Modern Resident - The newsletter of AAEM/RSA
February/March 2012
Volume 3: Issue 5


2011-2012 Leadership

President
Teresa M. Ross, MD

Vice President
Zachary Repanshek, MD

Secretary-Treasurer
Leana Wen, MD MSc

Immediate Past President
Ryan Shanahan, MD

At-large Board Members
Ali Farzad, MD
Stephanie Gardner, MD
Sarah Terez Malka, MD
Taylor McCormick, MD
Ketan Patel, MD

Medical Student Council President
Meaghan Mercer

Modern Resident Contributors

Copy Editor: Taylor McCormick, MD
Managing Editor: Jody Bath, AAEM/RSA Staff

Taylor McCormick, MD; Veronica Theresa Tucci, MD JD; James Gillen, MD FACEP; Casey Grover, MD; Michael Pulia, MD FAAEM; Meaghan Mercer, MSIV; John V. Abraham, MS4; Khoa Tu, MS4; Heather Boynton, MS1; Carlos Ramos, MSIV; and Mary Calderone, MS2.

Interested in writing?

Email submissions to: info@aaemrsa.org

Please submit articles by April 15th for the April/May edition.

Opinions expressed are those of the authors and do not necessarily represent the official views of AAEM or AAEM/RSA.


Updates from the RSA Board of Directors

The Scientific Assembly
Meaghan Mercer, MSIV
Western University of Health Sciences
AAEM/RSA Medical Student Council President

"Emergency Medicine doesn't eat its young." One of my favorite statements from this year's AAEM Scientific Assembly, and although amusing, it is grounded in a solid truth. As Dr. Amal Mattu stepped up to the podium on the first day, I was surrounded by a room packed full with emergency medicine students, residents and attendings. Being wrapped up in a crowd of people that share a passion for the field and a mutual desire for each other's success is an inspiring and empowering feeling.

I am currently a fourth year medical student, and I started attending AAEM events as a first year medical student. These experiences have driven both my passion for the field as well as my success. The lectures are not only cutting edge, but full of wisdom. Advice like "learn one thing everyday day and do it humbly" or "treat people the way they want to be treated" is interspersed amongst most advanced discussions in emergency medicine. At the opening reception, I fully realized the lack of traditional hierarchy in the field as I stood deep in conversation with a second year medical student, an international ultrasound guru, an editor of a prestigious emergency medicine journal and renowned attendings from across the nation. Leaders in this field are not masked in a pretention; they are approachable and encouraging. These events are bursting with potential contacts, mentors and, most importantly, life-long friends. AAEM has provided me with a home in the field of emergency medicine, and I look forward to each opportunity to reconvene with my EM family. Thank you to everyone who made my week in San Diego as special as it was, and we will see you all in Las Vegas next year!

Congratulations to the new 2012-2013
RSA Board of Directors and Medical Student Council
.


Commentary/Letters to the Editor

Fellow Human Beings
John V. Abraham, MS4
Florida State University College of Medicine

In September, I filmed a video documenting the lives of three homeless men and the struggles they face on a daily basis. In the process of making this film, I worked closely with Health Care for the Homeless in Baltimore and spent a great deal of time meeting members of the homeless community and learning their life stories. What I captured in my video only begins to tell the story of the disempowering effects of poverty and how it can permeate through all aspects of a homeless adult's life. I quickly realized the therapeutic value of the interview process. Several of the individuals I met spend their lives in a state of social isolation, persistently vulnerable and silenced by a community disinterested in the issues they face. In the process of reflecting on their own life stories, many have found these weakening experiences have actually made them stronger.

The most valuable experience for me was putting away the white coat and the camera and sitting down with the people at the homeless shelter. I heard them speak candidly about life on the streets and the obstacles preventing them from functioning in society. Learning about these issues firsthand has inspired me as a future EM physician and has defined what I want my role to be in the community.

http://vimeo.com/johnvabraham/fellowhumanbeings


EM:RAP

We would like to announce an exciting new FREE benefit for all paid AAEM/RSA members. Paid AAEM/RSA members now have FREE access to Emergency Medicine: Reviews and Perspectives (EM:RAP)! This outstanding monthly educational podcast, which ordinarily costs a resident $195/year, is now yours for FREE!

