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 correction

Press play and master potassium - one stem at a time.

Every clinician has encountered a case that doesn’t quite fit—where the usual explanations fall short and the clues refuse to line up. In this Zebra of the Month episode, we invite you into a diagnostic puzzle that challenges assumptions and rewards careful, deliberate thinking.

With no spoilers and no shortcuts, we unravel the case step by step, highlighting the moments of uncertainty, the subtle details that matter, and the reasoning that keeps rare diagnoses from slipping through the cracks. This episode is about staying curious when the answer isn’t obvious and trusting the process when the path forward feels unclear.

If you enjoy clinical suspense, unexpected turns, and the art of diagnostic reasoning, this is an episode you won’t want to miss!

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 minute
• Use volume status and urine studies to pinpoint the cause
• Recognize classic vignettes like SIADH, cerebral salt wasting, and adrenal insufficiency
• Avoid the most dangerous board trap: osmotic demyelination syndrome

Helpful links for more info:

https://www.ninjanerd.org/podcast/hyponatremia/

https://emcrit.org/pulmcrit/hyponatremia-2/

Sepsis is one of the most common and deadly emergencies you’ll encounter on boards and in clinical practice. In this episode of One Stem at a Time, we break down sepsis from start to finish: what it is, how the body responds, and when it turns into septic shock. Learn the key mechanisms behind systemic inflammation, the classic clinical clues that signal organ dysfunction, and the stepwise management strategy that saves lives. By the end of this episode, you’ll be able to recognize sepsis, understand its pathophysiology, and recall the high-yield treatment priorities that boards love. Perfect for rapid review and clinical reasoning reinforcement.

High-Yield Takeaways Include:

• Understanding the dysregulated host response to infection

• Differentiating sepsis from septic shock

• Prioritizing time-critical interventions: fluids, antibiotics, vasopressors, and source control

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.

Every clinician has encountered a case that doesn’t quite fit—where the usual explanations fall short and the clues refuse to line up. In this Zebra of the Month episode, we invite you into a diagnostic puzzle that challenges assumptions and rewards careful, deliberate thinking.

With no spoilers and no shortcuts, we unravel the case step by step, highlighting the moments of uncertainty, the subtle details that matter, and the reasoning that keeps rare diagnoses from slipping through the cracks. This episode is about staying curious when the answer isn’t obvious and trusting the process when the path forward feels unclear.

If you enjoy clinical suspense, unexpected turns, and the art of diagnostic reasoning, this is an episode you won’t want to miss!

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.

In this episode, we take a deep dive into non–anion gap metabolic acidosis (NAGMA) and renal tubular acidosis (RTA)—topics that are high-yield for exams and essential for clinical reasoning. We break down the different types of RTA (Type I, II, and IV), walk through the full differential diagnosis for NAGMA, and explain how to distinguish these entities using labs you’re likely to see on test day. You’ll also learn the core treatment strategies for each type of RTA and review classic associations and buzzwords that commonly show up on board questions. Whether you’re studying for exams or solidifying your acid–base fundamentals, this episode will help you turn a confusing topic into a clear, testable framework.

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.

Join us for an in-depth discussion on key respiratory physiology and pathology topics. In this episode, we break down the mechanisms behind COPD, the physiology of airway obstruction in asthma exacerbations, and how acid-base balance is affected in respiratory disease. We also explore the pathophysiology of ARDS and its impact on lung compliance, review how to calculate and interpret the A–a gradient, and unpack the underlying defects in Kartagener syndrome. Perfect for medical students, residents, or anyone looking to strengthen their understanding of pulmonary physiology and clinical correlations.