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


High = >5.5meq/L
===Medication Causes===
High! = >6.5meq/L
====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)


==Diagnosis==
====Reduce aldosterone secretion====
*[[ACE inhibitors]]; [[Angiotensin II receptor blockers]]
*[[NSAIDs]]
*[[Heparin]]
*[[Antifungals]] ([[ketoconazole]], [[fluconazole]], [[itraconazole]])
*[[Cyclosporine]]
*[[Tacrolimus]]


Always consider pseudohyperkalemia (e.g. from hemolysis)
====Block aldosterone binding to mineralocorticoid receptors====
*[[Spironolactone]]
*[[Eplerenone]]
*[[Drospirenone]]
*Potassium sparing [[diuretics]] (amiloride, triamterene)
*[[Trimethoprim]]
*[[Pentamidine]]


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


==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. Metabolic Acidosis (drives potassium out of the cells (e.g. DKA))
*6.5 - 7.5 mEq/L: peaked T waves, prolonged PR interval, shortened QT interval
* 2. Cellular breakdown
*7.5 - 8.0 mEq/L: widened QRS interval, flattened P waves
** a. Rhabdomyolysis
*10 - 12 mEq/L: sine wave, ventricular fibrillation, heart block
** 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. Sux, dig, B-blockers
 
==Treatment==


* 1. Calcium Gluconate 1 amp IV
===Diagnosis===
** a. Give only if ECG changes/hypotension/or >7
*Based on lab testing (>5.5 mEq/L), although ECG may provide earlier information
** b. Can give multiple times
*Consider pseudohyperkalemia (e.g. from hemolysis)
** c. Can also give CaCl 1 amp (but can lead to calcium toxicity)
** d. Caution in dig-toxic patients!
** e. Effect begins within minutes, lasts 30-60 minutes


* 2. Albuterol neb 10mg in 4mL saline over 10 min
==Management==
** a. Peak effect within 90 min
===Stabilize cardiac membranes===
** b. Lowers K ~ 0.5-1.5
''Indicated if there are any ECG changes or evidence of arrhythmias. Consider if K >7 mEq/L''
* 3. Reg insulin 10 U IV with 1 amp D50W IV now, and 1 amp in 15 min
*Either one of the following:
** a. Effect begins in 10-20 min, peaks at 30-60 min, lasts 4-6 hours
**[[Calcium gluconate]]: Give 10ml of a 10% solution over 10 mins
** b. Lowers K ~ 0.5 - 1.2
***Only 1/3 the calcium compared to calcium chloride
* 4. Bicarbonate
***Can cause hypotension due to osmotic shift
** a. Controversial
**[[Calcium chloride]] 1 gram IV  
** b. NaBicarb 1 amp IV (over 5 min)
***Give over 1 - 2 minutes
* 5. Kayexalate 30g PO or 50g PR (may cause hypernatremia and volume overload)
***Extravasation is bad: use a good IV
* 6. Dialyisis
***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


===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 [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]]
**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>
*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]]

Revision as of 18:04, 1 July 2020

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

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 over 10 mins
      • Only 1/3 the 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
    • Potassium binder, similar to Kayexalate but without risk of bowel perforation[7]
  • 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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