Cardio
A 68-year-old with an anterior STEMI suddenly becomes hypotensive. He is cool and diaphoretic. BP is 78/46, HR 118. JVD is present. Lung sounds are clear. Bedside ultrasound shows a hyperdynamic LV with a small LV cavity.
Which intervention is most appropriate initially?
A. IV furosemide
B. IV nitroglycerin
C. Cautious IV fluid administration
D. Immediate beta-blocker administration
Answer: C. Cautious IV fluid administration
Why: Inferior MI can involve the right ventricle. RV infarction causes decreased LV preload. JVD + hypotension + clear lungs = think RV infarction. These patients are often preload-dependent.
A patient with severe asthma initially has a PaCO₂ of 27 mmHg. Several hours later, the PaCO₂ is 42 mmHg, while respiratory distress continues.
Which interpretation is most concerning?
A. Improved alveolar ventilation
B. Resolution of bronchospasm
C. Development of respiratory muscle fatigue
D. Metabolic compensation
E. Excessive renal bicarbonate retention
F. Resolution of hypoxemia
Answer: C. Development of respiratory muscle fatigue
Why: Severe asthma normally produces low CO₂ from hyperventilation. A rising CO₂ can indicate the patient is becoming exhausted and failing to ventilate.
A patient develops sudden aphasia and right-sided weakness. CT shows no hemorrhage. The last-known-well time is within the treatment window. What is the most important next consideration?
A. Give aspirin immediately regardless of other factors
B. Determine eligibility for reperfusion therapy
C. Lower the BP to normal immediately
D. Administer heparin immediately
Answer: B. Determine eligibility for reperfusion therapy
Why: Acute ischemic stroke → first determine whether the patient qualifies for reperfusion treatment. Don't automatically give aspirin or anticoagulation.
A patient has K⁺ = 7.2 mEq/L and ECG shows peaked T waves and QRS widening. IV calcium gluconate is administered. What is the primary purpose of the calcium?
A. Remove potassium from the body
B. Shift potassium intracellularly
C. Stabilize the cardiac membrane
D. Increase renal potassium excretion
E. Increase insulin secretion permanently
F. Bind potassium in the intestine
Answer: C. Stabilize the cardiac membrane
A 58-year-old man presents with a pigmented lesion on his upper back. It has been slowly enlarging over 18 months. Examination shows an asymmetric 1.4-cm lesion with irregular borders and multiple shades of brown, black, and blue. Dermoscopy demonstrates an atypical pigment network with blue-white structures. Which feature is most concerning for melanoma?
A. Diameter greater than 6 mm
B. Presence of brown pigmentation
C. Lesion occurring on the back
D. Blue-white structures and an atypical pigment network
E. Slow growth over 18 months
F. Age greater than 50 years
Answer: D. Blue-white structures and an atypical pigment network
Why:Although ABCDE features are useful, dermoscopic structures can provide stronger evidence of malignancy. Atypical pigment network and blue-white structures are highly suspicious for melanoma.
A patient with atrial fibrillation has been taking warfarin. His INR is 2.4. He suddenly develops severe abdominal pain and hypotension. CT reveals a retroperitoneal hematoma.
What is the most appropriate immediate management?
A. Continue warfarin and administer vitamin K tomorrow
B. Hold warfarin and administer reversal therapy
C. Administer aspirin
D. Increase the warfarin dose because the INR is therapeutic
Answer: B. Hold warfarin and administer reversal therapy
Why: The patient has life-threatening bleeding. A "therapeutic" INR doesn't mean you continue anticoagulation during major hemorrhage.
A patient with severe asthma initially has:
PaCO₂ = 28 mmHg
Two hours later:
PaCO₂ = 40 mmHg
The patient's respiratory distress appears unchanged.Why is the second ABG concerning?
A. The patient is developing metabolic alkalosis
B. The PaCO₂ indicates improving ventilation
C. Respiratory muscle fatigue may be developing
D. The patient has developed respiratory alkalosis
Answer: C. Respiratory muscle fatigue may be developing
Why: Severe asthma → initially hyperventilating → CO₂ falls.
If the patient becomes exhausted, ventilation starts failing → CO₂ rises toward normal and then above normal.
A "normal" CO₂ in a severely struggling asthmatic can actually be bad news.
A patient with traumatic brain injury develops worsening headache, vomiting, hypertension, bradycardia, and irregular respirations. Which intervention is most appropriate?
A. Place the patient flat
B. Maintain head elevation and avoid factors that increase ICP
C. Encourage vigorous coughing
D. Administer hypotonic fluids
Answer: B. Maintain head elevation and avoid factors that increase ICP
Why: This is Cushing triad, suggesting dangerously increased intracranial pressure.
