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1) A 42-year-old woman is brought to the emergency department 45 minutes after being involved in a motor vehicle…
CT scan of the abdomen
- Young woman involved in a motor vehicle accident presents with severe abdominal pain, anemia, flank ecchymosis and gross hematuria, and therefore should have an abdominal CT scan to investigate for possible renal injury
- Key idea: CT imaging should be pursued if patient has (1) Concerning mechanism of injury (direct blow to the flank or (2) Concerning clinical findings (hematuria, flank pain, flank ecchymosis)
- Exploratory laparotomy would be appropriate in setting of hemodynamic instability or peritonitis (rebound/guarding)
2) A 57-year-old woman is undergoing elective endoscopic retrograde cholangiopancreatography with 20% benzocaine spray…
Intravenous administration of methylene blue
- Middle-aged woman who receives benzocaine and then becomes cyanotic with an extremely high PaO2 on ABG but a decreased O2 saturation with elevated methemoglobin levels, concerning for methemoglobinemia that should be treated with IV administration of methylene blue +/- vitamin C
- Key idea: Methemoglobinemia classically leads to an oxygen saturation gap (large difference between PaO2 on ABG and oxygen saturation with pulse oximetry) because although there is a lot of arterial oxygen, it is unable to bind to hemoglobin
- Common triggers of methemoglobinemia (oxidizing stress):
- Sulfa drugs
- Nitrate drugs
- Benzocaine
- Drinking unfiltered water in mountainous region (high levels of nitrites)
- 100% oxygen –> Treatment for cluster headache (recurrent nighttime headache with severe pain behind eye +/- lacrimation, rhinorrhea)
- Hyperbaric oxygen therapy –> Carbon monoxide poisoning (headache, cherry red skin, indoor heater or house fire)
- Exchange transfusion –> Often used in setting of antibody-mediated diseases (Guillain Barre, Myasthenia Gravis, etc.)
3) A 51-year-old man comes to the physician 10 days after discovering a nontender mass in his neck. His father…
Medullary carcinoma
- Middle-aged man with strong family history of thyroid cancer presents with a firm thyroid nodule, concerning for medullary thyroid cancer in the setting of MEN syndrome
- MEN 1 –> 3 P’s –> Parathyroid adenoma, Pituitary tumor (prolactinoma, etc.), Pancreataic tumor (Zollinger-Ellison syndrome, VIPoma, etc.)
- MEN 2A –> 2 P’s –> Parathyroid adenoma, Pheochromocytoma, Medullary thyroid cancer
- MEN 2B –> 1 P –> Pheochromocytoma, Medullary thyroid cancer, Marfanoid habitus with mucosal neuromas
- Key idea: Remember that parathyroid adenoma is MEN 1 and MEN 2A whereas pheochromocytoma is 2A and 2B because parathyroid comes before pheochromocytoma alphabetically
4) One week after undergoing laparotomy for a gunshot wound to the right upper quadrant of the abdomen…
Hematobilia
- Young man with recent liver surgery in setting of gunshot wound to RUQ presents with increasing jaundice and hematemesis with upper endoscopy demonstrating clots and blood in the duodenum, suggestive of hematobilia (blood accumulation in the biliary system leading to cholestatic liver injury)
- Key idea: Bile duct dumps into the duodenum, which could explain presence of duodenal clots despite no visualized area of active bleeding
- LFT abnormalities can generally be broken down into:
- Hepatocellular (ALT/AST increase >>> Alk phos and bilirubin increase)
- Toxins (acetaminophen, alcohol, etc.)
- Ischemia (shock liver in setting of sepsis/hypovolemia)
- Viruses (hepatitis A-E, CMV, VZV, etc.)
- Other (autoimmune hepatitis, Wilson disease, etc.)
