Free USMLE Step 2 CK Exam Flashcards

Decision-making capacity, not a court finding of competence. Capacity is a clinical, decision-specific judgment that the patient can understand the facts, appreciate how they apply to their own situation, reason through the options, and state a consistent choice. A patient with capacity may refuse treatment even when refusal causes death.

Substituted judgment: decide what this patient would have chosen, using prior statements, values, and known preferences. Only when those are genuinely unknown does the surrogate fall back on the best-interest standard, which weighs benefits and burdens as a reasonable person would.

Yes. Every state lets minors consent on their own to testing and treatment of sexually transmitted infections, and most states also allow independent consent for contraception, prenatal care, and substance use treatment. Emancipated minors, meaning those who are married, in the military, or court-declared, consent to all of their care. Breaking confidentiality here drives adolescents away from treatment.

Disclose the error to the patient and file an institutional event report. Disclosure is owed even when harm is transient or absent, and blame-free reporting is what lets the system find and fix the underlying failure. Concealment is a professionalism violation, not a kindness.

Root cause analysis is retrospective: it dissects an event that already happened to expose system-level causes instead of assigning individual blame. Failure mode and effects analysis is prospective: it maps a process before harm occurs and ranks each potential failure by severity, frequency, and how easily it would be detected.

The connector is strongest because it is a forcing function that makes the error impossible. Checklists and standardized protocols sit in the middle. Education and reminders are weakest, because they depend on human memory and vigilance under fatigue and workload.

Prerenal: fractional excretion of sodium under 1 percent, urine sodium under 20 mEq/L, and bland sediment, because intact tubules avidly reabsorb sodium. Acute tubular necrosis: fractional excretion above 2 percent, urine sodium above 40 mEq/L, and muddy brown granular casts. Diuretics invalidate the sodium index, so use fractional excretion of urea instead.

Aim for a rise of 4 to 6 mEq/L in 24 hours and never exceed about 8 mEq/L in any 24-hour period. Faster correction risks osmotic demyelination syndrome, which surfaces days later with dysarthria, dysphagia, and quadriparesis. If you overshoot, relower the sodium with free water and desmopressin.

Torsion: abrupt severe pain, a high-riding transverse testis, an absent cremasteric reflex, and no relief with elevation. Epididymitis: gradual onset, preserved cremasteric reflex, and pain eased by elevation. Torsion is a surgical emergency with a salvage window of about 6 hours, so explore rather than wait on imaging.

Nephritic: hematuria with dysmorphic red cells and red cell casts, hypertension, oliguria, and sub-nephrotic proteinuria. Nephrotic: proteinuria above 3.5 g per day, hypoalbuminemia, heavy edema, and hyperlipidemia, plus a thrombotic risk driven by urinary loss of antithrombin.

Keep dietary calcium normal. Restricting it frees intestinal oxalate for absorption and raises stone risk. The changes that work are fluid intake sufficient for at least 2.5 liters of urine daily, less sodium, moderated animal protein, and limits on high-oxalate foods. Calcium taken as a supplement away from meals is the exception to avoid.

Transfer if primary PCI can be delivered within 120 minutes of first medical contact. If it cannot, give fibrinolysis within 30 minutes of arrival and then transfer for angiography. At a PCI-capable center the target is device time within 90 minutes of first medical contact.

Survival benefit: an ARNI or an ACE inhibitor or ARB, an evidence-based beta blocker such as carvedilol, metoprolol succinate, or bisoprolol, a mineralocorticoid receptor antagonist, and an SGLT2 inhibitor. Loop diuretics and digoxin ease congestion and cut admissions but do not extend life.

The onset of symptoms: exertional angina, syncope, or heart failure. Survival falls steeply once symptoms appear, so symptom onset by itself is the trigger for surgical or transcatheter replacement. Asymptomatic severe stenosis is also treated when the ejection fraction drops below 50 percent.

Either 3 weeks of therapeutic anticoagulation beforehand, or a transesophageal echocardiogram showing no left atrial thrombus. Anticoagulate at least 4 weeks afterward either way, because the stunned atrium keeps forming clot even after sinus rhythm returns.

Pain far out of proportion to the skin findings, progression measured in hours, systemic toxicity, crepitus, hemorrhagic bullae, and anesthesia of the involved skin. Imaging must not delay care: the diagnosis is confirmed and treated in the operating room with debridement plus broad-spectrum antibiotics.