A patient taking digoxin has:
- K⁺ = 2.3
- Mg²⁺ = 1.0
- Creatinine = 2.4
He develops ventricular ectopy and nausea. Which intervention is particularly important?
A. Increase digoxin dose
B. Correct potassium and magnesium abnormalities
C. Administer calcium immediately without checking anything else
D. Give spironolactone
E. Restrict potassium
F. Give another loop diuretic
Answer: B. Correct potassium and magnesium abnormalities
A 63-year-old woman presents with a 9-mm dark lesion on the plantar surface of her foot. She has Fitzpatrick skin type VI. The lesion has irregular pigmentation and an asymmetrical shape. Which diagnosis is most likely?
A. Seborrheic keratosis
B. Acral lentiginous melanoma
C. Dermatofibroma
D. Nodular basal cell carcinoma
E. Squamous cell carcinoma in situ
F. Blue nevus
Answer: B. Acral lentiginous melanoma
Why: Melanoma on the palms, soles, and nail apparatus is classically associated with the acral lentiginous subtype. It is also important because it can occur in people with darker skin.
A patient with hypertrophic obstructive cardiomyopathy becomes hypotensive after several days of vomiting.
Which physiologic change is most likely responsible for worsening his condition?
A. Increased preload
B. Increased afterload
C. Decreased preload
D. Decreased sympathetic activity
E. Increased ventricular filling
F. Increased systemic vascular resistance
Answer: C. Decreased preload
Why: Vomiting → volume depletion → ↓ preload → smaller LV cavity → more LV outflow obstruction.
A patient with ARDS is mechanically ventilated with high PEEP. Oxygenation improves, but the patient becomes hypotensive.What is the most likely mechanism?
A. Increased pulmonary blood flow
B. Decreased intrathoracic pressure
C. Reduced venous return to the heart
D. Increased left ventricular preload
Answer: C. Reduced venous return to the heart
Why: High PEEP increases intrathoracic pressure → decreases venous return → decreases preload → hypotension.
A patient develops a sudden “worst headache of my life.” CT confirms subarachnoid hemorrhage. Five days later, she develops new unilateral weakness. Which complication is most likely?
A. Central diabetes insipidus
B. Cerebral vasospasm causing delayed cerebral ischemia
C. Acute bacterial meningitis
D. Epidural hematoma
E. Myasthenic crisis
F. Guillain-Barré syndrome
Answer: B. Cerebral vasospasm causing delayed cerebral ischemia
A patient presents 10 hours after intentionally ingesting a large amount of acetaminophen. AST and ALT are beginning to rise. Which therapy directly replenishes hepatic glutathione and reduces toxic metabolite injury?
A. Naloxone
B. Fomepizole
C. N-acetylcysteine
D. Atropine
E. Flumazenil
F. Protamine
Answer: C. N-acetylcysteine
A melanoma is excised. Pathology reports:
- Breslow thickness: 2.4 mm
- Ulceration: present
- Sentinel lymph node: negative
- No distant metastases
Which pathologic feature has the greatest direct importance in determining the primary tumor's T category?
A. Patient's age
B. Clark level alone
C. Breslow thickness and ulceration
D. Tumor color
E. Anatomic location alone
F. Presence of regional lymphadenopathy
Answer: C. Breslow thickness and ulceration
Why: Modern melanoma T staging relies heavily on Breslow thickness, with ulceration modifying the T category.
A patient with severe aortic stenosis develops exertional syncope.
Which mechanism best explains the syncope?
A. Excessive coronary perfusion
B. Inability to adequately increase cardiac output during exertion
C. Excessive LV filling
D. Acute reduction in systemic vascular resistance caused by bradycardia
E. Increased pulmonary venous return
F. Increased right ventricular contractility
Answer: B. Inability to adequately increase cardiac output during exertion
Why: The stenotic valve limits forward blood flow. During exercise, the body needs a large increase in cardiac output—but the fixed obstruction prevents it.
A patient develops sudden dyspnea three days after hip replacement. HR 132, BP 86/52, RR 34. He is anxious and hypoxemic. Lung examination is relatively clear. Which finding would most strongly support a massive pulmonary embolism?
A. Diffuse bilateral crackles
B. Elevated JVP with acute right ventricular strain
C. Bradycardia
D. Hyperresonance over both lungs
Answer: B. Elevated JVP with acute right ventricular strain
Why: A massive PE suddenly increases pulmonary vascular resistance → the right ventricle struggles → RV dilation/strain → JVD and hypotension.
A patient develops severe symptomatic hyponatremia with seizures. Serum sodium is 112 mEq/L.Which treatment is most appropriate for immediate management of severe neurologic symptoms?
A. Oral free water
B. D5W infusion
C. Hypertonic saline
D. Loop diuretic alone
E. Desmopressin alone
F. Normal saline only regardless of etiology
Answer: C. Hypertonic saline
Why: Severe symptomatic hyponatremia requires carefully controlled correction with hypertonic saline. The goal is to raise sodium enough to treat cerebral edema/symptoms while avoiding overly rapid correction.