- Cholestatic (Alk phos and direct bilirubin increase >> ALT/AST increase)
- Choledocholithiasis +/- acute cholangitis
- Pancreatic cancer (head) or cholangiocarcinoma
- Primary sclerosing cholangitis
- Primary biliary cirrhosis
- Hepatocellular (ALT/AST increase >>> Alk phos and bilirubin increase)
5) A 55-year-old man comes to the physician’s office because of claudication. He smokes two packs of cigarettes per day…
- Middle-aged man with significant atherosclerotic risk factors presents with claudication with ankle-brachial indices < 0.90 consistent with peripheral artery disease –> Best initial management is lifestyle changes and exercise program (to improve local circulation)
- If non-invasive therapies and lifestyle changes are inefficient –> Balloon angioplasty or bypass procedure
- Key idea: In setting of suspected claudication, always consider possible pseudoclaudication in setting of spinal stenosis (patient complains of pain in legs with walking that improves with leaning forward)
6) A previously healthy 6-year-old girl is admitted to the hospital because of a 2-day history of fever and progressive left…
Surgical incision and drainage
- Young girl presenting with severe hip pain (resists motion, inability to bear weight) and fever with arthrocentesis showing WBC count >100,000, concerning for septic arthritis –> Management includes emergent surgical incision/drainage + Antibiotics
- Key idea: Severe hip pain (resisting motion, inability to bear weight) should make you consider avascular necrosis (corticosteroids, alcoholism, sickle cell disease, etc.) and septic arthritis (febrile)
- Colchicine or NSAID therapy –> Acute gout (inflammatory arthritis of knee or big toe in middle-aged patient)
7) A 36-year-old woman with type 1 diabetes mellitus has fever and flank pain. Her temperature is 39 C (102.2 F)…
Perinephric abscess
- Young woman with T1 diabetes (relatively immunocompromised) presents with fever and flank pain with leukocytosis and positive urine culture concerning for pyelonephritis. However, despite 10 days of IV antibiotics she continues to be febrile, concerning for possible complication such as a perinephric abscess (which requires drainage for source control and will often be refractory to antibiotics)
- Key idea: WBC casts are seen both in pyelonephritis and acute interstitial nephritis (fever + rash + AKI in patient started on a new drug)
8) While undergoing a splenectomy for immune thrombocytopenic purpura, a 49-year-old man aspirates during a difficult…
Volume of aspirated fluid
- Key idea: Increased volume of aspirate –> Increased bacterial inoculum –> Harder for immune system to clear brewing infection
- Differences between aspiration pneumonitis and aspiration pneumonia:
- Aspiration pneumonitis: Lung inflammation due to direct tissue injury from aspirated gastric acid that presents hours after aspiration event with dyspnea, cough and CXR infiltrate that resolves without antibiotics (Tx: Supportive)
- Aspiration pneumonia: Lung infection due to aspirated microbes that presents days after aspiration event with dyspnea/cough and inflammatory signs (fever, leukocytosis, etc.) and Right lower lobe infiltrate
- Tx: Clindamycin (covers anaerobes above diaphragm) or Augmentin (covers anaerobes in mouth, best choice for human bite injuries)
9) A 66-year-old man with unresectable squamous cell lung cancer has the acute onset of severe shortness of breath…
Thoracentesis
- Elderly man with squamous cell lung cancer presents with acute shortness of breath and unilateral pleural effusion, who should receive a therapeutic thoracentesis to improve symptoms
- Key idea: Patients on hospice should generally not have heroic/complex interventions (open pleurodesis, etc.) or interventions to prolong life (radiation therapy), but should definitely have simple interventions performed to reduce symptoms or improve quality of life (thoracentesis to decrease dyspnea, pain medications, etc.)
- Key idea: Hospice care generally reserved for patients who have are expected to pass away within 6 months and would like to forego interventions to prolong life with a transition to comfort care
10) An 8-year-old girl has had migrating polyarthralgia and fever for 4 days. She appears ill. Examination shows…
Mitral regurgitation
- Young girl presents with arthritis, rash and a new murmur (concerning for acute rheumatic fever), with a holosystolic apical murmur radiating to the axilla which is consistent with the murmur of mitral regurgitation
- Key idea: Rheumatic fever often seen following strep pharyngitis and leads to JONES criteria:
- Joints (polyarthritis)
- O (heart-shaped) –> pericarditis, myocarditis, endocarditis
- subcutaneous Nodules
- Erythema marginatum
- Sydenham chorea
- Aortic stenosis –> Systolic ejection murmur at R 2nd intercostal space that radiates to carotids
- Tetralogy of Fallot –> VSD murmur (holosystolic murmur at left lower sternal border) and Pulmonic stenosis murmur (systolic ejection murmur at left second intercostal space that increases with inspiration)
- Tricuspid regurgitation –> Holosystolic murmur at left lower sternal border that increases with inspiration
11) Thirty minutes after undergoing a radical gastrectomy for gastric carcinoma, a 67-year-old woman has an oxygen saturation…
Alveolar hypoventilation
- Elderly women who is 30 minutes post-op from a gastrectomy hand has hypoxia with
- A-a gradient = PAO2 – PaO2 = 59 – 56 = 3 < 21 --> Normal A-a gradient –> Hypoventilation
- PAO2 = 150 – (PaCO2 / 0.8) = 150 – (73/0.8) = 150 – 91 = 59
- PaO2 = From ABG = 56
- A-a gradient cutoff = 4 + (age/4) = 4 + (67/4) = 4 + 17 = 21
- Key idea: A-a gradient should be calculated to determine whether hypoxia is due to hypoventilation (normal A-a gradient) or V/Q mismatch (increased A-a gradient), but if pressed for time look at the degree to which patient is retaining CO2, with increased CO2 retention pointing towards hypoventilation
- Note: The calculations above are assuming the patient is receiving room air
- Dead space –> Ventilation without perfusion (pulmonary embolism classic example)
- Shunt –> Perfusion without ventilation (pneumothorax, pneumonia, etc.)
