Hyperkalemia – EMCrit Venture

Hyperkalemia - EMCrit Project
September 23, 2020 0 Comments

CONTENTS


Analysis of hyperkalemia

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scientific shows
  • Left untreated, hyperkalemia might manifest within the following methods:
    • Neuromuscular weak spot (uncommonly seen).
    • Bradycardia
    • Ventricular tachycardia/fibrillation, sudden cardiac loss of life.
  • In follow, most sufferers are asymptomatic (even with extreme hyperkalemia).
EKG analysis
  • Hyperkalemia could cause a really big selection of EKG modifications.
    • The textbook sequence of modifications illustrated above usually would not happen.1  As an alternative, hyperkalemia can mimic all kinds of pathologies (together with STEMI and all forms of bundle/conduction blocks).
    • Extreme hyperkalemia (e.g. Okay>7 mM) can happen with out apparent EKG modifications.
  • The next patterns are extremely suggestive of hyperkalemia.  In an unstable affected person, it might be cheap to present IV calcium primarily based on patterns #2-4 under whereas awaiting a potassium degree.
  • (1) Peaked T-waves
    • Slim, pointy, outstanding T-waves.
    • Usually probably the most notable discovering on the EKG (could also be seen on bedside monitor as nicely).
  • (2) Ventricular tachycardia mimic
    • QRS wave widens and P-waves might disappear.  If affected person is tachycardic, this may seem like ventricular tachycardia.
    • Helpful clues:  In comparison with ventricular tachycardia, T-waves might be sharper than could be typical and coronary heart charge is usually slower than could be typical.
  • (3) Sine-wave sample
    • Profound widening of QRS complicated and peaked T-waves mimics a sine wave.
  • (4) Bradycardia
    • Hyperkalemia can manifest with bradycardia (usually within the context of different medication that decelerate the AV node).
    • There ought to at all times be a excessive suspicion for hyperkalemia in any bradycardic affected person, particularly if there are different EKG findings to counsel hyperkalemia.
lab analysis
  • Hyperkalemia is variably outlined as potassium >5.5 mM or >5.0 mM, relying on the supply.
  • Pseudohyperkalemia refers to artificially elevated potassium on account of:
    • (a) Hemolysis
    • (b) Extreme polycythemias inflicting potassium launch throughout clotting (e.g., platelets > 1 million or WBC depend > 50,000).  This may be averted by point-of-care testing or measuring labs in a heparinized tube.
    • (c) Extended tourniquet software.
  • The primary response to a lab report of hyperkalemia must be to take a look at the telemetry tracing and procure an EKG.
    • If the telemetry/EKG exhibits options of hyperkalemia, this confirms the analysis.
    • If the lab experiences extreme hyperkalemia however the EKG is regular, repeat the lab.


Causes of hyperkalemia

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common ideas
  • Usually the kidney will stop hyperkalemia by growing urinary potassium excretion.  Persistent hyperkalemia implies dysfunction in renal potassium excretion.
  • Critically ailing sufferers usually develop hyperkalemia on account of a mix of a number of elements (e.g. hypovolemia plus renal dysfunction plus ACE-inhibitor).  Profitable remedy might require addressing many of those issues concurrently.
differential analysis
  • Pseudohyperkalemia
    • Hemolysis
    • Extreme leukocytosis/thrombocytosis
    • Delayed pattern processing
  •  Iatrogenic
    • Potassium dietary supplements
    • ACEi / ARB, aliskiren (renin-inhibitor)
    • NSAIDs
    • Beta-blockers (principally nonselective brokers, e.g. labetalol)
    • Potassium-sparing diuretics (amiloride, triamterene, spironolactone, eplerenone)
    • Antibiotics (trimethoprim, pentamidine, ketoconazole, IV penicillin2)
    • Heparin
    • PRBC transfusion
    • Cyclosporine, tacrolimus
    • Digoxin toxicity, succinylcholine
  • Diabetic ketoacidosis, hyperglycemic hyperosmolar non-ketotic syndrome (HHNS)
  • Mobile lysis
    • Hemolysis, hematoma
    • Rhabdomyolysis
    • Tumor lysis syndrome
    • Tissue necrosis of different etiologies (e.g. trauma, infarction)
  • Renal failure, primarily if there may be:
  • Dysfunction of the renin-angiotensin-aldosterone system (Sort IV renal tubular acidosis):
investigation
  • Evaluate remedy record and contemplate scientific context.
  • Think about analysis for mobile lysis (e.g. measure CK & LDH ranges).
  • Think about analysis for adrenal insufficiency (e.g. random cortisol, ACTH stimulation check).3


