Hyponatremia and Other Critical Electrolyte Abnormalities

1. Hyponatremia and Other Critical Electrolyte Abnormalities Phillip D. Levy, MD, MPH, FACEP Associate Professor and Associate Director of Clinical Research Department of Emergency Medicine Assistant Director of Clinical Research Cardiovascular Research Institute Wayne State University School of Medicine

2. Disclosures • None relevant to this presentation

3. Objectives • To provide a brief review of common electrolyte abnormalities encountered in the EDand discuss basic treatment • To take a closer look at hyponatremia and evolving approaches to management

4. Potassium • Hyperkalemia • Most common life-threatening electrolyte abnormality • Three stage approach to treatment • Membrane stabilization • Shift potassium into cells • Remove potassium from the body

5. Common Causes Pfenning et al. Critical Decisions in Emergency Medicine 2011;10;2-11.

6. Potassium • Hyperkalemia • Most common life-threatening electrolyte abnormality • Threestage approach to treatment • Membrane stabilization • Shift potassium into cells • Remove potassium from the body

8. Typical ECG Changes Pfenning et al. Critical Decisions in Emergency Medicine 2011;10;2-11.

9. Potassium • Hyperkalemia • Most common life-threatening electrolyte abnormality • Threestage approach to treatment • Membrane stabilization • Shift potassium into cells • Remove potassium from the body

10. Potassium • Hyperkalemia • Most common life-threatening electrolyte abnormality • Threestage approach to treatment • Membrane stabilization • Shift potassium into cells • Remove potassium from the body

11. Potassium • Hypokalemia • Often coupled with hypomagnesemia • Frequently asymptomatic • Cramps, weakness • Classic ECG findings

12. Common Causes Pfenning et al. Critical Decisions in Emergency Medicine 2011;10;2-11.

13. Potassium • Hypokalemia • Often coupled with hypomagnesemia • Frequently asymptomatic • Cramps, weakness • Classic ECG findings

14. Potassium • Hypokalemia • Often coupled with hypomagnesemia • Frequently asymptomatic • Cramps, weakness • Classic ECG findings

15. Potassium • Hypokalemia • Replete orally for mild to moderate decreases • Each 0.3 mEq< normal = 100 mEq deficit • Prolonged therapy may be needed for severe cases • Requires concurrent magnesium to move intracellularly

16. Potassium • Hypokalemia • Replete orally for mild to moderate decreases • Each 0.3 mEq< normal = 100 mEq deficit • Prolonged therapy may be needed for severe cases • Requires concurrent magnesium to move intracellularly

17. Potassium • Hypokalemia • Replete orally for mild to moderate decreases • Each 0.3 mEq< normal = 100 mEq deficit • Prolonged therapy may be needed for severe cases • Requires concurrent magnesium to move intracellularly

18. Calcium • Hypercalcemia • Most often caused by parathyroid disease and malignancy • “Bones, moans, groans and stones” • Arrhythmias with concomitant electrolyte abnormalities • Primary treatment is normal saline • Furosemide can help with associated diuresis but no longer routinely recommended • Bisphosphonates = definitive therapy

19. Common Causes Pfenning et al. Critical Decisions in Emergency Medicine 2011;10;2-11.

20. Calcium • Hypercalcemia • Most often caused by parathyroid disease and malignancy • “Bones, moans, groans and stones” • Arrhythmias with concomitant electrolyte abnormalities • Primary treatment is normal saline • Furosemide can help with associated diuresis but no longer routinely recommended • Bisphosphonates = definitive therapy

21. Calcium • Hypercalcemia • Most often caused by parathyroid disease and malignancy • “Bones, moans, groans and stones” • Arrhythmias with concomitant electrolyte abnormalities • Primary treatment is normal saline • Furosemide can help with associated diuresis but no longer routinely recommended • Bisphosphonates = definitive therapy

22. Calcium • Hypocalcemia • Typically caused by hypoalbuminemia • Muscle cramping, paresthesias • Chvostek sign • Trousseau sign • Oral repletion for mild cases, IV for more significant deficits • Ionized calcium level more accurate than total

23. Calcium • Hypocalcemia • Typically caused by hypoalbuminemia • Muscle cramping, paresthesias • Chvostek sign • Trousseau sign • Oral repletion for mild cases, IV for more significant deficits • Ionized calcium level more accurate than total

24. Calcium • Hypocalcemia • Typically caused by hypoalbuminemia • Muscle cramping, paresthesias • Chvostek sign • Trousseau sign • Oral repletion for mild cases, IV for more significant deficits • Ionized calcium level more accurate than total

25. Magenesium • Hypomagnesemia • Typically caused by insufficient dietary intake, GI disorders, and medication effects • Symptoms relatively non-specific • Treatment generally IV • 0.5-2 gm/h • Watch for loss of deep tendon reflexes and development of respiratory depression

26. Magenesium • Hypomagnesemia • Typically caused by insufficient dietary intake, GI disorders, and medication effects • Symptoms relatively non-specific • Treatment generally IV • 0.5-2 gm/h • Watch for loss of deep tendon reflexes and development of respiratory depression

27. Magenesium • Hypomagnesemia • Typically caused by insufficient dietary intake, GI disorders, and medication effects • Symptoms relatively non-specific • Treatment generally IV • 0.5-2 gm/h • Watch for loss of deep tendon reflexes and development of respiratory depression

28. Sodium • Hypernatremia • Hypovolemia most common cause • Also consider diabetes insipidus • Central (deficient production of AVP) • Nephrogenic (diminished response to AVP)

29. Sodium • Hypernatremia • Hypovolemia most common cause • Also consider diabetes insipidus • Central (deficient production of AVP) • Nephrogenic (diminished response to AVP)