12) A previously healthy 27-year-old primigravid woman at 28 weeks’ gestation is admitted to the hospital 2 days after the…
Acute cholecystitis
- Young woman at 28 weeks gestation presents with RUQ pain and fever with voluntary rebound and is found to have leukocytosis and mild cholestatic LFT abnormality, concerning for acute cholecystitis
- Note: Acute cholecystitis should NOT technically lead to a cholestatic liver injury given that the disease is isolated to the cystic duct and gallbladder
- Key idea: Gallbladder disease seen at higher rates among pregnant woman because stones are more likely to be formed because increased estrogen leads to increased cholesterol production and progesterone inhibits bile secretion (stasis –> more stone production)
- Placental abruption –> Painful 3rd trimester bleeding
- Acute appendicitis –> RLQ pain without LFT abnormalities
- Fitz-Hugh-Curtis syndrome –> Pelvic inflammatory disease (fever and adnexal tenderness +/- cervical motion tenderness) that spreads to the liver
- Acute fatty liver of pregnancy –> 3rd trimester patient who presents with fulminant liver failure (hypoglycemia, thrombocytopenia, hyperbilirubinemia, transaminitis and DIC)
13) A 16-year-old girl is brought to the emergency department after being stabbed in the anterior neck 30 minutes ago…
Endotracheal intubation
- Key idea: For all emergent presentations, the first step is to ensure ABC –> Airway, Breathing and Circulation
- Indications for endotracheal intubation:
- Expanding hematoma, emphysema or edema in oral cavity or neck
- Glasgow-Coma scale of 8 or less (8 –> intub-8) [inability to protect airway]
- Severe inhalation injury (house fire, ash on face/mouth)
- Breathing is noisy (stridor) or patient is gurgling
- Indications for cricothyroidotomy:
- Same indications as endotracheal intubation except normal intubation not possible due to:
- Inability to intubate or ventilate
- Massive facial/nasal trauma
- Same indications as endotracheal intubation except normal intubation not possible due to:
14) A 67-year-old man comes to the physician because of a lesion on the left ear for 2 years. The lesion has gradually…
Basal cell carcinoma
- Elderly white man with significant occupational sun exposure presents with enlarging ulcerated lesion on a sun-exposed surface, with the lesion having central ulceration with rolled borders, concerning for basal cell carcinoma
- Actinic keratosis –> Rough scaly papule over sun-exposed surface (precursor to SCC)
- Keratoacanthoma –> Dome-shaped nodule with central keratotic debris, type of SCC
- Melanoma –> Pigmented lesion that is asymmetric with unclear borders, multiple colors, a diameter > 6 mm, and is evolving
15) A 37-year-old woman is scheduled for operative treatment of an umbilical hernia with incarcerated omentum under general…
Close the operative site and discuss further treatment with the patient when she awakens
- Key idea: When a non life-threatening issue is discovered incidentally during surgery, you need to discuss the finding and next best steps with the patient before proceeding both to honor a patient’s autonomy and to ensure informed consent is adequately obtained
- Key idea: Under HIPAA laws, you should not discuss the patient’s condition with anyone else unless you obtain explicit permission or the patient loses decision-making capacity
16) A 10-month-old boy is brought to the physician for a follow-up examination. He has had a mass on the back…
Vascular proliferation
- Infant is brought in for an enlarging red mass on the back of his neck that has visible areas of central ulceration, most concerning for a hemangioma
- Key idea: Most hemangiomas grow for ~6 months and then regress within ~5 years
- Key idea: Ulcerated hemangiomas or hemangiomas in cosmetically-sensitive areas (face) can be treated with topical beta blockers (propranolol) that both promote vasoconstriction and block growth factors
- Lymphatic hypertrophy –> Cystic hygroma (associated with Turner syndrome) –> Swelling behind neck or around face often without superficial skin changes
17) A 42-year-old man comes to the physician because of a 1-month history of generalized itching and fatigue. He has chronic…
Secondary hyperparathyroidism
- Primary hyperparathyroidism –> Parathyroid hyperplasia/carcinoma with autonomous production of PTH regardless of Ca levels leads to hypercalcemia and hypophosphatemia
- Secondary hyperparathyroidism –> Chronic hypocalcemia in setting of CKD (decreased vitamin D activation and excessive phosphate-calcium binding) –> High PTH with low calcium levels unresponsive to PTH with osteitis fibrosa cystica (bone disease with “brown tumors”)
- Tertiary hyperparathyroidism –> CKD patient with chronic secondary hyperparathyroidism who has had a chronically overstimulated parathyroid gland (due to low Ca) and ultimately develops an autonomously productive portion of the parathyroid gland leading to the same picture as primary hyperparathyroidism (high calcium)
- Causes of pruritis without rash:
- Liver disease
- Renal disease
- Thyroid disease
- Hodgkin lymphoma
- Type 2 diabetes
18) A 57-year-old man is admitted to the hospital because of a 1-month history of profuse, watery diarrhea with facial flushing…
VIPoma
- Middle-aged man presents with Watery Diarrhea and Hypokalemia with increased stool potassium levels, concerning for a possible VIPoma
- Key idea: VIPoma classically leads to WDHA syndrome, which includes Watery Diarrhea, Hypokalemia and Achlorydia
- Key idea: VIPomas can be a component of MEN 1 syndrome (pancreatic tumors, pituitary tumors and parathyroid hyperplasia/carcinoma)
- Note: Unclear why patient has a prominent metabolic alkalosis (given that patients with profuse diarrhea often have non-AG metabolic acidosis), but could potentially rationalize patient has severe hypovolemia –> Increased RAAS activity –> Increase secretion of H+ into kidney tubules in exchange for Na+ –> “Contraction alkalosis”
- Gastrinoma –> Zollinger Ellison syndrome –> Ulcers distal of duodenum, multiple ulcers in stomach/duodenum refractory to PPI/H2 blocker
- Glucagonoma –> Diabetes, DVT, Dermatitis, Depression
- Insulinoma –> Episodes of hypoglycemia with increased C-peptide levels (differentiate from exogenous insulin)
19) A hospitalized 67-year-old man has chest pain 3 days after undergoing a left colectomy for adenocarcinoma of the sigmoid…
Cardiac Output: Decreased // Pulmonary Capillary Wedge Pressure: Increased // Systemic Vascular Resistance: Increased
- Elderly man 3 days post-op from a colectomy develops symptoms concerning for inferior wall myocardial infarction (ST elevations in leads II, III and aVF) with borderline hypotension and crackles halfway up the lung bases, concerning for cardiogenic shock
- Lead elevations and type of MI:
- I, aVL: Lateral MI, lateral circumflex artery
- V1-V4: Anterior MI, left anterior descending artery
- V5-V6: Anterolateral, can be component of lateral MI or anterior MI
- II, III, aVF: Inferior MI, Right coronary artery
20) An 82-year-old woman is brought to the physician for a follow-up examination 2 months after she sustained a right hip…
Increased parathyroid hormone concentration
- Elderly woman with osteoporosis presents following a right hip fracture and is found to have a normal serum calcium concentration with decreased 25-hydroxyvitamin D, concerning for hypovitaminosis D. Given that vitamin D exerts negative feedback on PTH production, we would expect PTH levels to be high despite calcium levels
- Causes of hypovitaminosis D:
- Nutritional deficiency (elderly patient, eating disorder)
- Chronic kidney disease (decreased 1-alpha hydroxylation of vitamin D in kidneys)
- Fat malabsorption (chronic pancreatitis, celiac disease, etc.)
