Provided by PEERprep for Physicians
PEERprep for Physicians is ACEP's gold standard in self-assessment and educational review. Order PEERprep at acep.org/peerprep.
1. A 69-year-old woman presents with 2 days of right upper quadrant pain. Her vital signs include BP 100/85, P 114, R 22, and T 39.3°C (102.7°F); she has a positive Murphy sign and scleral icterus. Ultrasound reveals a common bile duct diameter of 14 mm. Which intervention is the definitive management for this patient's condition?
A. Endoscopic retrograde cholangiopancreatography
B. Intravenous antibiotic therapy
C. Intravenous fluid bolus
D. Oral antibiotics and GI follow-up
The correct answer is A, Endoscopic retrograde cholangiopancreatography.
Why is this the correct answer?
This patient has acute ascending cholangitis, which is often accompanied by bacteremia and septic shock. This is a surgical emergency that requires stabilization of hemodynamic abnormalities, initiation of broad-spectrum antibiotics, and surgical consultation. Definitive management involves early biliary tract decompression by endoscopic retrograde cholangiopancreatography (ERCP), percutaneous transhepatic cholangiography, or surgery. Studies have shown that the more severe the illness, the more critical the need for urgent biliary decompression using ERCP, which has better results than surgery.
Ascending cholangitis is most often caused by blockage of the common bile duct by a gallstone but can also develop secondary to malignancy or benign stricture. Ultrasonography can help detect intrahepatic ductal dilation as well as stones in the gallbladder or common bile duct. Patients with cholangitis often develop fever, chills, nausea, vomiting, and abdominal pain. The Charcot triad of symptoms includes right upper quadrant pain, fever, and jaundice. When these symptoms are also associated with hypotension and altered sensorium due to clinical signs of sepsis, they are described as the Reynolds pentad. Common laboratory abnormalities in acute ascending cholangitis include leukocytosis, hyperbilirubinemia, an elevated alkaline phosphatase level, and increased aminotransferase levels.
Why are the other choices wrong?
Although intravenous antibiotics are critical, the definitive management of ascending cholangitis is decompression of the biliary tract. Broad-spectrum antibiotic choices include piperacillin-tazobactam, imipenem, meropenem, ticarcillin-clavulanate, and ampicillin-sulbactam (with metronidazole).
Although this patient likely requires intravenous fluids and perhaps even vasopressors for hemodynamic stabilization, intravenous fluids alone are insufficient. If the diagnosis is unclear or there are other competing diagnoses, a CT scan of the abdomen and pelvis may be useful; however, cholangitis is the leading diagnosis in this case.
Oral antibiotics and outpatient follow-up are inappropriate. This patient requires urgent stabilization, intravenous antibiotics, and biliary tract decompression.
REFERENCES
Haines EJ, Thompson H. Liver and biliary tract disorders. In: Walls RM, Hockberger RS, Gausche-Hill M, et al, eds. Rosen's Emergency Medicine: Concepts and Clinical Practice. Vol 1. 10th ed. Elsevier; 2023:1058-1083.
Murray W, Carter KA, Stern E. Abdominal pain. In: Stone CK, Humphries RL, eds. CURRENT Diagnosis & Treatment: Emergency Medicine. 8th ed. McGraw-Hill Education; 2017:239-251.
Garber B, Wilson LD. Acute diseases of the biliary tract. In: Wolfson AB, Cloutier RL, Hendey GW, Ling LJ, Rosen CL, Schaider JJ, eds. Harwood-Nuss’ Clinical Practice of Emergency Medicine. 7th ed. Wolters Kluwer; 2021:580-585.
Wada K, Takada T, Kawarada Y, et al. Diagnostic criteria and severity assessment of acute cholangitis: Tokyo Guidelines. J Hepatobiliary Pancreat Surg. 2007 Jan 30;14:52-58. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2784515/
UpToDate article on diagnosing acute cholangitis, available in full with a subscription https://www.uptodate.com/contents/acute-cholangitis-clinical-manifestations-diagnosis-and-management
2. Which action is most appropriate in the treatment of an adult patient with diabetic ketoacidosis?
A. Administer sodium bicarbonate when the pH level is below 7.15
B. Delay insulin administration if the initial serum potassium level is below 3.3 mEq/L
C. Give a bolus of regular insulin at a dose of 0.01 units/kg body weight
D. Start 5% dextrose when the serum glucose level falls below 350 mg/dL
The correct answer is B, Delay insulin administration if the initial serum potassium level is below 3.3 mEq/L.
Why is this the correct answer?
The management of diabetic ketoacidosis (DKA) involves administering fluid, insulin, and potassium in addition to searching for and treating any precipitant, such as an infection. Initial hypokalemia is uncommon in DKA and represents extreme total body potassium depletion when present. In this situation, potassium administration should be initiated before insulin. A reasonable guideline is to delay insulin administration when the serum potassium level is below 3.3 mEq/L on presentation. Otherwise, as insulin and fluids are administered, hypokalemia worsens and predisposes patients to life-threatening respiratory paralysis and abnormal cardiac rhythms. Due to intracellular-to-extracellular shifting from acidosis and lack of insulin, most patients in DKA present with normal or slightly elevated serum potassium concentrations despite total-body depletion of potassium. In the absence of renal failure, it is appropriate to initiate potassium administration in DKA when the potassium level is 5.3 mEq/L or lower.
