Table of Contents

 

1. Abstract
2. Case Presentations
3. Introduction
4. Critical Appraisal of the Literature
5. Pathophysiology Of Potassium Regulation
6. Etiologies Of Hypokalemia
   1. Inadequate Intake
   2. Renal Loss
   3. Gastrointestinal Loss
   4. Sweat Loss
7. Etiologies Of Hyperkalemia
   1. Pseudohyperkalemia
   2. Impaired Excretion Of Potassium
   3. Medication-Induced Hyperkalemia
      1. Potassium-Containing Agents
      2. Medications That Affect Aldosterone Secretion
      3. Medications That Cause Tubular Resistance To The Action Of Aldosterone
      4. Medications That Cause Transmembrane Shifting Of Potassium
8. Differential Diagnosis
9. Prehospital Care
10. Emergency Department Evaluation
    1. History
    2. Physical Examination
11. Diagnostic Studies
    1. Electrocardiogram Findings In Hypokalemia
    2. Electrocardiogram Findings In Hyperkalemia
12. Treatment Of Hypokalemia
13. Treatment Of Hyperkalemia
    1. Membrane Stabilization
    2. Transcellular Shift
    3. Removal Of Potassium
       1. Cation Exchange Resins
       2. Dialysis
14. Special Considerations
    1. Rapid Sequence Intubation
    2. Genetic Disorders
    3. Myocardial Infarction
    4. Digoxin Toxicity
    5. Periodic Paralysis
       1. Hypokalemic Periodic Paralysis
       2. Hyperkalemic Periodic Paralysis
       3. Andersen Syndrome
15. Controversies And Cutting Edge
16. Disposition
17. Summary
18. Risk Management Pitfalls For Potassium Emergencies In The Emergency Department
19. Time- And Cost-Effective Strategies
20. Case Conclusions
21. Clinical Pathways
    1. Clinical Pathway For Management Of Hypokalemia In The Emergency Department
    2. Clinical Pathway For Management Of Hyperkalemia In The Emergency Department
22. Tables and Figures
    1. Table 1. Severity Classifications Of Hypokalemia And Hyperkalemia
    2. Table 2. Common Causes Of Hypokalemia
    3. Table 3. Proper Phlebotomy Techniques To Reduce Pseudohyperkalemia
    4. Table 4. Medications That Can Cause Hyperkalemia
    5. Table 5. Typical Causes Of Hypokalemia In Conjunction With Laboratory Testing
    6. Table 6. Interventions Used In The Treatment Of Hyperkalemia
    7. Figure 1. Electrocardiogram With Peaked T Waves And PR Depression In Hyperkalemia
    8. Figure 2. Electrocardiogram With A Widened QRS In Hyperkalemia
    9. Figure 3. Electrocardiogram In Hyperkalemia Depicting A Sine Wave
23. References

Abstract

Hypokalemia and hyperkalemia are the most common electrolyte disorders managed in the emergency department. The diagnosis of these potentially life-threatening disorders is challenging due to the often vague symptomatology a patient may express, and treatment options may be based upon very little data due to the time it may take for laboratory values to return. This review examines the most current evidence with regard to the pathophysiology, diagnosis, and management of potassium disorders. In this review, classic paradigms, such as the use of sodium polystyrene and the routine measurement of serum magnesium, are tested, and an algorithm for the treatment of potassium disorders is discussed.

Case Presentations

An elderly woman presents with 4 days of generalized weakness and fatigue secondary to diarrhea. On examination, she appears dehydrated. During your workup, you find that she is in acute renal failure and is suffering from hyperkalemia, with a serum potassium of 6.5 mEq/L. Her ECG shows mild peaked T waves. During discussion with the admitting physician, you are asked to give the patient sodium polystyrene. You seem to recall some controversy regarding this treatment and wonder if it is really indicated for this patient.

Your next patient is a 24-year-old woman with diarrhea and vomiting. During your workup, you find that she has hypokalemia, with a potassium level of 2.2 mEq/L, an ECG with a prolonged QT interval, and a serum magnesium of 1.9 mEq/L. The patient’s internist recommends treatment with an antiemetic, oral potassium, and discharge home. You wonder if this is the best management plan.

Your third patient is a dialysis-dependent 56-year-old man who presents with shortness of breath and weakness. His serum potassium is 6.9 mEq/L, and there is evidence of fluid overload on the chest radiograph. You contact renal to arrange emergent dialysis and they recommend that you administer a “new” potassium-binding agent and discharge the patient for his regularly scheduled dialysis appointment later in the day. You wonder what these new agents are and whether best practice has recently changed without your being aware of it.