21) A 60-year-old woman comes to the emergency department 1 hour after the acute onset of a severe diffuse headache…
Subarachnoid hemorrhage
- Middle-aged woman presents with acute severe headache with altered mental status, nuchal rigidity and signs of bilateral UMN lesions with a CT scan showing a bleed in the basal cisterns and sulci, concerning for a nontraumatic subarachnoid hemorrhage
- Key idea: Subarachnoid hemorrhage classically presents as “worse headache in my life” and can occur due to trauma but also due to non-traumatic rupture of a berry aneurysm (often a bleed on the bottom of the brain [basal cisterns])
- Key idea: Meningismus (nuchal rigidity, etc.) can be seen in either meningitis OR subarachnoid hemorrhage (HIGH-YIELD!!!)
22) A 32-year-old man is brought to the emergency department 45 minutes after being involved in a motorcycle collision…
Hypovolemia
- Young man brought to ED after motor vehicle accident is found to have hypotension, tachycardia, and altered mental status without other localizing signs, and therefore should be assumed to be in hypovolemic shock!
- Cardiac contusion –> Would have significant bruising over the anterior chest
- Aspiration –> Aspiration pneumonitis does not commonly lead to hypovolemia, and it would take >2 days before aspiration pneumonia would develop (which could lead to sepsis –> hypotension)
- Neurogenic shock –> Loss of sympathetics –> Hypotension and bradycardia
- Spinal cord injury –> Unable to move extremities freely
23) A 27-year-old woman comes to the emergency department because of a 6-day history of right flank pain that radiates to her…
Increased absorption of oxalate
- Young woman with history of Crohn disease presents with acute right flank pain radiating to groin with CT demonstrating a kidney stone, most likely a calcium-oxalate kidney stone in the setting of terminal ileal disease
- Functions of terminal ileum: Absorption of B12 and Bile salts
- Complications of terminal ileal disease (classically Crohn’s disease):
- B12 deficiency (megaloblastic anemia with neurologic symptoms)
- Loss of bile salts:
- Fat malabsorption (deficiency of vitamins A/D/E/K, weight loss, voluminous stools)
- Fat malabsorption –> Increased fat in the intestines –> Increased binding of fat to calcium in GI tract –> Decreased binding between calcium and oxalate within GI tract –> Increased free oxalate in GI tract –> Increased oxalate reabsorption –> Increased propensity for calcium-oxalate kidney stones
24) A previously healthy 37-year-old man comes to the physician because of blurred vision for 2 weeks. His blood pressure…
Pituitary adenoma
- Key idea: Bitemporal hemianopsia seen with lesions of the optic chiasm, with the two major examples being pituitary adenomas (adult patient, most commonly prolactinomas [galactorrhea, infertility, etc.]) and craniopharyngiomas (pediatric patient, calcified mass)
- Key idea: The right visual cortex senses the LEFT VISUAL FIELD, whereas the left visual cortex senses the RIGHT VISUAL FIELD, which is the reason for the crossover at the optic chiasm
25) A previously healthy 15-year-old girl is brought to the emergency department 1 hour after the sudden onset of difficulty…
Air collection in the pleural space
- Adolescent who is tall and skinny presents with sudden onset pleuritic, sharp chest pain and is found to have asymmetric breath sounds with hyperresonance over areas of decreased breath sounds, concerning for a spontaneous pneumothorax
- Two basic types of pneumothorax:
- Spontaneous pneumothorax (Collapsed lung (chest pain, dyspnea) WITHOUT hemodynamic instability)
- Commonly seen in thin, young individuals (classically men) or secondary to rupture of a bullae in the setting of underlying pulmonary disease (COPD)
- Tx: Observation (<2 cm) versus Needle thoracostomy (>2 cm, not self-resolving)
- Tension pneumothorax (Collapsed lung WITH hemodynamic instability)
- Commonly due to penetrating trauma (motor vehicle accident) or iatrogenic (central line placement, mechanical ventilation)
- Tx: Immediate needle thoracostomy to prevent hemodynamic collapse
- Spontaneous pneumothorax (Collapsed lung (chest pain, dyspnea) WITHOUT hemodynamic instability)
- Lung exam findings:
- Hyperresonant –> Less dense than normal lung –> Air –> Pneumothorax
- Hyporesonant –> More dense than normal lung –> Water, Blood or pus –> Pulmonary edema, pleural effusion, hemothorax, pneumonia, etc.
