Hyperkalemia: Difference between revisions

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==Background==
==Background==
*Defined as >5.5 mEq/L
*Potassium secretion is proportional to flow rate and sodium delivery through distal nephron
**Thus, loop & thiazide [[diuretics]] cause ''hypo''kalmia
*Most common cause is hemolysis from blood draw (pseudohyperkalemia)


===Medication Causes===
====Alter transmembrane potassium movement====
*[[β blockers]]
*[[Digoxin]]
*Potassium-containing drugs
*Potassium supplements
*Salt substitutes
*Hyperosmolar solutions ([[mannitol]], [[dextrose|glucose]])
*Suxamethonium
*Intravenous cationic amino acids
*Stored [[pRBCs|red blood cells]] (haemolysis releases potassium)
*Herbal medicines (such as alfalfa, dandelion, horsetail, milkweed, and nettle)


High = >5.5meq/L
====Reduce aldosterone secretion====
*[[ACE inhibitors]]; [[Angiotensin II receptor blockers]]
*[[NSAIDs]]
*[[Heparin]]
*[[Antifungals]] ([[ketoconazole]], [[fluconazole]], [[itraconazole]])
*[[Cyclosporine]]
*[[Tacrolimus]]


High! = >6.5meq/L
====Block aldosterone binding to mineralocorticoid receptors====
*[[Spironolactone]]
*[[Eplerenone]]
*[[Drospirenone]]
*Potassium sparing [[diuretics]] (amiloride, triamterene)
*[[Trimethoprim]]
*[[Pentamidine]]


==Clinical Features==
 
''Typically non-specific''
==Diagnosis==
*[[Muscle weakness]]
 
*[[Lethargy]], [[fatigue]]
 
*[[Paresthesias]]
Always consider pseudohyperkalemia (e.g. from hemolysis)
*[[Nausea and Vomiting]]
 
*[[Difficulty breathing]]
=== ===
*[[Palpitations]], [[chest pain]]
 
 
===ECG===
 
 
6.5 - peaked Ts, inc PR, dec QT
 
7.5 - QRS widening, P flattening
 
8 - sine wave, v-fib, heart block
 


==Differential Diagnosis==
==Differential Diagnosis==
{{Hyperkalemia DDX}}
{{Peaked T-waves DDX}}
{{Tachycardia (wide) DDX}}


==Evaluation==
[[File:PMC4475259 JCHIMP-5-27993-g003.png|thumb|Diagrammatic representation of ECG changes with increasing hyperkalemia]]
[[File:HyperK2014.jpg|thumb|ECG in hyperkalemia with peaked T waves and small P waves]]
[[File:PMC4475259 JCHIMP-5-27993-g001.png|thumb|ECG with widened QRS complex and tall broad T waves]]
[[File:PMC4475259 JCHIMP-5-27993-g005.png|thumb|ECG showing sine wave pattern]]
===Workup===
*[[ECG]]
*Chem 10 (including potassium, magnesium, and phosphorus)
**Consider point-of-care lab testing for more rapid result
*Consider [[ABG]]/[[VBG]] to evaluate pH


A. Redistribution
===[[ECG]]===
 
''Changes NOT always predictable and sequential''
    1. Acidosis drives potassium out of the cells
*6.5 - 7.5 mEq/L: peaked T waves, prolonged PR interval, shortened QT interval
 
*7.5 - 8.0 mEq/L: widened QRS interval, flattened P waves
      a.  DKA
*10 - 12 mEq/L: sine wave, ventricular fibrillation, heart block
 
    2. Cellular breakdown
 
      a. Rhabdomyolysis
 
      b. Hemolysis
 
      c. Tumor lysis syndrome
 
      d.  Crush
 
B. Increased total body potassium
 
    1. Inadequate excretion
 
      a. Renal caused (acute or chronic renal failure-must have GFR<10)
 
      b. Mineralocorticoid deficiency or Addison's disease
 
      c. Drug-induced (potassium sparing diuretics [e.g., spironolactone] and ACE-inhibitors)
 