Why are the other choices wrong?
Sodium bicarbonate administration in DKA can delay a decrease in ketonemia and worsen hypokalemia. If administered, it is reserved for when the pH level is less than 6.90 (not 7.15). Sodium bicarbonate may also be considered in patients with life-threatening hyperkalemia.
Insulin boluses are not required in the management of DKA and have not demonstrated benefit over beginning with an insulin infusion. If used, a bolus dose of 0.10 to 0.14 units/kg (not 0.01 units/kg) is appropriate.
During DKA treatment, administration of dextrose may be needed when the serum glucose falls but significant ketoacidosis remains. Guidelines recommend dextrose administration when the serum glucose level is less than 200 mg/dL (not 350 mg/dL).
REFERENCES
Van Ness-Otunnu R, Hack JB. Hyperglycemic crisis. J Emerg Med. 2013 Nov;45(5):797-805.
Votey SR, Peters AL. Diabetes mellitus. In: Wolfson AB, Cloutier RL, Hendey GW, Ling LJ, Rosen CL, Schaider JJ, eds. Harwood-Nuss’ Clinical Practice of Emergency Medicine. 7th ed. Wolters Kluwer; 2021:1033-1042.
Nyce A, Byrne R, Lubkin CL, Chansky ME. Diabetic ketoacidosis. In: Tintinalli JE, Ma OJ, Yealy DM, et al, eds. Tintinalli’s Emergency Medicine: A Comprehensive Study Guide. 9th ed. McGraw-Hill Education; 2020:1433-1441.
Kitabchi AE, Umpierrez GE, Miles JM, Fisher JN. Hyperglycemic crises in adult patients with diabetes. Diabetes Care. 2009 Jul;32(7):1335-1343.
UpToDate article on treating diabetic ketoacidosis and hyperosmolar hyperglycemic state in adults, available in full with a subscription https://www.uptodate.com/contents/diabetic-ketoacidosis-and-hyperosmolar-hyperglycemic-state-in-adults-treatment
3. A 58-year-old man presents with low back pain that shoots down the back of his left leg. He is having difficulty with straining and prolonged sitting. With the patient lying supine, which physical examination finding is most specific for a diagnosis of herniated disc?
A. Raising the patient's straight left leg causes back pain
B. Raising the patient's straight left leg causes back pain and radiation of pain down the posterior left leg
C. Raising the patient's straight right leg causes back pain
D. Raising the patient's straight right leg causes back pain and radiation of pain down the posterior left leg
The correct answer is D, Raising the patient's straight right leg causes back pain and radiation of pain down the posterior left leg.
Why is this the correct answer?
Lumbar disc herniation is the most common cause of lumbar radiculopathy, also known as sciatica (a shooting or burning pain from the low back radiating down the posterior leg distal to the knee). The most common location of this herniation is at L5 to S1. Two tests used to evaluate these symptoms are the straight leg raise, which is performed by lifting the leg affected by the radiating pain, and the contralateral straight leg raise, which is performed on the opposite leg. The contralateral straight leg raise test is highly specific for disc herniation causing the nerve root compression that manifests as sciatica.
The straight leg raise test is highly sensitive but not very specific for disc herniation. In the straight leg raise, the patient lies on their back with the knee extended. The examiner then raises the affected leg up to 70°. Reproduction of low back pain that radiates down the posterior affected leg past the knee is considered a positive result, known as the Lasegue sign. Relief of pain when the knee is then flexed is known as the bowstring sign. This test has been shown to be sensitive but poorly specific for a disc herniation. Conversely, performing the same test on the unaffected leg — the contralateral straight leg raise test — and reproducing both the back pain and the radiation down the affected leg yields low sensitivity but close to 90% specificity for a sciatic disease.
Why are the other choices wrong?
This patient reports that his back pain radiates down his left leg. Reproducing the back pain only by raising his left leg is a negative result and is, therefore, nondiagnostic.
Raising the patient's left leg and reproducing both the back pain and the radiation represent a positive result that is very sensitive but nonspecific. Back pain and radiation while lifting the contralateral leg is more specific for disc herniation.
Regardless of which leg is raised, reproducing only the back pain is a negative test result. Radiation of the pain down the leg is required for a positive test result.
REFERENCES
Della-Giustina D, Dubin J. Neck and back pain. In: Tintinalli JE, Ma OJ, Yealy DM, et al, eds. Tintinalli’s Emergency Medicine: A Comprehensive Study Guide. 9th ed. McGraw-Hill Education; 2020:1881-1888.