No. Crystal disease and infection coexist. Send Gram stain, culture, and a cell count on every joint aspirate. A synovial white cell count above roughly 50,000 per microliter with neutrophil predominance points to infection, and empiric antibiotics plus drainage start before cultures return.

SJS and toxic epidermal necrolysis involve mucous membranes, split at the dermal-epidermal junction, and are usually drug-triggered in adults. Staphylococcal scalded skin spares mucosa, splits within the superficial granular layer, and mostly affects young children. Stopping the culprit drug at once is the single highest-impact step in SJS and TEN.

Saddle anesthesia, new urinary retention with overflow incontinence, fecal incontinence, and bilateral leg weakness signal cauda equina syndrome. Emergent MRI and surgical decompression preserve function. Once the bladder is denervated, recovery of continence and sexual function is often incomplete.

Serotonin syndrome builds within hours and produces hyperreflexia, clonus that is worse in the legs, diarrhea, and dilated pupils. Neuroleptic malignant syndrome builds over days with lead-pipe rigidity, hyporeflexia, and a markedly elevated creatine kinase. Treatment diverges: cyproheptadine versus dantrolene with bromocriptine.

It reveals bipolar disorder. An antidepressant given alone can precipitate mania or accelerate cycling. Treat bipolar depression first with a mood stabilizer such as lithium or lamotrigine, or an atypical antipsychotic such as quetiapine or lurasidone.

Anorexia is defined by significantly low body weight from restriction, and brings bradycardia, hypotension, hypothermia, amenorrhea, and low bone density. Bulimia occurs at normal or higher weight with binge and purge cycles, and shows parotid swelling, dental erosion, knuckle calluses, and hypokalemic metabolic alkalosis.

Tremor, anxiety, and autonomic arousal at 6 to 24 hours. Withdrawal seizures at 12 to 48 hours. Alcoholic hallucinosis at 12 to 24 hours in a patient who remains oriented. Delirium tremens at 48 to 96 hours with disorientation and autonomic instability. Only delirium tremens carries substantial mortality.

Iron deficiency: low ferritin, high total iron-binding capacity, low transferrin saturation, and a widening red cell distribution width. Anemia of chronic disease: low or normal iron-binding capacity with normal or high ferritin, because ferritin is an acute-phase reactant that rises with inflammation and can mask a true deficiency.

The anemia improves while the neurologic injury advances. B12 deficiency causes subacute combined degeneration with loss of vibration sense and proprioception, and that damage can become permanent. Methylmalonic acid settles it: elevated in B12 deficiency, normal in isolated folate deficiency.

Stop every heparin exposure, including catheter flushes and coated lines, and start a non-heparin anticoagulant such as argatroban or fondaparinux. Do not transfuse platelets and do not start warfarin alone: heparin-induced thrombocytopenia causes thrombosis, and early warfarin can trigger venous limb gangrene.

TTP leaves prothrombin time, partial thromboplastin time, and fibrinogen normal, with severe ADAMTS13 deficiency driving platelet consumption. DIC prolongs both clotting times, consumes fibrinogen, and raises D-dimer. TTP needs urgent plasma exchange, and platelet transfusion can worsen its thrombosis.

Octreotide to lower portal pressure, prophylactic ceftriaxone, and urgent endoscopy with band ligation. Antibiotics independently lower mortality in cirrhotic gastrointestinal bleeding by preventing spontaneous bacterial peritonitis and early rebleeding.

An ascitic absolute neutrophil count of at least 250 cells per microliter, whether or not the culture grows. Start cefotaxime immediately and give albumin on day 1 and day 3 to lower the risk of hepatorenal syndrome. Waiting for the culture delays treatment that changes survival.

Goal-directed isotonic crystalloid, analgesia, and early enteral feeding as soon as it is tolerated. Prophylactic antibiotics are not indicated for sterile necrosis. Prolonged bowel rest with parenteral nutrition raises infectious complications compared with feeding the gut.

Average risk starts at age 45. With a first-degree relative diagnosed before age 60, or two first-degree relatives at any age, begin colonoscopy at age 40 or 10 years before the youngest relative's diagnosis, whichever comes first, and repeat every 5 years.

The patient is within 4.5 hours of the last known well time, a non-contrast head CT shows no hemorrhage, and blood pressure is below 185/110, lowered first if it is higher. Recent intracranial surgery, active internal bleeding, and known coagulopathy exclude treatment. Time from onset drives every decision.

Lumbar puncture looking for xanthochromia and a red cell count that does not clear from the first tube to the last. CT sensitivity for subarachnoid hemorrhage falls off after roughly 6 hours from onset, so a normal scan late in the course does not rule it out.

