Electrolyte Disturbances

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• Electrolyte Disturbances

Pediatric Critical Care Medicine Emory
University Childrens Healthcare of Atlanta
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Objectives

• Recognize common fluid and electrolyte disorders
• Clinical presentations
• Management

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Basic Metabolic Panel

• Na Cl- BUN Ca
• Glu Mg
• K CO3-- Cr Phos--

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Basic Metabolic Panel

• Na Cl- BUN Ca
• Glu Mg
• K CO3-- Cr Phos--

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Sodium (Na)

• Bulk cation of extracellular fluid ? change in
  SNa reflects change in total body Na
• Principle active solute for the maintenance of
  intravascular interstitial volume
• Absorption throughout the GI system via active
  Na,K-ATPase system
• Excretion urine, sweat feces
• Kidneys are the principal regulator

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Sodium (Na)

• Kidneys are the principal regulator
• 2/3 of filtered Na is reabsorbed by the proximal
  convoluted tubule, increase with contraction of
  extracellular fluid
• Countercurrent system at the Loop of Henle is
  responsible for Na (descending) water
  (ascending) balance active transport with Cl-
• Aldosterone stimulates further Na re-absorption
  at the distal convoluted tubules the collecting
  ducts
• lt1 of filtered Na is normally excreted but can
  vary up to 10 if necessary

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Sodium (Na)

• Normal SNa 135-145
• Major component of serum osmolality
• Sosm (2 x Na) (BUN / 2.8) (Glu / 18)
• Normal 285-295
• Alterations in SNa reflect an abnormal water
  regulation

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Sodium (Na)

• Hypernatremia Causes
• Excessive intake
• Improperly mixed formula
• Exogenous bicarb, hypertonic saline, seawater
• Water deficit
• Central nephrogenic DI
• Increased insensible loss
• Inadequate intake

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Sodium (Na)

• Hypernatremia Causes
• Water and sodium deficit
• GI losses
• Cutaneous losses
• Renal losses
• Osmotic diuresis mannitol, diabetes mellitus
• Chronic kidney disease
• Polyuric ATN
• Post-obstructive diuresis

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Sodium (Na)

• Hypernatremia Clinical presentation
• Dehydration
• Doughy feel to skin
• Irritability, lethargy, weakness
• Intracranial hemorrhage
• Thrombosis renal vein, dura sinus

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Sodium (Na)

• Hypernatremia Treatment
• Rate of correction for Na 1-2 mEq/L/hr
• Calculate water deficit
• Water deficit 0.6 x wt (kg) x (current
  Na/140) 1
• Rate of correction for calculated water deficit
• 50 first 12-24 hrs
• Remaining next 24 hrs

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Sodium (Na)

• Hyponatremia
• Nalt135
• Seizure threshold 125
• lt120 life threatening

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Sodium (Na)

• Hyponatremia Etiology
• Hypervolemic
• CHF Cirrhosis
• Nephrotic syndrome Hypoalbuminemia
• Septic capillary leak
• Hypovolemic
• Renal losses Cerebral salt wasting
• Extra-renal losses aldosterone effect
• GI losses
• Third spacing

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Sodium (Na)

• Hyponatremia Etiology
• Euvolemic hyponatremia
• SIADH
• Glucocorticoid deficiency
• Hypothyroidism
• Water intoxication
• Psychogenic polydipsia
• Diluted formula
• Beer potomania
• Pseudo-hyponatremia
• Hyperglycemia
• SNa decreased by 1.6/100 glucose over 100

-
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Sodium (Na)

• Hyponatremia Clinical presentation
• Cellular swelling due to water shifts into cells
• Anorexia, nausea, emesis, malaise, lethargy,
  confusion, agitation, headache, seizures, coma
• Chronic hyponatremia better tolerated

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Sodium (Na)

• Hyponatremia Treatment
• Rapid correction ? central pontine myelinolysis
• Goal 12 mEq/L/day
• Fluid restriction with SIADH
• Hyponatremic seizures
• Poorly responsive to anti-convulsants
• Hypertonic saline
• Need to bring Na to above seizure threshold

