronary sinus blood flow: 10%

 

Administration of propranolol (intracoronary infusion) resulted in additional:

  • Increase coronary vascular resistance 19%
  • Decrease coronary sinus blood flow by 15%
  • No additional change in myocardial oxygen demand

 

Complete coronary occlusion observed in 1 patient with ST elevation

Epicardial coronary arterial segment constriction >10% in 5 patients.

 

Bottom Line: Lange RA et al. 1990 demonstrates that the “unopposed alpha effect” does occur in coronary artery when beta-blocker is administered in a setting of acute cocaine exposure.  Overall, the use of beta-blocker in the ED management of cocaine-induce acute chest pain is not a prudent option.  It is unknown if the cocaine dose, last use of cocaine (days), or CAD history influence the “safety” of beta-blocker initiation/use during inpatient hospitalization.

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Background:  As discussed previously, influenza (flu) is a common respiratory disease that causes significant morbidity and mortality worldwide (see pearl from October 1. 2014).  We are now in the midst of the current flu season.

 

Current Update: This year’s vaccine was only a partial match (<50%) for the current influenza A (H3N2) circulating virus, so there is a significant potential for a “bad” flu season with widespread disease and severe illness.  Currently, influenza is now widespread throughout the US, with some states reporting more activity than others.  The CDC has a weekly surveillance map that highlights current disease spread.

 

Bottom Line:

  • Remember that influenza annually causes between 250,000 and 500,000 deaths worldwide.
  • Your emergency department will likely see many individuals with influenza this year, even if the patient received the vaccination.
  • Know your emergency department protocols and policies for cohorting influenza patients  and addressing droplet isolation precautions.

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Attachments

1412180413_CDC_Flu_Map_Week_49_2014.jpg (199 Kb)



How does it present?

  • Fever, cough, sore throat, runny nose, muscle aches, headaches, fatigue, diarrhea (in children especially)

Who cares…I got my vaccine! Does the vaccine work this year?

  • There has been some antigenic drift this year in the influenza A (H3N2) type virus.
  • 52% are anti-genically different than the H3N2 vaccine virus.
  • So the vaccine is less effective this year but it can give some cross-protection (in addition to protection against the other strains used in the vaccine)
  • CDC recommends still getting the vaccine  (http://www.cdc.gov/flu/protect/vaccine/vaccines.htm)
  • 91% of samples reported to the CDC have been influenza A this year

Can I test for this?

  • Rapid influenza diagnostic tests check for antigen detection
  • Pooled sensitivity of 62%; specificity of 98%
  • False negatives are common
  • Good technique during sample collection is important

The CDC is recommending treatment...wait I thought we were done with Tamiflu?

  • Benefits: shortens the duration of symptoms (day or less), reduces the risk of complications, reduces the risk of death among hospitalized patients
  • Risks: side effects (see below)
  • A recent Cochrane review revealed that treatment did not really help reduce complications and most of the data on anti-viral agents is biased (Roche funded) and hotly debated

Who is at risk/who deserves consideration for treatment?

  • Hospitalized patients with influenza 
  • Old people (>65)
  • Children
  • Pregnant women
  • Chronic medical conditions (asthma, COPD, diabetes, or heart disease)
  • American Indians and Alaskan natives
  • Chronic immunosuppression
  • Institutional outbreaks (nursing homes, correctional facilities)

Pearls of treatment

  • Treat as early as possible (<48hours from symptom onset)
  • 5 days of treatment; twice daily dosing. Wt based for children. Renally dosed.
  • Oseltamivir: used for more severe influenza cases
  • Zanamivir: 7 years or older; IV Zanamivir is currently in Phase III clinical trials

What are the side effects of anti-viral agents?

  • Don’t use zanamivir in patients w/ pulmonary disease
  • Transient neuropsychiatric events for oseltamivir
  • Nausea, vomiting, diarrhea are common both both

 

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Question

A patient is intubated for respiratory failure and the post-intubation CXR is shown on the left. 30 minutes later the patient desaturates and another CXR is obtained (the one on the right). What’s the diagnosis and what should you do?

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Not So Benign: Benign early repolarization (BER) effects in STEMI

- Benign early repolarization (BER) has been associated with increased risk of sudden cardiac death and ventricular fibrillation (VF) in patients with and without structural heart disease.

- Acute STEMI is associated with high incidence of ventricular arrhythmias and the most frequent cause of sudden cardiac death in the adult population.

- BER has been associated with arrhythmogenicity, however the prognostic importance of this ECG finding in patients with STEMI has not been well elucidated.

