First-degree atrioventricular (AV) block is defined as an abnormally prolonged PR-interval >200ms. Although traditionally considered to be a benign clinical entity, not all first degree AV blocks are treated the same.  

Markedly prolonged PR-intervals (PR >300ms) can cause symptoms and hemodynamic compromise due to inadequate timing of atrial and ventricular contractions. Consider the following ECG from a 32 YOF with intermittent episodes of syncope and dizziness…

There is marked first degree AV block (PR=434 ms). When the PR-interval gets too long, AV dyssynchrony compromises ventricular filling and decreases cardiac output, similar to the so-called pacemaker syndrome.

Current ACC/AHA guidelines state that permanent pacemaker implantation is reasonable for marked first degree AV block with hemodynamic compromise or symptoms similar to those of pacemaker syndrome. (Class IIa, Level of Evidence B). The guidelines caution that pacemakers are not indicated in asymptomatic patients with isolated first degree AV block.

Want more emergency cardiology pearls? Follow me @alifarzadmd

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Attachments

1310272020_ACC:AHA_Pacemaker_Guidelines.pdf (1,524 Kb)

1310272159_1st_Degree_AVB._Benign_or_Curable_Cardiac_Disease.pdf (247 Kb)

 Lateral hip pain

 Findings of weakness and/or pain while testing hip abduction may point to gluteus medius muscle dysfunction with associated with greater trochanteric pain syndrome.

The Trendelenburg test may help. The patient stands on the affected leg. A negative test result occurs when the pelvis rises on the opposite side. A positive test result occurs when the pelvis on the opposite side drops and indicates a weak or painful gluteus medius muscle.

http://www.youtube.com/watch?v=TY-G4ErruUA
 

Yesterday's pearl generated several questions that I thought were worth answering briefly:

1) Why give it IM? Absorption rate is faster than SQ infiltration though theoretically could still cause necrosis

2) Is it only infilitration? Gangrene has occurred with inadvertent intra-arterial injection, SQ infiltration and even regular IV administration

3) Mechanism? Appears to be the drug and not diluent, diluting down the concentration as well as decreasing dose appears to help if you are going to give it IV

Here is a website if you wish to read more details:

https://www.ismp.org/newsletters/acutecare/articles/20060810.asp

If you are still using IV Phenergan, you need to be aware of the necrotic effect that occurs if it infiltrates. EDs have even removed it from their drug dispensing machines. It appears to be the drug and not the diluent. Mechanism is not completely understood. Below is a picture the plaintiff attorney will use about this well know adverse effect. If so many alternatives for IV antiemetic it is wise to reconsider IV phenergan.

Attachments

1310241854_image.jpg (29 Kb)

General Information:

• 50% of victims in man-made and natural disasters are children.

• In low and middle income countries (where 95% of disasters occur), children are particularly vulnerable.

• Early responders must be well versed in caring for pediatric diarrheal disease, acute respiratory tract infections, measles, malaria, severe bacterial infections, malnutrition, micronutrient deficiencies, injuries, burns and poisonings with few resources.

• Pediatric specific triage systems have been developed to aid in resource allocation during mass casualty responses.

• Pediatric patients are singularly vulnerably to exploitation, abuse and trafficking during disaster, particularly when they are separated from their families.

Area of the world affected:

• All

Bottom Line:

• Many US based emergency medicine physicians are keen to respond to international disasters.  A clear understanding about the particular risks to children during disaster response are critical in order to care for the most vulnerable of disaster victims.

University of Maryland Section of Global Emergency Health

Author: Emilie J.B. Calvello, MD, MPH

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Background

• Acute lung injury that develops within 6 hours after transfusion of 1 or more units of blood or blood components.
• Increased risk with greater number of transfusions
• Incidence is 1 in 4000

Definition

• Acute onset
• Hypoxemia (PaO2/FiO2 < 300 mm Hg)
• Bilateral pulmonary opacities on chest x-ray
• Absence of left atrial hypertension

Pathogenesis

Two-hit hypothesis: first hit is underlying patient factors causing adherence of neutrophils to the pulmonary endothelium; second hit is caused by mediators in the blood transfusion that activate the neutrophils and endothelial cells.

