One Stem at a Time: High-Yield Board Review for Medical Students

Obstructive shock is one of the most testable—and most misunderstood—shock states on boards and in clinical medicine. In this episode of One Stem at a Time, we break it down from first principles so you can stop memorizing arrows and start understanding them.Through two classic board-style cases—cardiac tamponade and pulmonary embolism—you’ll learn how to recognize obstructive shock, interpret hemodynamic profiles, and confidently work through “arrow questions” involving cardiac index, right atrial pressure, pulmonary capillary wedge pressure, and systemic vascular resistance.We focus on building a simple, powerful framework: follow the flow of blood, identify where it’s blocked, and let the physiology guide you. Along the way, we highlight key distinctions between tamponade, tension pneumothorax, and massive PE, explain why SVR is increased (even in hypotensive patients), and review how PCWP is measured and applied clinically.By the end of this episode, you’ll be able to:Recognize obstructive shock from clinical presentations and exam cluesUnderstand the underlying pathophysiology and compensatory mechanismsInterpret hemodynamic “arrow” questions with confidenceDifferentiate tamponade, pulmonary embolism, and tension pneumothoraxApply high-yield board strategies and clinical reasoning in real timePerfect for USMLE and COMLEX prep, clinical rotations, and rapid review before exams.

In this episode, we break down carcinoid syndrome from the ground up, starting with its underlying pathophysiology—how neuroendocrine tumors produce excess serotonin and other vasoactive substances that drive the disease.We then walk through the key symptoms, including flushing, diarrhea, and bronchospasm, connecting each one back to what’s happening at a biochemical level. From there, we explore complications, including pellagra, and explain how tryptophan depletion leads to this often-overlooked condition.Next, we shift into management, focusing on the role of octreotide and how it helps control symptoms and prevent progression. We also cover carcinoid crisis, a life-threatening escalation of the disease, discussing common triggers and the importance of rapid recognition and treatment.Finally, we wrap up with long-term complications, including carcinoid heart disease and its classic association with tricuspid regurgitation, tying everything back to the systemic effects of prolonged serotonin exposure.This episode offers a cohesive, clinically relevant look at carcinoid syndrome—from mechanism to management to complications.

Jaundice questions don't have to be confusing. In this rapid review, we break down bilirubin metabolism and classic disorders you'll see on exams: Gilbert, Cringler-Najjar, Dubin-Johnson, and Rotor Syndrome. Learn how to quickly distinguish between unconjugated vs conjugated hyperbilirubinemia and lock in the diagnosis in seconds.One stem. One diagnosis. No guesswork.

In this high-yield episode of One Stem at a Time, we break down hyperkalemia the way board exams (and real patients) demand you understand it.We walk step-by-step through the physiology of potassium, the classic EKG progression from peaked T waves to sine wave arrest, and the exact treatment algorithm you need to know for exams and the wards. Then we tackle one of the most commonly tested (and most dangerous) clinical pitfalls: potassium management in diabetic ketoacidosis (DKA).By the end of this episode, you’ll be able to recognize hyperkalemia instantly, treat it in the correct order under pressure, and avoid the classic DKA potassium mistake that trips up students and residents alike.Perfect for: medical students, COMLEX/USMLE prep, and early residents. Topics covered include hyperkalemia physiology, EKG changes, emergent treatment, insulin effects on potassium, and DKA potassium correctionPress play and master potassium - one stem at a time.

Hyponatremia is one of the most tested — and most misunderstood — electrolyte disorders. This episode breaks it down into a clear algorithm using volume status, osmolality, and urine studies so you can solve hyponatremia questions with confidence on exams and on the wards.You’ll learn how to:Distinguish real vs “fake” hyponatremia in under a minuteUse volume status and urine studies to pinpoint the causeRecognize classic vignettes like SIADH, cerebral salt wasting, and adrenal insufficiencyAvoid the most dangerous board trap: osmotic demyelination syndromeHelpful links for more info:https://www.ninjanerd.org/podcast/hyponatremia/https://emcrit.org/pulmcrit/hyponatremia-2/

Sometimes cancer announces itself in unexpected ways—through weakness, electrolyte abnormalities, rashes, or blood clots rather than a visible tumor. In this episode of One Stem at a Time, we break down the high-yield paraneoplastic syndromes you need to recognize on exams, from Lambert-Eaton and myasthenia gravis to SIADH, ectopic ACTH, dermatomyositis, Trousseau syndrome, and hypercalcemia of malignancy. We focus on classic presentations, key cancer associations, underlying mechanisms, and board-ready pearls to help you spot the diagnosis fast when the symptoms don’t seem to fit.

Pleural effusions are common, but working through them systematically can be challenging. In this episode, we take a deep dive into pleural fluid analysis, starting with a clear and practical breakdown of Light’s criteria and how it’s used to differentiate transudative from exudative effusions. We review the key laboratory values, common pitfalls, and why these criteria remain so central to clinical decision-making.From there, we explore the major etiologies of transudates and exudates, linking physiology and pathology to real-world causes such as heart failure, infection, malignancy, and inflammatory disease. Throughout the discussion, we emphasize clinical reasoning—showing how to synthesize history, imaging, and lab results to arrive at a thoughtful diagnosis.Whether you’re a student learning pleural effusions for the first time or looking to reinforce a structured approach, this episode aims to make pleural fluid analysis more intuitive, practical, and clinically meaningful.

Chest pain can range from benign to immediately life-threatening, and missing the dangerous causes can be fatal. In this episode, we break down the 6 deadly causes of chest pain every clinician must recognize: acute coronary syndrome (ACS), pulmonary embolism (PE), esophageal perforation, aortic dissection, pericardial tamponade, and tension pneumothorax.We walk through how each condition presents, the key physiologic mechanisms driving the symptoms, and the high-yield clues to look out for. Using a practical, bedside approach, we compare management strategies in stable vs. unstable patients, highlighting when to slow down for diagnostics and when to act immediately.Whether you’re in the ED, ICU, on the wards, or preparing for exams, this episode ties pathophysiology directly to decision-making, helping you recognize red flags, prioritize interventions, and avoid catastrophic misses.

In this episode, we dive into inflammatory bowel disease (IBD) and autoimmune conditions affecting the gastrointestinal tract. We break down the key differences and overlaps between Crohn’s disease and ulcerative colitis (UC), and explore how chronic inflammation can impact nutrient absorption (especially vitamin B12 deficiency). We also discuss primary sclerosing cholangitis (PSC), a serious autoimmune liver condition often associated with UC, and why early recognition and monitoring matter.Whether you’re living with IBD, supporting someone who is, or looking to better understand the autoimmune processes behind these conditions, this episode offers clear explanations, clinical insight, and practical takeaways.