Click here to log in to your AAEM/RSA member's only account. Once logged on, you will be taken to the EM:RAP site. If you already have an EM:RAP account, you may log in with that username and password. If not, you will need to create an account. Please contact us with any questions.


Board Review

Aortic Dissection
Khoa Tu, MS4
University of California, Irvine School of Medicine
Taylor McCormick, MD
Los Angeles County+University of Southern California Emergency Medicine

A 62 year-old male is brought in by ambulance for acute onset left lower extremity weakness, numbness and pain. En route to the ED he complained of ripping chest pain, and on arrival he was hypotensive, bradycardic and hypothermic. CT aortogram is shown below.

AAEM: Aortic Dissection AAEM: Aortic Dissection AAEM: Aortic Dissection

(Click image to enlarge)

Aortic dissection occurs via two mechanisms: an intimal tear followed by a column of blood dissecting through a weakened medial layer causing formation of a false lumen, or rupture of vasa vasorum and direct hematoma formation within the vessel wall (10% of cases). Involvement of the ascending aorta occurs in 70% of cases (Stanford type A), and involvement distal to the left subclavian artery occurs in 35% of cases (Stanford type B). The incidence of aortic dissection is estimated at 10,000 cases annually, roughly, 1 in 10,000 emergency department visits. Despite its rarity, the in-hospital mortality rate for this disease is 27.4%. Mortality is highest within the first 7 days after onset. The most common causes of mortality are cardiac tamponade, aortic rupture and visceral ischemia. Common past medical and surgical history associated with aortic dissection include hypertension (72% of cases), atherosclerosis (31%), known aortic aneurysm (16%), prior dissection (6.4%), aortic valve replacement (5.4%), diabetes mellitus (5.1%), Marfan's syndrome (4.9%), and CABG (4.3%).

Aortic dissection can present with a wide array of symptoms including sharp pain (90% of cases), abrupt pain (84.8%), chest pain (72.7%), back pain (53.2%), abdominal pain (29.3%), radiating pain (28.3%), migrating pain (16.6%), and syncope (9.4%). Physical findings include hypertension SBP>150 mmHg (49% of cases), normotension SBP 100-149 mmHg (34.6%), hypotension SBP<100 mmHG (8%), shock SBP<80 mmHg (8.4%), aortic insufficiency murmur (31.6%), pulse deficit between different limbs (15.1%), CHF (6.1%), and CVA (4.7%). Of note, Type A dissections are more likely to present in shock and cardiac tamponade (13-18% vs. 2%).

Historically, aortography was the gold standard of diagnosis but is now rarely used. TEE, helical CT and MRI all have similar sensitivity and specificity (98% and 95%, 100% and 98%, 98% and 98%, respectively). TEE has advantages of being done at the bedside without contrast or radiation. MRI has advantages of being noninvasive, providing visualization of intimal tears, also without contrast or radiation. However, helical CT is the most common initial diagnostic modality chosen because it is more easily available, faster and least operator dependent. Chest X-rays can detect abnormalities in up to 80-90% of cases, but findings are nonspecific. Electrocardiography is useful for ruling out MI (dissection can travel retrograde into the right coronary ostium in 3% of cases) but are normal in 31% of cases, and most findings are nonspecific. Recently, a novel guideline-based tool for identification of acute aortic dissection has been proposed, Aortic Dissection Detection Risk Score, with high sensitivity (95.7%).

Emergency management of aortic dissections is focused on two goals: reduction of blood pressure and decrease in the rate of rise of arterial pulse (dP/dt), or shear force. The systolic blood pressure goal and heart rate goals are 100-120 mmHg and <60 beats per min. Therapies include opioids for pain control, beta-blockers for BP and HR (shear force) control and vasodilators if additional BP control is needed. A titratable beta-blocker such as esmolol is ideal, followed by a vasodilator such as nitroprusside for optimal BP control once reflex tachycardia has been prevented. In general, Type A dissections go to the operating room, and Type B dissections go to the ICU or interventional radiology to restore patency of occluded major arteries. Type A dissections have a 27% in-hospital mortality rate when managed surgically vs. 58% with non-surgical management. Mortality increases from Type B dissections with surgical management (11% vs. 31%).