- In a recent prospective study of STEMI patients, BER was associated with higher rates of in-hospital ventricular arrhythmias and mortality; It is an independent predictor of long-term mortality beyond well-known other parameters. 

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Category: Pediatrics

Title: Hirschsprung's disease

Posted: 12/13/2014 by Rose Chasm, MD (Updated: 9/20/2024)
Click here to contact Rose Chasm, MD

  • Irregular bowel movements and constipation are a common complaint pediatric complaint.
  • The majority of cases are functional, but providers should take extra care to rule out organic causes like Hirschsprung's disease particularly during the neonatal period. 
  • 1 in 5000 incidence, with abnormal innervation of the distal colon resulting in tonic contraction, and obstruction of feces.
  • In most cases, the agangionic segment is limited to the rectosigmoid area.
  • Symptoms usually begin in the first month of life and consist of obstuctive complications such as abdominal distension, bilious vomiting, and poor feeding.
  • Rectal examination should be done in all patients with constipation, and often reveals a narrowed high-pressure region adjacent to the anal sphincter.
  • Barium enema, anal manometry, and rectal biopsy all aid in the diagnosis.

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Category: Toxicology

Title: In-hospital outcomes for beta blocker use in cocaine-chest pain

Keywords: cocaine, chest pain, beta blocker (PubMed Search)

Posted: 12/1/2014 by Bryan Hayes, PharmD (Emailed: 12/11/2014) (Updated: 12/11/2014)
Click here to contact Bryan Hayes, PharmD

Should beta blockers be withheld in cocaine-chest pain patients?

A new study retrospectively compared patients who received beta blockers as an inpatient to those who did not. Even though the beta blocker group had higher risk clinical characteristics, there was no difference in the composite primary end point of myocardial infarction, stroke, ventricular arrhythmia, or all-cause mortality within 24 hours of beta blocker use.

Important Limitations

The potentially dangerous interaction between beta blockers and cocaine is likely a much larger issue in patients with very recent cocaine use in the setting of a catecholamine surge. A retrospective analysis likely doesn't include those patients.

Application to Clinical Practice

While this study doesn't answer the question about beta blocker use in acute cocaine toxicity, it does provide some reassurance about the safety of beta blockers given for cocaine-related chest pain.

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Category: Neurology

Title: Can we decrease CT utilization in mild TBI?

Keywords: clinical decision support, clinical decision rules, head CT, mild traumatic brain injury (PubMed Search)

Posted: 12/10/2014 by WanTsu Wendy Chang, MD
Click here to contact WanTsu Wendy Chang, MD

Does clinical decision support help reduce head CT utilization in mild traumatic brain injury related ED visits?

  • Mild traumatic brain injury (mTBI) account for approximately 1.2 million outpatient visits per year
  • Almost 1 million of these mTBI patients undergo head CT as part of their evaluation
  • Less than 6% have significant intracranial injuries that require neurosurgical intervention

Are we utilizing clinical decision rules adequately to help us appropriately select patients for CT imaging?

Can clinical decision support (CDS) help us reduce head CT utilization in mTBI related ED visits?

  • A recent study by Ip et al. reported on the use of a real-time computerized CDS in an EMR/CPOE system to provide feedback to an ordering provider on "low utility" CT's based on clinical decision rules (New Orleans Criteria, Canadian CT Head Rule, CT in Head Injury Patients Prediction Rule)
  • Over a 2 year period, 1221 of 1988 (64%) of mTBI related ED visits were associated with a head CT being performed
  • A 13.4% decrease in CT utilization was seen in the CDS intervention group (58.1% pre- vs. 50.3% post-, p=0.005)
  • A control cohort using the National Hospital Ambulatory Medical Care Survey (NHAMCS) as a representative of emergency medical care delivered in the U.S. showed no significant change in CT utilization in the same time period (73.3% pre- vs. 76.9% post-, p=0.272)

Take Home Point:

Clinical decision support may be a useful tool to help reduce CT utilization in mild TBI related ED visits.