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Sodium (Na)

• Fill in the blanks

Urine Output SerumNa UrineNa Serum Osm UrineOsm
DI
SIADH
CSW
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Sodium (Na)

• Fill in the blanks

Urine Output SerumNa UrineNa Serum Osm UrineOsm
DI
SIADH
CSW
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Sodium (Na)

• Fill in the blanks

Urine Output SerumNa UrineNa Serum Osm UrineOsm
DI
SIADH
CSW
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Sodium (Na)

• Fill in the blanks

Urine Output SerumNa UrineNa Serum Osm UrineOsm
DI
SIADH
CSW
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Sodium (Na)

• Fill in the blanks

Urine Output SerumNa UrineNa Serum Osm UrineOsm
DI
SIADH
CSW
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Sodium (Na)

• Fill in the blanks

Urine Output SerumNa UrineNa Serum Osm UrineOsm
DI
SIADH
CSW
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Sodium (Na)

• Fill in the blanks

Urine Output SerumNa UrineNa Serum Osm UrineOsm
DI
SIADH
CSW
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Sodium (Na)

• Fill in the blanks

Urine Output SerumNa UrineNa Serum Osm UrineOsm
DI
SIADH
CSW
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Sodium (Na)

• Fill in the blanks

Urine Output SerumNa UrineNa Serum Osm UrineOsm
DI
SIADH
CSW
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Sodium (Na)

• Fill in the blanks

Urine Output SerumNa UrineNa Serum Osm UrineOsm
DI
SIADH
CSW
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Sodium (Na)

• Fill in the blanks

Urine Output SerumNa UrineNa Serum Osm UrineOsm
DI
SIADH
CSW
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Sodium (Na)

• Fill in the blanks

Urine Output SerumNa UrineNa Serum Osm UrineOsm
DI
SIADH
CSW
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Sodium (Na)

• Fill in the blanks

Urine Output SerumNa UrineNa Serum Osm UrineOsm
DI
SIADH
CSW
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Sodium (Na)

• Fill in the blanks

Urine Output SerumNa UrineNa Serum Osm UrineOsm
DI
SIADH
CSW
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Sodium (Na)

• Fill in the blanks

Urine Output SerumNa UrineNa Serum Osm UrineOsm
DI
SIADH
CSW
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Sodium (Na)

• Fill in the blanks

Urine Output SerumNa UrineNa Serum Osm UrineOsm
DI
SIADH
CSW
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Basic Metabolic Panel

• Na Cl- BUN Ca
• Glu Mg
• K CO3-- Cr Phos--

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Potassium (K)

• Normal range 3.5-4.5
• Largely contained intra-cellular ? SK does not
  reflect total body K
• Important roles contractility of muscle cells,
  electrical responsiveness
• Principal regulator kidneys

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Potassium (K)

• Daily requirement 1-2 mEq/kg
• Complete absorption in the upper GI tract
• Kidneys regulate balance
• 10-15 filtered is excreted
• Aldosterone increase K decrease Na excretion
• Mineralocorticoid glucocorticoid ? increase K
  decrease Na excretion in stool

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Potassium (K)

• Solvent drag
• Increase in Sosmo ? water moves out of cells ? K
  follows
• 0.6 SK / 10 of Sosmo
• Evidence of solvent drag in diabetic ketoacidosis
• Acidosis
• Low pH ? shifts K out of cells (into serum)
• Hi pH ? shifts K into cells
• 0.3-1.3 mEq/L K change / 0.1 unit change in pH
  in the opposite direction

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Potassium (K)

• Hyperkalemia
• gt6.5 life threatening
• Potential lethal arrhythmias

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Potassium (K)

• Hyperkalemia Causes
• Spurious
• Difficult blood draw ? hemolysis ? false reading
• Increase intake
• Iatrogenic IV or oral
• Blood transfusions

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Potassium (K)