Danger stratification

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Step one of remedy requires figuring out whether or not hyperkalemia is life-threatening (extreme).  No evidence-based definition for “extreme” hyperkalemia exists (numerous articles use a variety of semi-arbitrary definitions).  In the end scientific judgement is required, with consideration to the next elements:

  • Potassium degree:  above 6.5-7 mM is extra worrisome.
  • Chronicity:
    • Persistent hyperkalemia is healthier tolerated (e.g. dialysis sufferers who regularly have hyperkalemia).
    • Acute hyperkalemia is extra harmful.
  • EKG modifications:  bradycardia, QRS widening, or junctional rhythm are notably worrisome.4
  • Ongoing potassium launch (e.g. by tumor lysis syndrome or rhabdomyolysis) will increase the probability of degradation.


Remedy of reasonable hyperkalemia

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step 1:  deal with any definable causes
  • Deal with all identifiable causes of hyperkalemia.
  • Discontinue any nephrotoxins and set up a state of euvolemia with satisfactory perfusion.
  • Think about a renal eating regimen with restricted potassium consumption.
step 2:  mild kaliuresis (renal excretion of potassium)
  • Potassium excretion can typically be promoted utilizing diuretic amongst sufferers in a position to produce urine (in any other case dialysis will probably be wanted).
  • Average hyperkalemia can typically be handled with a single diuretic (e.g. IV furosemide), adopted by quantity alternative with Lactated Ringer’s to keep up a web even fluid stability.
  • If this routine fails, extra aggressive kaliuresis could also be utilized with further medicines mentioned under.


Rx extreme hyperkalemia: Temporizing measures

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IV calcium to stabilize the myocardium
  • Preliminary dose:
    • Peripheral entry:  3 grams IV calcium gluconate over 10 minutes.
    • Central entry: 1 gram IV calcium chloride over 10 minutes or sluggish IV push.
  • Additional doses of calcium could also be indicated for persistent, harmful arrhythmias (e.g. ongoing bradycardia with hypoperfusion).
    • Ideally suited dosing right here is unknown.  An professional guideline really useful re-dosing a couple of times if wanted, whereas admitting the shortage of proof.5
    • Normally hyperkalemia is extra harmful than hypercalcemia, so that you’re in all probability higher off erring on the facet of hypercalcemia.  In case you have a point-of-care electrolyte monitor obtainable, verify calcium ranges and keep away from pushing the ionized calcium >3 mM.
  • Calcium solely lasts 30-60 minutes, so it might must be repeated.
IV insulin to shift potassium into cells
  • Dose:
    • 5 models IV insulin (should be given IV).(28976587)
    • 2 ampules of D50W (100 ml whole), though this can be omitted if the glucose is already >250 mg/dL.6
  • Lasts for a number of hours, might must be re-dosed.
  • Observe glucose rigorously (e.g. q1hr) to keep away from hypoglycemia, particularly in sufferers with renal dysfunction, in whom insulin might linger.
beta-2 agonists
  • Albuterol
    • Causes a small shift of potassium into cells.
    • Requires a lot of albuterol (10-20 mg, equal to about 4-8 nebulized therapies back-to-back).  Logistically, one of the best ways to attain this dose is to supply albuterol as a steady nebulized remedy.
  • IV epinephrine
    • Ought to not be used solely for hyperkalemia.  Nevertheless, if the affected person does require a vasopressor, then epinephrine could also be a good selection.
    • Epinephrine is phenomenal for hyperkalemia-induced bradycardia, as a result of it concurrently treats each the hyperkalemia and the bradycardia.
bicarbonate
  • Hypertonic bicarbonate would not work.
    • Ampules of hypertonic bicarbonate have been confirmed to be ineffective in RCTs.7 8 9 10
    • The hypertonic nature of the fluid pulls potassium out of the cells on account of osmotic shifts (“solvent drag”).11  This counteracts the impact of accelerating the pH, with an general impartial impact on the potassium.
  • Isotonic bicarbonate does work in metabolic acidosis.
    • Isotonic bicarbonate is usually obtained by including three amps of bicarbonate to a liter of D5W (this creates a 150 mM answer of bicarbonate).
    • Isotonic bicarbonate decreases the potassium in 3 ways: (1) dilution, (2) shifting of potassium into muscle cells, (3) renal potassium excretion is promoted by alkalosis.12
    • This has been demonstrated to work, however solely for sufferers with metabolic acidosis.8 13 14  Sadly, this requires giving 1-2 liters of fluid, a quantity which many sufferers will probably be unable to tolerate.
    • Dosing is mentioned within the part under on quantity resuscitation.