    2. Excessive intake
 
      a. Diet, meds
 
      b. Blood transfusion
 
C. Pseudohyperkalemia
 
    1. Hemolysis of the specimen
 
    2. Prolonged period of tourniquets occlusion prior to blood draw
 
    3. Thrombocytosis/leukocytosis
 
D. Misc
 
    1.  Succs, dib, B-blockers
 
 
==Treatment==


===Diagnosis===
*Based on lab testing (>5.5 mEq/L), although ECG may provide earlier information
*Consider pseudohyperkalemia (e.g. from hemolysis)


==Management==
===Stabilize cardiac membranes===
''Indicated if there are any ECG changes or evidence of arrhythmias. Consider if K >7 mEq/L''
*Either one of the following:
**[[Calcium gluconate]]: Give 10ml of a 10% solution (1 gram) over 5-10 mins. In severe cases may have to start with higher dose of 3 grams (30 mLs) and repeat doses (up to 9-15 grams total).
***Only 1/3 the elemental calcium compared to calcium chloride.
***Can cause hypotension due to osmotic shift
**[[Calcium chloride]] 1 gram IV
***Give over 1 - 2 minutes
***Extravasation is bad: use a good IV
***Usually given in code situations
*Takes effect in 15-30 minutes<ref>http://lifeinthefastlane.com/hyperkalemia/. Accessed 02/22/2016</ref>
**(If given for hyperkalemic cardiac arrest, need to continue resuscitation for at least 30 minutes)
*Duration of action: 30 - 60 minutes <ref> The Effect of Calcium on Severe Hyperkalemia http://hqmeded-ecg.blogspot.com/2015/04/the-effect-of-calcium-on-severe.html</ref>
*Use caution in patients taking [[Digitalis Toxicity|Digoxin]] although risk of [[Stone heart]] may be unsubstantiated <ref>Erickson CP, Olson KR. Case files of the medical toxicology fellowship of the California poison control system-San Francisco: calcium plus digoxin-more taboo than toxic? J Med Toxicol. 2008 Mar;4(1):33-9</ref>
*Do serial [[ECG]]s to track progress: may need to give multiple doses


* Calcium gluconate 1 amp IV (if ECG changes/hypotension/or >7; can give mult times)
===Shift K+ intracellularly===
* Caution in dig-toxic patients!
*Intravenous [[insulin]] + [[dextrose]]
* Albuterol neb 2.5mg x 3
**Give 10 units regular insulin intravenously with 25 to 50 grams (1 - 2 50 mL ampules) of 50% dextrose (D50)
* 10 U reg insulin IV with 1 amp D50W IV now, and 1 amp in 15 min
***May withhold dextrose if blood sugar >300mg/dl (>17 mmol/L)
* 1 amp NaBicarb IV (over 5 min)
***Duration of effect: 4 - 6 hours
* Kayexalate 30g PO (may cause volume overload; +/- 50mL sorbitol)
***Consider mixing in 10 cc NS syringe to ensure small volume of 10 units insulin fully administered via IV
* Consider dialyisis & ?lasix
***Insulin cleared renally, be careful about inducing hypoglycemia (ESRD patients).  
****In a [https://onlinelibrary.wiley.com/doi/abs/10.1002/phar.2038 small 2017 retrospective cohort study], researchers found that giving 5 units of insulin instead of 10 units reduced serum potassium to the same extent as 10 units, with a lower rate of hypoglycemia.
****Consider decreasing to 5 units or increasing dextrose dose to 50g with following risk factors: pretreatment blood glucose <150, acute kidney injury/chronic kidney disease, no history of DM, weight <60kg, female sex <ref> Moussavi K1, Fitter S2, Gabrielson SW3, Koyfman A4, Long B5. Management of Hyperkalemia With Insulin and Glucose: Pearls for the Emergency Clinician. J Emerg Med. 2019 Jul;57(1):36-42. </ref>
*Nebulized [[albuterol]] 15 - 20mg
**Response is dose-dependent
**Peak effect: 30 minutes
**Duration of effect: 2 hours
*[[Sodium bicarbonate]]
**Generally not considered unless pH <7.1
**Pushing "ampules of hypertonic bicarbonate have been proven to be ineffective in RCTs"<ref>[https://emcrit.org/ibcc/hyperkalemia/ IBCC Hyperkalemia Chapter]</ref>
**For '''normovolemic or hypovolemic''' patients with '''metabolic acidosis''':
***Give three amps of bicarbonate in a liter of D5W or sterile water