• Hyperkalemia Causes
• Decrease excretion
• Renal failure
• Adrenal insufficiency or CAH
• Hypoaldosteronism
• Urinary tract obstruction
• Renal tubular disease
• ACE inhibitors
• Potassium sparing diuretics

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Potassium (K)

• Hyperkalemia Causes
• Trans-cellular shifts
• Acidemia
• Rhadomyolysis Tumor lysis syndrome Tissue
  necrosis
• Succinylcholine
• Malignant hyperthermia

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Potassium (K)

• Hyperkalemia Clinical presentation
• Neuromuscular effects
• Delayed repolarization, faster depolarization,
  slowing of conduction velocity
• Paresthesias ? weakness ? flaccid paralysis

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Potassium (K)

• Hyperkalemia Clinical presentation
• EKG changes
• 6 peak T waves
• 7 increased PR interval
• 8-9 absent P wave with widening QRS complex
• Ventricular fibrillation
• Asystole

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Potassium (K)
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Potassium (K)

• Hyperkalemia Treatment
• Lower K temporarily
• Calcium gluconate 100mg/kg IV
• Bicarb 1-2 mEq/kg IV
• Insulin glucose
• Insulin 0.05 u/kg IV D10W 2ml/kg then
• Insulin 0.1 u/kg/hr D10W 2-4 ml/kg/hr
• Salbutamol (ß2 selective agonist) nebulizer

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Potassium (K)

• Hyperkalemia Treatment
• Increase elimination
• Hemodialysis or hemofiltration
• Kayexalate via feces
• Furosemide via urine

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Potassium (K)

• Hypokalemia
• lt2.5 life threatening
• Common in severe gastroenteritis

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Potassium (K)

• Hypokalemia Causes
• Distribution from ECF
• Hypokalemic periodic paralysis
• Insulin, ?-agonists, catecholamines, xanthine
• Decrease intake
• Extra-renal losses
• Diarrhea
• Laxative abuse
• Perspiration
• Excessive colas consumption

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Potassium (K)

• Hypokalemia Causes
• Renal losses
• DKA
• Diuretics thiazide, loop diuretics
• Drugs amphotericin B, Cisplastin
• Hypomagnesemia
• Alkalosis
• Hyperaldosteronism
• Licorice ingestion
• Gitelman Bartter syndrome

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Potassium (K)

• Hypokalemia Presentation
• Usually asymptomatic
• Skeletal muscle weakness cramps respiratory
  failure
• Flaccid paralysis hyporeflexia
• Smooth muscle constipation, urinary retention
• ECG changes
• Flattened or inverted T-wave
• U wave prolonged repolarization of the Purkinje
  fibers
• Depressed ST segment and widen PR interval
• Ventricular fibrillation can happen

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Potassium (K)

• Hypokalemia
• - Flattened or inverted T-wave
• - U wave prolonged repolarization of the
  Purkinje fibers
• - Depressed ST segment and widen PR interval
• - Ventricular fibrillation can happen

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Potassium (K)

• Hypokalemia Treatment
• Address the causes underlying condition
• Dietary supplements leafy green vegetables,
  tomatoes, citrus fruits, oranges or bananas
• Oral K replacement preferred
• IV KCl 0.5-1 mEq/kg over 1 hr (rate of 10
  mEq/hr)
• K Acetate or K Phos as alternative
• Add K sparing diuretics
• Correct hypomagnesemia

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Basic Metabolic Panel

• Na Cl- BUN Ca
• Glu Mg
• K HCO3-- Cr Phos--

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Bicarb (HCO3--)

• Normal range 25-35
• Important buffer system in acid-base homeostasis
• Increased in metabolic alkalosis or compensated
  respiratory acidosis
• Decreased in metabolic acidosis or compensated
  respiratory alkalosis
• 0.15 pH change/10 change in bicarb in
  uncompensated conditions

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Bicarb (HCO3--)

• Metabolic acidosis
• Anion gap Na (Cl bicarb)
• Normal range 12 /- 2

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Bicarb (HCO3--)

