12. Electrolyte Emergencies

sodium normal value

135-145

chloride normal value

96-106

potassium normal value

3.5-5.5

calcium normal value

8.5-10.5

Mg normal value

1.7-3.5

phosphorus normal value

2.5-4.5

bicarb normal value

22-26

what is this?

hypernatremia

HCO3 and pCO2 normal values

general hypernatremia tx

dextrose in water: Correction goal: Na 5mEq/L adjustment per day

• correcting too quickly can lead to cerebral edema

normal saline (titrate based on target Na correction)

Neurogenic Diabetes Insipidus tx

Desmopressin

Nephrogenic Diabetes Insipidus tx

• remove offending agent

• Thiazide diuretics (Hydrochlorothiazide)

• Nonsteroidal Anti-inflammatory Drug (Indomethacin)

• if lithium accquired DI → Potassium sparing diuretic (Amiloride)

hypernatremia dispo

all admitted

what is this?

hyponatremia

Hypotonic hypovolemic hyponatremia tx

Normal Saline (0.9%)

Correct 5mEq/L adjustment per day

Hypotonic hypervolemic hyponatremia tx

if CHF → loop diuretic (furosemide)

if cirrhosis → albumin infusion + hypertonic saline

Hypotonic Euvolemic hyponatremia tx

if SiADH → fluid restriction + free water diuresis (oral urea, furosemide w/ salt tablets, vaptrans)

if hypothyroidism → levothyroxine

if adrenal insufficiency → hydrocortisone

consequence of overcorrection of hyponatremia

osmotic demyelination syndrome

who gets admitted with hyponatremia

symptomatic or Na < 125

Hypochloremia tx

NS fluids

what is this?

hyperkalemia

what are the ECG changes in hyperkalemia

6.5 - 7.5 mEq/L: peaked T waves, prolonged PR interval, shortened QT interval

7.5 - 8.0 mEq/L: widened QRS interval, flattened P waves

10 - 12 mEq/L: sine wave, ventricular fibrillation, heart block

hyperkalemia tx

1. stabilize cardiac membrane (pick 1)

• indicated if ECG changes of K>7

• Calcium Gluconate IV

• Calcium Chloride IV

2. shift potassium intracellularly (pick 1)

• Insulin + Dextrose

• Nebulized Albuterol

• Sodium Bicarbonate (if pt acidotic w/ pH <7.1)

3. remove potassium from body

• furosemide (Lasix)

• Gastrointestinal potassium binders: Sodium Zirconium cyclosilicate (Lokelma) or Patiromer (Veltassa)

• Hemodialysis is definitive treatment

hyperkalemia dispo

admit if K > 6

what is this

hypokalemia

ECG findings in hypokalemia

U waves, QT prolongation

hypokalemia tx

potassium repletion

• PO KCl tablets if K > 2.5

• IV KCl if K > 2.5

magensium repletion

who gets admitted with hypokalemia?

K < 3.0 w/ ECG changes

what meds can cause hypercalcemia?

lithium, thiazide diuretics, excessive vit D

what are sx of hypercalcemia?

hypercalcemia management

Asymptomatic Ca < 12mg/dL → no immediate tx

Symptomatic Hypercalcemia > 12 mg/dL

• dilute w/ isotonic NS

• calcitonin if Ca>14

• Bisphosphonates (Pamidronate, Zoledronate) if Ca>14 + no renal insufficiency

dialysis for severe cases

steroids if decreased GI absorption

who gets admitted with hypercalcemia

symptomatic or Ca >13

what is this?

hypocalcemia

ECG findings related to Ca

hypercalcemia = QT shortening

hypocalcemia = QT prolongation

hypocalcemia tx

asymptomatic

• calcium gluconate

• vit D (calcitriol)

symptomatic

• replace Ca: IV calcium gluconate or calcium chloride

• address other electrolyte abnormalities

• Avoid phenothiazine antipsychotics

• Avoid furosemide diuretics

who gets admitted w/ hypocalcemia?

Symptomatic patients

Ionized Ca < 3.2 mg/dL

presentation of hypermagnesium

hypermagnesium tx

dilute Mg: isotonic saline (NS)

flush out Mg: furosemide IV

cardiac stabilization: IV calcium gluconate or chloride

hemodialysis if Mg > 8

clinical presentation of hypomagnesium

hypomagnesium tx

serum > 1.7 → no tx

serum < 1.7

• asymptomatic → Mg Oxide PO

• symptomatic → MgSO4 IV over 1 hr

serum < 1.2 → MgSO4 IV over 2 hrs

torsades de pointes → MgSO4 over 2min

hyperphosphatemia clinical features

increased activity, dyspnea, anorexia, n/v, insomnia

hyperphosphatemia

dilute w/ isotonic saline NS IV

diuresis w/ acetazolamide IV

phosphate binder → aluminum hydroxide

if refractory to initial thearpies → hemodialysis

hypophosphatemia clinical presentation

hypophosphatemia tx

mild-to-moderate >2 → Kphos or neutra phos PO

moderate, unable to take PO or <2 → Kphos IV (central line)

severe <1 → Kphos or Naphos IV

metabolic acidosis

low pH, low bicarb

excess H+ (from sepsis, renal faliure, DKA, rhabdo) → bicarb HCO3 low

compensation = tachypnea → CO2 low

metabolic alkalosis

high pH, high bicarb

loss of H (vomiting or diuretics) → bicarb high

compensation = bradypnea (trying to hold on to CO2) → CO2 increases

respiratory acidosis

low pH, high CO2

increased CO2 (from hypoventilation)

compensation = bicarb generation to try and balance

respiratory alkalosis

high pH, low CO2

low CO2 (hyperventilation)

compensation = bicarb excretion → levels are low