Hyperkalemia

Background

High = >5.5meq/L

High! = >6.5meq/L

Diagnosis

• Always consider pseudohyperkalemia (e.g. from hemolysis)

ECG

6.5-7.5 - peaked Ts, inc PR, dec QT

7.5-8.0 - QRS widening, P flattening

10-12 - sine wave, v-fib, heart block

Differential Diagnosis

1. Pseudohyperkalemia
   1. Hemolysis of specimen
   2. Pronged tourniquet use prior to blood draw
   3. Thrombocytosis/leukocytosis
2. Redistribution
   1. Acidemia (DKA)
   2. Cellular breakdown
      1. Rhabdomyolysis/crush injury
      2. Hemolysis
      3. Tumor lysis syndrome
3. Increased total body potassium
   1. Inadequate excretion
      1. Renal caused (acute or chronic renal failure-must have GFR<10)
      2. Hypoaldo
      3. Drug-induced
         1. K sparing diuretics (spironolactone), ACEI, NSAIDs
   2. Excessive intake
      1. Diet
      2. Blood transfusion
4. Misc
   1. Sux, Dig, B-blockers

Treatment

1. Calcium gluconate 1 amp IV (if ECG changes/hypotension/or >7; can give mult times)
   1. Caution in dig-toxic patients!
2. Albuterol neb 2.5mg x 3
3. 10 U reg insulin IV with 1 amp D50W IV now, and 1 amp in 15 min
4. 1 amp NaBicarb IV (over 5 min)
5. Kayexalate 30g PO (may cause volume overload; +/- 50mL sorbitol)
6. Consider dialyisis & ?lasix

Source

7/2/09 Adapted from Tintinalli, Donaldson, Pani