FRACTURED FEMUR

Question 1

Describe the 3 stages of haemostasis

Answer 1

vascular spasm
- due to smooth muscle contraction in arteriole walls reducing blood through injured vessels to assist with platlet plug formation so coagulation can occur

platelet plug formation

• platelet adhesion and aggregation
• chemical released bring more platelets to the are and promote vascular spasm

coagulation

• platelet plug is reinforced with fibrin threds to form a mesh
• mesh traps blood cells and sels hole until repaired

Question 2

Name the 2 hormones which act on the kidney to help restore blood volum e

Answer 2

Aldosterone INCREASES tubular reabsorption of NA+, water FOLLOWS by osmosis. INCREASING blood plasma volume

Anti diuretic DECREASES water lost from the collecting duct so INCREASES blood plasma volume

Question 3

Explain 2 mechanisms related to blood vessels that increase BP

Answer 3

• constriction of arterioles to INCREASES pvr which INCREASES bp
• Constriction of veins to INCREASE venous return . increases venous return will INCREASE preload therefore increases BP

Question 4

Define haematocrit and why it is lower than normal

Answer 4

the percentage of blood occupied by the red cells. her blood volume would have been restored by intravenous saline therefore diluting it. so her haematocrit would be lower

Question 5

Name and describe the stage of bon healing occuring for june

Answer 5

formation of fracture haemotoma

• blood leaks from damaged vessel and forms clot
• nearby bone cells die due to lack of nutrients to tissues at site of fracture
• phagocytosis and osteoclasts remove dead and damaged tissue

Question 6

name the main mineral in maintaing bone tissue

Answer 6

calcium

Question 7

name and describe the hormone that enables increased deposits of this mineral

Answer 7

calcitonin

- stimulates deposits of clalcium in bone tissue by inhibiting osteoclast activity