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The Critically Ill Patient with Ebola Virus Disease

  • The current outbreak of Ebola Virus Disease (EVD) is the largest ever recorded and has been declared "a public health emergency of international concern" by the WHO.
  • Pearls regarding critically ill patients within the current EVD outbreak include:
    • Clinical Features
      • Tachycardia, tachypnea, oliguria, and alterations in mental status are common and generally seen about 7-12 days after symptom onset.
      • Shock is often due to profound hypovolemia from GI losses.
      • Hemorrhage is a late finding and most often manifests as lower GIB.
    • Labs
      • Common lab abnormalities include hypokalemia, hypocalcemia, hypoalbuminemia, and lactic acidosis.
    • Treatment
      • The mainstay of treatment is aggressive fluid resuscitation and electrolyte repletion (especially potassium).
      • Blood products can be administered for those with coagulopathy and hemorrhage.
      • Empiric antibiotics and antimalarial medications should be considered while awaiting confirmatory testing for EVD.

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Question

Patient was found in a house fire and was given a certain medication in the Emergency Room. The patient’s urine turned this color (red), what’s the diagnosis?

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Predictors of Cardiac Rupture After AMI

- In the era of revascularization and aggressive cardiac care there has been a continual decline in acute myocardial infarction (AMI) mortality rates; however one of the most deadly complications, cardiac rupture (left ventricular free wall, ventricular septum, or papillary muscle rupture), still remains relatively stable.

- Cardiac rupture is an increasingly more frequent cause of death during AMI, thus a recent study retrospectively assessed the clinical and morphologic variables in those with and without cardiac rupture that were hospitalized for AMI.

- Cardiac rupture overwhelmingly complicates a first AMI.

- Cardiac rupture occurs most often in patients with an immense quantity of cardiac adipose tissue, the size of the left ventricular cavity is typically normal, and the area of the infarct is small.

- Heart failure patients with prior AMI have healed scar tissue and are at nominal risk of complications such as rupture if a subsequent AMI occurs.  

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Category: Pharmacology & Therapeutics

Title: Is that IV antibiotic dose before ED discharge really necessary?

Keywords: antibiotic, IV, diarrhea (PubMed Search)

Posted: 11/25/2014 by Bryan Hayes, PharmD (Emailed: 12/6/2014) (Updated: 12/6/2014)
Click here to contact Bryan Hayes, PharmD

Many of the oral antibiotics prescribed in the ED have good bioavailability. So, a one-time IV dose before discharge generally won't provide much benefit.

In fact, a new prospective study found that a one-time IV antibiotic dose before ED discharge was associated with higher rates of antibiotic-associated diarrhea and Clostridium difficile infection. [1] One-time doses of vancomycin for SSTI before ED discharge are also not recommended (see Academic Life in EM post).

Bottom Line

Though there are a few exceptions, if a patient has a working gut, an IV dose of antibiotics before ED discharge is generally not recommended and may cause increased adverse effects. An oral dose is just fine. 

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Category: Toxicology

Title: Rhabdo Prevalence

Keywords: Sympathomimetic toxicity, Synthetic cathinones, Rhabdomyolysis (PubMed Search)

Posted: 12/4/2014 by Kishan Kapadia, DO
Click here to contact Kishan Kapadia, DO

Sympathomimetic toxicity is a known toxidrome that is complicated by the development of rhabdomyolysis.  There are multiple stimulant agents that induce sympathomimetic toxicity including, synthetic cathinones, cocaine, amphetamines, and methamphetamines.  

A recent retrospective, single-center, chart review in the age range of 14-65 years sought to determine the prevalence of rhabdomyolysis in patients with sympathomimetic toxicity and compare rates among patients using specific agents.  Rhabdomyolysis and severe rhabdomyolysis were defined as CK>1000 and 10,000 IU/L, respectively.

Rhabdomyolysis occurred in 42% of study subjects (43/102)

Prevalence in 89 subjects due to a single-stimulant exposure:

Rhabdomyolysis 

1) Synthetic cathinone (MDPV, alpha-PVP) 63% (12/19)

2) Methamphetamine 40% (22/55)

3) Cocaine 33% (3/9)

4) Other single agents (methylphenidate, pseudoephedrine, phentermine) 0% (0/6)

Severe Rhabdomyolysis

1) Synthetic cathinone 26% (5/19)

2) Methamphetamine 3.6% (2/55)

3) Cocaine 11% (1/9)

4) Other single agents (methylphenidate, pseudoephedrine, phentermine) 0% (0/6)

In this study, patients exposed to synthetic cathinones were more likely to develop rhabdomyolysis and severe rhabdomyolysis compared to the non-cathinone-exposed group.

Bottom Line:

Be aware of this increased risk from synthetic cathinones along with other stimulants.  Treat aggressively with IV fluids, rapid correction of hyperthermia, benzodiazepines to control manifestations of sympathomimetic toxicity to reduce muscle activity and metabolic demand.

 

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