Drugs for Hypo/Hypernatremia Flashcards
“-volemia” refers to what measurement?
Na+ CONTENT
Edema refers to what measurement?
Na+ CONTENT
Na+ content is described how?
“-volemia”
“-natremia” refers to what measurement?
Na+ concentration which is determined by the WATER amount
What determines the Na+ concentration?
Water amount
Na+ content does not equal Na+ concentration. Where are each measured and what system effects them?
Na+ content - ECF; RAAS system
Na+ concentration - Plasma; ADH
This refers to the effect of a solution on the volume of the cell
Tonicity
What happens to the cell with a hypotonic solution?
Cell swells
What happens to the cell with a hypertonic solution?
Cell shrinks
0.9% NaCl is?
Isotonic saline
Effect of Isotonic Saline (nacl)?
Increased ECF volume
Effect of Hypotonic Saline (0.45% nacl)?
Both ECF and ICF increase
Effect of Hypertonic Saline (3-5% nacl)?
Increased ECF and decreased ICF
Effect of Albumin?
Plasma volume increases
Effect of 5% dextrose?
Increased total body water
The body fluid volume and concentration must remain relatively constant. What ensures that happens?
Water and solutes are excreted separately
Body Na+ content issues are reflected with hypo/hypervolemic ECF. What are the signs of Hypovolemic ECF?
- Decreased skin turgor, thirst and dry mucous membranes
- Oliguria
- Increased HR and decreased BP
Body Na+ content issues are reflected with hypo/hypervolemic ECF. What are the signs of Hypervolemic ECF?
Weight gain and edema
- Bounding pulses
What defines Hypernatremia?
Plasma [Na+] > 145
What defines Hyponatremia?
Plasma [Na+] < 135
Hypernatremia and Hyponatremia mean that there is a ____ problem
Water problem
What are the symptoms for Hyponatremia?
SALT LOSS
- Stupor/coma
- Anorexia (N/V)
- Lethargy
- Tendon reflexes decreased
- Limp
- Orthostatic hypotension
- Seizures
- Stomach cramp
What are the symptoms for Hyponatremia?
SALT LOSS
- Stupor/coma
- Anorexia (N/V)
- Lethargy
- Tendon reflexes decreased
- Limp
- Orthostatic hypotension
- Seizures
- Stomach cramp
This class of drugs causes more solute loss than water loss
Diuretics
This class of drugs causes more water loss than solute loss
Vaptans
To treat Hyponatremia, what is the treatment for no or minimal symptoms?
Fluid restriction
To treat Hyponatremia with moderate symptoms, what is the treatment?
Vaptans or Hypertonic NaCl
To treat Hyponatremia, what is the treatment for severe symptoms?
Hypertonic NaCl
When treating severe Hyponatremia with Hypertonic NaCl, if it is infused/corrected too fast, what side effect can occur?
Osmotic demyelination syndrome
Vaptans can treat Hyponatremia. What is their MOA?
(-) ADH-regulated water reabsorption to promote excretion of free water
Where do Vaptans work?
Collecting duct
What are the 2 Vaptans for Hyponatremia?
Conivaptan
Tolvaptan
How is Conivaptan given and what receptor does it work at?
IV
– affinity to block both receptor types (V1A and V2)
How is Tolvaptan given and what receptor does it work at?
Orally in the hospital setting
– Selective V2 receptor antagonist
Why must Tolvaptan be used for LESS than 30 days?
Chronic use can cause hepatotoxicity
Besides Hyponatremia, what else is Tolvaptan used for?
Slows the progression of adult polycystic kidney disease
What are some possible side effects of the Vaptans?
Orthostatic hypotension
Fatigue and thirst
Polyuria/bedwetting
What are the symptoms of Hypernatremia?
TRIP
- Tremors/twitching
- Restlessness
- Intense thirst
- Pulmonary and peripheral edema
What are the symptoms of Hypernatremia?
TRIP
- Twitching/tremors
- Restlessness
- Intense thirst
- Pulmonary and peripheral edema
If a patient has Hypernatremia and hypovolemia, what type of saline should be given?
Isotonic
If a patient has Hypernatremia and they are NOT hypovolemic, what type of saline should be given?
Hypotonic
What is a drug to treat Hypernatremia?
Desmopressin (DDAVP)
What is a drug to treat Hypernatremia?
Desmopressin (DDAVP)
MOA for Demopressin?
V2 agonist (ADH analog) which increases water reabsorption
With what conditions is Desmopressin used?
Central diabetes insipidus
Primary nocturnal enuresis
What is a possible adverse effect of Desmopressin?
Hyponatremia
What is a possible adverse effect with Desmopressin?
Hyponatremia
Desmopressin can treat Hypernatremia. What is its MOA?
ADH analog that is a V2 agonist ==> increases water reabsorption
