Hyperaemia Flashcards
What is colloid osmotic pressure the same as?
Oncotic pressure
What is hyperaemia?
Accumulation of RBCs inside blood vessels
Can be physiological or pathological
Hyperaemia can be active or passive. What are these also known as? Do they take place in arteries or veins?
Active hyperaemia = inflammation. Accumulation of arterial blood in arteries, arterioles and arteriolar capillary bed
Passive hyperaemia = congestion. Accumulation of blood in veins and venular capillary bed
Is active hyperaemia local or generalised? Is it acute or chronic? What about passive hyperaemia?
Active - local, acute
Passive - local or generalised, acute or chronic
What colour are the tissues affected by active hyperaemia and passive hyperaemia
Active - bright red
Passive - dark red/blue and swollen
What is ischaemia? What are the different types?
Inadequate blood supply to a tissue or organ
Can be complete or partial
Can be local or general
What causes ischaemia? (3 ways)
Heart failure (general ischaemia) Obstruction of an artery (local) Venous obstruction (local)
What is obstruction of artery/arteriole related ischaemia associated with?
Idiopathic cardiac hypertrophy
Venous obstruction causes stagnation, hypoxia and ischaemia. What is stagnation?
No blood flow/movement
Local passive hyperaemia is an increase in RBCs due to obstruction of venous return from an organ. What can cause this?
Organ misalignment
Venous thrombosis or embolism
Compression of vessel
What are the different types of organ misalignment?
Intussusception (invagination) Volvulus Torsion Twist Herniation with strangulation
How does organ misalignment cause necrosis and haemorrhagic infarction?
Veins occluded
Persistence of arterial blood supply
Increased blood pressure and congestion
Blood extravasation
What is infarction?
Tissue death to inadequate blood supply (ischaemia leads to infarction)
What is intussusception or invagination? Where is this most likely to occur?
Trapping of mesentery and vessels causes intestine to fold into the section ahead of it
Small intestine
What is volvulus?
Loop of intestine twists 180 degrees around its axis
or 360 degrees if gastric volvulus