UpToDate article on diagnosing acute lumbosacral radiculopathy, available in full with a subscription https://www.uptodate.com/contents/acute-lumbosacral-radiculopathy-pathophysiology-clinical-features-and-diagnosis
4. A 39-year-old man presents with intermittent chest pain, palpitations, sweating, and feelings of anxiety over the past 8 hours. He has a history of asthma, migraines, and panic attacks; he wants a prescription for a benzodiazepine. Which part of this patient presentation suggests a diagnosis other than a panic attack?
A. Asthma
B. Chest pain
C. Duration of symptoms
D. Migraine history
The correct answer is C, Duration of symptoms.
Why is this the correct answer?
Panic attacks are sudden-onset episodes of intense anxiety and fear. The episodes typically peak within 10 minutes and last up to 1 hour. This patient has been having symptoms for much longer than what is typical for a panic attack; this should prompt concern for another underlying medical problem. Further workup should be undertaken to rule out other serious pathologies, such as cardiac ischemia, aortic dissection, pulmonary embolism, or other life-threatening conditions. Various somatic and cognitive symptoms are associated with panic attacks, including paresthesias, shortness of breath, nausea, lightheadedness, inability to concentrate, and a fear of losing control or dying.
Why are the other choices wrong?
Asthma is one of many medical conditions associated with panic disorder. Others include interstitial cystitis, hypertension, hyperthyroidism, COPD, and irritable bowel syndrome. The nature of these associations has not been elucidated. Like chest pain, it is less compelling than the duration of symptoms.
Chest pain is frequently a symptom of panic attacks. Naturally, other serious medical causes of chest pain should be considered and, when possible, ruled out before a diagnosis of panic attack is made in the emergency department. However, chest pain is common enough that it raises the index of suspicion for an alternative diagnosis less than the duration of the patient's symptoms does.
Migraine headache has been associated with panic disorder. There is also a high rate of comorbidity between panic disorder and other psychiatric illnesses — particularly major depression, bipolar disorder, and other anxiety disorders, most commonly agoraphobia.
REFERENCES
American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders (DSM-5). 5th ed. American Psychiatric Association; 2013.
DeSelm TM. Mood and anxiety disorders. In: Tintinalli JE, Ma OJ, Yealy DM, et al, eds. Tintinalli’s Emergency Medicine: A Comprehensive Study Guide. 9th ed. McGraw-Hill Education; 2020:1946-1952.
UpToDate article on panic disorder in adults, available in full with a subscription https://www.uptodate.com/contents/panic-disorder-in-adults-epidemiology-clinical-manifestations-and-diagnosis
5. When obtaining a cystourethrogram in an adult patient with pelvic trauma, what volume of contrast medium must be instilled into the bladder to prevent a false-negative evaluation?
A. 200 mL
B. 400 mL
C. 600 mL
D. 800 mL
The correct answer is B, 400 mL.
Why is this the correct answer?
Using 400 mL of contrast material when obtaining a cystourethrogram can prevent a false-negative evaluation of the bladder. The indications for performing cystourethrography in the setting of pelvic trauma include the inability to void, blood at the meatus, a scrotal hematoma, perineal bruising, an unstable pelvic fracture, and a high-riding prostate. Each of these findings should prompt the physician to perform urethrography (eg, retrograde urethrogram) before cystography to confirm an intact urethra and assess for possible bladder injuries. Another indication can be penetrating trauma to the pelvis.
Imaging using either x-ray or fluoroscopy takes place after the infusion of contrast material into the urethra using a Toomey irrigator or a Foley catheter placed at the urethral meatus. After an intact urethra is confirmed, a Foley catheter is then inserted; 400 mL of contrast material is infused by connecting a 60-mL syringe to the catheter with the plunger removed and then allowing gravity to fill the bladder by lifting the syringe above the plane of the patient. Anteroposterior and lateral images of the pelvis should be evaluated for extravasation in all planes, especially superiorly and posteriorly. If urethral injury is found, placement of a suprapubic catheter may be indicated.
Why are the other choices wrong?
Using only 200 mL of contrast material can lead to a false-negative evaluation of the bladder. The correct amount of contrast material is 400 mL.
Using 600 mL of contrast material may overextend the bladder. The correct amount of contrast material is 400 mL.
Using 800 mL of contrast material is likely to overextend the bladder and can increase the extravasation if there is a bladder injury. The correct amount of contrast material is 400 mL.
REFERENCES
Davis JE, Silverman MA. Urologic procedures. In: Roberts JR, Custalow CB, Thomsen TW, et al, eds. Roberts and Hedges’ Clinical Procedures in Emergency Medicine and Acute Care. 7th ed. Elsevier; 2019:1150-1154.
Stubbs AM. Trauma to the flank and buttocks. In: Tintinalli JE, Ma OJ, Yealy DM, et al, eds. Tintinalli’s Emergency Medicine: A Comprehensive Study Guide. 9th ed. McGraw-Hill Education; 2020:1755-1757.
UpToDate article on traumatic and iatrogenic bladder injury, available in full with a subscription https://www.uptodate.com/contents/traumatic-and-iatrogenic-bladder-injury