Introduction

Potassium disorders are common and potentially deadly, which makes early recognition and treatment fundamental to quality emergency care. The symptoms that a patient may experience with these disorders are typically vague and difficult to distinguish. The emergency clinician must have a heightened index of suspicion and a low threshold for testing and treating. Recent literature has questioned several age-old practices and has challenged the emergency clinician to assess new practice paradigms, including the routine ordering of serum magnesium levels in patients with hypokalemia, redrawing potassium levels in a hemolyzed sample, proper blood-drawing techniques, and the utility of sodium polystyrene sulfonate and bicarbonate in the treatment of acute hyperkalemia. This issue of Emergency Medicine Practice provides a systematic review of the newest evidence regarding the pathophysiology, diagnosis, and management of potassium-related emergencies.

Critical Appraisal Of The Literature

A MEDLINE^® search for randomized controlled trials since 2010 was conducted using the search terms hyperkalemia and hypokalemia. MEDLINE^® was also queried using the terms hyperkalemia and hypokalemia and therapy or treatment in order to identify studies that have not yet reached the randomized controlled trial phase. A total of 281 articles were identified and reviewed, with 118 being for hyperkalemia and 163 articles for hypokalemia. The literature reviewed had numerous large retrospective studies but very few randomized controlled trials for either hyperkalemia or hypokalemia. Moreover, very few articles reviewed dealt with new management strategies of these disease processes. The National Guideline Clearinghouse (www.guideline.gov) was searched and no recommendations for the treatment of hyper-kalemia or hypokalemia were found. The Cochrane Database of Systematic Reviews was also queried. No reviews have been published for hypokalemia; a review was published in 2009 for hyperkalemia, but it has not been updated.

Risk Management Pitfalls For Potassium Emergencies In The Emergency Department

1. “Sure, the patient had hypokalemia, and I was treating it with intravenous potassium, but I didn’t think she needed a monitor.”
   All patients receiving potassium via the intravenous route should be on a cardiac monitor both during and after infusion to assess for dysrhythmias.
    
2. “That end-stage renal disease patient is always here with moderate hyperkalemia. I gave him a dose of sodium polystyrene sulfate and sent him to dialysis.”
   Emergent dialysis is the treatment of choice for patients who are dialysis-dependent with hyperkalemia. The binding resins have not been proven to rapidly lower potassium levels in the acute setting.
    
3. “Although the patient’s potassium was 7.1 mEq/L, she had a normal ECG.”
   The ECG is unreliable in predicting which patients with hyperkalemia will rapidly decompensate and it should not be the sole factor in initiating treatment.
    
4. “The laboratory results were clearly due to hemolysis, so I didn’t treat the hyperkalemia.”
   Although new data have shown that not all laboratory tests need to be redrawn, particularly in patients with normal renal function and a normal ECG, the clinical picture should guide care. If you suspect renal failure with associated hyperkalemia, then the patient should be treated appropriately and tests redrawn.
    
5. “The patient’s potassium was the low end of normal after his myocardial infarction, and his cardiac arrest was most likely secondary to his underlying heart condition.”
   Hypokalemia has been associated with ventricular fibrillation in myocardial infarction patients and a serum potassium of at least 4.5 mEq/L should be maintained.
    
6. “The patient had moderate hyperkalemia with ECG changes. I gave a dose of calcium and admitted him to the internist. I can’t believe he coded when he got to the floor.”
   Calcium is a membrane stabilizer and is cardioprotective for patients with hyperkalemia. However, it does not lower the total serum potassium, and other interventions must be employed.
    
7. “Sure, the child had some fatigue, but he looked well. I sent him back to his pediatrician for a further workup.”
   Genetic renal disorders of childhood can present with vague complaints and warrant testing in the ED, if suspected.
    
8. “The patient’s potassium was 2.4 mEq/L, but she was asymptomatic. I sent her home with a prescription for oral potassium replacement and a repeat basic metabolic panel in a week.”
   Severe hypokalemia warrants intravenous potassium replacement and admission for further stabilization, due to the risk of arrhythmia.
    
9. “I treated the patient’s hyperkalemia with insulin and dextrose and sent him to the floor. I am not sure why he was unresponsive when he got there.”
   Patients treated with insulin and dextrose for hyperkalemia should be placed on a glucose monitoring protocol for several hours.
    