Rx extreme hyperkalemia: Potassium elimination

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dialysis vs. kaliuresis
  • In the end, most sufferers would require elimination of extra potassium from the physique.  This can be achieved both by way of the kidneys (kaliuresis) or by way of dialysis.
    • Neither kayexalate nor patiromer has been confirmed to decrease potassium acutely.15 16  Neither one at present has a task for emergent remedy of hyperkalemia.
  • Sufferers with end-stage renal illness on power dialysis would require emergent dialysis (there is no such thing as a level in making an attempt kaliuresis).  For many different sufferers, kaliuresis must be tried previous to emergent dialysis.
kaliuresis step #1 = quantity resuscitation if hypovolemic
  • Many sufferers current with renal failure and hyperkalemia on account of quantity depletion.   Step one in managing these sufferers is quantity repletion.
  • Isotonic bicarbonate is the popular resuscitative fluid in metabolic acidosis (excluding lactic acidosis or ketoacidosis).
    • The isotonic bicarbonate must be dosed with the objective of bringing the affected person’s serum bicarbonate degree again to a high-normal degree (e.g. bicarbonate 24-28 mM).  The dose might be estimated by calculating the affected person’s bicarbonate deficit (MDCalc).  Divide the bicarbonate deficit by 150 to estimate the variety of liters of isotonic bicarbonate wanted.  The dose is often 1-2 liters.
    • Bicarbonate must be infused quickly for sufferers with hypovolemia and extreme hyperkalemia (e.g. 500-1,000 ml/hour).
    • If the affected person stays hypovolemic after receiving sufficient sodium bicarbonate to normalize the serum bicarbonate degree, then residual hypovolemia might be handled with lactated ringers.
  • Within the absence of metabolic acidosis, lactated ringers is most popular because the resuscitative fluid (whereas regular saline is contraindicated).
    • The normal dogma that lactated ringers is contraindicated in hyperkalemia is unsuitable.  The truth is, regular saline tends to trigger an acidosis which exacerbates hyperkalemia.17 18 19 20
    • Plasmalyte or normosol are additionally effective decisions right here.
kaliuresis step #2 = contemplate fludrocortisone
  • Oral fludrocortisone (0.2 mg each day) might assist stimulate the kidneys to secrete potassium.
  • That is primarily helpful in sufferers with mineralocorticoid insufficiency (inexperienced containers above, for instance sufferers on ACEi/ARB or NSAIDs).
kaliuresis step #3 = diuretic cocktail
  • The spine of kaliuresis is a mix of potassium-wasting diuretics, which synergize to trigger potassium excretion within the urine.
    • Diuretic dose must be adjusted primarily based on the severity of the hyperkalemia and the diploma of the renal dysfunction (renal dysfunction typically causes diuretic resistance).
    • In emergent hyperkalemia, it is higher to err on the facet of giving extreme diuretic.  If the affected person experiences a large-volume diuresis, this may be simply corrected by giving again IV fluid.  Alternatively, if in insufficient diuretic dose is given, this may occasionally trigger the affected person to be dialyzed unnecessarily.
  • For optimum efficacy a mix of three diuretics could also be used (when given at maximal doses that is termed the nephron bomb).
    • 1) Loop diuretic:  furosemide 80-160 mg IV or bumetanide 2-4 mg IV
    • 2) Thiazide diuretic:  chlorothiazide 500-1000 mg IV
    • 3)  Acetazolamide 500-1,000 mg IV
kaliuresis step #4 = decide response to diuretic
  • If the affected person would not produce urine in response to diuretic, dialysis will typically be required.
  • If the affected person does produce urine:
    • Urine quantity ought to typically get replaced with Lactated Ringers to forestall quantity depletion.
    • Electrolytes (together with magnesium) must be checked regularly and repleted as wanted.


algorithm

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questions & dialogue

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To maintain this web page small and quick, questions & dialogue about this publish might be discovered on one other web page right here.

  • The next therapies must be averted: kayexalate, hypertonic bicarbonate (bicarbonate ampules), regular saline.
  • Do not present temporizing measures with out definitive remedy (e.g. affected person is given insulin/glucose however no different remedy).  This may briefly make the potassium look higher, however the hyperkalemia will inevitably recur afterward.
  • Insulin dosing errors: 10 models should be given intravenously (not subcutaneously).
Video summarizing remedy of hyperkalemia (Christopher Nemeh)

Going additional: 
  • Basic
  • EKG in hyperkalemia
  •  Kayexalate

References

1.

