Emergency Medicine: Pretest Flashcards
What is the best method of diagnosing corneal abrasions?
Slit-lamp examination by observing fluorescein uptake in the area of the defect
Patients wearing contact lenses should be treated with topical antibiotics with antipseudomonal coverage.
Any patient presenting to the emergency department in the second or third trimester of pregnancy with bleeding should have ultrasound performed before pelvic examination to rule out what?
Placenta previa
Placenta previa is a contraindication to digital examination of the cervix, as placental trauma from the examination itself can lead to prfuse vaginal bleeding.
What is the best method of diagnosing benign positional vertigo?
Dix-Hallpike maneuver
The maneuver involves having the patient go from sitting to a supine position with eyes open and head rotated to the affected side. The test is positive if the maneuver reproduces vertigo and the patient exhibits latent rotary nystagmus.
What intracompartmental pressure measured with a Stryker device is considered diagnostic of compartment syndrome?
> 30mmHg
The presence of a pulse does not rule out compartment syndrome. The only way to diagnose compartment syndrome is to measure intracompartmental pressure with a Stryker device.
Altered mental status, hyperthermia, and muscle rigidity make up the classic triad for what condition?
Neuroleptic malignant syndrome (NMS)
This is a rare, but fatal reaction commonly associated with the use of antipsychotics. The cornerstone of treatment is supportive care with rapid cooling, fluid and electrolyte repletion, and monitoring. Dantrolene, a nonspecific skeletal muscle relaxant, generally used in the treatment of malignant hyperthermia, is also effective for NMS.
Which street drug can cause significant hyponatremia?
3,4-Methylenedioxymethamphetamine (MDMA)
It is a potent stimulus for serotonin release which results in the excessive release of vasopressin (ADH). This combined with large free-water intake (increased thirst), and increased sodium loss from physical exertion (dancing) result in hyponatremia.
All patients with chest pain and shortness of breath should recieve what test?
Electrocardiogram (ECG)
It is a quick, noninvasive test that often provides substantive information.
What is the appropriate management of a patient who presents after exposing an eye to superglue?
Application of large amounts of erythromycin gel in the eye
This lubricates the eye and prevents the abrasive effect.
What is the first-line therapy for patients with stable supraventricular tachycardia?
Adenosine
It is safe and effective and has a short half-life. It blocks conduction at the atrioventricular node leading to a brief period of asystole, which can be very disconcerting to those recieving or administering the medication.
Which medication is notorious for causeing seizures that are refractory to standard therapy?
Isoniazid
Pyridoxine (vitamin B6) is the treatment of choice.
What has proven effective for both prophylaxis and treatment of acute mountain sickness?
Acetazolamide
Supplemental oxygen and a descent of 1500 to 3000 feet will reverse high-altitude sickness in most cases. Nausea and vomiting can also be treated symptomatically. Hyperbaric oxygen is indicated in severe cases.
What must happen for “flail chest” to occur?
Fracture of 3 or more adjacent ribs at two points
What is the most common cause of arrest in children?
Respiratory
What is the most useful diagnostic test in a patient suspected to have a spinal epidural abscess?
Magnetic resonance imaging (MRI)
Respiratory depression with apnea, interrupted by periods of agitation and combativeness (especially following attempts at intubation) are a distinctive feature of intoxication with which substance?
Gamma-hdroxybutyrate (GHB)
GHB is a natural neurotransmitter that induces sleep. It has been sold as a muscle builder (sleep increases release of growth hormone), a diet aid, and a sleep aid. Patients with GHB overdose generally have a decreased level of consciousness. In contrast to other sedative/hynotic overdoses, the level of consciousness tends to fluctuate quickly between agitation and depression.
Which organ is most commonly injured as a result of blunt abdominal trauma?
Spleen
In approximately 66% of cases, it is the only damaged intraperitoneal organ. The liver is the second most commonly injured organ.
Brown-Sequard syndrome (hemisection of the spinal cord) results in what symptoms?
- Ipsilateral motor paralysis
- Contralateral loss of pain and temperature
What is the treatment for post-lumbar puncture headache?
A blood patch
This is done by injecting an aliquot of the patient’s blood in a sterile fashion just external to the dura mater at the same interspace where the LP occurred.
Which toxic alcohol does not cause metabolic acidosis?
Isopropyl alcohol
This is because it is metabolized to acetone, a ketone, not an acid. Isopropyl alcohol intoxication is often remembered by “ketosis without acidosis.” Another unique finding is the presence of “pseudo renal failure” or isolated false elevation of creatinine with a normal BUN. This results from interference of acetone and acetoacetate by the colorimetric method used to measure the creatinine level.
