NEW! PEER IX QUESTIONS NOW AVAILABLE! PEER (Physician's Evaluation and Educational Review in Emergency Medicine) is ACEP's gold standard in self-assessment and educational review. These questions are from PEER IX, which made its print debut in June 2017. To order PEER IX, go to to www.acep.org/bookstore.
- A 61-year-old woman presents with vertigo. She says it starts every time she moves her head. She has no hearing changes or tinnitus and no previous medical problems. Her blood pressure is 178/85; there are no neurologic deficits. Bedside positional testing demonstrates nystagmus with a long latency and transient duration; it is suppressible with repeated testing. What is the most likely diagnosis?
A. Benign paroxysmal positional vertigo
B. Meniere disease
C. Transient ischemic attack
D. Vertebral basilar artery insufficiency
- A 56-year-old man presents by ambulance, unresponsive and intubated, with stable vital signs. Paramedics report that he collapsed in a mall, and bystanders performed CPR and used an AED. “Shock advised” was noted on the AED, and bystanders said he showed signs of life. En route, a 12-lead ECG demonstrated an inferior wall STEMI. A repeat ECG shows continued inferior STEMI. Which of the following strategies for using therapeutic hypothermia is appropriate for this patient in the emergency department?
A. Consider starting it after the STEMI has been definitively managed
B. Start it with a target temperature of approximately 34 °C (93.2 °F)
C. Withhold it because of the patient's ECG abnormality
D. Withhold it since it was not initiated in the prehospital setting
- Which of the following patients is at risk for health care–associated pneumonia?
A. Man with stable COPD who visits the clinic once monthly for 6 months
B. Nurse practitioner who recently underwent outpatient knee arthroscopy
C. Paramedic in an urban service area who is healthy but working extra shifts
D. Woman with end-stage renal disease who goes to dialysis three times a week
- Which of the following aspects of the physical examination can best distinguish toxicity from an anticholinergic agent from that of a sympathomimetic agent?
A. Heart rate
- Which of the following statements about diagnosing spinal cord injury without radiographic abnormality is correct?
A. Axial loading is the most common mechanism
B. Computed tomography can reveal occult fracture
C. It is more likely in younger children than in older children
D. Spinal column tenderness is common in the lumbar area
- The correct answer is A, Benign paroxysmal positional vertigo.
Why is this the correct answer?
Benign paroxysmal positional vertigo (BPPV) is suggested by the onset of vertigo with changes in head position and by the age of the patient. More important, the physical examination confirms that this patient has peripheral vertigo; the nystagmus has a long latency, transient duration, and is fatigable with provocative testing (the Dix-Hallpike maneuver). Furthermore, it is not associated with any other neurologic deficits. This is distinct from central vertigo such as that caused by strokes and tumors, which tends to have nystagmus with a short latency, a sustained duration, is not fatigable, and tends to be accompanied by other cranial and peripheral nerve deficits. Benign paroxysmal positional vertigo is the most common cause of vertigo overall, accounting for approximately 40% of vertigo diagnoses and affecting roughly 10% of all adults by age 80 years. The incidence of BPPV increases with age, with peak onset between 50 and 60 years old. Women are more commonly affected than men, with almost a 3-to-1 female-to-male ratio. Osteoporosis, vitamin D deficiency, and a history of prior head trauma have all been associated with the development of BPPV. Benign paroxysmal positional vertigo is believed to be caused by loose calcium carbonate otoliths moving aberrantly within the semicircular canals of the inner ear, ultimately resulting in the false sensation of rotation. The posterior semicircular canal is most commonly affected and accounts for approximately 60% to 90% of all cases of BPPV. Patients usually present with brief episodes of vertigo, typically lasting less than 1 minute, that are provoked by head position changes such as rolling over in bed, getting out of bed, tilting the head upward to reach objects on high shelves, or tilting the head downward to tie shoes. Diagnosis can be made with a series of bedside maneuvers known as the Dix-Hallpike maneuver, which provokes directional and torsional nystagmus depending on the involved semicircular canal. If a Dix-Hallpike test is negative, a supine roll test may be performed to evaluate for lateral semicircular canal BPPV. The first-line treatment for BPPV is an attempt at repositioning the misplaced otolith with a procedure known as the Epley maneuver. This is effective in approximately 90% of cases. Pharmacologic treatments such as meclizine, ondansetron, and diazepam may be used to temper nausea and emesis in patients with BPPV but are not as effective as the Epley maneuver.Why are the other choices wrong?