==Source ==
===Remove K+ from body===
*Intravenous [[furosemide]] (Lasix) 40 - 80mg
**Ensure adequate urine output first
**Decreases the potassium in three ways: dilution, shifting of potassium into muscle cells, and promotion of renal potassium excretion by alkalosis<ref>[https://emcrit.org/ibcc/hyperkalemia/ IBCC Hyperkalemia Chapter]</ref>
**More on how to use Lasix: [https://emcrit.org/ibcc/hyperkalemia/ IBCC Hyperkalemia Chapter]
*[[Sodium polystyrene sulfonate]] (Kayexalate): 30 gm oral or per rectum
**'''Very Controversial, High Risk of Bowel Perforation''', see: [[EBQ: Use of Kayexylate in Hyperkalemia]]
*[[Sodium zirconium cyclosilicate]] (Lokelma)
**Potassium binder, similar to [[Sodium polystyrene sulfonate|Kayexalate]] but without risk of bowel perforation<ref>Beccari, Mario V, and Calvin J Meaney. “Clinical utility of patiromer, sodium zirconium cyclosilicate, and sodium polystyrene sulfonate for the treatment of hyperkalemia: an evidence-based review.” Core evidence vol. 12 11-24. 23 Mar. 2017, doi:10.2147/CE.S129555</ref>
**10 mg PO TID for up to 48 hours, then 10-15 mg PO QD for maintenance
*Intravenous lactated ringers solution for volume expansion if dehydrated, rhabdomyolysis, diabetic ketoacidosis or other acidosis (avoid NS, causes hyperchloremic acidosis which shifts potassium out of cells increasing level)
**consider isotonic bicarbonate if significant acidosis (D5W with 3 amps of bicarb per liter), can calculate bicarbonate deficit then divide by 150mEq/L to estimate number of liters of isotonic bicarbonate required) <ref> https://emcrit.org/pulmcrit/fluid-selection-using-ph-guided-resuscitation </ref>
*[[Hydrocortisone]] if suspicious for [[adrenal insufficiency]]
*Definitive treatment is [[hemodialysis]]


===IV Fluid Choice===
*LR is preferred over NS, even in renal failure<ref>O'Malley CM, Frumento RJ, Hardy MA, Benvenisty AI, Brentjens TE, Mercer JS, Bennett-Guerrero E. A randomized, double-blind comparison of lactated Ringer's solution and 0.9% NaCl during renal transplantation. Anesth. Analg. 2005 May;100(5):1518-24.</ref>
*The small amount of 4 mEq/L of potassium in lactated ringers does not contribute to worsening hyperkalemia
*Hyperkalemia worsens with metabolic acidosis, and large volume normal saline administration increases risk of hyperchloremic non-anion gap metabolic acidosis


7/2/09 Adapted from Tintinalli, Donaldson, Pani
==Disposition==
*Consideration for ICU for frequent electrolyte checks and close cardiac monitoring


==See Also==
*[[Electrolyte abnormalities]]
*[[Acute kidney injury]]
*[[Hemodialysis/Hemoperfusion]]
*[[Crush syndrome]]


==External Links==
*[https://ecgweekly.com/2015/01/case-of-the-week-january-12-2015/ ECG Weekly -Hyperkalemia]


==References==
<references/>


[[Category:FEN]]
[[Category:FEN]]
[[Category:Renal]]

Latest revision as of 15:08, 8 August 2022

Background

  • Defined as >5.5 mEq/L
  • Potassium secretion is proportional to flow rate and sodium delivery through distal nephron
    • Thus, loop & thiazide diuretics cause hypokalmia
  • Most common cause is hemolysis from blood draw (pseudohyperkalemia)