- Pleuritic chest pain differential:
- Pericarditis
- Pleuritis
- Pulmonary embolism
- Pneumothorax
26) An 18-year-old woman is brought to the emergency department 20 minutes after she sustained severe head injuries in…
Increased intracranial pressure
- Young woman with severe traumatic head injuries presents with altered mental status with hypertension and bradycardia, most likely due to increased intracranial pressure
- Key idea: Increased intracranial pressure classically leads to Cushing’s triad of hypertension, bradycardia and respiratory depression
- ICP increase –> ICP greater than Mean arterial pressure in the brain –> Cerebral hypoperfusion –> Sympathetic stimulation with increased blood pressure –> Increased blood pressure signals baroreceptors –> Increased parasympathetic outflow to heart leads to bradycardia
- Increased ICP –> Brain stem dysfunction –> Respiratory depression
- Low blood pressure + Tachycardia –> Shock (cardiogenic, hypovolemic, obstructive, distributive)
- High blood pressure + Tachycardia –> Sympathetic overstimulation (cocaine/meth use, pheochromocytoma, delirium tremens, etc.)
- High blood pressure + Bradycardia –> Increased intracranial hypertension (trauma, brain mass, idiopathic intracranial hypertension in young overweight woman)
27) A 77-year-old woman is admitted to the hospital because of severe cramping pain in the lower abdomen. The pain has been constant…
Sigmoid volvulus
- Elderly woman with acute, constant, cramping abdominal pain is found to have severe distention of the sigmoid colon on abdominal x-ray (“coffee bean” sign), concerning for sigmoid volvulus
- Key idea: Next best step is flexible sigmoidoscopy (to detorse sigmoid volvulus) with placement of a rectal tube (to facilitate stool passage and decreased recurrence in acute setting)
- Ileus –> Often seen in a patient who is post-op and/or using opiates
- Small bowel obstruction –> Air-fluid levels in the small intestine
28) A 70-year-old man has a 2-year history of progressive dysphagia and intermittent regurgitation of…
Cricopharyngeal muscle spasm
- Elderly man with chronic progressive dysphagia and food regurgitation has a barium swallow performed that demonstrates accumulation of dye within an anterior diverticulum of the proximal esophagus, concerning for Zenker’s diverticulum
- Key idea: Uncoordinated swallowing –> Cricopharyngeal muscle spasm –> Diverticular formation of the superior esophagus (which is weakened over time)
- Absence of peristalsis –> Achalasia –> Dysphagia to solids and liquids with “bird-beak” sign on barium swallow
- Diffuse esophageal spasm –> Dysphagia + chest pain when swallowing
29) A 24-year-old man comes to the emergency department 60 minutes after the suddn onset of tearing chest pain…
Administration of labetalol
- Young man who is tall and skinny (marfanoid?) presents with sudden onset tearing chest pain radiating to the back and is found to have unequal blood pressures between his arms with a widened mediastinum on chest x-ray, concerning for aortic dissection –> Best next step is a beta blocker
- Key idea: In setting of aortic dissection, your initial goal is to maintain adequate blood pressure while decreasing further propagation of the tear, with beta blockers helping to target the second goal by decreasing cardiac contractility –> Decreased peak systolic blood pressure –> Decreased force on aortic wall
- Aortic dissection in young man –> Connective tissue disorder (Marfan’s, Ehlers-Danlos) or stimulant usage (cocaine/meth)
- Widened mediastinum –> Aortic or esophageal pathology
- Unequal blood pressure in arms –> Aortic pathology (Takayasu’s arteritis, aortic dissection, etc.) or Subclavian steal syndrome (recurrent syncope when exerting one arm)
30) A 25-year-old man comes for a routine health maintenance examination. A harsh systolic murmur is heard…
Calcification of the valve
- Key idea: Aortic stenosis typically occurs due to dystrophic valvular calcification in the setting of cumulative shearing stress, with patients with bicuspid aortic valves undergoing an accelerated version of the same pathologic process due to 2 valves performing the job of 3 –> suboptimal valve mechanics in opening/closing
31) A 2-day-old male newborn has a 6-hour history of shortness of breath and blue lips and extremities. He was born at term…
Echocardiography
- Newborn who presents on day 2 of life with central cyanosis, hypoxia refractory to supplemental oxygen, diffuse crackles in both lungs and a loud S2 with chest x-ray showing cardiomegaly and pulmonary congestion, concerning for cyanotic heart disease
- Key idea: Hypoxia refractory to supplemental oxygen indicative of a shunt because that is either intracardiac or intrapulmonary blood that perfuses but is not ventilated
- Key idea: Common for patients with cyanotic heart disease to present with hypoxia and circulatory issues within first few days of life when the PDA closes
- Causes of cyanotic heart disease –> 5 T’s
- persistent Truncus arteriosus (1 outflow tract for aorta and pulmonary arteries)
- Transposition of the great vessels (2 vessels are switched with aorta coming out of RV and pulmonary artery coming out of LV)
- Tricuspid atresia (lack of hole between the RA and RV)
- Tetralogy of Fallot (Ventricular septal deviation towards RV –> Pulmonic stenosis –> RV hypertrophy –> VSD –> Overriding aorta)
- Total anomalous pulmonary venous return (pulmonary veins drain into RA)
- Key idea: Peripheral cyanosis (fingers/toes) is normal and basically expected, but central cyanosis (trunk/face) is never normal!