Our patient with a Type A dissection in the case above presented somewhat atypically and serves as a reminder that aortic dissection should be thought of as the chest pain and syndrome. Consider this diagnosis in patients presenting with chest pain and syncope, chest pain and lower extremity symptoms, chest pain and stroke, chest pain and AI murmur with heart failure, chest pain and marked hypertension, or chest pain and a clinical picture that doesn't seem to add up.

References:

  1. Gilligan et al. Rosen's Emergency Medicine, Concepts and Clinical Practice. 2010. 7th ed., Vol. 1, pp. 1188-1192.
  2. Khan IA, Nair CK. Clinical, diagnostic, and management perspectives of aortic dissection. Chest. 2002 Jul;122(1):311-28.
  3. Hagan et al. The International Registry of Acute Aortic Dissection (IRAD): new insights into an old disease. JAMA. 2000 Feb 16;283(7):897-903.
  4. Rogers et al; IRAD Investigators. Sensitivity of the aortic dissection detection risk score, a novel guideline-based tool for identification of acute aortic dissection at initial presentation: results from the international registry of acute aortic dissection. Circulation. 2011 May 24;123(20):2213-8.
  5. Gilon et al. International Registry of Acute Aortic Dissection Group. Characteristics and in-hospital outcomes of patients with cardiac tamponade complicating type A acute aortic dissection. Am J Cardiol. 2009 Apr 1;103(7):1029-31.

Pediatric Pharmaceutical Poisonings on the Rise
Heather Boynton, MS1
Georgetown University School of Medicine

As Americans take more and more medications on a regular basis, pharmaceutical poisonings of children are on the rise.  A recent study by Bond et al. (2011) looked at Poison Control Center data from 2001-08 and found a 30% increase in children under 5 years of age visiting emergency departments (EDs) for medication poisonings.  Bond et al. report a 43% increase in injuries and a 36% increase in hospitalizations. There are now more injuries in small children due to medication exposure than motor vehicle accidents, and the severity is increasing along with the number.

The largest part of the burden on EDs seems to be from children ingesting prescription medication on their own. Three types of medications are associated with the highest number of total ED visits and increased admission and/or injury rate—opioids, cardiovascular agents and sedative-hypnotics. While one or two tablets of beta or calcium channel blockers may have relatively mild effects such as hypoglycemia, clinically important symptoms rise with dose.  Of the 66 deaths directly related to pediatric pharmaceutical poisoning from 2001-08, more than half were due to opioid analgesic or cardiovascular drugs.

What can we do to help bring these numbers down? Patient education is an important part of the equation.  All medications should be stored in child-resistant containers and more importantly, out of the reach of small children.  Another analysis of Poison Control Center data suggested that ease of access to medication was the only statistically significant factor in pediatric poisonings. Medications should not be stored on tables or countertops, on low shelves or in purses. New flow-restriction packaging and single tablet-dispensing containers would also help prevent poisonings. The Advocacy Committee will have downloadable patient handouts on pediatric pharmaceutical poisonings and other topics on the RSA website soon.

References:

  1. Bond GR, Woodward RH, Ho M. The growing impact of pediatric pharmaceutical poisoning. J Pediatr. 2012 Feb;160(2):265-270.e1. Epub 2011 Sep 13.
  2. Budnitz DS, Lovegrove MC. The last mile: taking the final steps in preventing pediatric pharmaceutical poisonings. J Pediatr. 2012 Feb;160(2):190-2. Epub 2011 Nov 5.
  3. Benson BE, Spyker DA, Troutman WG, Watson WA, Bakhireva LN. Amlodipine toxicity in children less than 6 years of age: a dose-response analysis using national poison data system data. J Emerg Med. 2010 Aug;39(2):186-93. Epub 2009 Jun 17.
  4. McFee RB, Caraccio TR. ‘‘Hang up your pocketbook’’—an easy intervention for the granny syndrome: grandparents as a risk factor in unintentional pediatric exposures to pharmaceuticals. J Am Osteo Assoc. 2006;106(7):405-11.

