Hyponatremia Diagnostic Algorithm | SIADH Workup & Pitfalls | Part 2

In Part 1 we built the physiological foundation. In Part 2, we turn it into action — a single systematic 4-step diagnostic algorithm that handles any hyponatremia presentation at the bedside. 🎓 WHAT YOU'LL LEARN IN THIS VIDEO The 4-step diagnostic algorithm — in order, every time Step 1: Confirming hyponatremia is real — ruling out pseudohyponatremia with direct ISE Step 2: Serum osmolality — the 3 buckets (hypotonic, isotonic, hypertonic) Step 3: Volume status assessment — the 4 clinical pillars (vitals, JVP & skin, urinary Na, clinical judgment) Step 4: Urine studies — osmolality, sodium & chloride read together, never in isolation The vomiting trap — why urinary sodium misleads and urinary chloride is the discriminator SIADH workup — exclusions (thyroid, cortisol, drugs) before applying Bartter & Schwartz criteria Reset osmostat — recognition, monitoring, and when not to treat Cerebral salt wasting vs SIADH — the clinical volume status is the key 6 algorithm pitfalls with examiner pearls 2 live cases walked through the full algorithm — Case 1 (78F, thiazide) and Case 2 (24F, vomiting) ⏱ CHAPTERS 0:00:00 Introduction & Series Recap 0:00:49 6 Key Takeaways from Part 1 0:02:48 The Master 4-Step Algorithm — Overview 0:03:51 Step 1 — Confirm Hyponatremia is Real 0:05:00 Pseudohyponatremia — Direct ISE Method 0:05:51 Step 2 — Serum Osmolality & Tonicity 0:07:13 Hypertonic Hyponatremia & Hillier's Correction 0:07:33 Step 3 — Volume Status Assessment 0:08:20 Urinary Sodium — The Branch Confirmer 0:09:27 Urinary Chloride — The Vomiting Trap Breaker 0:11:58 3 Hypotonic Branches — Hypo, Eu & Hypervolemic 0:14:29 Case 2 Setup — 24F with Vomiting & Diarrhoea 0:16:02 Case 2 — 4-Step Algorithm Applied 0:19:13 Euvolemic Algorithm — SIADH vs Primary Polydipsia 0:21:53 Reset Osmostat — Recognition & Management 0:22:01 Hypervolemic Algorithm — Low ECV Concept 0:23:36 Case 1 Returns — 78F on Thiazide 0:24:05 Case 1 — 4-Step Algorithm Applied 0:26:20 SIADH vs Thiazide — The Final Verdict 0:28:00 6 Algorithm Pitfalls 0:30:36 Algorithm Summary — 6 Steps to Memorise 0:32:08 Examiner Pearls — Top 3 0:33:30 Bridge to Part 3 — Management Preview 🩺 ABOUT THIS CHANNEL ClinicalMedEd is created by Dr. Raza Ali Akbar — Senior Consultant in Internal Medicine (Hamad General Hospital, Qatar), Clinical Associate Professor (Qatar University), Assistant Professor (Weill Cornell Medicine–Qatar), current MRCP UK PACES Examiner, former MRCP UK Question Author, and FRCP Edinburgh. Think. Learn. Heal. ⚖️ Disclaimer: Visuals: All images, graphics, audio and video assets are licensed stock media provided via Canva, unless otherwise attributed. Infographics/images: Some content created specifically for ClinicalMedEd. Medical: Strictly educational, not medical advice, no doctor-patient relationship. Practice: Follow local guidelines. 🔗 RELATED VIDEOS ▶ Hyponatremia Part 1 — Pathophysiology, Classification & Causes [   • Hyponatremia Explained | Pathophysiology, ...  ] ▶ Hyponatremia Part 3 — Hypertonic Saline, Safe Correction & ODS [coming soon] ▶ Acute Hyperkalemia — Causes, Diagnosis & Management [link] 📌 Diagnosis is half the work. Subscribe and hit the bell for Part 3 — safe correction rates, hypertonic saline, ODS, and overcorrection rescue. #hyponatremia #SIADH #internalmedicine #hyponatremiadiagnosis #usmle #MRCP #electrolyteimbalance #medicalstudent #clinicalmeded #diagnosticalgorithm #urinaryosmolality #urinarysodium #urinarychloride #paces #usmleStep2