Source / episode info

• **Episode:**659
• **Title:**DIP Ep 659: USMLE Step 2/3 Review Series 138
• **Published:**2026-06-11
• Source:Episode page

One-liner

This episode provides a rapid review covering high-yield board topics including High D Syndrome (AS + GI bleed), acquired coagulopathies (ATIII deficiency), cardiac tamponade workup, STEMI equivalents, cor pulmonale pathophysiology, aortic dissection signs, acid-base gas analysis in overdose, and the differentiation of pleural effusions.

High-yield summary

• High D Syndrome: Triad of Aortic Stenosis + GI bleeding; caused by calcific valves degrading von Willebrand Factor (vWF), leading to impaired primary hemostasis. Management requires valve replacement.
• Cardiac Tamponade Workup: Look for hypotension, muffled heart sounds, and potentially deceptively normal/low Jugular Venous Pressure (JVP) in the setting of trauma or volume depletion; ECG may show short QRS complexes. Pericardiocentesis is therapeutic.
• Cor Pulmonale vs LHF: Cor pulmonale is Right Heart Failure secondary to a pulmonary cause (e.g., COPD, CF, OSA). Unlike Left Heart Failure (LHF), it typically does not present with crackles/pulmonary edema initially.
• Aortic Dissection: Type A dissection requires immediate surgical intervention; classic signs include severe chest pain and new diastolic murmur of aortic regurgitation, often associated with a wide pulse pressure.
• Pleural Effusion Classification: Transudates are due to systemic pressure or albumin imbalance (e.g., CHF, hypoalbuminemia). Exudates are due to local inflammation/infection (e.g., pneumonia, ARDS). Complicated parapneumonic effusions require drainage in addition to antibiotics.
• Hypoventilation Gas Analysis: In overdose causing hypoventilation, the A-a gradient is normal because the lung parenchyma is intact; the problem is reduced respiratory drive. Expect high PCO2 and low PaO2/PBO2 ratio.

Learning objectives

• Differentiate between various causes of acquired coagulopathy and their specific management interventions.
• Recognize the classic signs and pathophysiology of cardiac tamponade in a trauma setting.
• Apply knowledge of right heart failure (Cor Pulmonale) versus left heart failure, particularly in chronic lung disease.
• Interpret ECG findings and biomarkers to diagnose acute coronary syndromes, including STEMI equivalents.
• Analyze gas exchange data (A-a gradient, PCO2) to determine the primary cause of hypoxemia/acidosis.