Renal: Hypokalaemia: Free MSRA Podcast

⚡ FREE MSRA PODCAST – Hypokalaemia🎧 A clear, high-yield breakdown of this common and potentially life-threatening electrolyte disturbance – perfect for exam prep and real-life clinical scenarios.🧠 Key Learning Points📌 Definition• Hypokalaemia refers to low blood potassium – defined as <3.5 mmol/L• Categorised by severity:– Mild: 3.1–3.5 mmol/L– Moderate: 2.5–3.0 mmol/L– Severe: <2.5 mmol/L• Even mild cases increase cardiac arrhythmia risk 💓📌 Causes & Risk Factors• Renal losses: loop/thiazide diuretics, hyperaldosteronism (e.g. Conn’s), renal tubular acidosis• GI losses: diarrhoea, vomiting, laxative abuse, bowel fistulae• Skin losses: burns, profuse sweating• Transcellular shift: insulin + glucose (e.g. DKA treatment), alkalosis, salbutamol use• Reduced intake: malnutrition, anorexia, prolonged IV fluids without K⁺• Miscellaneous: alcohol misuse, peritoneal dialysis• Congenital: Gitelman’s and Bartter’s syndromes🧠 Mnemonic: “DISH” – Diuretics, Intake ↓, Shifts, Hyperaldosteronism📌 Pathophysiology• 98% of potassium is intracellular• Only 2% in extracellular fluid (what we measure)• Na⁺/K⁺ ATPase pump maintains this gradient• Kidneys (regulated by aldosterone) control K⁺ excretion• Losses or shifts lead to impaired membrane potential → muscle + cardiac issues📌 Symptoms• Often asymptomatic if mild• Moderate: fatigue, muscle weakness, constipation• Severe: paralysis, respiratory muscle weakness, arrhythmias• Other signs: muscle cramps, palpitations, polyuria• Important risk: digoxin toxicity🧠 Always check K⁺ in elderly or those on diuretics/digoxin!📌 Differential Diagnosis• Diuretic overuse• Diarrhoea or vomiting• DKA treatment (insulin shift)• Primary hyperaldosteronism• Anorexia, malnutrition• Bartter’s/Gitelman’s syndromes• Renal tubular disorders📌 Diagnosis• Bloods: U&Es (confirm low K⁺), serum magnesium, bicarbonate, glucose, chloride• Check Mg²⁺: must be corrected for proper K⁺ repletion• ECG:– Flattened T waves– ST depression– U waves– Risk of ventricular arrhythmias if <3.0 mmol/L• Urine potassium:– Low urine K⁺ → GI loss or transcellular shift– High urine K⁺ → renal loss• Urine sodium: low Na⁺ + high K⁺ may indicate volume depletion• Further: renin/aldosterone, cortisol, adrenal imaging for endocrine causes📌 Management• Treat underlying cause and replace potassium• Mild (3.1–3.5):– Oral K⁺ supplements (e.g. KCl), dietary advice (bananas, tomatoes 🥑🍌🍅)– Monitor levels regularly• Moderate (2.5–3.0):– Urgent review, oral or IV K⁺ replacement, assess cause• Severe (<2.5):– Hospital admission, IV potassium chloride (monitor cardiac rhythm)– May need central line for high doses• Always correct magnesium concurrently• Avoid combining K⁺-sparing diuretics + supplements (risk of hyperkalaemia)• Prevention:– Consider spironolactone or amiloride with high-dose diuretics– Regular monitoring in at-risk groups📌 Complications• Cardiac arrhythmias – esp. in those on digoxin• Rhabdomyolysis• Paralysis, respiratory compromise• Nephrogenic diabetes insipidus• Metabolic alkalosis• Hepatic encephalopathy (in cirrhosis)• Iatrogenic hyperkalaemia if overcorrected📌 Prognosis• Good if recognised early and managed appropriately📎 More MSRA Resources📝 Revision Notes:https://www.passthemsra.com/topic/hypokalaemia-revision-notes/🧠 Flashcards:https://www.passthemsra.com/topic/hypokalaemia-flashcards/💬 Accordion Q&A Notes:https://www.passthemsra.com/topic/hypokalaemia-accordion-qa-notes/🚀 Rapid Quiz:https://www.passthemsra.com/topic/hypokalaemia-rapid-quiz/🎓 Full Course:https://www.passthemsra.com/courses/renal-for-the-msra/#MSRA #MSRARevisionNotes #MSRATextbook #MSRAQuiz #MSRAQuestionBank #MSRAFlashcards #MSRAQANotes #MSRAAccordions #MultiSpecialityRecruitmentAssessment #MSRAOnlineRevision #MSRARevisionWebsite #Renal #Hypokalaemia