1. Potassium Disorders Ganesh Shidham, MD Associate Professor of Internal Medicine Division of Nephrology

2. K distribution IC fluid 4000 meq 150 meq/L 98% EC fluid 65 meq 4 meq/L 2% Shifts between compartment Rapid within minutes Daily dietary K 100 meq Intestine 10 meq Renal 90 meq Requires Several hours

3. Case 7 A 38 yr old woman with Crohn’s has high output ileostomy. She came to ER with weakness and paresthesias. PE: BP 115/75 (supine) and 105/65 (seated). Ca 5.5 Albumin 3 P 1.3 IV NS plus 80 mEq KCl and IV Sod Bicarb was given. After 24 hrs the orthostatic changes are reversed. BUN and creatinine improves to 20/1.5. However k is still at 2.9. What is the most likely reason for persistent Hypokalemia? 1. Hypocalcemia makes correction of Hypokalemia difficult 2. Patient is Magnesium depleted which prevents K repletion 3. Administration of sod bicarb is shifting K into cells 4. Hypophosphatemia has exacerbated the Hypokalemia 130 8530 2.8182.0

4. Case 7 A 38 yr old woman with Crohn’s has high output ileostomy. She came to ER with weakness and paresthesias. PE: BP 115/75 (supine) and 105/65 (seated). Ca 5.5 Albumin 3 P 1.3 IV NS plus 80 mEq KCl and IV Sod Bicarb was given. After 24 hrs the orthostatic changes are reversed. BUN and creatinine improves to 20/1.5. However k is still at 2.9. What is the most likely reason for persistent Hypokalemia? 1. Hypocalcemia makes correction of Hypokalemia difficult 2. Patient is Magnesium depleted which prevents K repletion 3. Administration of sod bicarb is shifting K into cells 4. Hypophosphatemia has exacerbated the Hypokalemia 130 8530 2.8182.0

5. Hypokalemia: Factors stimulating K secretion 1.Aldosterone 2.High distal sodium delivery 3.High urine flow rate 4.Metabolic alkalosis

6. Hypokalemia and K deficit

8. Hyperkalemia: Drug induced Block Na channel in distal nephron Amiloride, triamterene, trimethoprim, pentamidine Block aldosterone production ACE-I, ARB, NSAIDS, Heparine, Tacrolimus Block aldosterone receptors Spironolactone Block Na-K-ATPase activity in distal nephron Cyclosporine Inhibit ECF to ICF shift Beta blockers K release from ICF to ECF due to cell damage Statins, cocaine, chemotherapy

9. Case 8 52 year old man on dialysis 3 times a week. He missed his last dialysis. Now comes to ER due to weakness. Na 130, K 7.4, Bicarb 16

10. Case 8 (cont.) While awaiting dialysis, he receives IV Ca Gluconate, sod bicarb, Glucose and Insulin, and oral sodium kayexalate. Which of the following is least likely to reduce his serum potassium levels? 1. Sodium Bicarbonate 2. Glucose and Insulin 3. Calcium Gluconate 4. Kayexalate

11. Case 8 (cont.) While awaiting dialysis, he receives IV Ca Gluconate, sod bicarb, Glucose and Insulin, and oral sodium kayexalate. Which of the following is least likely to reduce his serum potassium levels? 1. Sodium Bicarbonate 2. Glucose and Insulin 3. Calcium Gluconate 4. Kayexalate

12. Case 9 36 year old male with advanced HIV is admitted with PCP pneumonia. He continues to use illicit injection drugs. PE - Febrile, BP 110/70. Treatment is initiated with high dose Bactrim, prednisone and oxygen. Urine protein 4+ CPK 250 (On Admission) (Hospital day 3) Likely cause of Hyperkalemia on day 3: 1. Impaired K secretion due to HIV nephropathy 2. Intracellular K release due to Rhabdomyolysis 3. Impaired K secretion due to Bactrim 4. Catabolic effects of Prednisone 136 10215 4240.6 138 10418 6.5220.9

13. Case 9 36 year old male with advanced HIV is admitted with PCP pneumonia. He continues to use illicit injection drugs. PE - Febrile, BP 110/70. Treatment is initiated with high dose Bactrim, prednisone and oxygen. Urine protein 4+ CPK 250 (On Admission) (Hospital day 3) Likely cause of Hyperkalemia on day 3: 1. Impaired K secretion due to HIV nephropathy 2. Intracellular K release due to Rhabdomyolysis 3. Impaired K secretion due to Bactrim 4. Catabolic effects of Prednisone 136 10215 4240.6 138 10418 6.5220.9

14. Treatment of Hyperkalemia MechanismTreatmentOnset of Action Antagonize membrane  -Ca gluconate  Few min effects (30ml of 10% sol.) Redistribution  - Glucose (50 g) & insulin R (10 u)  15 - 30 min. - NaHCO 3 (1-3 amps)  15 - 30 min. -  2 agonists  15 - 30 min. (nebulized albuterol, adult dose: 20 mg) Removal  Kayexalate: enema  60 min (cation exchange resin) oral  120 min Dialysis: HD  few min CAPD after start

15. Thank you for completing this module If you have any questions, I am available. Ganesh.Shidham@osumc.edu