The Glomerulus Flashcards
What does it mean when a patient is euvolemic?
They are in fluid balance
What is glomerular filtration rate?
The amount of filtrate that is produced from the blood flow per unit time
Define osmolality
Amount of solute per kg of solvent
Define osmolarity
Number of osmoses of solute per litre of solvent
osmolaRity - litRe
What is renal blood flow?
Give an approx value
Volume of blood delivered to the kidney
~1L/min
What is the approx renal plasma flow?
~600ml/min
How do you calculate the renal plasma flow?
RPF = renal blood flow x (1-haematocrit)
What is haematocrit?
Blood made of RBCs
~40-45%
What is the approx value of the GFR?
~125ml/min
How do you calculate the filtration fraction?
FF = GFR/RPF
GFR - glomerular filtration rate
RBF - renal plasma flow
What does the filtration fraction tell you and what is its approx value?
Proportion of blood that has been filtered
~20%
Why do proteins not enter the Bowman’s capsule?
- too large to fit through the small fenestrations + podocytes
- foot processes on podocytes are negatively charged and repel negatively charged proteins e.g. albumin
What percentage of blood from renal artery is filtered at one time?
20%