Differential

Can be confused or overlap with TACO or transfusion-associated volume/circulatory overload, which presents similarly but has evidence of increased BNP, CVP, pulmonary wedge pressure, and left sided heart pressures. Patients with TACO tend to improve with diuretic treatment

Supportive tests

• Echocardiogram 
• BNP (tends to be low)
• Transient leukopenia

Treatment

• Supportive care
• Lung protective ventilation strategies
• Fluid restrictive strategy
• Aspirin (shown to be helpful in animal studies)
• Pre-washing of stored RBCs prior to transfusion
• Decrease the amount of transfusions!

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Question

55 year-old male presents with chest pain. You take a look at his cardiac function with ultrasound and here's the patient's apical four-chamber view. What's in his right ventricle and why would it be there?

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Ebstein's Anomaly

• Congenital defect of the tricuspid valve (TV) and the right ventricle (RV)
• TV septal and posterior leaflets are apically displaced resulting in "atrialization" of a portion of the right ventricle (ultimately a large right atrium and small right ventricle)
• ~40-50% of individuals with Ebstein anomaly have evidence of Wolf-Parkinson-White, secondary to the atrialized right ventricle
• ECG abnormalities include:
  • Right atrial enlargement or tall and broad P waves (Himalayan P waves) 
  • Prolonged PR interval
  • Right bundle branch block 
  • Low amplitude QRS complexes in the right precordial leads
  • T wave inversions V1-V4 and/or Q waves V1-V4

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Pediatric patients with an isolated skull fracture and normal neurological exam have a low risk of neurosurgical intervention and outpatient follow up may be appropriate (assuming no suspicion of abuse and a reliable family).  In a study published in 2011, a retrospective review over a 5 year period at a level 1 trauma center showed that 1 out of 171 admitted patients with isolated skull fractures developed vomiting.  This patient had a follow up CT showing a small extra-axial hematoma that did not require intervention.  58 patients were discharged from the ED within 4 hours.

You can also check out another recent article published in Annals of Emergency Medicine on the same topic this month!

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Drugs that cause hearing loss:

Reversible - Chloroquine, erythromycin, quinine, CO, loop diuretics, NSAIDS, ASA

Irreversible - aminoglycosides, bleomycin, vincristine, vinblastine, cisplatin, lead, mercury, arsenic

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General Information:

Trachoma is the leading cause of preventable blindness caused by an infectious disease. It is spread by direct contact with people, objects, or flies carrying Chlamydia trachomatis.  Blindness occurs due to corneal scarring with repeated infections (severe scaring of the eyelid-->eyelid inversion-->repeated corneal abrasions).

Clinical Presentation:

-Mild: Hypopigmented follicles on the inner eyelid; Moderate: inner eyelid scarring/eyelash inversion; Severe: corneal scarring/blindness (irreversible)

Diagnosis:

- Clinical: eyelid eversion and careful examination looking for the above

Treatment:

- Azithromycin 20mg/kg ONE TIME DOSE (preferred)

- 1% Tetracycline ointment bid x6 weeks

- If scarring or eyelid inversion is present, surgery is needed.

Bottom Line:

Trachoma is a clinical diagnosis and easy to treat early with a single dose of antibiotics.  Patients with late findings should be referred for surgery.

University of Maryland Section of Global Emergency Health

Author: Andi Tenner, MD, MPH, FACEP

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There have been so many great talks at ACEP 2013, but Dr. Michael Winters' talk "The ICU is NOT Ready for Your Patient" was chock full of great critical care pearls. Here are just a few:

• Increased mortality for ICU patients boarding in the Emergency Department; the increase is 1.5% per each hour of delayed transfer.
• Intubated patients should receive analgesia BEFORE sedation; fentanyl is recommended because hemodynamically stable, but you can use anything. Good analgesia will also reduce total sedative dosing
• Use continuous capnography for the intubated patient; can detect equipment malfunction and allow titration of ventilation
• Keep an eye out for abdominal compartment syndrome. Physical exam is not always conclusive, should obtain bladder pressures
• Reduce the risk of ventilator-associated pneumonia by keeping endotracheal cuff pressures adequate and keeping the head of bed elevated 30-45 degrees

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Question

A 23 year-old male presents with the rash below. He originally presented to his primary care doctor for a sore throat and was given a prescription for a medication; this rash subsequently broke out. What's the diagnosis and which medication did he receive?

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Question

A 48 year-old female presents to the ED with progressive dyspnea and chest discomfort over the past 3 months. HR = 105, BP = 100/60 mmHg, with mild JVD on exam. Her ECG is shown below. What ECG abnormalites are present? What does your differential diagnosis include? What is the best initial diagnostic test?

