Lecture 48 - Hyponatremia

Question 1

4 processes which may be abnormal leading to hyponatremia

Answer 1

GFR

Distal Delivery

Thick Ascending Limb reabsrobtion of NaCl

Suppression of ADH

Question 2

Conditions/states which may lead to a hypovolemic hyponatremia

Answer 2

Diuretics,
Diarrhea/Vomiting
Salt Losing Nephropathy

Question 3

Conditions/states which may lead to a euvolemic hyponatremia

Answer 3

SIADH,

Reset Osmostat

Hypothyroid disease

Psychogenic H20 Ingestion

Drugs that increase ADH

Question 4

Conditions/states which may lead to a hypervolemic hyponatremia

Answer 4

CHF, Cirrhosis, Nephrosis

Question 5

Signs of Hyponatremia

what is the threshold for obtundation

Answer 5

bnormal sensorium , depressed DTRs, Cheyne Stokes respiration, hypothermia, pathological reflexes, pseudobulbar palsy, Seizures; can even lead to herniation and death

obtundation = < 125

…sz…

<115 … coma, respiratory arrest

Question 6

Symptoms of Hyponatremia

Answer 6

Symptoms – Lethargy, apathy, disorientation, muscle cramps, anorexia and nausea, agitation

Question 7

Treatment for Chronic hyponatremia

Answer 7

don’t necessarily treat bc the brain can readjust and compensate

Question 8

Treatment for acute hypovolemic hyponatremia

Answer 8

Saline; restore the blood volume

Question 9

Treatment for acute euvolemic hyponatremia

Answer 9

water restriction and/or Vasopressin Receptor (V2) Antagonists (block water resorption)

Question 10

Treatment for acute hypervolemic hyponatremia

Answer 10

Water restriction, Diuretics; V2 receptor antagonists

Question 11

Symptoms of Hypervolemia

Answer 11

Elevated JVP
no orthostatic symptoms
Edema – anasarca, CHF, rales, Crackes, Ascities, Hepatomegaly

Question 12

Symptoms of Hypovolemia

Answer 12

Low/Normal JVP
Orthostatic symptoms
No edema of fluid overload
Poor skin turgor

Question 13

what is the calculation for Posm

Answer 13

Posm = 2 Na + Gl/18 + BUN/2.8

Question 14

Euvolemic Hypotonic Hyponatremia DDX

Answer 14

SIADH
Psychogenic H20 Ingestion
Hypothyroidism
Drugs

Question 15

HyperVolemic Hypotonic Hyponatremia DDX

Answer 15

CHF
Cirrhosis
Nephrotic Syndrome

Question 16

Non Renal DDx of Hypovolemic, Hypotonic Hyponatremia

how did you know if was non renal losses of Na?

Answer 16

Vomiting, Diarrhea, Fistula
Skin Losses

bc UNa < 20

Question 17

Renal DDx of Hypovolemic, Hypotonic Hyponatremia

Answer 17

Diuretic Use
Salt Wasting Nephropathy
Adrenal Insufficiency (Addison’s)
Osmotic DIuretics

Question 18

Hyponatremic Patients; what diagnostic clue specific for adrenal Insuffieciency? why?

Answer 18

Hyperkalemia in the setting of hyponatremia = Adrenal Insuffiency –

Decreased Mineralcorticoid stimulation = decreased K secretion;