• Metabolic acidosis causes for increase anion gap
• M
• U
• D
• P
• I
• L
• E
• S

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Bicarb (HCO3--)

• Metabolic acidosis causes for increase anion
  gap
• Methanol
• Uremia
• DKA
• Paraldehyde or propylene glycol
• Isoniazid
• Lactic acidosis
• Ethylene glycol
• Salicylates

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Bicarb (HCO3--)

• Metabolic acidosis causes for normal anion gap
• Diarrhea
• Pancreatic fistula
• Renal tubular acidosis or renal failure
• Intoxication ammonium chloride, Acetazolamide,
  bile acid sequestrants, isopropyl alcohol
• Glue sniffing
• Toluene

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Bicarb (HCO3--)

• Metabolic acidosis Clinical presentation
• Chest pain, palpitation
• Kussmaul respirations
• Hyperkalemia
• Neuro lethargy, stupor, coma, seizures
• Cardiac arrhythmias, decreased response to
  Epinephrine, hypotension

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Bicarb (HCO3--)

• Metabolic acidosis Treatment
• pHlt7.1, risk of arrhythmias
• IV bicarb
• Dialysis

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Bicarb (HCO3--)

• Metabolic alkalosis Causes
• Chloride responsive
• Compensated respiratory acidosis
• Diuretics ? contraction alkalosis
• Vomiting
• Chloride resistant
• Retention of bicarb, shift hydrogen ion into IC
  space
• Alkalotic agents
• Hyperaldosteronism

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Basic Metabolic Panel

• Na Cl- BUN Ca
• Glu Mg
• K CO3-- Cr Phos--

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Glucose

• Hypoglycemia Causes
• Complication of DM therapies
• Hyperinsulinemia
• Inborn errors of metabolism
• Alcohol
• Starvations
• Infections, organ failure

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Glucose

• Hypoglycemia Clinical presentation
• Adrenergic
• Shakiness, anxiety, nervousness, palpitations,
  tachycardia
• Sweating, pallor, coldness, clamminess
• Glucagon
• Hunger, borborygmus, nausea, vomiting, abd.
  Discomfort
• Headache
• Neuroglycopenic
• AMS, fatigue, weakness, lethargy, confusion,
  amnesia.
• Ataxia, incoordination, slurred speech

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Glucose

• Hypoglycemia Treatments
• 0.5-1 g/kg of dextrose
• 5-10 ml/kg of D10W
• 2-4 ml/kg of D25W
• Max 1 amp (50 g)

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Basic Metabolic Panel

• Na Cl- BUN Ca
• Glu Mg
• K CO3-- Cr Phos--

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Calcium

• Normal range 8.8-10.1 with half bound to albumin
• Ionized (free or active)calcium 4.4-5.4
  relevant for cell function
• Majority is stored in bone
• Hypoalbuminemia ? falsely decreased calcium
• Cac Cam 0.8 x (Albn Alb m)

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Calcium

• Roles
• Coagulation
• Cellular signals
• Muscle contraction
• Neuromuscular transmission
• Controlled by parathyroid hormone and vitamin D

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Calcium

• Hypercalcemia Causes
• Excess parathyroid hormone, lithium use
• Excess vitamin D
• Malignancy
• Renal failure
• High bone turn over
• Prolonged immobilization
• Hyperthyroidism
• Thiazide use, vitamin A toxicity
• Pagets disease
• Multiple myeloma

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Calcium

• Hypercalcemia Clinical presentation
• Groans constipation
• Moans psychic moans (fatigue, lethargy,
  depression)
• Bones bone pain
• Stones kidney stones
• Psychiatric overtones depression confusion
• Fatigue, anorexia, nausea, vomiting, pancreatitis
• ECG short QT interval, widened T wave

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Calcium

• Hypercalcemia Treatments
• Fluid diuretics
• Forced diuresis
• Loop diuretic
• Oral supplement biphosphate or calcitonine
• Glucocorticoids
• Dialysis

