A 50 years old female patient who was on losartan and spironolactone therapy for her hypertension developed hypotension and bradycardia. The ECG taken is as below. Effective treatment for her
High-Yield Explanation
Answer: c) IV calcium gluconate followed by IV sodium bicarbonateHYPERKALEMIAPlasma K+ concentration > 5.5 mmol/LPseudohyperkalemiaCellular efflux: thrombocytosis, erythrocytosis, leukocytosis, in vitro hemolysisHereditary defects in red cell membrane transport* Renal failure* | distal flow (| effective circulating volume)* Tubular secretory failure (| K+ secretion) * Impaired Na reabsorption(1deg,2degand pseudohypoaldosteronism)* |chloride reabsorption(Gordon's yndrome, cyclosporine)Drugs* ACE inhibitors* Amiloride* Cytotoxic drugs* Digitalis overdose* Heparin* Lithium* NSAIDs* Pentamidine* Spironolactone* Succinyl choline* TriamtereneEarly ECG changes of hyperkalemia (Serum potassium level 5.5-6.5 mEq/L)Tall, peaked T waves with a narrow base, best seen in precordial leadsShortened QT intervalST-segment depressionSerum potassium level of 6.5-8.0 mEq/LPeaked T wavesProlonged PR intervalDecreased or disappearing P waveWidening of the QRSAmplified R waveSerum potassium level higher than 8.0 mEq/LAbsence of P waveProgressive QRS wideningIntraventricular/fascicular/bundle branch blocksThe progressively widened QRS eventually merges with the T wave, forming a sine wave pattern. Ventricular fibrillation or asystole follows.Treatment of Hyperkalemia: indicated if the plasma K+concentration exceeds 6.5 mmol/l.Immediate antagonism of the cardiac effects of hyperkalemia (Stabilize cell membrane potential)I.V. calcium gluconateRapid reduction in plasma K+ concentration by redistribution into cells.* Inhale b2 agonist (salbutamol)* I.V. glucose (50ml of 50% solution) and insulin (5U Actrapid)Shift K+ into cells but no role in acute hyperkalemiaI.V. sodium bicarbonateRemove K+ from body* I.V. furosemide and NS* Cation-exchange resins (sodium polystyrene sulfonate-SPS) orally or rectally* Hemodialysis - most effective and reliable method