PSL201: lecture one
Case Study: Marathon runner
– A37 year old woman completed her fourth marathon in 4HRs and 35MINs.
+ She was taken to the emergency room 6HRs later because she was suffering from mental confusion
+ Her initial serum [Na+] was 121 mmol/L
- (Normal serum [Na+] = 137-145 mmol/L)
1. What could be the cause of her low serum [Na+] value?
- She drank too much water before the marathon
2. Why is she suffering from mental confusion?
- Her brain swelled
3. How would you treat her?
– The total body water has 42L of volume... 60% of body weight
- exclusion (no water): lumen of the gut, tubules of the nephron, air part of the lungs
– Intercellular fluid
+ water inside the cell, in the tissues.
+ water found in blood vessels and cell membrane
– Extracellular fluid
+ the fluid outside of the cells tissue