A patient taking an SSRI is started on linezolid. Within hours he develops:
- Agitation
- Diaphoresis
- Fever
- Tremor
- Hyperreflexia
- Inducible clonus
Which diagnosis is most likely?
A. Neuroleptic malignant syndrome
B. Malignant hyperthermia
C. Serotonin syndrome
D. Anticholinergic toxicity
E. Cholinergic crisis
F. Opioid withdrawal
Answer: C. Serotonin syndrome
Why: The combination of serotonergic drugs plus clonus/hyperreflexia is the major clue.
A laboring patient develops sudden severe fetal bradycardia immediately after artificial rupture of membranes. Vaginal examination reveals a pulsating structure in front of the fetal presenting part.What is the immediate priority?
A. Oxytocin infusion
B. Encourage pushing
C. Place the patient supine
D. Elevate the presenting part and prepare for emergency cesarean delivery
E. Administer methylergonovine
F. Wait for spontaneous resolution
Answer: D. Elevate the presenting part and prepare for emergency cesarean delivery
Why: This is umbilical cord prolapse. Compression of the cord can cause acute fetal hypoxia. The presenting part should be manually elevated while preparing for emergent delivery.
A patient with acute severe mitral regurgitation suddenly develops pulmonary edema and hypotension. Echocardiography shows a normal-sized left atrium.
Why is pulmonary edema particularly severe?
A. The left atrium has become extremely compliant
B. The left ventricle cannot eject blood
C. The noncompliant left atrium experiences a rapid pressure increase
D. Pulmonary vascular resistance immediately falls
E. Right ventricular preload decreases
F. Systemic vascular resistance becomes zero
Answer: C. The noncompliant left atrium experiences a rapid pressure increase
Why: In acute MR, the LA hasn't had time to enlarge/remodel. Regurgitant blood suddenly enters the LA → pressure skyrockets → pulmonary edema.
A ventilated patient suddenly develops:
The ventilator alarm indicates high airway pressure. Which diagnosis should be suspected first?
A. Pulmonary embolism
B. Tension pneumothorax
C. Acute pulmonary edema
D. Mucus plugging of the contralateral lung
Answer: B. Tension pneumothorax
Why: Sudden deterioration + unilateral absent breath sounds + hypotension + high airway pressure is a classic tension pneumothorax picture.This is an emergency.
A patient with a spinal cord injury at T4 suddenly develops:
- Severe headache
- BP 210/110
- HR 48
- Flushing above the lesion
- Diaphoresis
- Goosebumps below the lesion
What is the first action?
A. Place the patient supine
B. Give a large IV fluid bolus
C. Sit the patient upright and immediately search for/remove the triggering stimulus
D. Administer atropine
E. Begin CPR
F. Give a beta-blocker before examining the patient
Answer: C. Sit the patient upright and immediately search for/remove the triggering stimulus
Why: This is autonomic dysreflexia. Sitting upright helps reduce BP while the trigger—commonly bladder distention or bowel impaction—is identified and corrected.
A patient receiving unfractionated heparin develops a platelet count drop from 240,000 to 92,000 on day 7 and develops a new DVT. Which mechanism best explains this?
A. Direct bone marrow suppression
B. Autoimmune destruction of platelets unrelated to heparin
C. IgG antibodies against the PF4-heparin complex causing platelet activation
D. Vitamin K deficiency
E. Disseminated intravascular coagulation from excessive anticoagulation
F. Direct platelet toxicity from heparin
Answer: C. IgG antibodies against the PF4-heparin complex causing platelet activation
Why: Classic HIT = thrombocytopenia + thrombosis several days after heparin exposure. The key is that HIT is prothrombotic, not simply a bleeding disorder.
A 31-year-old G2P1 at 35 weeks presents with severe right upper-quadrant pain, nausea, headache, and visual changes.
Vital signs:
Labs:
Fetal monitoring shows recurrent late decelerations. Which combination represents the most appropriate overall management strategy?
A. Outpatient monitoring and oral antihypertensives
B. Magnesium sulfate only, with pregnancy continued until 39 weeks
C. Stabilization with magnesium sulfate and treatment of severe hypertension, followed by delivery
D. Methotrexate followed by delivery
E. Immediate aggressive fluid administration and expectant management
F. Platelet transfusion as the sole treatment
Answer: C. Stabilization with magnesium sulfate and treatment of severe hypertension, followed by delivery
Why: This patient has severe preeclampsia with HELLP syndrome, plus maternal organ dysfunction and nonreassuring fetal status.
The priorities are:
At 35 weeks with HELLP and maternal/fetal deterioration, continuing the pregnancy is dangerous.