- Administration of surfactant –> Neonatal respiratory distress syndrome (preterm baby with hypoxia and diffuse whiteout of both lungs)
32) A 57-year-old man comes to the physician because of a 4-week history of mild abdominal cramps, foul-smelling stools, and intermittent…
Pancrelipase
- Middle-aged man with history of distal pancreatectomy for chronic pancreatitis presents with foul-smelling stools and post-prandial diarrhea, concerning for possible fat malabsorption due to pancreatic exocrine insufficiency
- Key idea: Although stool is generally foul-smelling, on the NBME exam when the test writers are describing the stool as foul-smelling, voluminous or greasy, then consider fat malabsorption
- Causes of postprandial abdominal pain:
- Chronic pancreatitis: Epigastric, recurrent bouts of pancreatitis (alcoholic, cystic fibrosis)
- Biliary colic: RUQ pain, often overweight 40-year old woman
- Chronic mesenteric ischemia: Crampy diffuse pain, elderly patient with atherosclerotic risk factors
- Peptic ulcer disease –> Upper epigastric gnawing pain, associated with H. pylori infection and NSAIDs
33) A 62-year-old man with alcoholism comes to the emergency department because he has vomited bright red blood…
Intravenous fluid therapy and blood transfusion
- Middle aged man with alcoholism presents with recurrent hematemesis with endoscopy demonstrating a posterior duodenal ulcer and is found to be hypotensive and tachycardic with possible orthostatic hypotension –> First step is to ensure patient has ABCs (Airway, Breathing, Circulation), so in this patient with hypotension we should give isotonic fluids +/- blood products
34) A previously healthy 23-year-old man comes to the physician because of a 3-month history of fatigue. He reports…
Splenectomy
- Young man with strong family history of splenectomies for unknown reason presents with chronic fatigue presents with pale conjunctivae, splenomegaly and a blood smear showing spherocytes, concerning for hereditary spherocytosis –> Treat with splenectomy (given RBCs are being cleared by the spleen)
- Key idea: Spherocytes seen in hereditary spherocytosis (patient of Northern European ancestry, family history of anemia/splenectomy, negative Coombs test) and autoimmune hemolytic anemia (positive Coombs test, patients with CLL, SLE, mycoplasma infection)
- Key idea: Classic lab test associated with hereditary spherocytosis is increased mean corpuscular hemoglobin concentration (MCHC)
35) A 37-year-old man comes to the physician because of bilateral breast enlargement for 6 months. He takes no medications…
Leydig cell tumor
- Young man presents with a small nodule on the left testicle and bilateral tender gynecomastia with a normal beta-hCG concentration, concerning for a hormone-producing testicular tumor such as a Leydig cell tumor
- Key idea: Although leydig cell tumors classically lead to hyperandrogenism in men and women, they can also produce estrogen
- Key idea: In women with signs of hyperestrogenism (post-menopausal bleeding, breast enlargement/tenderness, etc.) and an adnexal mass, consider granulosa cell tumor
36) A 52-year-old man is brought to the emergency department by his wife because he has been excessively sleepy…
Paracentesis
- Middle-aged man with signs consistent with cirrhosis (jaundice, muscle wasting, spider angiomata, ascites, increased INR) presents with acute confusion, fever and abdominal tenderness, concerning for possible spontaneous bacterial peritonitis (SBP) [infection of ascitic fluid]
- Key idea: Anytime a patient with cirrhosis presents with altered mental status, diffuse abdominal tenderness or temperature > 100.4 F, your index of suspicion for SBP should be VERY HIGH and the next best step is paracentesis
- Key idea: PMNs > 250/mm^3 in the ascitic fluid is diagnostic for SBP
- In setting of SBP, third generation cephalosporin (ceftriaxone) is best treatment and a fluoroquinolone (ciprofloxacin) is often used for prophylaxis moving forward
37) A 62-year-old woman comes to the physician because of ulcers on her right ankle for 6 months. There is no history…
Venous insufficiency
- Middle-aged woman with history of diabetes and chronic bilateral ankle swelling who presents with bilateral lower leg hyperpigmentation with ulceration of the medial aspect of the ankle, concerning for a venous stasis ulcer
- Key idea: Chronic venous stasis can lead to changes to the overlying skin (e.g., venous stasis dermatitis, retention hyperkeratosis) and classically leads to ulcers on the medial shin
- 3 major ulcer types:
- Venous stasis ulcer: Medial shin, chronic bilateral leg swelling
- Arterial ulcer: Distal toes or lateral ankle, often patient with atherosclerotic risk factors and other signs of arterial insufficiency (claudication, shiny skin on legs without hair, etc.)