Meniere disease is not likely because the patient lacks the typical aural symptoms. The classic triad for Meniere disease is intermittent episodes of ear fullness, tinnitus, and vertigo.A transient ischemic attack is an important consideration but is unlikely because of the lack of central signs on physical examination, including ataxia.Vertebral basilar artery insufficiency is an important consideration in the differential diagnosis, but this condition is unlikely because of the lack of central signs on physical examination. This diagnosis should always be considered in patients with vertigo that occurs when they look up (when raising the head compresses the vertebral artery).
- Peripheral vertigo is characterized by a lack of associated neurologic deficits and the demonstration of nystagmus with a long latency, transient duration, and fatigability.
- Benign paroxysmal positional vertigo is the most common cause of vertigo and has a peak onset in patients between 50 and 60 years old.
- The most widely accepted treatment is an otolith-repositioning procedure, most commonly the Epley maneuver.
Marx JA, Hockberger RS, Walls RM, eds. Rosen's Emergency Medicine: Concepts and Clinical Practice. 8th ed. St. Louis, MO: Elsevier; 2014: 162-169.e1.
Tintinalli JE, Stapczynski JS, Ma OJ, et al, eds. Tintinalli's Emergency Medicine: A Comprehensive Study Guide. 8th ed. New York, NY: McGraw-Hill; 2012: 1164-1173, 1921-1927.
- The correct answer is B, Start it with a target temperature of approximately 34 °C (93.2 °F).
Why is this the correct answer?
Therapeutic hypothermia, also referred to as induced hypothermia and more recently as targeted temperature management, can reduce the negative sequelae of cardiac arrest. Although the specific mechanism is unknown, therapeutic hypothermia likely involves the reduction in metabolic rate throughout the body as well as reduced electrical activity in the brain. This patient is a candidate because he had a shockable rhythm (either pulseless ventricular tachycardia or ventricular fibrillation) and was resuscitated in an out-of-hospital setting. The optimal timing of initiation of therapeutic hypothermia is broad, but initiation within the first 4 to 6 hours after resuscitation is best. Earlier applications are likely better. If clinically feasible, initiation as early as 15 to 30 minutes after resuscitation is appropriate. The target temperature for therapeutic hypothermia is 32 °C (89.6 °F) to 34 °C (93.2 °F), although temperatures as high as 36 °C (96.8 °F) have demonstrated benefit. Additional postresuscitation therapies, including advanced critical care and PCI, should be performed simultaneously with therapeutic hypothermia.
Why are the other choices wrong?
The presence of a STEMI by itself does not preclude the initiation of therapeutic hypothermia; in fact, STEMI and other ACS-related conditions are the most appropriate patient presentations for targeted temperature management.Another indication for therapeutic hypothermia is unresponsiveness or other very significant mental status abnormality. Resuscitated patients who are alert or medically unstable are not candidates. Patients experiencing noncardiogenic cardiac arrest are likely not candidates either. Again, the ECG finding of STEMI is a reason to start targeted temperature management, not withhold it.
Therapeutic hypothermia may be started in the prehospital setting, emergency department, cardiac catheterization laboratory, or intensive care unit; the patient's clinical situation as well as the capabilities of the particular location dictate the most appropriate time of initiation.