10. “I gave the patient one of the new potassium-binding resins for her hyperkalemia and sent her home for follow-up with her primary care physician.”
    Both sodium zirconium cyclosilicate and patiromer have not been studied in the acute management of hyperkalemia. The only proven acute management strategy for potassium removal is dialysis.

Tables And Figures

References

Evidence-based medicine requires a critical appraisal of the literature based upon study methodology and number of subjects. Not all references are equally robust. The findings of a large, prospective, randomized, and blinded trial should carry more weight than a case report.

To help the reader judge the strength of each reference, pertinent information about the study is included in bold type following the reference, where available.

1. Huang CL and Kuo E. Mechanism of hypokalemia in magnesium deficiency. J Am Soc Nephrol. 2007;2649-2652.
2. Brophy DF. Disorders of potassium and magnesium homeostasis. In: DiPiro JT, Talbert RL, Yee GC, et al, editors. Pharmacotherapy: A Pathophysiologic Approach. 9th ed. New York, New York: McGraw-Hill; 2014. (Book chapter)
3. Eliacik E, Yildrim T, Sahin U, et al. Potassium abnormalities in current clinical practice: frequency, causes, severity and management. Med Princ Pract. 2015;24(3):271-275. (Retrospective study; 9045 patients)
4. Crop MJ, Hoorn EJ, Lindermnas J, et al. Hypokalemia and subsequent hyperkalaemia in hospitalized patients. Nephrol Dial Transplant. 2007;22(12):3471-3477. (Retrospective study, 1178 patients)
5. Paice BJ, Paterson KR, Onyanga-Omara F, et al. Record linkage study of hypokalemia in hospitalized patients. Postgrad Med J. 1986; 62(725):187-191. (Retrospective study; 58,167 patients)
6. Jensen HK, Brabrand M, Vinholt PJ, et al. Hypokalemia in acute medical patients: risk factors and prognosis. Am J Med. 2015;128(1):60-67. (Observational cohort study; 11,988 patients)
7. Squires RD, Huth EJ. Experimental potassium depletion in normal human subjects: relation of ionic intakes to the renal conservation of potassium. J Clin Invest. 1959;38(7):1134-1148. (Prospective study; 11 patients)
8. Alderman MH, Piller BL, Ford CE, et al. Clinical significance of incident hypokalemia and hyperkalemia in treated hypertensive patients in the antihypertensive and lipid-lowering treatment to prevent heart attack trial. Hypertension. 2012;59(5):926-933. (Prospective study; 33,357 patients)
9. Brunner FP, Frick PG. Hypokalemia, metabolic alkalosis and hypernatremia due to “massive” sodium penicillin therapy. Brit Med J. 1968;4(5630):550-552. (Case control study; 6 patients)
10. Panichpisal K, Pernett FA, Selhia S, et al. Gitelman-like syndrome after cisplatin theraphy: a case report and literature review. BMC Nephrol. 2006;7:10. (Case study/review)
11. Sato K , Feibleman C, Dobson RL. The electrolyte composition of pharmacologically and thermally stimulated sweat: a comparative study. J Invest Dermatol. 1970;55(6):433-438. (Prospective study; 15 patients)
12. Einhorn LM, Zhan M, Hsu VD et al. The frequency of hyperkalemia and its significance in chronic kidney disease. Arch Intern Med. 2009;169(12):1156-1162. (Retrospective study; 245,808 patients)
13. Drawz PE, Babineau DC, Rahman M. Metabolic complications in elderly adults with chronic kidney disease. J Am Geriatr Soc. 2012;7(8):310-315. (Retrospective study; 13,874 patients)
14. Hayes J, Kalantar-Zadeh K, Lu JL, et al. Association of hypo-and hyperkalemia with disease progression and mortality in males with chronic kidney: the role of race. Nephron Clin Pract. 2012;120(1):c8-c16. (Prospective study; 1227 patients)
15. Sarafidis PA, Blacklock R, Wood E, et al. Prevalence and factors associated with hyperkalemia in predialysis patients followed in a low clearance clinic. Clin J Am Soc Nephrol. 2012;7(8):1234-1241. (Prospective study; 238 patients)
