II. Causes: Decreased Renal Excretion
- Hypoaldosteronism
- Hyporeninemic hypoaldosteronism
- Intrinsic renal disease (provoked by Dehydration)
- Prostaglandin synthetase inhibitors
- Primary Hypoaldosteronism
- Medication-induced hypoaldosteronism
- See medications below
- Adrenal Insufficiency (volume low, decreased GFR)
- Hyporeninemic hypoaldosteronism
- Decreased distal renal flow
- Hypovolemia
- Renal Insufficiency or Renal Failure
- Congestive Heart Failure
- Congestive Heart Failure
- Decreased distal nephron Sodium delivery
- Primary tubular defects
- Renal Tubular Acidosis (Type 4)
- Obstructive uropathy
- Tubular unresponsiveness to Aldosterone
- Medications
- See BRASH Syndrome
- Medication-induced hypoaldosteronism
- Heparin
- Cyclosporine
- ACE Inhibitor or Angiotensin Receptor Blocker
- Responsible for 50% of medication induced Hyperkalemia
- Concurrent trimethoprim-sulfamethoxazole increases risk (especially age>66)
- Risk of Hyperkalemia within the first year of starting ACE/ARB: 10%
- Raebel (2012) Cardiovasc Ther 30(3): e156-66 +PMID:21883995 [PubMed]
- Aldosterone Antagonists
- Potassium sparing Diuretics (e.g. Spironolactone)
- Other medications
- NSAIDS
- Lithium
- Trimethoprim
- Calcineuron inhibitors (e.g. Tacrolimus)
- Heparin
- Beta Blockers
III. Causes: Transcellular Shift or Redistribution (ICF to ECF)
- Metabolic Acidosis (more likely with mineral acids NH4, HCl)
- Hyperkalemic periodic paralysis
- Insulin deficiency or resistance (Diabetes Mellitus)
- Rapid ECF rise
- Hemodialysis
- Coronary bypass
- Cell lysis
- Any significant cause of cell turnover releases significant Potassium
- 98% of body Potassium is intracellular
- Rhabdomyolysis
- Tissue necrosis, severe Burn Injury or crush injury
- Tumor Lysis Syndrome (e.g. severe Hemolytic Anemia)
- Massive Hemolysis
- Surgery
- Gastrointestinal Bleeding
- Red Blood Cell Transfusion
- Any significant cause of cell turnover releases significant Potassium
- Hypertonicity
- Medications
- Succinylcholine (if concurrent tissue damage)
- Beta Blockers
- Digitalis Intoxication (Digoxin Toxicity)
- Arginine
- Somatostatin
IV. Causes: Potassium Load
- Oral or IV Potassium Supplementation
- High Dietary Potassium intake rarely causes Hyperkalemia in patients with normal Renal Function
- See Foods with High Potassium Content
- Salt substitute
- Protein calorie supplements
- Total Parenteral Nutrition
- Enteral feeding with high Potassium load
- Blood Transfusion (pRBC transfusion)
- High dose Penicillin G (1.7 meq K+ per 1 Million Units)
V. Causes: Pseudohyperkalemia (actual Serum Potassium less than lab reported value)
- Blood sample clotted or cooled
- Delayed analysis or other lab error
- Familial Pseudohyperkalemia
-
Hemolysis
- Excessive Tourniquet or fist clenched repeatedly
- Hemolysis via small needle or Traumatic venipuncture
- Severe blood cell hyperplasia
- Severe Thrombocytosis (>500,000/mm3)
- Severe Leukocytosis (>75,000/mm3)
VI. References
- Gibbs in Marx (2002) Rosen's Emerg Med, p. 1730-1
- Klahr (2001) in Noble (2001) Primary Care p. 1359-62
- Kim (2023) Am Fam Physician 107(1): 59-70 [PubMed]
- Viera (2015) Am Fam Physician 92(6): 487-95 [PubMed]