Pathophysiology & Risk Factors

Serum potassium above 5.0 mEq/L (normal 3.5-5.0). Potassium is the dominant intracellular cation, so excess extracellular K+ directly disrupts cardiac conduction and neuromuscular excitability. Risk rises whenever the kidneys cannot excrete K+, when drugs block its excretion, or when cells dump K+ into the blood.

Signs & Symptoms

EarlyProgresses →

muscle weakness

begins in the legs

paresthesia

tingling in extremities

abdominal cramping

hyperactive bowel sounds

GI smooth-muscle irritability

palpitations

Late / Severe

flaccid paralysis

cardiac dysrhythmias

Diagnostics & Labs

5.5 · Peaked T waves appear

Medical emergency

Low

Normal

Elevated

Critical / emergency

2.5

3.5

mEq/L

Interventions & Priorities

C-S-E sequence: Stabilize -> Shift -> Eliminate

Stabilize the heartIV calcium gluconate; onset 1-3 min, lasts 30-60 min; does NOT lower K+
Shift K+ into cellsregular insulin + dextrose, albuterol, bicarb if acidotic; onset 15-30 min
Eliminate from bodysodium polystyrene sulfonate, loop diuretics, hemodialysis

Treatments & Medications

IV calcium gluconate Hallmark

stabilizes cardiac membrane; does NOT lower K+

regular insulin

shifts K+ into cells; never rapid-acting analogs for this protocol

dextrose 50%

co-given with insulin to prevent hypoglycemia

nebulized albuterol

shifts K+ intracellularly

sodium bicarbonate

shifts K+ in if acidosis present

sodium polystyrene sulfonate

removes K+ via GI tract over hours

loop diuretics

if renal function allows

hemodialysis

definitive removal for refractory cases

Patient Teaching

limit high-potassium foods

bananas, oranges, potatoes, salt substitutes

avoid salt substitutes

potassium chloride based

report muscle weakness or palpitations

review potassium-raising medications

ACE inhibitors, ARBs, K-sparing diuretics, NSAIDs

adhere to dialysis schedule

missed sessions cause dangerous spikes

Report Nowescalate immediately

potassium > 6.0 mEq/LK+ > 6.0 mEq/L

medical emergency

peaked T waves

earliest ECG sign

widened QRS complex

absent P waves

atrial standstill

sine wave pattern

immediate pre-arrest rhythm

persistent ECG changes despite treatment

inadequate response — escalate to dialysis

insulin-induced hypoglycemiaglucose < 70 mg/dL

risk persists 4-6 h post-dose; give dextrose

Clinical Pearl

C-S-E: Cardiac stabilization first (calcium buys minutes), Shift second (insulin + glucose buys hours), Eliminate last (Kayexalate or dialysis solves it). Calcium protects the heart but never lowers the potassium.