Board Review Questions: April 2017

0

Provided by PEER VIII. 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 the latest edition of PEER VIIITo learn more about PEER VIII, or to order it, go to www.acep.org/bookstore.

  1. A 64-year-old man with a history of hypertension, diverticulosis, and remote abdominal aortic aneurysm repair presents with a 2-day history of black stools, abdominal discomfort, and low-grade fever. He is diaphoretic. Vital signs include blood pressure 72/46, pulse 138, and respiratory rate 24. Physical examination reveals a midline abdominal scar, diffuse abdominal tenderness, and bright red blood in his rectum. Two large-bore intravenous lines are placed, and fluid resuscitation is begun. What is the appropriate next step in management?
    A.     Obtain vascular surgery consultation
    B.     Order abdominal and pelvic CT scans and start intravenous antibiotics
    C.     Start nasogastric lavage and obtain endoscopy consultation
    D.     Start proton-pump inhibitor and octreotide infusion
  2. Which of the following antidepressants is most likely to cause QRS interval prolongation and convulsions in overdose?
    A.     Fluoxetine
    B.    Sertraline
    C.     Trazodone
    D.     Venlafaxine
  3. A mother brings in her 5-month-old son because his right leg does not look right. She points out a difference in the appearance of the skin around the right hip and a difference in the range of motion compared with the left. Clinical examination confirms these findings. The mother denies any history of trauma; she is the sole caretaker. The child is happy and playful during the examination. There are no rashes or markings on the skin, and the child is of normal height and weight. Additional examination is likely to reveal:
    A.     A definitive “clunk” with movement of the femoral head
    B.     Definitive radiographic evidence of bilateral hip abnormality
    C.     Hypertrophy of the gluteal muscles on the affected side
    D.     The definitive diagnosis based on skinfold asymmetry
    E.      Toxic synovitis
  4. The development of biphasic defibrillators affected intervention in ventricular fibrillation by:
    A.     Decreasing first shock success rates
    B.     Decreasing the number of shocks needed to defibrillate
    C.     Increasing the current applied to the myocardium
    D.     Increasing the effect of electrical current on cardiac myocytes
  5. A 23-year-old man presents with bilateral peripheral facial nerve paralysis. He says he has felt fatigued for the past 1 to 2 weeks. He is an avid hiker but denies any injury. He is not sexually active and has no significant social history. He has no other neurologic deficit. What is the most likely pathogen?
    A.     Borrelia burgdorferi
    B.     Herpesvirus
    C.     HIV
    D.     Rickettsia rickettsii

