Download - Electrolytes Disturbances
Electrolytes DisturbancesJamal A. Alhashemi, MBBS, MSc, FRPC, FCCP, FCCM
Professor of Anesthesiology & Critical Care MedicineFaculty of Medicine, King Abdulaziz University
Principles of Electrolyte Disturbances
Implies an underlying disease process Treat the electrolyte change, but seek the underlying causeClinical 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
Etiology – renal loss, extrarenal loss, transcellular shift, decreased intakeManifestations – cardiac, neuromuscular, gastrointestinalDeficit poorly estimated by serum levels
Hypokalemia
Titrate administration of K+ against serum level and manifestations
Correct hypomagnesemia
ECG monitoring with emergent administration
Allowable maximum iv dose per hour controversial
Treat hypokalemia urgently in acidosis
Hypokalemia
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Hyperkalemia
Etiology – renal failure, transcellular shifts, cell death, drugsManifestations – cardiac, neuromuscular
Hyperkalemia – Treatment
Stop intakeGive calcium for cardiac toxicityShift K+ into cell – glucose + insulin, NaHCO3, inhaled -agonist
Remove from body – diuretics, sodium polystyrene sulfonate, dialysis
Hyperkalemia
Hyponatremia
Hypo-osmolar hyponatremia Euvolemic Hypovolemic Hypervolemic
Normo- or hyperosmolar hyponatremia Pseudohyponatremia
Manifestations – neurologic, muscular, gastrointestinal
Hyponatremia – TreatmentHypovolemic Na – give normal saline, rule out adrenal insufficiencyHypervolemic Na – increase free water lossEuvolemic hyponatremia Restrict free water intake Increase free water loss Normal or hypertonic saline
Correct slowly due to possibility of demyelinating syndromes
Hyponatremia
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Hypernatremia
Etiology – H2O loss, H2O intake, Na intake
Manifestations – neurologic, muscular
H2O deficit (L) =
[ 0.6 wt (kg) ] [ obs Na - 1 ] 140
Hypernatremia – Treatment
Provide intravascular volume replacement
Consider giving one-half of free H2O deficit initially
Reduce Na cautiously: 0.5-1.0 mmol/L/hr
Secondary neurologic syndromes with rapid correction
Hypernatremia
Other Electrolyte DeficitsCa, PO4, Mg
May produce serious but nonspecific cardiac, neuromuscular, respiratory, and other effectsAll are primarily intracellular ions, so deficits difficult to estimateTitrate replacement against clinical findings
Other Electrolyte Disorders
Hypocalcemia Calcium chloride or gluconate Bolus + continuous infusion
Hypercalcemia Rehydration with normal saline Loop diuretics
Other Electrolyte Disorders
Hypophosphatemia IV replacement for level < 1 mg/dL (0.32
mmol/l)Hypomagnesemia Emergent administration over 5–10 mins Less urgent administration over
10–60 mins