How to correct hyperkalemia and metabolic acidosis?

Management of Severe Hyperkalemia with Metabolic Acidosis

For a potassium of 6.71 mEq/L with metabolic acidosis (HCO3- 13), immediately administer IV calcium gluconate 15-30 mL (or calcium chloride 5-10 mL) over 2-5 minutes for cardiac membrane stabilization, followed by insulin 10 units with 50 mL of 50% dextrose IV, and add sodium bicarbonate 50-100 mEq IV specifically because metabolic acidosis is present. 1, 2

Immediate Cardiac Stabilization (Within 1-3 Minutes)

• Administer IV calcium first to stabilize cardiac membranes, regardless of ECG findings at this potassium level 2, 3
• Calcium gluconate (10%): 15-30 mL IV over 2-5 minutes, OR calcium chloride (10%): 5-10 mL IV over 2-5 minutes 1
• Effects begin within 1-3 minutes but last only 30-60 minutes and do not lower potassium 1
• Obtain immediate ECG to assess for peaked T waves, flattened P waves, prolonged PR interval, or widened QRS 2, 3

Intracellular Potassium Shift (Within 15-30 Minutes)

Insulin/Glucose Therapy:

• Give 10 units regular insulin IV with 50 mL of 50% dextrose (25g glucose) 1, 2, 3
• Onset of action: 15-30 minutes; duration: 4-6 hours 1, 2
• Monitor glucose every 2-4 hours to prevent hypoglycemia 2
• Can repeat every 4-6 hours if hyperkalemia persists, with careful glucose monitoring 2

Beta-2 Agonist Therapy:

• Nebulized albuterol/salbutamol 10-20 mg in 4 mL over 15 minutes 1, 2
• Short duration of effect (2-4 hours), use as adjunctive therapy 1

Sodium Bicarbonate for Metabolic Acidosis

This patient specifically requires bicarbonate due to HCO3- of 13:

• Sodium bicarbonate is indicated ONLY in hyperkalemic patients with concurrent metabolic acidosis 1, 2
• Dose: 50-100 mEq IV over 5 minutes for severe cases 1, 2, 4
• The Mayo Clinic guidelines explicitly state bicarbonate promotes potassium elimination through increased distal sodium delivery and counters acidosis-induced potassium release 1
• Effects take 30-60 minutes to manifest 2, 3
• Bicarbonate lowers plasma potassium independent of pH changes by increasing urinary potassium excretion 5

Critical caveat: Do not use bicarbonate in patients without metabolic acidosis—it is contraindicated in that setting 2, 3

Potassium Removal from the Body

Loop Diuretics (if adequate renal function):

• Furosemide 40-80 mg IV to increase renal potassium excretion 1, 2
• Only effective if patient has residual kidney function and is non-oliguric 1

Hemodialysis:

• Most reliable and effective method for severe hyperkalemia, especially with renal failure 1, 6
• Consider urgently if oliguria, end-stage renal disease, or refractory to medical management 1, 2

Potassium Binders:

• Consider patiromer or sodium zirconium cyclosilicate for ongoing management 2, 3
• These facilitate definitive potassium removal but work more slowly 2

Monitoring Protocol

• Recheck potassium every 2-4 hours after initial treatment 2
• Continuous ECG monitoring until potassium <6.0 mEq/L 2, 3
• Monitor glucose closely to prevent hypoglycemia from insulin 2, 3
• Assess arterial blood gases to track acidosis correction 4

Common Pitfalls to Avoid

• Do not skip calcium administration—at K+ 6.71 mEq/L, cardiac membrane stabilization is critical even without ECG changes 2, 3
• Remember that calcium, insulin, and beta-agonists only temporize—they do not remove potassium from the body 2, 3
• Always give glucose with insulin to prevent life-threatening hypoglycemia 2, 3
• Do not withhold bicarbonate in this case—the presence of metabolic acidosis (HCO3- 13) makes it specifically indicated 1, 2
• Verify this is not pseudohyperkalemia from hemolysis or poor phlebotomy technique before aggressive treatment 2, 3

Identify and Address Underlying Causes

• Review medications: ACE inhibitors, ARBs, mineralocorticoid antagonists, NSAIDs, beta-blockers 2, 3
• Assess renal function and urine output 1
• Consider adrenal insufficiency, tissue breakdown, or excessive potassium intake 2