Medication Causes

Alter transmembrane potassium movement

  • β blockers
  • Digoxin
  • Potassium-containing drugs
  • Potassium supplements
  • Salt substitutes
  • Hyperosmolar solutions (mannitol, glucose)
  • Suxamethonium
  • Intravenous cationic amino acids
  • Stored red blood cells (haemolysis releases potassium)
  • Herbal medicines (such as alfalfa, dandelion, horsetail, milkweed, and nettle)

Reduce aldosterone secretion

Block aldosterone binding to mineralocorticoid receptors

Clinical Features

Typically non-specific

Differential Diagnosis

Hyperkalemia

  • Pseudohyperkalemia: hemolyzed specimen, prolonged tourniquet use prior to blood draw, thrombocytosis or leukocytosis
  • Redistribution (shift from intracellular to extracellular space)
  • Increased total body potassium
    • Inadequate excretion: Acute/chronic renal failure, Addison's disease, type 4 RTA
    • Drug-induced: potassium-sparing diuretic (spironolactone), angiotensin converting enzyme inhibitors (ACE-I), nonsteroidal anti-inflammatory drugs (NSAIDs)
    • Excessive intake: diet, blood transfusion
  • Other causes: succinylcholine, digitalis, beta-blockers

Peaked T-waves

Wide-complex tachycardia

Assume any wide-complex tachycardia is ventricular tachycardia until proven otherwise (it is safer to incorrectly assume a ventricular dysrhythmia than supraventricular tachycardia with abberancy)

^Fixed or rate-related

Evaluation

Diagrammatic representation of ECG changes with increasing hyperkalemia
ECG in hyperkalemia with peaked T waves and small P waves
ECG with widened QRS complex and tall broad T waves
ECG showing sine wave pattern

Workup

  • ECG
  • Chem 10 (including potassium, magnesium, and phosphorus)
    • Consider point-of-care lab testing for more rapid result
  • Consider ABG/VBG to evaluate pH

ECG

Changes NOT always predictable and sequential

  • 6.5 - 7.5 mEq/L: peaked T waves, prolonged PR interval, shortened QT interval
  • 7.5 - 8.0 mEq/L: widened QRS interval, flattened P waves
  • 10 - 12 mEq/L: sine wave, ventricular fibrillation, heart block

Diagnosis

  • Based on lab testing (>5.5 mEq/L), although ECG may provide earlier information
  • Consider pseudohyperkalemia (e.g. from hemolysis)

Management

Stabilize cardiac membranes

Indicated if there are any ECG changes or evidence of arrhythmias. Consider if K >7 mEq/L

  • Either one of the following:
    • Calcium gluconate: Give 10ml of a 10% solution (1 gram) over 5-10 mins. In severe cases may have to start with higher dose of 3 grams (30 mLs) and repeat doses (up to 9-15 grams total).
      • Only 1/3 the elemental calcium compared to calcium chloride.
      • Can cause hypotension due to osmotic shift
    • Calcium chloride 1 gram IV
      • Give over 1 - 2 minutes
      • Extravasation is bad: use a good IV
      • Usually given in code situations
  • Takes effect in 15-30 minutes[1]
    • (If given for hyperkalemic cardiac arrest, need to continue resuscitation for at least 30 minutes)
  • Duration of action: 30 - 60 minutes [2]
  • Use caution in patients taking Digoxin although risk of Stone heart may be unsubstantiated [3]
  • Do serial ECGs to track progress: may need to give multiple doses