AAEM/RSA Toxicology Handbook!

The SECOND EDITION of the AAEM/RSA Toxicology Handbook is now available! Check it out -- along with our other great texts -- at the AAEM bookstore at aaem.org/bookstore! Order yours today!

The Toxicology Handbook is an easily accessible reference of common toxicological emergencies. It is authored primarily by toxicologists from a wide range of academic programs and backgrounds, who focused on the clinical aspects of common ingestions, with a special emphasis on the "tricks of the trade" that specialists in the field acquire with time and experience. We hope that you will find it useful in the care of poisoned patients.


EM Board Review - Electrical Injuries
Carlos Ramos, MSIV
Veronica Theresa Tucci, MD JD
James Gillen, MD FACEP
University of South Florida Emergency Medicine

1. A 29 year-old male is brought into the emergency department by EMS approximately 20 minutes after being electrocuted while installing a ceiling fan. He is unresponsive on scene. When paramedics connect him to the monitor he is found to have an arrhythmia. Which of the following is most likely to have developed?

a. EM Board Review - Electrical Injuries
b. EM Board Review - Electrical Injuries
c. EM Board Review - Electrical Injuries
d. EM Board Review - Electrical Injuries

2. What would be the best course of action to treat the electrocardiographic findings of the above patient?

  1. Attempt unsynchronized cardioversion (defibrillation)
  2. Attempt synchronized cardioversion
  3. Attempt pharmacological cardioversion with magnesium sulfate
  4. Administer lidocaine to re-stabilize myocardium

3. A 65 year-old construction worker with a past medical history of hypertension on enalapril is brought into the emergency department about 4 hours after having come in contact with a crane impregnated with high-voltage wire and was electrocuted on scene. He weighs 70 kg and demonstrates the skin findings pictured below:

Which of the following is true regarding fluid resuscitation?

AAEM AAEM AAEM
AAEM
  1. Should be given as a standard fluid bolus for severe dehydration
  2. Should be calculated as 4 ml X 70 kg X TBSA and given with albumin to maintain blood pressure due to losses secondary to fourth degree burns
  3. May require greater than 4 ml X 70 kg X TBSA due to possibility of deep tissue involvement
  4. Should be less than 4 ml X 70 kg X TBSA to prevent excess oxygen demand on the heart if he develops an arrhythmia

4. A 24 year-old woman G2P1A0 in her 33rd week of gestation is brought into the ED unresponsive, approximately 30 minutes after she was struck by lightning during a storm. All resuscitative efforts are in progress, and during her physical exam she is found to have profuse vaginal bleeding. Which of the following is the most likely cause of her vaginal bleeding?

  1. Pre-term labor from the stress of the incident
  2. Abruptio placenta
  3. Uterine rupture
  4. Disseminated intravascular coagulopathy secondary to skin necrosis from thermal injury

Answer 1: C. The patient was working on a ceiling fan when he was electrocuted, which is concerning for electrocution with AC type current. The arrhythmia most closely associated with AC electricity is ventricular fibrillation (C). Commonly, they may also develop ventricular tachycardia, which was not an answer choice. Atrial fibrillation (Choice A), Torsades (Choice B) and supraventricular tachycardia (Choice D), are not commonly encountered as arrhythmias engendered by AC electricity.

Answer 2: A. Ventricular fibrillation is treated with immediate unsynchronized cardioversion (defibrillation). Synchronized cardioversion (B) is not the treatment of choice for ventricular fibrillation. Cardioversion with magnesium sulfate (C) is a treatment supported by several studies for the stabilization of atrial fibrillation with rapid ventricular response and would not be first-line in this scenario. Lidocaine (D) is no longer stipulated as an ACLS intervention per the 2010 guidelines established by the American Heart Association and is not the treatment of choice for ventricular fibrillation, as it may predispose to asystole.

