VanderbiltEM.com. ACEP 2013 Electrolyte Emergencies. Mastering Emergency Medicine. Electrolyte Emergency Questions. Electrolyte Emergency Questions

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1 ACEP 2013 Electrolyte Emergencies VanderbiltEM.com Camiron L. Pfennig, M.D. Corey M. Slovis, M.D. Vanderbilt University Medical Center Nashville, TN Mastering Emergency Medicine Secure the ABC s Consider or give NGT Five Causes Five Steps Five Reasons for almost everything Electrolyte Emergency Questions When do you use calcium for Hyperkalemia? How effective is bicarbonate in Hyperkalemia? A normal sized patient has a K of 2.9 meq/l. What is their approximate total body potassium deficit? When is Hypokalemia an emergency? Why is Hypokalemia the number one cause of unexpected death in DKA? Electrolyte Emergency Questions When do you use hypertonic saline for Hyponatremia? Hypercalcemia is best treated by? What is the role of lasix in Hypercalcemia? What dosing of Magnesium makes you an expert? How does 1.5, 1.0, 0.5 make you an expert in Hypophosphatemia? 1

2 What is the number one cause of Hyperkalemia? The Most Common Cause of Hyperkalemia is... You and Me! Hyperkalemia is the Most Dangerous Acute Electrolyte Emergency HyperK = ECG ECG Changes Serum Level What are the 5 ECG Changes Seen in Hyperkalemia Tall Peaked T Loss of P Wave Widened QRS usually > 8 Tall Peaked T-Waves Prolonged P-R Interval Loss of P Wave Widening of QRS Sine Wave 2

3 Hyperkalemia Five Most Common Causes Pseudo Hyperkalemia CRF Acidosis Cell Death Rhabdomyolysis Burn Crush Tumor Lysis Syndrome Hemolysis Drugs Hyperkalemia 5 Benign Causes ACE Inhibitors Angiotensin Receptor Blockers NSAIDS, COX-2 Inhibitors Potassium Sparing Diuretics Bactrim Especially in the elderly with Especially in those with mild renal insufficiency When do you use calcium for Hyperkalemia? A Hyperkalemic Emergency is defined as a wide QRS Only give calcium if... there is a wide QRS 3

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5 Calcium = Emergency = Wide QRS Calcium Tricks Cells Calcium Does NOT Affect Levels Calcium in Hyperkalemia Tricks Cell Recreates Electrical Gradient Temporary, lasts only 5-20 minutes Dose is 5-20 cc CaCl IV Potentially Dangerous Be sure before using! CaCl X 1,000,000 Ca Gluconate 5

6 CaCl 13.6 meq/10cc More sclerosing Adults Acute Emergency Ca Gluconate 4.6 meq/10cc Less sclerosing Kids Chronic Slow Infusion Only give calcium if... there is a wide QRS Am J Med Sci 2012;Dec 18: episodes of true hyperkalemia > 50% of original sample was excluded for pseudohyperk ACE I #1 drug; Bactrim #2 Meds often not stopped 50% of patients with K > 6.5 had no ECG s Calcium use NOT correlated to any ECG s Bicarbonate For Hyperkalemia How effective is bicarbonate in Hyperkalemia? (1) HCO 3 (3) K + (2) H + (1) As HCO 3 is added to serum (2) H + from cell will move extracellularly to buffer alkali load (3) K + will move intracellularly to maintain the cell s electroneutrality. 6

7 Potassium Lowering Effects Bicarbonate is Great in Hyperkalemia but only if: The Patient is Acidotic Bicarb Epi Glucose/Insulin HD Amer J Kidney Disease 1991;18: Steps in Treating Hyperkalemia Reverse electrical effects Drive potassium into the cells Remove potassium from the body STEP 1: Treating Hyperkalemia Reversing Electrical Effect Calcium Chloride 5 10 cc of 10% CaCl No more than 20 ccs STEP 2: Treating Hyperkalemia Removing K from the Body Glucose and Insulin 2 amps of D 50 % 10 units regular insulin Beta Agonist Mask Bicarbonate if acidotic 1 2 amps of NaHCO 3 Consider Saline Bolus 200 cc NSS STEP 3: Treating Hyperkalemia Removing K from the Body Forced Diuresis cc/hr NaCl Supplemented with Lasix Ion Exchange Resin 30 60G Kayexalate Dialysis Hemodialysis &/or Peritoneal 7

