Pharmacology-IV Fluids Flashcards
What is the difference between dehydration and hypovolemia?
Dehydration = water loss alone. Hypovolemia = volume depletion
What is PVE?
Plasma volume expansion = Volume of infused fluid/volume of distribution
What is the main factor in the vasculature that allows fluid to accumulate in the third spaces?
EGL (endothelial glycocalyx layer). The endothelia are the main players in determining what fluid goes to what compartments in the body.
What are your options for fluid replacement? Which is theoretically better for dehydration? Which is better for patients with ascites? Which is better for hypvolemia?
Colloid, 0.9% saline, or 5% dextrose. 5% dextrose is better for dehydration if you have high sodium levels already. 0.9% saline is good for hypovolemia. 5% albumin is good for ascites.
Why do you care if you are going to give an IV to someone in septic shock?
Their endothelia are highly permeable and you need to think about how much fluid you’re going to give. Note that in a healthy person, infusing 1L of 0.9% saline will distribute as seen below.
How is volume distributed in a 70kg male?
*
What IV solution would you consider giving a patient who is acidotic?
Combination therapy with lactate instead of chloride. The lactate will be taken to the liver and metabolized into bicarbonate which has a hydrogen sparing effect.
What complications exist for normal saline infusions?
Hyperchloremia = vasoconstriction and reduced GFR. Acidosis = clotting problems.
A patient comes to see you in shock and needs IV fluids. How might you change the amount of fluid from when he first comes in to when he is in recovery?
At first you can give a lot of fluids to keep him from going into hypovolemic shock. Once he is stable you need to taper it off to prevent acute kidney injury from fluid overload.
A 25 year old male comes in with massive hematemesis. He has a history of peptic ulcer. What kind of fluid resuscitation would you initially prescribe while you wait for blood infusion? What would you expect his hematocrit to be after infusion?
Normal saline. This will keep his volume up short term until blood comes. His hematocrit will be low because you are diluting his blood.
An 18 year old male returns from the Caribbean with severe diarrhea and vomiting for the past 48 hours. He has metabolic acidosis, low [K+] and a blood pressure of 80/70. What fluid will you prescribe?
He needs something to help his blood become more basic so you give him lactated ringers. You would also give him some more K+.
A 40 year old alcoholic comes to see you with end-stage liver disease. He has ascites. What fluid will you prescribe?
Colloid (albumin) to pull fluid out of the interstitial space.