- Diabetic ulcer: Pressure points (classically on the sole of the foot near the big toe), patient with longstanding poorly controlled diabetes
- Thromboangiitis obliterans –> Ulceration of the fingers toes among male smokers, medium-vessel vasculitis
38) A 57-year-old woman has had pain of the left groin and distal anterior thigh with weight bearing for 3 months. She has difficulty…
Osteoarthritis of the hip
- Middle-aged woman presenting with left groin and thigh pain that is worse with exertion, concerning for hip osteoarthritis
- Key idea: Hip pathologies (osteoarthritis, avascular necrosis, etc.) classically lead to pain located in the groin
- Key idea: Treatments include weight loss, physical therapy, NSAIDs, intraarticular steroid injections, and hip replacement surgery
39) During transfusion of a second unit of crossmatched packed red blood cells, a 62-year-old man has the sudden onset…
Nonhemolytic transfusion reaction
- Middle-aged man who is receiving packed RBCs and develops acute fever, chills, dyspnea and fever with a negative Coombs test and no urinary changes, most concerning for nonhemolytic transfusion reaction –> Best treatment is an antipyretic such as acetaminophen
- Acute hemolytic transfusion reaction –> Fever, hypotension, flank pain, dark urine (hemoglobinuria)
- Anaphylactic transfusion reaction –> Urticaria, GI symptoms, bronchoconstriction, hypotension
- Transfusion-related acute lung injury –> Dyspnea with diffuse bilateral infiltrates on CXR but no heart abnormalities (S3, JVD, etc.)
40) A 40-year-old woman comes to the physician for a follow-up examination. She recently tested positive for the…
Bilateral mastectomy and oophorectomy
- BRCA mutation –> Breast cancer and ovarian cancer –> Remove organs prophylactically to decrease cancer risk
- Lynch syndrome –> Colorectal, endometrial, ovarian and skin cancer
- Retinoblastoma mutation –> Retinoblastoma and osteosarcoma
41) A 32-year-old woman comes to the emergency department 24 hours after the onset of severe abdominal cramps and…
Colonoscopy
- Young woman with chronic abdominal cramps, diarrhea and 15 lbs of weight loss presents with acute, severe abdominal pain and is found to be underweight with RLQ tenderness, leukocytosis and a CT scan showing terminal ileal thickening, concerning for Crohn disease –> Best next diagnostic step in setting of chronic abdominal pain in a young patient concerning for IBD would be colonoscopy
- Key idea: Crohn’s disease classically affects the terminal ileum and spares the rectum, while Ulcerative colitis always affects the rectum and spares the terminal ileum
42) A previously healthy 47-year-old woman comes to the physician because of a 3-month history of mild hearing loss…
Acoustic neuroma
- Middle-aged woman presents with chronic progressive sensorineural hearing loss (CN8), tinnitus, decreased sense of taste (CN7) and ataxia (CN8), concerning for a possible acoustic neuroma (schwannoma)
- Key idea: Acoustic neuromas most commonly develop at the pontomedullary junction and therefore commonly impinge upon multiple cranial nerves that project from that area, including CN5 (decreased facial sensation), CN7 (facial weakness), and CN8 (hearing loss, vertigo)
- Meniere disease –> Intermittent episodes of peripheral vertigo lasting minutes-hours associated with hearing loss and tinnitus
- Otosclerosis –> Conductive hearing loss
- Pituitary adenoma –> Bitemporal hemianopsia with endocrine abnormalities
43) A 72-year-old man comes to the physician because of a 4-month history of right-sided upper abdominal pain…
Endoscopic retrograde cholangiopancreatography
- Elderly man with alcoholism presents with chronic history of weight loss (20 lbs) and RUQ pain and is found to have cholestatic liver injury (increased alkaline phosphatase and direct bilirubin) with abdominal ultrasound showing dilated intrahepatic ducts and a small gallbladder, concerning for possible malignant obstruction of the bile duct (pancreatic cancer or cholangiocarcinoma) –> Best next step would be ERCP
- Key idea: Indications for ERCP include acute cholangitis (RUQ pain + jaundice + fever), pancreatic mass/malignancy (adenocarcinoma, pseudocyst, etc.) and possible cholangiocarcinoma (NOT GALLSTONE PANCREATITIS UNLESS YOU’RE WORRIED ABOUT CONCOMITTANT CHOLANGITIS!!!)
- Key idea: Most common cause of cholestatic liver injury is gallstone-related disease, but in this patient who has no gallstones visualized in the gallbladder we would have to consider alternative diagnoses, with the significant weight loss increasing concern for malignancy
- Key idea: Pancreatic cancer classically seen in smoker who presents with epigastric/back pain and new-onset diabetes, so most likely cholangiocarcinoma in this case
- LFT abnormalities can generally be broken down into:
- Hepatocellular (ALT/AST increase >>> Alk phos and bilirubin increase)
- Toxins (acetaminophen, alcohol, etc.)
- Ischemia (shock liver in setting of sepsis/hypovolemia)
- Viruses (hepatitis A-E, CMV, VZV, etc.)
- Other (autoimmune hepatitis, Wilson disease, etc.)
