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]
