Objectives

Review causes and clinical manifestations of
severe electrolyte disturbances

Outline emergent management of electrolyte
disturbances

Recognize acute adrenal insufficiency and
appropriate treatment

Describe management of severe hyperglycemic
syndromes
Principles of Electrolyte Disturbances

Implies an underlying disease process

Treat the electrolyte change, but seek the cause

Clinical manifestations usually not specific to a
particular electrolyte change, e.g., seizures,
arrhythmias
Principles of Electrolyte Disturbances

Clinical manifestations determine urgency of
treatment, not laboratory values

Speed and magnitude of correction
dependent
on clinical circumstances

Frequent reassessment of electrolytes
required
Hypokalemia
Neuromuscular manifestations (weakness,
fatigue, paralysis, respiratory dysfunction)
 GI (constipation, ileus)
 Nephrogenic DI
 ECG changes (U waves, flattened T waves)
 Arrhythmias

Hypokalemia

Spurious hypokalemia
 Marked
leukocytosis
 A dose of insulin right before the blood draw

Redistribution hypokalemia
 Alkalosis
(K decreases .3 for every .1 increase in
pH)
 Increased Beta2 adrenergic activity
 Theophylline toxicity
 Familial
Hypokalemia

Extrarenal depletion
 diarrhea
 laxative
abuse
 sweat losses
 fasting or inadequate intake
Hypokalemia

Renal potassium depletion
 urine
potassium > 20 mEq/24 hrs
 spot urine with > 20 mEq K/gram creatinine
 classified whether they occur with a metabolic
alkalosis
vomiting/NG suction
 diuretic tx
 Mineralocorticoid excess syndromes

Hypokalemia

Renal losses
 metabolic
acidosis
RTA Type I and II
 DKA
 Carbonic anhydrase inhibitor therapy
 Ureterosigmoidostomy

 No
acid-base disorder
Mg deficiency
 Drugs

Hyperkalemia
Severe hyperkalemia is a medical emergency
 Neuromuscular signs (weakness, ascending
paralysis, respiratory failure)
 Progressive ECG changes (peaked T waves,
flattened P waves, prolonged PR interval,
idioventricular rhythm and widened QRS
complex, “sine wave” pattern, V fib)

Hyperkalemia

Etiology – renal failure,
transcellular shifts, cell
death, drugs,
pseudohyperkalemia

Manifestations –
cardiac, neuromuscular
Hyperkalemia

Impaired potassium secretion
 Aldosterone
deficiency
adrenal failure
 Syndrome of hyporeninemic hypoaldosteronism (SHH)
 tubular unresponsiveness

 Renal

failure
GFR < 10 -20% of normal
Hyperkalemia

Treatment
 Stop
potassium!
 Get and ECG
 Hyperkalemia with ECG changes is a medical
emergency
Hyperkalemia

Treatment
 First
phase is emergency treatment to counteract
the effects of hyperkalemia

IV Calcium
 Temporizing
treatment to drive the potassium into
the cells
glucose plus insulin
 Beta2 agonist
 NaHCO3

Hyperkalemia

Treatment
 Therapy
directed at actual removal of potassium
from the body
sodium polystyrene sulfonate (Kayexalate)
 dialysis

 Determine
and correct the underlying cause
Body Fluid Distribution
ECF
Vascular
Interstitial
ICF
Intracellular
TOTAL
Water
(L)
[Na]
(mmol/L)
[K]
(mmol/L)
3
16
140
140
5
5
23
10
150
42