Hyperkalaemia = Elevated potassium levels in the blood (K⁺ > 5.5 mmol/L). It can cause profound cardiac conduction abnormalities and life-threatening arrhythmias if untreated. 🚨

📉 ECG Features of Hyperkalaemia

🔺 Peaked T Waves: Earliest sign – tall, narrow, "tented" T waves.
❌ Absent P Waves: Loss of atrial activity as potassium rises.
📏 Broad QRS Complex: Progressive widening; red flag for impending arrest.
〰️ Sine Wave Pattern: Fusion of QRS and T ➝ pre-terminal sign.
🐢 Bradycardia: Slowed rate due to impaired conduction.
💔 Agonal Rhythm ➝ Asystole: Final rhythm before cardiac standstill.
⚠️ Cardiac Arrest: High risk of VF/VT, PEA, or asystole.

📊 ECG Progression (Potassium Levels)

Serum K⁺ (mmol/L)	ECG Change
5.5 – 6.5	Peaked T waves, shortened QT interval
6.5 – 7.5	P wave flattening, PR prolongation
7.5 – 8.5	QRS widening, sine-wave begins
> 8.5	Ventricular fibrillation, asystole

📸 ECG Example

Hyperkalaemia on ECG: Tall peaked T waves with broad QRS complexes.

⚡ Emergency Management of Hyperkalaemia

1️⃣ Stabilise Myocardium
- IV Calcium Gluconate 10% (10 mL over 2–5 min).
- Notes: Acts within minutes; protects the heart but does not lower serum K⁺.
2️⃣ Shift K⁺ Into Cells
- IV Insulin (10 units Actrapid + 50 mL 50% dextrose).
- Nebulised Salbutamol 10–20 mg.
- IV Sodium Bicarbonate (if metabolic acidosis present).
- Notes: Onset within 15–30 min; effect is temporary.
3️⃣ Remove K⁺ From Body
- Loop diuretics (if volume replete).
- Calcium resonium (slow action).
- Haemodialysis → definitive if refractory or renal failure.
- Notes: Provides permanent removal of potassium.
4️⃣ Monitor
- Continuous ECG monitoring.
- Repeat K⁺ every 1–2 hours.
- Look for recurrent rises or ongoing causes.

🔍 Key Clinical Pearls

Always treat the ECG, not the number ➝ a patient with ECG changes and K⁺ 6.0 mmol/L is more urgent than one with K⁺ 7.0 mmol/L and a normal ECG.
Check and stop contributing drugs (e.g., ACE inhibitors, ARBs, spironolactone). 💊
Common in renal failure, acidosis, tissue breakdown (e.g., rhabdomyolysis, tumour lysis). 🧪

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ECG - Hyperkalaemia

⚡ Overview

📉 ECG Features of Hyperkalaemia

📊 ECG Progression (Potassium Levels)

📸 ECG Example

⚡ Emergency Management of Hyperkalaemia

🔍 Key Clinical Pearls

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