Answers

  1. The answer is A, Obtain vascular surgery consultation.
    (Marx, 1095-1100; Tintinalli, 543, 545-547)
    In an unstable patient with gastrointestinal bleeding who has a history of abdominal aortic aneurysm (AAA) repair, the appropriate action is to get an emergent surgery evaluation for operative intervention. An aortoenteric fistula (AEF) can be a primary complication of AAA before repair or, more commonly, a secondary complication occurring anytime after repair. The AEF typically begins to develop when the bowel is eroded by the aneurysm, resulting in local infection, abscess, or occasionally, a sentinel bleed from a local vessel in the bowel wall. Typically, massive bleeding from a duodenal fistula follows. However, bleeding can be acute or chronic, upper or lower, depending on the exact site and source. Aortoenteric fistula must be ruled out in any patient presenting with a newly diagnosed or repaired AAA and upper or lower gastrointestinal bleeding. Management depends on the patient’s hemodynamic stability. With overt shock, emergent surgical diagnosis and definitive repair are required. In patients whose conditions are stable, CT scanning often does not reveal the AEF directly but can identify the local infection accompanying fistula formation, as well as other possible diagnoses such as diverticular disease. Angiography can be used in patients whose conditions are stable, to diagnose AAA and AEF but has largely been replaced by ultrasonography and CT. Nasogastric lavage is helpful in identifying the location of bleeding and need for intervention with gastrointestinal bleeding but only delays definitive management in an unstable patient with AEF. Proton pump inhibitors and octreotide drips are important for suspected variceal bleeding but are not indicated for AEF.
  1. The answer is D, Venlafaxine.
    (Nelson, 1041, 1043-1044; Wolfson, 1510)
    Venlafaxine (marketed as Effexor) is a serotonin-norepinephrine reuptake inhibitor that, unlike many of the newer antidepressants, has sodium-channel blockade properties. Significant overdoses can manifest with QRS interval prolongation and convulsions. The presentation is similar to that of tricyclic antidepressant overdose, as is the treatment, with sodium bicarbonate and benzodiazepines, respectively. A variety of nonmonoamine oxidase inhibitor, nontricyclic antidepressant agents exist. They are referred to as newer antidepressants and have varying mechanisms of action. Some have selective serotonin reuptake activity (SSRIs), some with serotonin reuptake activity (SRIs) with other activity, and others with distinct mechanisms of action. The SSRIs (with brand names in parentheses for ease of reference) include citalopram (Celexa), escitalopram (Lexapro), fluoxetine (Prozac, Rapiflux, Sarafem, and others), fluvoxamine (Luvox), paroxetine (Paxil, Pexeva), and sertraline (Zoloft). Atypical (non-SSRI) antidepressants include bupropion (Aplenzin, Wellbutrin and marketed as Buproban and Zyban for smoking cessation), duloxetine (Cymbalta), mirtazapine (Remeron), trazodone (Desyrel, Oleptro), and venlafaxine (Effexor). Fortunately, most SSRIs and atypical antidepressants in overdose are not associated with significant toxicity. Exceptions include rare massive overdoses of almost all of the agents. Additionally, certain agents can occasionally cause certain manifestations that, although uncommon, must be kept in mind when managing an overdose with them. Citalopram is associated with convulsions and QT-interval prolongation. The main complication of bupropion overdoses that emergency physicians should be aware of is convulsions, which also occur with therapeutic use. With extended-release preparations, significant time delay in onset of convulsions is possible. Trazodone has alpha1 antagonist activity, and overdoses can manifest with peripheral vasodilation and resulting hypotension that typically responds to fluid administration. Both therapeutic use and overdose are also associated with priapism.
  1. The answer is A, A definitive “clunk” with movement of the femoral head.
    (Fleisher, 1004; Marx, 2257-2259)
    In a patient with developmental dysplasia of the hip (DDH), a positive Ortolani sign is a definitive “clunk” when the dislocated femoral head reduces into the acetabulum with movement. Clinical findings of DDH can include asymmetric skin folds noted in the groin, along the thighs, or below the buttock; one-third of patients have skinfold asymmetry, but this finding is not specific for the disorder. Shortening of the leg on the affected side with a reduced range of motion can also be noted. There is ultimately atrophy of the gluteal muscles on the affected side. To perform the Ortolani maneuver, the physician slightly abducts the patient’s hip and, with the index and middle fingers over the greater trochanter, pulls up on the thigh to reduce the hip dislocation. The abnormal finding is the perceptible relocation/dislocation by either feel or sound. The Barlow test is another diagnostic approach. The physician places a thumb on the patient’s inner thigh near the lesser trochanter and adducts the hip, applying downward pressure on the thigh with the thumb. This test is also called provocative: any abnormal movement of the femoral head and acetabulum is a positive finding. The Barlow and Ortolani tests are less effective in detecting instability of the hips in older pediatric patients. Radiography is not useful in a patient younger than 6 months because of the lack of ossification and the difficulty of interpreting the findings. Ultrasonography is best delayed in a newborn, as some conditions (such as laxity without dislocation) can be seen early in life and resolve without intervention by the time the infant is 4 to 6 weeks old.
  1. The answer is B, Decreasing the number of shocks needed to defibrillate.
    (Link, S708-S709; Roberts, 220, 229; Wolfson, 32)
    The advent of newer, biphasic defibrillators has resulted in an increased first shock success rate, less electrical current required, and reduced damage to cardiac cells. The biphasic waveforms are used to deliver current through the heart, reverse polarity, and return through the myocardium. Therefore, less energy is needed with biphasic technology to convert arrhythmias. Because the patient is in ventricular fibrillation for a shorter period of time, a decreased rate of postfibrillation rhythm disturbances can be expected. Biphasic defibrillators produce a waveform that flows back and forth between the electrodes as either a BTE (biphasic truncated exponential) waveform or biphasic rectilinear waveform. It is important for emergency physicians to be knowledgeable about the defibrillators available for their use, as the device-specific effective waveform determines the starting energy level for defibrillation. With a biphasic rectilinear waveform, 120 joules is appropriate; with a BTE waveform, 150 joules is a starting energy to terminate ventricular fibrillation. When the type is not known, the recommended starting energy is 200 joules.
  1. The answer is A, Borrelia burgdorferi.
    (Marx, 1382-1383; Wolfson, 784-786)
    The most common known cause of bilateral peripheral or seventh cranial nerve (the facial nerve) palsy is infection with Borrelia burgdorferi, the organism that causes Lyme disease. Patients who present with idiopathic facial nerve paralysis, also known as Bell palsy, should be asked about risk factors for Lyme disease. In particular, patients who present with bilateral peripheral seventh nerve palsy should be evaluated with serologic testing. Human immunodeficiency virus, infectious mononucleosis, and sarcoidosis are other known etiologies of bilateral facial nerve palsy. The most common etiology of Bell palsy, which typically presents with unilateral facial nerve palsy, is herpesvirus. Other etiologies include Lyme disease; other viral etiologies; bacterial etiologies such as Pseudomonas aeruginosa (the most common bacteria present in malignant otitis externa); trauma (the facial nerve is the most commonly injured cranial nerve); and tumor (typically a more insidious or relapsing/remitting onset). Rickettsia rickettsii is the bacteria known to cause Rocky Mountain spotted fever, which does not commonly cause cranial nerve abnormalities. Patients with Bell palsy typically present with symptoms of complete facial paralysis (which does not spare the forehead). Additional symptoms can include ear pain, hyperacusis (acute and often painful hearing), increased or decreased tearing, decreased sensation in the affected area, and an alteration in taste. Because motor function is impaired in Bell palsy (including the ability to fully close the eye on the affected side, often in conjunction with decreased tearing), patients are at risk for corneal abrasions. They should be evaluated for such and treated with patching and lubrication as needed to prevent abrasions at high-risk times, such as while sleeping. Currently accepted treatments include steroids such as prednisone and antiviral agents for presumptive herpe
Share.

Leave A Reply