What are the two main therapeutic agents in treating hepatic encephalopathy?
Lactulose and neomycin
Serum ammonia level is usually elevated in hepatic encephalopaty. Lactulose is a poorly absorbed sugar metabolized by colonic bacteria that traps ammonia and helps excrete it in the stool. Neomycin is a poorly absorbed aminoglycoside that is believed to act by reducing colonic bacteria responsible for producing ammonia.
Which medication is the most effective and most rapid means of reducing preload in a patient with congestive heart failure?
Nitroglycerin
Nitrates decrease myocardial preload and, to a lesser extent, afterload. Nitrates increase venous capacitance, including venous pooling, which decreases preload and myocardial oxygen demand. It is most beneficial when the patient who presents with congestive heart failure is also hypertensive. It is administered sublingually, intravenously, or transdermally. By contrast, Sodium Nitroprusside is is a mixed venous and arteriolar dilator; it reduces both pre- and afterload. It can be used in patients with acute pulmonary edema, but is typically reserved for individuals with a systolic blood pressure greater than 100 mmHg who fail to respond to adequate doses of standard preload reducers.
What causes miliaria rubra (heat rash)?
Sweat gland blockage and staphylococcal infection
What cause of chest pain occurs at rest and follows a circadian pattern, with most episodes occurring in the early hours of the morning?
Prinzmetal (Variant) angina
This is caused by focal coronary artery vasospasm.
1-2 weeks of fever, localized pain in the back, and progressive weakness is suggestive of what diagnosis?
Spinal epidural abscess
An elevated white blood cell count is also commonly seen. Magnetic resonance imaging is the most useful diagnostic test.
What is the most common cause of painful rectal bleeding in the first year of life and in adults?
Anal fissures
The following signs/symptoms are characteristic of which diagnosis?
- Eye pain
- Fever
- impaired eye motility
- Decreased visual acuity
- Proptosis
Orbital cellulitis
Staphylococcus aureus and Haemophilus influenzae are common etiologies. Mucormycosis must be considered in diabetics and immunocompromised patients.
What is the first test that should be used to diagnose ovarian torsion?
Doppler ultrasound
CT scan may be necessary if the doppler study is equivocal.
What is the preferred treatment for an ST-elevation myocardial infarction?
Primary percutaneous intervention (I.E. angioplasty or stent)
It has been shown to improve long-term mortality over thrombolytic therapy.
How does Central cord syndrome present?
Greater neurological deficits in the upper extremities compared to the lower extremities
In addition, patients with central cord syndrome usually have decreased rectal sphincter tone and patchy, unpredictable sensory deficits.
What kind of crystals are found in pseudogout?
Calcium pyrophosphate crystals
The synovial fluid will reveal rhomboid-shaped crystals that are weakly positively birefringent under polarized light.
What is the best method of managing intussusception?
Air enema
This is both diagnostic and therapeutic.
The following signs/symptoms are characteristic of which diagnosis?
- Eye pain
- Blepharospasm (any abnormal contraction or twitch of the eyelid)
- Tearing
- Photophobia
- Foreign body sensation in eye
- Injected eye
- Punctuate lesions on corneal examination
- Decreased visual acuity
Ultraviolet keratitis (snow blindness)
This is essentially a radiation burn when an individual comes in close contact with an ultraviolet-ray-containing light source (Sun lamp, tanning bed, high altitude). Patients usually present 6-10 hours after exposure.
What is the mainstay of diabetic ketoacidosis management?
Aggressive fluid resuscitation and insulin therapy
Which kind of fracture occurs when the head is thrown into extreme hyperextension because of abrupt deceleration?
Hangman’s fracture (traumatic spondylolysis of C2)
This is characterized by bilateral fractures of the pedicles. Today the most common cause of a hangman’s fracture is the result of head-on automobile collisions.
What disease presents as a prodrome of 1-2 days of mild headache and myalgias, followed by high fever, chills, multiple rigors, and the following associated symptoms?
- Pulmonary: Cough, dyspnea, chest pain, hemoptysis
- Gastrointestinal: Nausea, vomiting, diarrhea, anorexia
- Neurological: Headache, altered mental status
Legionnaires disease
This is caused by Legoinella pneumophila, an intracellular organsim that lives in aquatic environments.
What is the best method of diagnosing multiple sclerosis (MS)?
Magnetic resonance imaging (MRI)
Demyelinating MS lesions are often well demonstrated on MRI but cannot be visualized on computed tomography (CT).
What is the most common pathogen responsible for causing necrotizing otitis externa?