- Cholestatic (Alk phos and direct bilirubin increase >> ALT/AST increase)
- Choledocholithiasis +/- acute cholangitis
- Pancreatic cancer (head) or cholangiocarcinoma
- Primary sclerosing cholangitis
- Primary biliary cirrhosis
- Hepatocellular (ALT/AST increase >>> Alk phos and bilirubin increase)
44) An 82-year-old woman is admitted to the hospital because she has refused to eat because of a 2-day history of severe abdominal…
Mesenteric angiography
- Elderly woman presents with acute severe abdominal pain with a fairly benign physical exam (“pain out of proportion to exam’) with labs consistent with an anion-gap metabolic acidosis and CT demonstrating thickening of the small bowel wall, concerning for possible acute mesenteric ischemia –> Next best step is mesenteric angiography
- Key idea: Colonoscopy would demonstrate edematous and friable mucosa
- Key idea: Anion-gap metabolic acidosis likely due to lactic acidosis due to ischemia
- Key idea: “Pain out of proportion to exam” is classically associated with acute mesenteric ischemia and necrotizing fasciitis
45) A previously healthy 32-year-old woman is brought to the emergency department 30 minutes after a motor vehicle…
Anteriography
- Young man brought to the ED after a motor vehicle collision is found to have pain, tingling, paralysis and pallor of his right leg with absent pulses and posterior dislocation of the right knee. Reduction of the posterior knee dislocation leads to regained motor function, but patient should undergo CT angiography given risk of popliteal artery injury
- Approach to posterior knee dislocation:
- 1st step: Reduce joint dislocation
- 2nd step: Perform vascular examination (checking popliteal/distal pulses, duplex ultrasonography and ankle-brachial index)
- If limb ischemic –> Surgical intervention
- If limb perfused with normal vascular exam –> Serial vascular examinations
- If limb perfused with abnormal vascular exam –> CT angiography +/- vascular surgery consultation
46) A 67-year-old woman is brought to the emergency department because of a 2-day history of increasingly severe abdominal cramps…
Ovarian cancer
- Elderly woman with chronic bloating presents with acute severe abdominal cramping with abdominal x-ray demonstrating air-fluid levels concerning for small bowel obstruction. Laparotomy is performed with omental caking observed with markedly enlarged, nodular ovaries with pathology demonstrating psammoma bodies, concerning for ovarian cancer
- Key idea: Psammoma bodies associated with papillary thyroid cancer, meningiomas and papillary serous cystadenocarcinoma of the ovary
- Common causes of small bowel obstruction:
- Adhesions (prior open abdominal surgery)
- Malignancy (chronic weight loss, cancer risk factors)
- Hernia (inguinal/umbilical bulge)
47) A 42-year-old woman comes to the physician because of a 3-month history of episodes of headache, sweating…
Phenoxybenzamine
- Young woman with a history of refractory severe hypertension presents with episodic headache, sweating and tachycardia and is found to have severe hypertension with elevated urine metanephrines and a right adrenal gland mass on imaging, concerning for a pheochromocytoma –> Next best step is start phenoxybenzamine (alpha blocker), then a beta blocker, and then take patient for surgery
- Key idea: Concern is that manipulation of pheochromocytoma during surgery can lead to release of epinephrine/norepinephrine that will trigger significant sympathetic hyperstimulation, so optimal approach is to alpha block and beta block patient prior to surgery
- Key idea: Given theoretical risk of significant hypertension due to “unopposed alpha agonism” if patients with sympathetic overstimulation are started on a beta-blocker, it is recommended that an alpha antagonist is started before a beta blocker (same reason beta blockers aren’t routinely given to patients with cocaine intoxication)
- Key idea: Phenoxybenzamine is an irreversible alpha antagonist used for pheochromocytoma, whereas phentolamine is a reversible alpha antagonist used for MAO-induced hypertensive crisis (patient on MAO inhibitor who eats wine/cheese/meat and then presents with severe hypertension)
48) A previously healthy 42-year-old woman, gravida 2, para 2, comes to the physician because of a 1-month history…
Intraductal papilloma
- Young woman presents with unilateral serosanguineous discharge with normal mammography, concerning for intraductal papilloma (#1 cause of unilateral bloody nipple discharge!)
- Fibroadenoma –> Soft, mobile mass in upper outer quadrant of mass in young woman that changes in size with menstrual cycles
- Fibrocystic changes of the breast –> Bilateral “lumpy-bumpy” breasts
49) A previously healthy 20-year-old man is brought to the emergency department by his friend 1 hour after being thrown…
Tracheal intubation and ventilation
- Young man is brought to the ED after a traumatic head injury in which he had loss of consciousness –> brief lucid interval –> progressively altered mental status and is found to have hypertension + bradycardia (concerning for intracranial hypertension) with asymmetric pupils (concerning for uncal herniation) and decorticate posturing found to have convex hyperintensity not crossing suture lines, concerning for epidural hematoma
- Key idea: First step in managing all patients (especially trauma/emergency patients) is maintaining ABC –> Airway, Breathing and Circulation, so in this patient with altered mental status we would want to secure his airway with intubation and then begin treatments to manage epidural bleed (mannitol to decrease intracranial pressure, emergency neurosurgical decompression, etc.)
- Common indications for intubation:
- Expanding hematoma, emphysema or swelling in neck/airway
- Glasgow-Coma score of 8 or less (Eight –> Intub-Eight)
- Severe inhalation injury (caught in house fire and has ash/soot on face/airway)
- Breathing is noisy (stridor, gurgles)
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