Quiz 7 Flashcards
What is capillary filtration?
net movement of water from the capillary to the interstitial space
(net driving force > 0)
What is capillary reabsorption?
net movement of water from the interstitial space to the capillary
(net driving force < 0)
What are the Starling Forces with regards to capillary filtration/reabsorption? (4)
- Capillary hydrostatic pressure (P.c)
- Interstitial fluid hydrostatic pressure (P.if)
- plasma colloid osmotic pressure (Pie.p)
- interstitial fluid osmotic pressure (Pie.if)
When water moves from a region of high concentration to one that has a lower concentration of water
Osmosis
If Net Driving Forces are positive, does it favor capillary filtration or reabsorption?
Filtration
Are hydrostatic pressures within the capillary equal at the arteriolar end and the venous end?
No, pressures higher on arteriole side
Under normal circumstances, what Net Driving Force favors fluid movement INTO the capillary?
plasma colloid osmotic pressure a.k.a. plasma oncotic pressure (reabsorption)
What would the Net Driving Forces be in a patient with congestive heart failure? Would they favor filtration or reabsorption?
increased capillary hydrostatic pressures - they would increase NDF
Filtration
What is the function of the lymphatic system? and what does it return to circulation? (4)
an accessory route through which fluid can flow from the interstitial spaces into the blood
Returns to circulation:
- Protein (Albumin)
- Bacteria
- Fat
- Excess fluid
How is plasma filtrate returned to the circulation by the lymphatic system? (4)
- Lymphatic vessel contraction
- Intermittent skeletal muscle activity
- System of one-way valves
- Tissue pressure
What is the thoracic duct? Where is it found and what does it connect to?
Main vessel of lymphatic system (can generate 50-100mmHg pressure)
Abdomen up to Left chest/neck
Drains to Left IJ, and Left Subclavian
What things may cause edema? (4)
- Increased capillary hydrostatic pressure
- Decreased plasma oncotic pressure (decrease in plasma protein)
- Increased capillary permeability
- Lymphatic obstruction
Filtration, the movement of fluid out of the capillaries, is driven by the?
Capillary hydrostatic pressure
Mechanisms of Exchange Across The Capillary Endothelium (4)
- Vesicular transport - proteins
- Active transport - glucose
- Diffusion - Gases
- Bulk flow (via intracellular clefts/pores) - Water, Electrolytes
Changes in _____ pressure have a much higher quantitative influence on capillary pressure than do similar changes in ______ pressure
- Venous
- Arterial
Net capillary fluid filtration is enhanced by?
Decreased capillary plasma oncotic pressure
interstitial volume depends on? (4)
- Rates of filtration
- reabsorption
- lymph flow
- compliance of interstitial compartment
which of the two oncotic pressures have a greater force?
capillary plasma oncotic pressure (forcing reabsorption)
what does the increased concentration of protein along the capillary do? (2)
- increases capillary plasma oncotic pressure
- Decreases NDF (net driving force)
Effect causing extra force in plasma protein?
Gibbs-Donnan Effect - cations in plasma creating extra pressure (9mmHg)
on which sides does filtration/reabsorption occur?
Fitration - Arteriole side
Absorption - Venule side
Capillary hydrostatic pressure (P.c) in Arterioles vs Venules? and net driving forces?
30mmHg vs 10mmHg
15mmHg vs (-)5mmHg
What does a decreased capillary hydrostatic pressure and increased oncotic pressure reveal?
Dehydration
Lower NDF and longer Reabsorption period