CLASS 5 - FLUID + ELECTROLYTES (Na, K, Albumin), DIURETICS + RELATED THERAPIES Flashcards
What is homeostasis?
Maintenance of a constant internal environment despite changes in the external environment.
It is important than Na is ____ in plasma but ____ in cells and than K is ____ in plasma and ____ in the cell
Na: high in plasma, low in cells
K: low in plasma, high in cells
Why is protein considered to be more important for OP balance than glucose?
B/c glucose changes fast which protein is more stable.
What is the normal blood plasma value for Na?
K?
Albumin?
Na - 125-145 mmol/L
K - 3.5 - 5 mmol / L
Albumin - 35-50 g / L
Define the following:
- Hypernatremia
- Hyponatremia
- Hyperalbuminemia
- Hypoalbuminemia
- Hypervolemia
- Hypovolemia
- Hypernatremia: high sodium levels in the blood
- Hyponatremia: low sodium levels in the blood
- Hyperalbuminemia: high albumin levels in the blood
- Hypoalbuminemia: low albumin levels in the blood
- Hypervolemia: volume excess
- Hypovolemia: volume defecit
what is osmolality? what is normal osmolality?
measure of the osmotic force of solutes in the plasma (done by a blood test)
280-300 mmol / kg
What is osmotic pressure?
What are the main particles that determine plasma osmotic pressure?
Force that pulls / keeps fluids in the plasma.
Na, protein, and glucose.
What is hydrostatic pressure?
What does a high hydrostatic pressure indicate?
Where is hydrostatic pressure higher in the capillary bed: arterial end or venous end?
Force of pressure pushing fluid against the vessel wall.
High hydrostatic pressure indicates that the fluid is more likely to move out of the vessel.
Higher at the arterial end of the capillary.
What is oncotic pressure?
What is the main protein that determines plasma oncotic pressure?
Oncotic pressure = osmotic pressure of proteins
Albumin
What is fluid spacing?
fluid mvmt between ECF and ICF
Fluid spacing:
What does first spacing indicate?
What does second spacing indicate?
What does third spacing indicate?
first spacing indicates a normal fluid balance.
second spaacing indicates edema in tissues.
third spacing indicates that fluid is accumulating in body spaces such as ascites, blisters, pleural effusion (buildup of water outside of the lungs in the pleural space).
do volume imbalances always have Na imbalances?
yes.
What role does the Hypothalamus-Pituitary Gland in the brain play in the regulation of water?
Hypothalamic osmoreceptors sense the increased osmolality (meaning there are too many particles and not enough fluid); triggers thirst; ADH is released from pituitary gland which facilitates free water absorption (not Na) therefore diluting existing NA in the blood.
What role does the adrenal gland (on top of the kidney) play in the regulation of water?
RAAS (Renin Angiotensin Aldosterone System)
look at diagram in notes
Describe the renal regulation of water
- adjusts urine volume
look at diagram in notes
What is insensible water loss?
- water loss from breathing and insensible perspiration (water only)
- excessive sweating
- water used in metabolic preocesses
What is the main determinant of IVF/IF osmolality?
Na
What are the 2 main hormones that aid in the regulation of Na and ECF balances? What are their fucntions?
main hormone: ADH (keep water)
secondary: Aldosterone (keep Na and water)
What does a Hypertonic IVF/IF (high Na : low water) have on the cell?
water moves out of the cell into the ECF to dilute the concentration which results in cell shrinkage.
What does a Hypotonic IVF / IF (low Na: high water) have on the cell?
causes water to move into the cell which results in cell swelling and hemolysis.
How does BP change with hypervolemia + hypovolemia?
Hypervolemia = increased BP Hypovolemia = decreased BP, postural hypotension
How does pulse rate change with a decreased and elevated BP?
- When BP drops (hypovolemia) –> HR increases to compensate
- When BP is elevated (hypervolemia) –> HR may lower
How does pulse strength change with hyper and hypovolemia?
hypovolemia –> weak, thready pulse (+1)
hypervolemia –> bounding pulse (+3)
What could result from hypovolemia and decreased BP?
Peripheral vasoconstriction (blood will move to central body and organs) which will result in pallor, cool skin, and decreased capillary refill
How does the visibility of jugular veins change with hyper and hypovolemia?
- Hypervolemia = veins engorged + distended
- Hypovolemia = flat, non-visible
what are some respiratory changes associated w volume changes?
- pleural effusion
- pulm edema
- pulm congestion
- SOB, irritative cough, frothy pink sputum, crackles on auscultation
- increased resp rate due to decreased tisue perfusion
What effect does increased water volume w hyponatremia have on the brain?
What effect does decreased water volume w hyponatremia have on the brain?
increased water volume = swelling –> confusion
decreased water volume = shrinkage –> confusion, seizures
–> profound depletion may cause an alteration in sensorium due to reduced cerebral tissue perfusion
What are the effects of mild + severe fluid deficits on the skin?
decreased turgor (tenting) and mobility
mild defecits: skin appears, warm, dry, wrinkled, and non-elastic.
severe defecits: cool and pale if there is vasocon.
What are the effects of excess fluid on the skin?
Edema
skin may feel cool related to fluid accumulation and a decrease in blood flow secondary to the pressure of the fluid.
Fluid can stretch the skin and cause it to feel tight and hard.
How can we protect patients with edema from skin breakdown? How can we help promote venous return and fluid reabsorption?
- Protect the edematous tissues from heat and cold, prolonged pressure, and trauma.
- Elevation of edematous extremities can help promote venous return and fluid reabsorption
What is the effect of free (tap) water on plasma Na?
Tap water has no significant Na. Will provide water to dilute plasma Na.
What are diuretics?
Diuretics are drugs that adjust the volume and / or composition of body fluids.
What is the MOA of most diuretics?
Most block Na reabsorption in the nephron
What is a common side effect of diuretics?
Hypovolemia and hypertension.
where is most of the potassium in the body located? how much is in the plasma?
In the cells
plasma: 3.5-5 mmol / L
What are the clinical manifestations of Hyperkalemia?
- Fatal tachycardias
- confusion
- anxiety
- dyspnea
- weakness
- heaviness of the lungs
- numbness or tingling of hands, feet, and lips
What are the clinical manifestations of hypokalemia?
Weakness or paralysis of skel muscle
irreg heart beat
decreased intestinal function
Why is potassium chloride not given by IV push?
rapid infusion results in cardiac arrest
What is the effect of free (tap) water on plasma Na?
Tap water has no significant Na. Will provide water to dilute plasma Na.
What are diuretics?
Diuretics are drugs that adjust the volume and / or composition of body fluids.
What is the MOA of most diuretics?
Most block Na reabsorption in the nephron
What is a common side effect of diuretics?
Hypovolemia and hypertension.
where is most of the potassium in the body located? how much is in the plasma?
In the cells
plasma: 3.5-5 mmol / L
What are the clinical manifestations of Hyperkalemia?
- Fatal tachycardias
- confusion
- anxiety
- dyspnea
- weakness
- heaviness of the lungs
- numbness or tingling of hands, feet, and lips
What are the clinical manifestations of hypokalemia?
Weakness or paralysis of skel muscle
irreg heart beat
decreased intestinal function
Why is potassium chloride not given by IV push?
rapid infusion results in cardiac arrest