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Calcium

• Hypocalcemia Causes
• Eating disorder
• Hungry bone syndrome
• Ingestion mercury , excessive Mg
• Chelation therapy EDTA
• Absent of PTH
• Ineffective PTH CRF, absent or ineffective
  vitamin D, pseudohypoparathyroidism
• Deficient in PTH acute hyperphos TLS, ARF,
  Rhabdo
• Blood transfusions

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Calcium

• Hypocalcemia Clinical presentation
• Neuromuscular irritability
• Paresthesias oral, perioral and acral, tingling
  or pin needles
• Tetany (Chvostek Trousseau signs)
• Hyperreflexia
• Laryngospasm
• Jittery, poor feedings or vomiting in newborns
• ECG changes prolonged QT intervals

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Calcium

• Hypocalcemia Treatments
• Supplements
• IV gluconate or chloride with EKG change
• Oral calcium with vitamin D

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Basic Metabolic Panel

• Na Cl- BUN Ca
• Glu Mg
• K CO3-- Cr Phos--

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Magnesium

• Normal range 1.5-2.3
• 60 stored in bone
• 1 in extracellular space
• Necessary cofactor for many enzymes
• Renal excretion is primary regulation

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Magnesium

• Hypermagnesemia Causes
• Hemolysis
• Renal insuficiency
• DKA, adrenal insufficiency, hyperparathyroidism,
  lithium intoxication

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Magnesium

• Hypermagnesemia Clinical presentation
• Weakness, nausea, vomiting
• Hypotension, hypocalcemia
• Arrhythmia and asystole
• 4.0 mEq/L hyporeflexia
• gt5 prolonged AV conduction
• gt10 complete heart block
• gt13 cardiac arrest

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Magnesium

• Hypermagnesemia Treatments
• Calcium infusion
• Diuretics
• Dialysis

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Magnesium

• Hypomagnesemia Causes
• Alcoholism malnutrition diarrhea Thiamine
  deficiency
• GI causes Crohns, UC, Whipples disease, celiac
  sprue
• Renal loss Bartters syndrome, postobstructive
  diuresis, ATN, kidney transplant
• DKA
• Drugs
• Loop and thiazide diuretics
• Abx aminoglycoside, ampho B, pentamidine, gent,
  tobra
• PPI
• Others digitalis, adrenergic, cisplastin,
  ciclosporine

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Magnesium

• Hypomagnesemia Clinical presentation
• Weakness, muscle cramps
• Cardiac arrhythmias
• Prolonged PR, QRS QT
• Torsade de pointes
• Complete heart block cardiac arrest with level
  gt15
• CNS irritability, tremor, athetosis, jerking,
  nystagmus
• Hallucination, depression, epileptic fits, HTN,
  tachycardia, tetany

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Magnesium

• Hypomagnesemia Treatments
• Oral or IV supplement
• Correct on going loss

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Basic Metabolic Panel

• Na Cl- BUN Ca
• Glu Mg
• K CO3-- Cr Phos--

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Phosphorus

• Normal range 2.3 - 4.8
• Most store in bone or intracellular space
• lt1 in plasma
• Intracellular major anion, most in ATP
• Concentration varies with age, higher during
  early childhood
• Necessary for cellular energy metabolism

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Phosphorus

• Hyperphosphatemia
• Causes
• Hypoparathyroidism
• Chronic renal failure
• Osteomalacia
• Presentations
• Ectopic calcification
• Renal osteodystrophy
• Treatments
• Dietary restriction
• Phosphate binder

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Phosphorus

• Hypophosphatemia Causes
• Re-feeding syndrome
• Respiratory alkalosis
• Alcohol abuse
• Malabsorption

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Phosphorus

• Hypophosphatemia
• Clinical presentation
• Muscle dysfunction and weakness diploplia, low
  CO, dysphagia, respiratory depression
• AMS
• WBC dysfunction
• Instability of cell membrane ? rhabdomyolysis
• Treatments
• supplementation