Shift K+ intracellularly

  • Intravenous insulin + dextrose
    • Give 10 units regular insulin intravenously with 25 to 50 grams (1 - 2 50 mL ampules) of 50% dextrose (D50)
      • May withhold dextrose if blood sugar >300mg/dl (>17 mmol/L)
      • Duration of effect: 4 - 6 hours
      • Consider mixing in 10 cc NS syringe to ensure small volume of 10 units insulin fully administered via IV
      • Insulin cleared renally, be careful about inducing hypoglycemia (ESRD patients).
        • In a small 2017 retrospective cohort study, researchers found that giving 5 units of insulin instead of 10 units reduced serum potassium to the same extent as 10 units, with a lower rate of hypoglycemia.
        • Consider decreasing to 5 units or increasing dextrose dose to 50g with following risk factors: pretreatment blood glucose <150, acute kidney injury/chronic kidney disease, no history of DM, weight <60kg, female sex [4]
  • Nebulized albuterol 15 - 20mg
    • Response is dose-dependent
    • Peak effect: 30 minutes
    • Duration of effect: 2 hours
  • Sodium bicarbonate
    • Generally not considered unless pH <7.1
    • Pushing "ampules of hypertonic bicarbonate have been proven to be ineffective in RCTs"[5]
    • For normovolemic or hypovolemic patients with metabolic acidosis:
      • Give three amps of bicarbonate in a liter of D5W or sterile water

Remove K+ from body

  • Intravenous furosemide (Lasix) 40 - 80mg
    • Ensure adequate urine output first
    • Decreases the potassium in three ways: dilution, shifting of potassium into muscle cells, and promotion of renal potassium excretion by alkalosis[6]
    • More on how to use Lasix: IBCC Hyperkalemia Chapter
  • Sodium polystyrene sulfonate (Kayexalate): 30 gm oral or per rectum
  • Sodium zirconium cyclosilicate (Lokelma)
    • Potassium binder, similar to Kayexalate but without risk of bowel perforation[7]
    • 10 mg PO TID for up to 48 hours, then 10-15 mg PO QD for maintenance
  • Intravenous lactated ringers solution for volume expansion if dehydrated, rhabdomyolysis, diabetic ketoacidosis or other acidosis (avoid NS, causes hyperchloremic acidosis which shifts potassium out of cells increasing level)
    • consider isotonic bicarbonate if significant acidosis (D5W with 3 amps of bicarb per liter), can calculate bicarbonate deficit then divide by 150mEq/L to estimate number of liters of isotonic bicarbonate required) [8]
  • Hydrocortisone if suspicious for adrenal insufficiency
  • Definitive treatment is hemodialysis

IV Fluid Choice

  • LR is preferred over NS, even in renal failure[9]
  • The small amount of 4 mEq/L of potassium in lactated ringers does not contribute to worsening hyperkalemia
  • Hyperkalemia worsens with metabolic acidosis, and large volume normal saline administration increases risk of hyperchloremic non-anion gap metabolic acidosis

Disposition

  • Consideration for ICU for frequent electrolyte checks and close cardiac monitoring

See Also

External Links

References

  1. ↑ http://lifeinthefastlane.com/hyperkalemia/. Accessed 02/22/2016
  2. ↑ The Effect of Calcium on Severe Hyperkalemia http://hqmeded-ecg.blogspot.com/2015/04/the-effect-of-calcium-on-severe.html
  3. ↑ Erickson CP, Olson KR. Case files of the medical toxicology fellowship of the California poison control system-San Francisco: calcium plus digoxin-more taboo than toxic? J Med Toxicol. 2008 Mar;4(1):33-9
  4. ↑ Moussavi K1, Fitter S2, Gabrielson SW3, Koyfman A4, Long B5. Management of Hyperkalemia With Insulin and Glucose: Pearls for the Emergency Clinician. J Emerg Med. 2019 Jul;57(1):36-42.
  5. ↑ IBCC Hyperkalemia Chapter
  6. ↑ IBCC Hyperkalemia Chapter
  7. ↑ Beccari, Mario V, and Calvin J Meaney. “Clinical utility of patiromer, sodium zirconium cyclosilicate, and sodium polystyrene sulfonate for the treatment of hyperkalemia: an evidence-based review.” Core evidence vol. 12 11-24. 23 Mar. 2017, doi:10.2147/CE.S129555
  8. ↑ https://emcrit.org/pulmcrit/fluid-selection-using-ph-guided-resuscitation
  9. ↑ O'Malley CM, Frumento RJ, Hardy MA, Benvenisty AI, Brentjens TE, Mercer JS, Bennett-Guerrero E. A randomized, double-blind comparison of lactated Ringer's solution and 0.9% NaCl during renal transplantation. Anesth. Analg. 2005 May;100(5):1518-24.
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