30. Sodium • Hypernatremia • Hypovolemic: replace free water deficit • TBW = 0.6 x current weight (kg) • Desired TBW = measured Na x current TBW / normal Na • Body water deficit = desired TBW – current TBW • Diabetes insipidus • Central: DDAVP • Nephrogenic: thiazide diuretic

31. Sodium • Hypernatremia • Hypovolemic: replace free water deficit • TBW = 0.6 x current weight (kg) • Desired TBW = measured Na x current TBW / normal Na • Body water deficit = desired TBW – current TBW • Diabetes insipidus • Central: DDAVP • Nephrogenic: thiazide diuretic

32. Hyponatremia • Most common electrolyte abonormality • Classified by volume status • Hypovolemic hyponatremia • Decrease in total body water with greater decrease in total body sodium • Euvolemichyponatremia • Normal body sodium with increase in total body water • Hypervolemichyponatremia • Increase in total body sodium with greater increase in total body water

33. Hyponatremia • Most common electrolyte abonormality • Classified by volume status • Hypovolemic hyponatremia • Decrease in total body water with greater decrease in total body sodium • Euvolemichyponatremia • Normal body sodium with increase in total body water • Hypervolemichyponatremia • Increase in total body sodium with greater increase in total body water

34. Hyponatremia • Most common electrolyte abonormality • Classified by volume status • Hypovolemic hyponatremia • Decrease in total body water with greater decrease in total body sodium • Euvolemichyponatremia • Normal body sodium with increase in total body water • Hypervolemichyponatremia • Increase in total body sodium with greater increase in total body water

35. Hyponatremia • Most common electrolyte abonormality • Classified by volume status • Hypovolemic hyponatremia • Decrease in total body water with greater decrease in total body sodium • Euvolemichyponatremia • Normal body sodium with increase in total body water • Hypervolemichyponatremia • Increase in total body sodium with greater increase in total body water

36. Hyponatremia • Most common electrolyte abonormality • Classified by volume status • Hypovolemic hyponatremia • Decrease in total body water with greater decrease in total body sodium • Euvolemichyponatremia • Normal body sodium with increase in total body water • Hypervolemichyponatremia • Increase in total body sodium with greater increase in total body water

37. Hyponatremia • Critical diagnostic tests • Urine osmolality • Serum osmolality • Urine sodium concentration

38. Hyponatremia • Subclassified by effective serum osmolality • Hypertonic • Pseudohypernatremia • Isotonic • High protein or lipid concentration • Hypotonic • < 280 mOsm/kg

39. Hyponatremia • Subclassified by effective serum osmolality • Hypertonic • Pseudohypernatremia • Isotonic • High protein or lipid concentration • Hypotonic • < 280 mOsm/kg

40. Hyponatremia • Subclassified by effective serum osmolality • Hypertonic • Pseudohypernatremia • Isotonic • High protein or lipid concentration • Hypotonic • < 280 mOsm/kg

41. Hyponatremia • Subclassified by effective serum osmolality • Hypertonic • Pseudohypernatremia • Isotonic • High protein or lipid concentration • Hypotonic • < 280 mOsm/kg

42. Hypotonic Hyponatremia • Hypovolemic • Caused by GI loss, renal loss , or 3rd spacing • Non-renal: urine sodium < 20 mEq/L • Renal: urine sodium > 20 mEq/L • Treat with IV normal saline

43. Hypotonic Hyponatremia • Hypovolemic • Caused by GI loss, renal loss , or 3rd spacing • Non-renal: urine sodium < 20 mEq/L • Renal: urine sodium > 20 mEq/L • Treat with IV normal saline

44. Hypotonic Hyponatremia • Isovolemic • Glucocorticoid insufficiency • Hypothyroidism • Psychogenic polydipsia • Medications • Amitriptyline, carbamazepine • Diuretic use with potassium depletion • SIADH • Urine sodium > 20 mEq/L • Urine osmolality > 200 mOsm/kg

45. Hypotonic Hyponatremia • Hypervolemic • Heart failure • Liver disease • CKD • Nephrotic syndrome

46. Hypotonic Hyponatremia • Treatment considerations • Acute vs. chronic • Degree of sodium depletion • Mild: 130-134 mEq/L • Moderate: 120-130 mEq/L • Severe: < 120 mEq/L • Symptoms • Neurologic • Underlying cause

47. Hypotonic Hyponatremia • Treatment considerations • Acute vs. chronic • Degree of sodium depletion • Mild: 130-134 mEq/L • Moderate: 120-130 mEq/L • Severe: < 120 mEq/L • Symptoms • Neurologic • Underlying cause

48. Hypotonic Hyponatremia • Treatment considerations • Acute vs. chronic • Degree of sodium depletion • Mild: 130-134 mEq/L • Moderate: 120-130 mEq/L • Severe: < 120 mEq/L • Symptoms • Neurologic • Underlying cause

49. Hypotonic Hyponatremia • Treatment considerations • Acute vs. chronic • Degree of sodium depletion • Mild: 130-134 mEq/L • Moderate: 120-130 mEq/L • Severe: < 120 mEq/L • Symptoms • Neurologic • Underlying cause

50. Hyponatremia and HF 42.5 45.0 Na < 135 mEq/L Na ≥ 135 mEq/L 40.0 34.8 35.0 30.0 25.0 (Days) or (%) 20.0 12.4 P < .0001 15.0 7.1 10.0 6.4 6.0 5.5 3.2 5.0 0.0 Length of In-hospital Post-discharge Death or stay (days) mortality (%) mortality (%) rehospitalization since discharge (%) Gheorghiadeet al. Eur Heart J 2007;28:980-88.