Pseudomonas aeruginosa
This is an uncommon complication of otitis externa that occurs primarily in adult diabetics and other immunocompromised individuals. It is associated with a high mortality rate.
Myxedema coma is a life-threatening complication of which condition?
Hypothyroidism
Mortality in myxedema coma approaches 20-50% even with appropriate management.
Which 5 drugs can be effectively administered via endotracheal tube?
- Naloxone
- Atropine
- Versed
- Epinephrine
- Lidocaine
This is remembered by the mnemonic NAVEL.
Supraventricular tachycardia that is refractory to vagal maneuvers should be treated with what?
Adenosine
This is a very short-acting AV nodal blocking medication.
A 90% chance of passage of a renal stone occurs when the stone is what size?
<4cm
4-6mm stones pass 50% of the time. >6mm stones pas 10% of the time.
A transvaginal ultrasound can typically identify a gestational sac when the beta-hCG level is greater than what level?
1000mIU/mL
It can identify the yolk sac when the beta-hCG level is greater than 2500 mIU/mL.
Fracture of the neck of the 5th metacarpal is known as what?
Boxer’s fracture
It is one of the most common fractures of the hand and usually occurs from a direct impact to the hand (I.E. a punch with a closed fist).
What is the treatment of choice for miliaria rubra (heat rash)?
The antibiotic Chlorhexidine
This should be used in the acute phase. Salicylic acid may also be used to assist in desquamation but should not be used on large areas because of possible salicylate intoxication.
What should be given to contact lens-wearing patients with corneal abrasions?
Antipseudomonal medication (I.E. Tobramycin or fluoroquinolone drops)
It is important to distinguish corneal abrasions from corneal ulcers. Ulcers are deeper infections of the cornea that develop from corneal epithelial defects (I.E. abrasions). Contact lens wearers are also at high risk for corneal ulcers. The hallmark of a corneal ulcer is a shaggy, white infiltrate within the corneal epithelial defect.
In addition to peaked T-waves, hyperkalemia can cause what two electrocardiogram (ECG) changes?
- Loss of P waves
- Widening of the QRS complex
Eventually the tracing assumes a sine-wave pattern, followed by ventricular fibrillation or asystole.
What is the hallmark of beta-blocker toxicity?
- Bradycardia
- Hypotension
- Cold extremities
- Low blood sugar
Onset of toxicity is usually within 4 hours of ingestion. Management consists of fluid resuscitation and atropine. Patients with significant toxicity should recieve glucagon.
What is the initial treatment for acute pancreatitis?
Supportive: bowel rest, fluid resuscitation, and analgesia
90% of patients recover without complications. Surgery is reserved for complications of alcoholic pancreatitis, such as pseudocysts, phlegmons, and abscesses.
A fundoscopic examination that reveals a macular cherry-red spot with a pale retina and less pronounced arteries is diagnostic of what condition?
Central retinal artery occlusion
This is commonly caused by emboli, thrombi, vasculitis, or trauma. Treatment aims to dislodge the clot from the main artery to one of its branches and includes digital massage, vasodilation, and lowering intraocular pressure.
What causes Horner syndrome?
Interrupted sympathetic nerve supply to the eye
Unilateral findings of ptosis, miosis, and anhidrosis are seen.
When should blood products be administered in a trauma patient?
When vital signs only transiently improve or remain unstable despite resuscitation with 2-3 L of crystalloid fluid
If there is obvious major blood loss and the patient is unstable, blood transfusion should be started concomitantly with crystalloid administration.
The following findings are consistent with which diagnosis?
- Muscle weakness
- Hyporeflexia
- Intestinal ileus
- Respiratory paralysis
- Electrocardiogram (ECG) changes: Flattened T waves, presence of U waves, and prolonged QT and PR intervals
Hypokalemia
Potassium deficiency results in hyperpolarization of the cell membrane.
How does the Prehn sign help differentiate between testicular torsion and epididymitis?
The pain from epididymitis is relieved by physically lifting the testicle, but the pain from testicular torsion is not
Transverse fracture of the distal radial metaphysis, which is dorsally displaced and angulated is called what?
Colles fracture
This is the most common wrist fracture seen in adults.
What is the most common site of intracranial cerebral artery thrombosis?
Middle cerebral artery
Clinical findings can include contralateral hemiplegia, hemianesthesia, and homonymous hemianopsia. The upper extremity deficit is usually more severe than the lower-extremity deficit. Aphasia occurs if the dominant hemisphere is involved.
What agent is most commonly used for rate control in the emergency department for a patient with stable atrial fibrillation?
Diltiazem
This is a calcium channel blocker with excellent AV nodal blocking effects. Amiodarone is also used for rate control in atrial fibrillation; however, it is not a first-line agent and is recommended to be used selectively in patients with low left ventricular ejection fraction.