16. Einhorn LM, Zhan M, Hsu VD, et al. The frequency of hyperkalemia and its significance in chronic kidney disease. Arch Intern Med. 2009;169(12):1156-1162. (Retrospective study; 245,808 patients)
17. Forsman RW. Why is laboratory an afterthought for managed care organizations? Clin Chem. 1996;42(5):813-816. (Review)
18. Seimiay M, Yoshida T, Sawabe Y, et al. Reducing the incidence of pseudohyperkalemia by avoiding making a fist during phlebotomy: a quality improvement report. Am J Kidney Dis. 2010;56(4):686-692. (Quality improvement study; 244,992 patients)
19. Loh T, Sethi S. A multidisciplinary approach to reducing spurious hyperkalemia in hospital outpatient clinics. J Clin Nurs. 2015;24(19-20):2900-2906. (Quality improvement study)
20. Kitamura K, Tomita K. Familial psuedohyperkalemia: a rare syndrome, but diverse genetic heterogeneity. Intern Med. 2005;44(8):781-782. (Case series; 6 patients)
21. Khodorkovsky B, Cambria B, Lesser M, et al. Do hemolyzed potassium specimens need to be repeated? J Emerg Med. 2014;47(3):313-317. (Prospective study; 45 patients)
22. Gurwitz JH, Field TS, Harrold LR, et al. Incidence and preventability of adverse drug events among older persons in the ambulatory setting. JAMA. 2003;289(9):1107-1116. (Retrospective study; 27,617 patients)
23. Perazella M. Drug-induced hyperkalemia: old culprits and new offenders. Am J Med. 2000;109(4):307-314. (Review)
24. Raza S, Baig MA, Chang C, et al. A prospective study on red blood cell transfusion related hyperkalemia in the critically ill. J Clin Med Res. 2015;7(6):417-421. (Prospective study; 125 patients)
25. Thiele A, Rehman HU. Hyperkalemia caused by penicillin. Am J of Med. 2008;121(8):e1-e2. (Case study; 1 patient)
26. Mercer CW, Logic JR. Cardiac arrest due to hyperkalemia following intravenous potassium administration. Chest. 1973;64(3):358-359. (Case study; 1 patient)
27. Raebel MA. Hyperkalemia associated with the use of angiotensin converting enzyme inhibitors and angiotensin receptor blockers. Cardvasc Ther. 2012;30(3):e156-e166. (Review)
28. Zimran A, Kramer M, Plaskin M, et al. Incidence of hyperkalemia induced by indomethacin in a hospital population. Br Med J (Clin Res Ed). 1985;291(6488):107-108. (Prospective study; 50 patients)
29. Aljadhey H, Tu W, Hansen RA, et al. Risk of hyperkalemia associated with selective COX-2 inhibitors. Pharmacoepidemiol Drug Saf. 2010;19(11):1194-1198. (Retrospective study; 404 patients)
30. Lafrance JP, Miller DR. Dispensed selective and nonselective nonsteroidal anti-inflammatory drugs and the risk of moderate to severe hyperkalemia: a nested case control study. Am J Kid Dis. 2012;60(1):82-89. (Case-control study; 18,326 patients)
31. Nguyen AT, Gentry CA, Furrh RZ. A comparison of adverse drug reactions between high and standard dose trimethoprim-sulfamethoxazole in the ambulatory setting. Curr Drug Saf. 2013;8(2):114-119. (Retrospective study; 982 patients)
32. Gentry CA, Nguyen AT. An evaluation of hyperkalemia and serum creatinine elevation associated with different dosage levels of outpatient trimethoprim-sulfamethoxazole with or without concomitant medications. Ann Pharmacother. 2013;47(12):1618-1626. (Retrospective study; 6162 patients)
33. Antoniou T, Hollands S, MacDonald EM, et al. Trimethoprim-sulfamethoxazole and risk of sudden death in patients taking spironolactone. CMAJ. 2015;187(4):E138-E143. (Case-control study; 11,968 patients)
34. Antoniou T, Gomes T, Mamdani M, et al. Trimethoprim-sulfamethoxazole induced hyperkalemia in elderly patients receiving spironolactone: nested case control study. BMJ. 2011;343:d5228. (Case-control study; 6903 patients)
35. Marti G, Schwarz C, Leichtle AB, et al. Etiology and symptoms of severe hypokalemia in emergency department patients. Eur J Emerg Med. 2014;21(1):46-51. (Retrospective study; 43,805 patients)
36. Lin SH, Lin YF, Chen DT, et al. Laboratory tests to determine the cause of hypokalemia and paralysis. JAMA Intern Med. 2004;164(14):1561-1566. (Prospective study; 43 patients)