Palmer B, Clegg D. Analysis and remedy of hyperkalemia. Cleve Clin J Med. 2017;84(12):934-942. [PubMed]

2.

Penicillin is available in a wide range of completely different varieties.  Intravenous penicillin G-potassium comprises potassium.

3.

For conditions the place there is no such thing as a clear reason for hyperkalemia, additional investigation might contain measurement of renin and aldosterone ranges.  These take without end to return and often aren’t useful within the acute administration part.  .

4.

Durfey N, Lehnhof B, Bergeson A, et al. Extreme Hyperkalemia: Can the Electrocardiogram Danger Stratify for Quick-term Hostile Occasions? West J Emerg Med. 2017;18(5):963-971. [PubMed]

5.

Rossignol P, Legrand M, Kosiborod M, et al. Emergency administration of extreme hyperkalemia: Guideline for greatest follow and alternatives for the long run. Pharmacol Res. 2016;113(Pt A):585-591. [PubMed]

6.

Harel Z, Kamel Okay. Optimum Dose and Methodology of Administration of Intravenous Insulin within the Administration of Emergency Hyperkalemia: A Systematic Evaluate. PLoS One. 2016;11(5):e0154963. [PubMed]

7.

Blumberg A, Weidmann P, Shaw S, Gnädinger M. Impact of varied therapeutic approaches on plasma potassium and main regulating elements in terminal renal failure. Am J Med. 1988;85(4):507-512. [PubMed]

8.

Blumberg A, Weidmann P, Ferrari P. Impact of extended bicarbonate administration on plasma potassium in terminal renal failure. Kidney Int. 1992;41(2):369-374. [PubMed]

9.

Kim H. Mixed impact of bicarbonate and insulin with glucose in acute remedy of hyperkalemia in end-stage renal illness sufferers. Nephron. 1996;72(3):476-482. [PubMed]

10.

Kim H. Acute remedy for hyperkalemia with the mixed routine of bicarbonate and beta(2)-adrenergic agonist (salbutamol) in power renal failure sufferers. J Korean Med Sci. 1997;12(2):111-116. [PubMed]

11.

Conte G, Dal C, Imperatore P, et al. Acute improve in plasma osmolality as a reason for hyperkalemia in sufferers with renal failure. Kidney Int. 1990;38(2):301-307. [PubMed]

12.

Weisberg L. Administration of extreme hyperkalemia. Crit Care Med. 2008;36(12):3246-3251. [PubMed]

13.

Fraley D, Adler S. Correction of hyperkalemia by bicarbonate regardless of fixed blood pH. Kidney Int. 1977;12(5):354-360. [PubMed]

14.

Gutierrez R, Schlessinger F, Oster J, Rietberg B, Perez G. Impact of hypertonic versus isotonic sodium bicarbonate on plasma potassium focus in sufferers with end-stage renal illness. Miner Electrolyte Metab. 1991;17(5):297-302. [PubMed]

15.

Lengthy B, Warix J, Koyfman A. Controversies in Administration of Hyperkalemia. J Emerg Med. 2018;55(2):192-205. [PubMed]

16.

Sterns R, Rojas M, Bernstein P, Chennupati S. Ion-exchange resins for the remedy of hyperkalemia: are they secure and efficient? J Am Soc Nephrol. 2010;21(5):733-735. [PubMed]

17.

O’Malley C, Frumento R, Hardy M, et al. A randomized, double-blind comparability of lactated Ringer’s answer and 0.9% NaCl throughout renal transplantation. Anesth Analg. 2005;100(5):1518-24, desk of contents. [PubMed]

18.

Khajavi M, Etezadi F, Moharari R, et al. Results of regular saline vs. lactated ringer’s throughout renal transplantation. Ren Fail. 2008;30(5):535-539. [PubMed]

19.

Modi M, Vora Okay, Parikh G, Shah V. A comparative research of impression of infusion of Ringer’s Lactate answer versus regular saline on acid-base stability and serum electrolytes throughout reside associated renal transplantation. Saudi J Kidney Dis Transpl. 2012;23(1):135-137. [PubMed]

20.

Weinberg L, Harris L, Bellomo R, et al. Results of intraoperative and early postoperative regular saline or Plasma-Lyte 148® on hyperkalaemia in deceased donor renal transplantation: a double-blind randomized trial. Br J Anaesth. 2017;119(4):606-615. [PubMed]

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