Answer 3: C. The patient pictured above demonstrates both entry and exit wounds, raising suspicion for deep tissue involvement. The goal of treatment in these patients is to maintain a urine output of 1-2 ml/kg/hr. Many physicians usually begin estimating fluid needs with the Parkland Burn Formula, but due to the suspicion of deep tissue involvement, actual fluid requirements to achieve this urine output may overestimate what the formula establishes. Choice A is incorrect. A standard fluid bolus for severe dehydration would follow the 4-2-1 rule but may underestimate the fluid requirements in our patient. Choice B is incorrect. Albumin is a colloid and has not demonstrated appreciable benefits over crystalloids, which are currently the standard of care and considerably more cost efficient than colloids. Additionally, the question stem does not make any suggestion of the patient being hypotensive. Choice D is incorrect. Fluid resuscitation should not be postponed in any patient with burns of this severity and should be one of the primary focuses of management of such.

Answer 4: B. The most common complication of pregnant women who are struck by lightning is placental abruption, which should be immediately suspected in this patient. Placental abruption is characteristically a painful bloody discharge from the vagina, as opposed to placenta previa, which is typically painless. Choice A is incorrect. Pre-term labor is definitely a possibility in this situation, as it is in any stressful situation, but to diagnose pre-term labor, information regarding contraction timing and intervals must also be evaluated. Choice C is incorrect. Uterine rupture usually presents with visible abdominopelvic deformities and fetal ascent with profuse vaginal bleeding which were not described in the question stem. Choice D is incorrect. Disseminated intravascular coagulation has been described as the most common coagulation disorder in electrical injuries as a result of tissue necrosis caused by burns, but if this were the cause of vaginal bleeding, other sites would also be bleeding due to its systemic nature.

References:

  1. Tintinalli et al. Tintinalli's Emergency Medicine, 7th ed., 2011 Chapter 212, Pg. 1386-1394.
  2. American Heart Association 2010 Guide for Emergency Cardiovascular Care, 2010 Pg. 5-9, 38.

Hypocalcemia
Casey Grover, MD
Stanford/Kaiser Emergency Medicine

A 17 year-old female with a history of total thyroidectomy was sent to the emergency department (ED) for an abnormal lab study. The patient reported a previous history of electrolyte problems with which she felt "twitchy," yet reported no symptoms during this ED evaluation. A blood pressure cuff was placed on the patient's right arm and inflated to a pressure above the patient's systolic blood pressure. After approximately 2 minutes, the patient's right hand developed a contracted position (Figure 1, left panel). Within seconds of release of the cuff, the patient's hand returned to a normal position (Figure 2, right panel).

AAEM: Hypocalcemia

Diagnosis:
Hypocalcemia. A serum calcium obtained in the ED was 6.9, with an ionized calcium of 0.85. The patient was given two grams of intravenous calcium gluconate and was discharged home to follow up with her endocrinologist the following morning.

The development of carpal spasm in patients with hypocalcemia after placement of a blood pressure cuff on the arm that is inflated above systolic pressure is known as Trousseau's sign. The spasm causes the hand to develop a characteristic position, as in this patient, within 3 minutes of cuff inflation. Hypocalcemia is most commonly from low vitamin D levels, hypoparathyroidism, small intestinal disease with malabsorption and adverse medication effects. It is also a well-recognized complication after thyroid and parathyroid surgery, as in this patient. Common symptoms include muscular spasm, tingling and numbness. Severely affected patients may develop seizures and cardiac dysrhythmias.

References

  1. Granja et al. Improved survival with therapeutic hypothermia after cardiac arrest with cold saline and surfacing cooling: keep it simple. Emerg Med Int, 2011 April; 2011. Epub.
  2. Nichol et al. Regional systems of care for out-of-hospital cardiac arrest: a policy statement from the American Heart Association. Circulation. 2010;121(5):709–29.
  3. Neumar et al. Post-cardiac arrest syndrome: epidemiology, pathophysiology, treatment, and prognostication. A consensus statement from the International Liaison Committee on Resuscitation. Circulation. 2008;118(23):2452–83.