37. Tsuji H, Venditti FJ, Evans JC, et al. The association of levels of serum potassium and magnesium with ventricular premature complexes (the Framingham Heart study). Am J Cardiol. 1994;74(3):232-235. (Retrospective study; 3327 patients)
38. Mattson N, Sadjadieh G, Kumarathurai P, et al. Ambulatory cardiac arrhythmias in relation to mild hypokalaemia and prognosis in community dwelling middle aged and elderly subjects. Europace. 2016;18(4):585-591. (Retrospective study; 671 patients)
39. Krijthe BP, Herringa J, Kors JA et al. Serum potassium levels and the risk of atrial fibrillation: the Rotterdam Study. Int J Cardiol. 2013;168(6):5411-5415. (Retrospective study; 4059 patients)
40. Acker CG, Jonson JP, Palevsky PM, et al. Hyperkalemia in hospitalized patients: causes, adequacy of treatment and the results of an attempt to improve physician compliance with published therapy guidelines. Arch Intern Med. 1998;158(8):917-924. (Retrospective study; 127 patients)
41. Sibbald M, Davies EG, Dorian P, et al. Electrocardiographic interpretation skills of cardiology residents: are they competent? Can J Cardiol. 2014;30(12):1721-1724. (Prospective study; 29 patients)
42. Wrenn KD, Slovis CM, Slovis BS. The ability of physicians to predict hyperkalemia from the ECG. Ann Emerg Med. 1991;20(11):1229-1232. (Prospective observational study)
43. Cohn JN, Kowey PR, Whelton PK, et al. New guidelines for potassium replacement in clinical practice. Arch Intern Med. 2000;160(16):2429-2436. (Consensus review)
44. Macdonald JE, Struthers AD. What is the optimal serum potassium level in cardiovascular patients? J Am Coll Cardiol. 2004;43(2):155-161. (Review)
45. Whelton PK, He J, Cutler JA, et al. Effects of oral potassium on blood pressure: meta-analysis of randomized controlled trials. JAMA. 1997;277(20):1624-1632. (Meta-analysis)
46. Viera AJ, Wouk N. Potassium disorders: hypokalemia and hyperkalemia. Am Fam Physician. 2015;92(6):487-495. (Review)
47. Naljayan M, Kumar S, Steinman T, et al. Hypomagnesemia and hypokalemia: a successful oral therapeutic approach after 16 years of potassium and magnesium intravenous replacement therapy. Clin Kidney J. 2014;7(2):214-216. (Case and review)
48. Mahoney BA, Smith WA, Lo D, et al. Emergency interventions for hyperkalemia. Cochrane Database Syst Rev. 2005;Apr 18(2):CD003235. (Review)
49. Hall AB, Salazar M, Larison DJ. The sequencing of medication in the management of hyperkalemia. J Emerg Nurs. 2009;35(4):339-342. (Review)
50. Allon M, Copkeny C. Albuterol and insulin for treatment of hyperkalemia in hemodialysis patients. Kid Int. 1990;38(5):869-872. (Prospective study, 12 patients)
51. Apel J, Reutrakul S, Baldwin D. Hypoglycemia in the treatment of hyperkalemia with insulin in patients with end stage renal disease. Clin Kidney J. 2014;7(3):248-250. (Retrospective study; 221 patients)
52. Schafer S, Naunheim R, Vijayan A, et al. Incidence of hypoglycemia following insulin based acute stabilization of hyperkalemia treatment. J Hosp Med. 2012;7(3):239-242. (Retrospective study; 219 patients)
53. Chothia MY, Halperin ML, Rensberg MA, et al. Bolus administration of intravenous glucose in the treatment of hyperkalemia: a randomized controlled trial. Nephron Physiol. 2014;126(1):1-8. (Prospective crossover; 10 patients)
54. Allon M, Shanklin N. Effect of bicarbonate administration on plasma potassium in dialysis patients: interactions with insulin and albuterol. Am J Kid Dis. 1996;28(4):508-514. (Prospective crossover study)
55. Sowinski KM, Cronin D, Mueller BA, et al. Subcutaneous terbutaline use in CKD to reduce potassium concentrations. Am J Kidney Dis. 2005;45(6):1040-1045. (Prospective study; 14 patients)
56. Scherr L, Ogden DA, Mead, et al. Management hyperkalemia with a cation exchange resin. N Engl J Med. 1961;264:115- 119. (Prospective study; 32 patients)
57. Batternick J, Lin J, Au Yeung SH, et al. Effectiveness of SPS for short term treatment of hyperkalemia. Can J Hosp Pharm. 2015;68(4):296-303. (Retrospective study; 138 patients)