8 Colonic Necrosis reported All used 70% Sorbitol J Am Soc Nephrol 2010;21: Why is Hypokalemia the number one cause of unexpected death in DKA? Use 35% PO; no enemas Does not work for hours Five Therapies to Consider in DKA Volume Insulin Potassium... Bicarbonate Phosphate Driving K into the Cell Glu + Insulin Bicarb Volume Beta Agonist Magnesium Treating DKA 8.7% of 219 patients got hypoglycemic post therapy for hyperkalemia 2.3% had glucose values < 40 J Hosp Med 2012;7: Almost all severe patients had CRF or HD 8

9 NEJM 2012;366:1824 NEJM 2012;366:1824 V J Cardio Med 2008;9:210 9

10 J Cardio Med 2008;9:210 J Cardio Med 2008;9:210 Hyperkalemia Treatments 5 Key Concepts Calcium Bicarb Glu/Insulin Beta Agonists Volume Wide QRS Acidosis Hypoglycemia Benign and Easy Selected Cases Hypokalemia Hypokalemia - 5 Most Common Causes Decreased Intake Chronic ETOH or Malnutrition Increased losses Urine Non K, Non Mag Sparing Diuretics S/P Vomiting GI Chronic Diarrhea or Laxative Abuse Intracellular Shift Hyperventilation or Metabolic Alkalosis 5 ECG Changes Hypokalemia Loss of T Wave U Waves Prolonged Q-T Torsades, VT, VF Diffuse, Nonspecific ST and T Wave Changes 10

11 Annals of EM 1990 QT 265 QTcB 393 QTcF

12 When is Hypokalemia an Emergency? QT = 500 msec 12

13 Hypokalemia Beware Prolonged Q-T Severe or Refractory Hypokalemia Always Equals? Hypomagnesaemia A normal sized patient has a K of 2.9 meq/l. What is their approximate total body deficit? American Heart J

14 Total Body Potassium Deficit: Use MORE Than You Think Every 0.3 meq/l fall below 3.5 meq/l requires: 100 meq of KCL Hypokalemia Treatments 5 Key Concepts Usually Asymptomatic Repletion takes more than you think meq/hr IV is safe Hyponatremia Use PO Too HypoK = HypoMg Hyponatremia Most patients are stable and require no emergency therapy. Most common cause is diuretic use with low salt diet in CHF. Severe or symptomatic patients require immediate therapy with NSS or HSS. How quickly can you safely raise someone s serum sodium? 14

15 When do you use Hypertonic Saline for Hyponatremia? Correct Patients At a Rate of 0.5 meq/hr or less Never Change Serum Na Level by More Than meq/day Why not raise patient s serum sodium faster? Central Pontine Myelinolysis (CPM) Demyelinating disease of pons and CNS Flaccid paralysis, dysarthia, hypotension Alcoholics, malnourished, severely ill Ann Intern Med Caused by too rapid correction May be seen 1 to 2 days after correction 15

16 AMS Status Seizure Vital Signs Toxic Metabolic Structural Infectious Psychiatric Vital Signs Toxic-Metabolic Structural Infectious Epilepsy Hypertonic Saline a. Indications b. In order to use, Serum Sodium is usually - c. What concentration? Hypertonic Saline d. At what rate? e. For how long? Hypertonic Saline a. Indications Seizures Coma Focal Findings b. In order to use, Serum Sodium is usually 100 meq 110 meq d. At what rate? e. For how long? Hypertonic Saline 100 cc over 10 min. 100 cc over next 50 min. Treat for 1 hour c. What concentration? 3 % 16

