Question
A 7-year-old boy punctures his thumb with a rusty nail. Four hours later, the thumb appears red and swollen. Initial swelling of the boy’s thumb is primarily due to which of the following mechanisms?
| A. |
Decreased intravascular hydrostatic pressure
|
| B. |
Decreased intravascular oncotic pressure
|
| C. |
Increased capillary permeability
|
| D. |
Increased intravascular oncotic pressure
|
Show Answer
|
Correct Answer � C
Explanation
|
|
Answer :C Increased capillary permeability
Forces that regulate the balance of vascular and tissue fluids include
(1)hydrostatic pressure
(2) oncotic pressure
(3) osmotic pressure,
(4) lymph flow.
-
During inflammation, an increase in the permeability of the endothelial cell barrier results in local edema.
-
Vasodilation of arterioles exacerbates fluid leakage, and vasoconstriction of postcapillary venules increases the hydrostatic pressure in the capillary bed potentiating the formation of edema.
-
Vasodilation of venules decreases capillary hydrostatic pressure and inhibits the movement of fluid into the extravascular spaces.
-
Acute inflammation is not associated with changes in plasma oncotic pressure
Like this:
Like Loading...