Thiamine before or together with the glucose. A glucose load consumes the last of the thiamine reserve and can precipitate Wernicke encephalopathy, whose triad is confusion, ophthalmoplegia, and ataxia. Untreated Wernicke can progress to irreversible Korsakoff amnesia with confabulation.

This is acute angle-closure glaucoma. Avoid mydriatics and anticholinergics, including many antihistamines and antiemetics, because pupillary dilation worsens the block. Lower the intraocular pressure medically, then arrange definitive laser peripheral iridotomy.

Only at low or intermediate pretest probability, where a negative high-sensitivity D-dimer safely excludes the diagnosis. At high pretest probability a negative result cannot rule it out, so go straight to CT pulmonary angiography, or a ventilation-perfusion scan when contrast or kidney function is a barrier.

Short-acting bronchodilators, a systemic corticosteroid course of about 5 days, antibiotics when sputum purulence increases or ventilatory support is needed, and controlled oxygen targeting roughly 88 to 92 percent saturation. Add non-invasive positive pressure ventilation for hypercapnic acidosis, which lowers both intubation rates and mortality.

Control is inadequate once rescue use passes twice a week, so step up controller therapy with an inhaled corticosteroid, commonly paired with formoterol. Relying on a short-acting beta agonist alone leaves the airway inflammation untreated and raises the risk of severe exacerbation and death.

Adults aged 50 to 80 with at least a 20 pack-year history who currently smoke or who quit within the past 15 years. Screening stops once a person has gone 15 years without smoking, or develops a condition that would rule out curative treatment.

Measure lactate, draw blood cultures before antibiotics, give broad-spectrum antibiotics, and start 30 mL/kg of crystalloid for hypotension or a lactate of at least 4 mmol/L. Add norepinephrine as the first vasopressor if the mean arterial pressure stays under 65 mmHg after fluids. Each hour of antibiotic delay raises mortality.

Intramuscular epinephrine into the anterolateral thigh, repeated every 5 to 15 minutes as needed. Antihistamines and corticosteroids are adjuncts that treat neither airway edema nor shock, and substituting them for epinephrine is the most common fatal error.

Refeeding syndrome. The insulin surge drives phosphate, potassium, and magnesium into cells, risking arrhythmia, heart failure, and respiratory muscle weakness. Start at a low calorie target, give thiamine before carbohydrate, replace electrolytes aggressively, and check them daily as calories advance.

Ketoacidosis shows an anion gap metabolic acidosis with ketonemia and arterial pH below 7.3, developing over hours. Hyperosmolar hyperglycemic state shows profound hyperglycemia with serum osmolality above 320 mOsm/kg, little or no ketosis, and no significant acidosis, developing over days with a larger fluid deficit and higher mortality.

Serum TSH. If TSH is suppressed, order a radionuclide scan: a hyperfunctioning nodule is almost never malignant and is treated rather than biopsied. If TSH is normal or elevated, get an ultrasound and decide on fine-needle aspiration from nodule size and sonographic features.

It prevents eclamptic seizures. It is not an antihypertensive: severe-range blood pressure needs labetalol, hydralazine, or immediate-release nifedipine. Delivery remains the only cure. Loss of deep tendon reflexes is the earliest sign of magnesium toxicity, reversed with calcium gluconate.

Uterine atony. Start bimanual uterine massage with uterotonics: oxytocin first, then methylergonovine, avoided in hypertension, or carboprost, avoided in asthma. If bleeding persists, inspect for retained placenta, genital tract lacerations, and uterine inversion.

Sensitivity and specificity belong to the test, but predictive values depend on how common the disease is. In a low-prevalence screening population the false positives outnumber the true positives, so positive predictive value falls while negative predictive value rises.

Lead-time bias: diagnosis moves earlier without postponing death, which stretches the measured survival interval. Length-time bias compounds it by preferentially catching slow-growing disease. Judge a screening test by disease-specific mortality in a randomized trial, not by survival time.

Loss of a skill the child had already acquired. Regression points to a neurodegenerative, metabolic, or seizure disorder and is never normal variation, unlike an isolated late first step or late first word in a child who is otherwise developing normally.

Vitamin D 400 IU daily starting in the first days of life, because breast milk is a poor source, and iron beginning around 4 months until iron-rich complementary foods are established. Every newborn also receives intramuscular vitamin K at birth to prevent hemorrhagic disease of the newborn.