17 Give seizing HypoNatremic patients 3% Hypertonic Saline Hypernatremia Hypernatremia = Dehydration J Emerg Med 2013; 19 yo, no PMH, with AMS Drank 32 oz of soy sauce Equates to 10+ tablespoons of salt Serum sodium 177 mg/l ph 7.14, comatose, seizures > 10 tablespoons of NaCI Treatment + Survival 6L D 5 W over 30 minutes 5.2L D 5 W over next 24 hours 9 day post admission WNL Hypercalcemia MRI WNL, no CPM Rapid rise = Rapid fall 17

18 Hypercalcemia Hypercalcemia = When do you give Lasix? Hypercalcemia = Saline Best real therapy = Saline NSS inhibits proximal reabsorption of Ca NSS wide open until perfusion is WNL Continue NSS at cc/hr What is the role of Lasix in Hypercalcemia? Titrate based on age and renal function Follow cardio-pulmonary status Lasix Lasix inhibits distal Ca reabsorption Once volume status secure only! 40 mg I.V. Repeat mg q 2H to maintain I/O balance Ann Intern Med 2008;149: How effective is Lasix for Hypercalcemia? Literature search Only 14 articles found Most recent article 25 years old 18

19 Bisphosphonates Ann Intern Med 2008;149: No evidence to support use or efficacy of lasix in hypercalcemia Hydration with NSS and immediate biphosphonate therapy is the treatment of choice Reserve lasix for volume overload Blocks bone absorption Chemical analogues of pyrophosphate Inhibits activity of osteoclasts Takes days to lower Calcium completely Not an ED decision Hypercalcemia Biggest ED Rx Errors Lasix before rehydration Too much saline Hypercalcemia Treatments 5 Key Concepts Secure ABC s (and consider NGT Saline Lasix Follow K and Mg Call internist/oncologist Magnesium 19

20 Serum Magnesium Levels Inaccurate Snap Shot Expensive Silly HypoK = HypoMag 20

21 Dose of Magnesium What dosing of Magnesium makes you an expert? Loading Dose 1-2 Grams over 0-60 minutes except eclampsia Maintenance Dose 0.5 Gram per hour Load with 1 2 grams over 0 60 minutes Maintenance infusion is gram per hour Magnesium Dosing 0.5 Grams/hour Relatively uncommon Am J Emerg Med 2000;18: Specific patient groups at high risk ED MDs need to know therapy 21

22 ED Patients Most Likely to Have Hypophosphatemia Who is at highest risk for symptomatic Hypophosphatemia? When are the most crucial times to think about Hypophosphatemia? Alcohol Withdrawal Alcoholic Ketoacidosis Diabetic Ketoacidosis Malnourished COPD Chronic Malnourished with Acute Hyperventilation Malnourished COPD Severe Hypophosphatemia Cardiac Decreased Contractility How does 1.5, 1.0, 0.5 make you an expert in Respiratory Hypophosphatemia? Decreased Ventilation Musculoskeletal Rhabdomyolysis Hypophosphatemia Key Values 1 cc of K 2 PO 4 Below or less ½ cc / hr Consider Therapy Always symptomatic Best rate for K 2 PO meq of K + 3 mmol of PO 4 = 93 mg PO 4 22

23 Usual Dosing ½ cc/hr of K 2 PO 4 Phosphate K 2 PO 4 Administration meq of K + 3 mmol of PO 4 = 93 mg PO 4 ½ cc/hr of K 2 PO Consider therapy 1.0 Symptomatic 0.5 Usual cc/hr Summary Number One Cause of HyperK= NOT HyperK = ECG Only give calcium if... there is a wide QRS 23

24 Bicarb only if... Acidotic HypoK = HypoMag If you give K... You must give Mag Don t raise Sodium by more than meq/hr Only give Hypertonic Saline if: Sodium below 120 and: Seizures Coma or AMS Focal Findings Only give Hypertonic Saline for how long?... 1 hour 100 cc over 10 minutes 100 cc over next 50 minutes 24

25 In Hypo and Hyper Natremia Hypotension Trumps... Sodium values Hypercalcemia = Saline The loading dose of Magnesium is 1-2 grams over 0-60 min The Usual Hourly Infusion of Magnesium is 0.5 grams/hr. VanderbiltEM.com SECURE THE ABC S 25