SODIUM

Question 1

Isotonic Hyponatremia (Pseudohyponatremia)

Answer 1

275-290 mOsm/L
high levels of lipids and proteins that lead to a dilation effect where sodium appears low because of the high levels of triglycerides and protein

Question 2

Hypertonic Hyponaterima

Answer 2

(>290 mOsm/L)
Common with elevated blood sugar values

Question 3

Normal Sodium levels

Answer 3

135-145 mEq/L

Question 4

Serum Osmolality Calculation

Answer 4

Osm = (2 x NA) +(BUN/2.8) + (Glucose/18)

Question 5

HYPOvolemic HYPOtonic HYPOnatremia

Answer 5

Losing sodium and water, decreased TBW
- Renal causes (Urine Na is greater than 20) : Diuretics, Adrenal Insufficiency, Salt losing nephropathy, Cerebral salt wasting
- non-renal causes (urine Na is less than 20) : blood loss/hemorrhage, skin loss, GI loss
Treatment:
If patient presents symptoms: 3% NaCl
If patient is not showing symptoms: Normal Saline

Question 6

Hypervolemic Hypotonic Hyponatremia

Answer 6

Increased TBW, increased sodium which holds onto fluid leading to edema
Treatment :
If Patient is symptomatic: Furosemide and 3% NaCl
If No symptoms present: furosemide

Question 7

Acute symptoms of Hyponatremia

Answer 7

Altered mental status, seizures, cerebral edema, increased intracranial pressure, Brain herniation

Question 8

Hypernatremia

Answer 8

results of loss of water or hypotonic fluids or ingestion of sodium or hypertonic fluids

Question 9

Isovolumic Hypernatremia

Answer 9

Decreased TBW, normal sodium –> loss of water
Causes:
Diabetes insipidus, skin loss, lactogenic, osmotic diureses
Treatment:
Desmopressin
Vasopressin

Question 10

Hypervolemic Hypernatremia

Answer 10

Increased TBW, very increased sodium
causes:
Sodium overload
Treatment
-stop hypertonic fluid, diuretic if needed

Question 11

Hypovolemic Hypernatremia

Answer 11

Decreased TBW, Decreased sodium –> loss of water and sodium
Causes:
renal, GI, adrenal, Lung, Skin
Treatment
Restore with normal saline
D5W infusion

Question 12

ISOvolemic HYPOtonic HYPOnatremia

Answer 12

increased TBW, Normal or slightly higher total body Na
Causes:
adrenal insufficiency
Hypothyroidism
Psychogenic polydipsia
SIADH
Treatment
Furosemide and 3% NaCl if symptomatic
if asymptomatic - NS and water restriction

Question 13

SIADH

Answer 13

SYNDROME OF INAPPROPRIATE ANTIDIURETIC HORMONE RELEASE

Causes: tumors, CNS disorders, DRUS ( NSAIDS, SSRIs, TCAs)
Treatment
free H2O restriction
Vaptans (conivaptan, Tolvaptan)

Question 14

Signs of Chronic Hyponatremia

Answer 14

Brain cells extrude solutes
minimal brain swelling
Death is rare

Question 15

Treament of acute symptomatic Hyponatremia

Answer 15

Maximum increase of 8-12 mEq/L in the first 24hrs