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Attachments

1310132023_ECGs_with_small_QRS_voltages.pdf (578 Kb)

1310132023_Low_QRS_voltage_and_its_causes.pdf (108 Kb)

Toxicologists should be aware of non-toxicological mimics of delirium, including anti-NMDA receptor encephalitis. It is an under-recognized progressive neurological disorder caused by antibodies against NMDA receptors.

Cases often present with altered mental status, autonomic instability, increased muscle tone, and movement disorders. It can easily be mistaken for neuroleptic malignant syndrome (NMS). A new case series describes two such patients for which toxicologists were consulted.

Must read links:

Dr. Leon Gussow provides a great review of the case series on his Poison Review blog.

Dr. Chris Nickson reviews the basics of the disease on the Life in the Fast Lane blog.

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General Information:

• Salmonella: gram-negative rod-shaped bacilli

• S/S: diarrhea (often bloody), fever and abdominal cramping; Incubation: 12-24hrs, duration: 4-7d

• Generally resolves without treatment. Antibiotics prolong bacterial shedding and thus only recommended in severely ill patients (high fever, severe diarrhea/dehydration, sepsis), the very young, and the very old.

Area of the world affected:

• Worldwide, especially in developing countries

Relevance to the US physician:

• As of Oct. 7^th, 278 people infected in the most recent US outbreak, thought to be related to chicken from Foster Farms

• Many of these strains of Samonella were drug-resistant

Bottom Line:

Suspect Salmonellosis in patients with appropriate exposure and symptoms, give supportive care for most, only give antibiotics to severely ill patients after sending blood and stool culture and sensitivities.

University of Maryland Section of Global Emergency Health

Author: Andi Tenner, MD, MPH

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Want to improve your chances of success in the resus room?  Download a metronome app on your smartphone and set it to a rate of 100-120 beats per minute.  There are a number of cheap (usually free) metronome applications for both iOS and Android devices.

A recent review looked at the evidence behind CPR feedback devices and found:

• Compared to baseline, chest compression rates and end-tidal CO₂ improved after activation of the metronomes.

So instead of going to iTunes and downloading the Bee Gees, go over to the App store and download a free metronome.  Your resus team will be able to stay on track with their compressions and even better - they won't have to hear you sing!

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Question

25 year-old female struck in the left hand by a football. Presents with pain, visible deformity, and the Xray below. What are the next step(s) in management?

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Acute Aortic Syndromes

Classically, aortic dissection is considered the primary culprit in patients with chest pain that radiates to the back (aortic pain) or chest pain combined with ischemia (cerebral, cardiac, peripheral), syncope, or cardiac arrest. However, it should not be your only concern: the rate of aortic rupture is much higher in penetrating atheromatous ulcer (42%) and intramural hematoma (35%) than in aortic dissection (types A 7.5% and type B 4.1%).

Chest pain with concomitant ischemic symptoms and acute decompensation should prompt consideration of several etiologies under the umbrella of aortic syndromes and not limited to dissection :

1. Penetrating atheromatous ulcer - rupture of an atheromatous plaque through the internal elastic lamina, with subsequent localized medial disruption and potential dissection, pseudoaneurysm formation, or free rupture
2. Intramural hematoma - rupture of the vasa vasorum or hemorrhage within an atherosclerotic plaque followed by aortic wall infarct
3. Aortic dissection- an intimal tear with resultant propagation within the middle third of the medial layer of the aorta
4. Aneurysm leak or rupture - progressive vessel dilation and increased wall tension
5. Traumatic transection - rapid deceleration forces or direct trauma, commonly shearing distal to left subclavian artery at aortic isthmus where the aorta is fixed by ligamentum arteriosum

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Treatment of patients with HIV/AIDS can frequently mean consideration for, and need to treat cryptoccocal meningitis.

Since 1997, studies have demonstrated that high-dose Amphotericin B combined with flucytosine has improved outcomes compared to low dose treatment or monotherapy.

A recent 2013 study reiterated this approach, showing significant decrease in deaths at 70 days post-treatment and increased rates of yeast clearance with combination therapy of Amphotericin B plus flucytosine. 

Recommendation:

Antifungal treatment of cryptococcal meningitis should start with Amphotericin B at 0.7-1 mg/kg IV daily plus concurrent flucytosine 25 mg/kg orally q6 hours. Fluconazole can be substituted in place of flucytosine if it is not available or not tolerated.

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