Fluid Compartments And Solutes Flashcards
Intracellular vs Extracellular
Higher pH in plasma
Osmolarity is the same 285
What are cation and anion levels like intracellular and extracellular
Extracellular: sodium ions most plentiful and organic phosphate
Intracellular:potassiumions and proteins
Osmole
The number of moles of a solute that contributes to the osmotic pressure of the solution
Double nacl as there are two ions
Glucose stays same
Membrane permeable to both water and solute
No net volume change
- What happens if a membrane is permeable to H2O and solute A but not B?
Cell swells
Permeable to water but not a solute
Cell swollen and may rupture
Tonicity
The strength of a solution as it affects the final cell volume
Depends on cell membrane permeability and solution composition
Why don’t cells burst if the conc of impermeant solutes (proteins) is much higher in them than in interstitial fluid/plasma?
Because Na+K+ ATPase maintains the concentration of Na+ ions much lower inside than outside the cell
It makes the membrane Imperi led to na+ as it is pumped out if it enter
Tissue preservation
Donated organs perfumed with cold solutions via arterial supply to reduce deterioration in hypothermia
Sodium potassium atpase stops functioning below 15 degrees as there is no oxygen thus sodium ions can enter with chloride ions causing cell to swell and die
University of Wisconsin solution
Reduced hypothermic cell swelling and enhances preservation of donated organs
Lack of sodium and chloride ions,presence of extracellular impermeant solutes and presence of macro molecular colloid eg strach reduce swelling
Allopurinol and gluthathione
Act as antioxidants
The balance of which 2 pressures determines solute and fluid movement across a vessel wall?
- Colloid osmotic pressure (COP)/oncotic pressure generated by higher concs of plasma proteins in the capillary than outside
- Hydrostatic pressure inside the vessel caused by the flow of blood through the vessel which is greater than that in the tissues around it leading to a tendency to push molecules through capillary pores
Normally hydrostatic pressure is slightly greater causing net leakage from capillaries
Oedema
Accumulation of fluids within tissues reuksting in imbalance during normal cycle curing accumulation in interstitial space
Plasma leakage»capacity of lymphatics to collect and return in circulation this occurs
How does lymph fluid return to circulation
Via lymphatic ducts in the subclavian region or via lymph nodes
Inflammation
Oedema is a sign of inflammation