Different degrees of paralysis and loss of pain and temperature sensation in the setting of intack position, touch, and vibratory sensation are characteristic of what?
Anterior cord syndrome
The hallmark is the preservation of the posterior columns, maintaining position, touch, and vibratory sensation.
What is the treatment for benign positional vertigo?
Antiemetics, antihistamines, and Epley maneuver (a series of head and body turns that reposition the canalith)
What has priority over all other aspects of resuscitation in the critically ill or injured patient?
Airway assessment and management
Exposure to rust removing agents containing hydroflouric acid (HF) should be managed how?
Calcium gluconate gel and electrocardiogram monitoring
Fluorid avidly binds to available cations such as calcium and magnesium, thereby causing cell death. Profound hypocalcemia has been demonstrated in HF exposure.
What symptoms are characteristic of the anticholinergic toxidrome?
Delirium, mumbling speech, tachycardia, elevated temperature, flushed face, dry mucous membranes and skin, dilated pupils, and hypoactive bowel sounds.
This can be remembered by the phrase “Blind as a bat (mydriasis), red as a beet (flushed skin), hot as a hare (hyperthermia due to lack of sweating), dry as a bone (dry mucous membranes), and mad as a hatter (mental status change)”.
What condition is described as a potentially life-threatening cellulitis of the connective tissue of the floor of the mouth and neck that begins in the submandibular space and is commonly caused by an infected or recently extracted tooth?
Ludwig angina
The most common physical findings are bilateral submandibular swelling and tongue protrusion or elevation.
What is the fastest method of lowering intracranial pressure?
Hyperventilation
The onset of action is within 30 seconds.
What medication is considered first-line in treating hemodynamically stable ventricular dysrhythmias?
Amiodarone
Other commonly used medications include procainamide and lidocaine. Unstable arrhythmias require cardioversion.
Which medication was shown with the strongest evidence in the ISIS-2 trial to independently reduce mortality in patients with and acute myocardial infarction?
Aspirin
This should be administered early to all patients suspected of have an acute coronary syndrome, unless there is a contraindication.
What are some of the early and late symptoms of acute mountain sickness?
- Early: Nausea, vomiting, headache, and anorexia (symptoms of an acute viral syndrome)
- Late: Peripheral edema, oliguria, retinal hemorrhages, and finally high-altitude pulmonary or cerebral edema.
What is the first-line treatment for a stable patient with supraventricular tacchycardia?
Vagal maneuvers to slow conduction and prolong the refractory period in the AV node
This can be accomplished by asking the patient to bear down as if they are having a bowel movement and hold the strain for at least 10 seconds. If vagal maneuvers fail, the next step is giving adenosine.
Cardiac contusion most commonly occurs in what part of the heart?
Right ventricle
It is the most anterior aspect of the heart and closest to the sternum.
What medication class other than antipsychotics can cause dystonic reactions?
Antiemetics
Dystonic reactions may occur with the use of dopamine-blocking agents. They respond almost immediately to administration of diphenhydramine (Benadryl).
What 3 criteria qualify an effusion as exudative?
- LDH greater than 200 units
- Fluid-to-blood LDH ratio greater than 0.6
- Fluid-to-blood protein ratio greater than 0.5
What drug can be given to decrease runs of torsades des pointes?
Magnesium sulfate
An isolated fracture of the shaft of the ulna is called what?
Nightstick fracture
This can occur after a direct blow to the ulna and usually occurs when an individual raises his or her forearm up to protect their face from a blow.
What differentiates bacterial from fungal meningitis on examination of cerebrospinal fluid?
- Bacterial meningitis > 1000 white blood cells (WBCs), majority polymorphonucleur leukocytes, gram stain positive
- Fungal meningitis < 500 WBCs, majority monocytes, gram stain negative
The diaphram is innervated by the phrenic nerve, which originates from the spinal cord at what level?
C3-C4
The intercostal muscles of the rib cage are supplied by nerves that originate in the thoracic spine. Therefore, abdominal breathing in the absence of thoracic breathing indicates an injury below C4.
What 3 medications should be given to a patient with an anaphylactice reaction to an allergen?
- Epinephrine
- Antihistamine (I.E. diphenhydramine, ranitidine)
- Corticosteroid (I.E. methylprednisolone)
Antihistamines block the action of the circulating histamines at target tissue receptors. Corticosteroids have an onset of action of 4-6 hours after administration, and therefore are of limited value in the acute setting, but should be given since giving them early may blunt to biphasic reaction of anaphylaxis.