58. Harel Z, Harel S, Shah P, et al. Gastrointestinal adverse events with SPS use: a systematic review. Am J Med. 2013;126(3):264e9-264e24. (Systematic review; 58 cases)
59. Stavros F, Yang A, Leon A, et al. Characterization of structure and function of ZS-9, a K selective ion trap. PLoS One. 2014;9(12):e114686. (Review article)
60. Ash SR, Singh B, Lavin PT, et al. A phase 2 study on the treatement of hyperkalemia in patients with chronic kidney disease suggests that the selective potassium trap, ZS-9, is safe and efficient. Kidney Int. 2015;88(2):404-411. (Prospective study; 92 patients)
61. Packham DK, Rasmussen HS, Lavin PT, et al. Sodium zirconium cyclosilicate in hyperkalemia. NEJM. 2015;372(3):222- 231. (Prospective randomized controlled trial; 754 patients)
62. Kosiborod M, Rasmussen HS, Lavin P, et al. Effect of sodium zirconium cyclosilicate on potassium lowering for 28 days among outpatients with hyperkalemia. JAMA. 2014;312(12):2233-2233. (Prospective study; 258 patients)
63. Anker SD, Kosiborod M, Zannad F, et al. Maintenance of serum potassium with sodium zirconium cyclosilicate (ZS-9) in heart failure patients: results from a phase 3 randomized, double blind, placebo controlled trial. Eur J Heart Fail. 2015;17(10):1050-1056 (Prospective study; 94 patients)
64. Weir MR, Bakris GL, Bushinsky DA, et al. Patiromer in patients with kidney disease and hyperkalemia receiving RAAS inhibitors. NEJM. 2015;372(3):211-221. (Prospective study; 237 patients)
65. Pitt B, Anker SD, Bushinsky DA, et al. Evaluation of the efficacy and safety of RLY5016, a polymeric potassium binder, in a double blind placebo controlled study in patients with chronic heart failure (the PEARL-HF) trial. Eur Heart J. 2011;32(7):820-828. (Prospective study; 105 patients)
66. Bakris GL, Pitt B, Weir MR, et al. Effect of patiromer on serum potassium level in patients with hyperkalemia and diabetic kidney disease: the AMETHYST-DN randomized clinical trial. JAMA. 2015;314(2):151-160. (Prospective study; 306 patients)
67. Gutzeiller JP, Schneditz D, Huber AR, et al. Increasing blood flow increases K+/V (urea) and potassium removal but fails to improve phosphate removal. Clin Neph. 2003;59(2):103- 136. (Prospective crossover study; 13 patients)
68. Zehnder C, Gutzwiller JP, Huber AR, et al. Low potassium and glucose free dialysis maintains urea but removes potassium. Neph Dial Transplant. 2001;16(1):78-84. (Prospective study; 12 patients)
69. Blaine A, Ract C, Leblanc P, et al. The limits of succinylcholine for critically ill patients. Anesth Analg. 2012;115(4):873- 879. (Prospective observational study; 153 patients)
70. Su J, Fu X, Ma Y, et al. Additional predictive value of serum potassium to thrombosis in myocardial infarction risk score for early malignant ventricular arrhythmias in patients with acute myocardial infarction. Am J Emerg Med. 2012;30(7):1089-1094. (Retrospective study; 468 patients)
71. Grodzinsky A, Goyal A, Gosch K et al. Prevalence and prognosis of hyperkalemia in patients with acute myocardial infarction. Am J Med. 2016;129(8):858-865. (Retrospective study; 38,689 patients)
72. Bismuth C, Gaultier M, Conso F, et al. Hyperkalemia in acute digitalis poisoning: prognostic significance and therapeutic implications. Clin Toxicol. 1973;6(2):153-162.
73. Fontaine B. Periodic paralysis. Adv Genet. 2008;63:3-23. (Review)
74. Venance SL,Cannon SC, Fialho D, et al. The primary periodic paralyses: diagnosis, pathogenesis and treatment. Brain. 2006;129(Pt 1):8-17. (Review)
75. Lin SH, Lin YF, Chen DT, et al. Laboratory tests to determine the cause of hypokalemia and paralysis. Arch Intern Med. 2004;164(14):1561-1566. (Prospective study; 43 patients)
76. Flinn RB, Merrill JP, Welzant WR. Treatment of the oliguric patient with a new sodium exchange resin and sorbitol; a preliminary report. NEJM. 1961 Jan 19;264:111-115. (Prospective study; 16 patients)