- Therapeutic hypothermia improves the chance of meaningful survival in patients resuscitated from cardiac arrest, particularly those resuscitated in the prehospital setting with shockable initial rhythms who are stable and remain unresponsive.
- Therapeutic hypothermia may be applied in a range of settings with minimal need for equipment.
Adams JG, Barton ED, Collings J, et al, eds. Emergency Medicine: Clinical Essentials. 2nd ed. Philadelphia, PA: Saunders; 2013: 55-71.
Callaway CW, Donnino MW, Fink EL, et al. Part 8: Post-cardiac arrest care: 2015 American Heart Association Guidelines update for cardiopulmonary resuscitation and emergency cardiovascular care. Circulation. 2015;132(18 Suppl 2): S465-S482.
- The correct answer is D, Woman with end-stage renal disease who goes to dialysis three times a week.
Why is this the correct answer?
Patients who regularly attend a dialysis clinic are considered at risk for health care-associated pneumonia (HCAP). Other risk factors include:
- Hospitalization within the past 3 months for 2 or more days
- Residence in a nursing home or long-term care facility
- Use of intravenous antibiotic therapy at home
Why are the other choices wrong?
Although the man with COPD has a chronic disease, his condition is stable, and he is not using immunocompromising medications, so he is not at risk to contract HCAP.
The nurse practitioner recently had surgery, but she was an outpatient. Because she did not stay in the hospital for 2 days or longer, she is not at risk either.
The paramedic most likely has been in and out of the emergency department and the hospital with sick patients multiple times, but because he has not been hospitalized, he does not meet the HCAP risk criteria.
- Extended care facility patients are at risk for health care-associated pneumonia.
- Hospitalization for 2 days or longer within the previous 90 days is a risk factor for health care-associated pneumonia.
- Treatments and medications that increase the risk for health care-associated pneumonia: chemotherapy, prolonged intravenous antibiotic therapy, dialysis and wound care provided in specialty clinics, immunocompromising medications, including steroids, immunomodulators, and TNF-alpha inhibitors.
Marx JA, Hockberger RS, Walls RM, eds. Rosen's Emergency Medicine: Concepts and Clinical Practice. 8th ed. St. Louis, MO: Elsevier; 2014: 978-987.
Tintinalli JE, Stapczynski JS, Ma OJ, et al, eds. Tintinalli's Emergency Medicine: A Comprehensive Study Guide. 8th ed. New York, NY: McGraw-Hill; 2012: 445-456.
- The correct answer is C, Skin.
Why is this the correct answer?
The skin is a helpful indicator to distinguish between these two conditions. Dry skin is expected with anticholinergic toxicity, and damp or sweaty skin is expected with sympathomimetic toxicity. An anticholinergic (more accurately, antimuscarinic) toxidrome can result from exposure to a variety of agents, including drugs (atropine, benztropine, diphenhydramine, various antipsychotics, tricyclic antidepressants) and plants (angel's trumpet, jimsonweed). The antimuscarinic state results from antagonism at central and peripheral nervous system muscarinic receptors. Manifestations include coma, delirium, diminished bowel sounds, dry and at times flushed skin, hyperthermia, mydriasis, tachycardia, urinary retention, and picking behavior. The sympathomimetic toxidrome also includes hyperthermia, mydriasis, and tachycardia, but the presence of diaphoresis can help distinguish it from the anticholinergic toxidrome. Hypertension is expected with ingestion of sympathomimetic agents, although it can also occur with antimuscarinics. Agitation and psychosis rather than delirium are also more typical with sympathomimetic agents than with antimuscarinic agents. Exposure to cocaine and phencyclidine can result in a sympathomimetic toxidrome. So can various amphetamines, including ecstasy (methylenedioxymethamphetamine [MDMA]), methamphetamine, and cathinones, recently sold in the United States as bath salts.
Why are the other choices wrong?Tachycardia is expected with both anticholinergic and sympathomimetic agents.
