Ischemia

Question 1

What is ischemia?

Answer 1

Local insufficient blood supply due to insufficient flow or obstruction of arterial blood.

Question 2

What affects the sensitivity of the organ to ischemia?

Answer 2

Organ type and its sensitivity to oxygen deficiency

Question 3

Three types of ischemias

Answer 3

General ischemia
Local ischemia
Collateral ischemia

Question 4

What causes general ischemia?

Answer 4

-Decrease in amount of blood (hypovolemia)
-Decrease in RBC or hemoglobin (anemia)

Question 5

Three types of local ischemia and what causes them?

Answer 5

-Angiospastic/refractory ischemia: vasoconstriction (e.g. due to adrenalin)
-Obstructive ischemia: thrombus or embolus in arterial lumen (can cause infarction if sudden)
-Compression ischemia: external pressure to artery (tumor, exudate)

Question 6

What can cause collateral ischemia?

Answer 6

Usually happens in brain and other organs with massive blood supply.

Happens if there is a sudden drop in blood pressure (e.g. due to removal of rumen tympany).