Are Antibiotics Necessary for Patients with Uncomplicated Abscesses?
Mary Calderone, MS2
Michael Pulia, MD FAAEM
Loyola University Chicago, Stritch School of Medicine

Patients frequently present to the ED with skin and soft tissue infections (SSTIs), typically cellulitis and abscess. Incision and drainage (I&D) remains the standard of care for patients with uncomplicated abscesses, but controversy still exists over the necessity of subsequent antibiotic therapy given the prevalence of CA-MRSA, estimated to cause 50-81% of SSTIs. Traditionally, most strains of CA-MRSA isolated from SSTIs are susceptible to Trimethoprim/sulfamethoxazole (TMP-SMX), consequently the most widely used antibiotic for such cases.

A randomized controlled trial by Schmitz et al. (2010) compared TMP-SMX vs. placebo for adult patients with uncomplicated skin abscesses. The study found a statistically similar incidence of treatment failure in patients receiving TMP-SMX (15/88; 17%) versus placebo (27/102; 26%), a difference of 9%. A reduction in new lesions in the antibiotic vs. placebo group was also noted, a difference of 19%. Based on the results, Schmitz et al. concluded that the addition of TMP-SMX to I&D did not decrease rates of failure by 15% or more by 7 days compared with placebo, but may decrease new lesion development within 30 days.

Although provocative, the study has garnered criticism. In an editorial response, Spellberg et al. (2011) argued that the point estimate and wide 95% CI of the difference in treatment failures precludes conclusions about the efficacy of antibacterial agents for the treatment of simple abscesses. In fact, the trend toward a reduction in treatment failures and recurrent lesions with TMP-SMX actually suggests its potentially substantial benefit. Spellberg et al. also warn against the dangers of inappropriately choosing a percent difference in treatment failures between the two groups by which to dismiss the utility of antibiotics. Given the prevalence of SSTIs in the U.S., a 9% difference still translates to 145,000 excess treatment failures per year, which lead to further complications such as worsening infection and costly repeat procedures.

A similar editorial by Joshua Seth Broder, MD, notes the minimal cost of oral TMP-SMX ($4 at national retail chains such as Wal-Mart and Kroger) and argues that the cost of preventing one case of treatment failure remains far lower than the copay that most insurance plans charge for a repeat ED visit. Spellberg et al. thus argue for studies to be powered to rule out a difference in treatment failure rates of less than 5% between patients in the antibiotic vs. placebo group. Dr. Broder also criticizes Schmitz et al. for failing to acknowledge that inadequate powering may prevent their study from demonstrating a statistically significant difference between the two treatment groups. Such a β error (failure to reject the null hypothesis that antibiotics and placebo are equivalent for treatment of cutaneous abscess) may encourage physicians to inadvertently harm patients by withholding effective therapies based on insufficient evidence claiming a lack of benefit.

Two ongoing NIH funded placebo-controlled trials of uncomplicated abscesses will hopefully result in an adequately powered comparison between outcomes in patients treated with active antibiotics vs. those only treated with I&D. Until then, clinicians must be cautious when deciding to withhold antibiotic therapy for patients presenting with uncomplicated abscesses.

References:

  1. Broder JS. Randomized Controlled Trials, Antibiotics and Cutaneous Abscesses: Has lack of Statistical Power Prevented Recognition of an Effective Therapy? Annals of Emergency Medicine. 2011; 57(2): 185.
  2. Schmitz GR, Bruner D, Pitotti R, et al. Randomized Controlled Trial of Trimethoprim-Sulfamethoxazole for Uncomplicated Skin Abscesses in Patients at Risk for Community-Associated Methicillin-Resistant Staphylococcus aureus infection. Annals of Emergency Medicine. 2010; 56(3):283-287.
  3. Spellberg B, et al. To Treat or Not To treat: Adjunctive antibiotics for uncomplicated abscesses. Annals of Emergency Medicine. 2011; 57(2):183-184.