Mydriasis is expected with both anticholinergic and sympathomimetic agents.
Hyperthermia can occur with both anticholinergic and sympathomimetic agents.
Is it anticholinergic (antimuscarinic) toxicity or sympathomimetic toxicity?
Check the skin!
Anticholinergic (antimuscarinic) syndrome presents with dry skin:
- Other signs and symptoms include hyperthermia, mydriasis, tachycardia, delirium, coma, diminished bowel sounds, flushed skin (sometimes), urinary retention, picking
- Caused by exposure to drugs like atropine, benztropine, diphenhydramine, various antipsychotics, tricyclic antidepressants, and plants like angel's trumpet, jimson weed
Sympathomimetic syndrome presents with damp, sweaty skin:
- Other signs and symptoms include hyperthermia, mydriasis, tachycardia (sound familiar?), agitation, and psychosis (generally not delirium)
- Caused by exposure to cocaine, PCP, and amphetamines
- It's typical for patients to present with elevated temperature, dilated pupils, and a rapid heart rate with both antimuscarinic and sympathomimetic toxidromes.
- But dry skin (antimuscarinic) and diaphoresis (sympathomimetic) can help you distinguish between the two.
Hoffman RS, Howland MA, Lewin NA, et al. Goldfrank's Toxicologic Emergencies. 10th ed. New York, NY: McGraw-Hill; 2010:26-29.
Wolfson AB, Hendey GW, Ling LJ, et al, eds. Harwood-Nuss' Clinical Practice of Emergency Medicine. 6th ed. Philadelphia, PA: Lippincott, Williams & Wilkins; 2014: 1316.
- The correct answer is C, It is more likely in younger children than in older children.
Why is this the correct answer?Spinal cord injury without radiographic abnormality, or SCIWORA, is thought to occur more commonly in children than in adults because of the relative laxity of the ligaments of the spine in children. In addition, the large size of the head and the increased mobility of the cervical spine in younger children are thought to contribute to this phenomenon. For the same reasons, SCIWORA is more common in younger children than in older children and adults. It is also thought to occur from mechanisms such as spinal traction or even spinal ischemia due to stretching, attributed to this relative mobility. That being said, elderly patients are also at risk due to spinal stenosis or kyphosis. Central cord syndrome is a manifestation of SCIWORA. The term SCIWORA was coined and recognized before the use of MRI became more commonplace in emergency departments. With the use of MRI, more of these injuries are being identified as spinal cord contusion or ischemia. At one time, high-dose steroids were thought to have benefit in patients with spinal cord injuries. But this therapy has fallen out of favor. It is now generally accepted that the benefits are somewhat controversial and are outweighed by the risks.
Why are the other choices wrong?
The most common mechanism of injury in SCIWORA is flexion and extension. This can happen in motor vehicle crashes. Axial loading injuries, usually from falls, less commonly cause SCIWORA.
The definition of SCIWORA is a neurologic deficit that does not demonstrate any bony radiographic abnormality on plain films or CT scans. With increased use of MRI, these injuries are being identified more often as spinal contusions or ischemia or ligament-related injuries.
Because of its relative mobility and laxity, the cervical spine is the most common location of SCIWORA. It is least commonly seen in the lumbar spine.
- SCIWORA is more common in children than adults, although elderly persons can be affected.
- SCIWORA occurs most commonly in the cervical spine.
- Flexion and extension are the most common mechanisms of injury in SCIWORA.
Marx JA, Hockberger RS, Walls RM, eds. Rosen's Emergency Medicine: Concepts and Clinical Practice. 8th ed. St. Louis, MO: Elsevier; 2014: 315, 326, 401-402.
Wolfson AB, Hendey GW, Ling LJ, et al, eds. Harwood-Nuss' Clinical Practice of Emergency Medicine. 6th ed. Philadelphia, PA: Lippincott, Williams & Wilkins; 2014: 1175, 1177, 1194-1195.