Patho Week 5

Question 1

3 characteristics of Dry gangrene and and 5 causes

Answer 1

1- Occur in parts with scanty tissue fluid and poor collateral circulation e.g lower limb

2- Common in Old individuals ( senile gangrene ) and diabetic patients

3- It is dry to evaporation of tissue fluid from exposed skin

1- Gradual occlusion of arterial blood supply as caused by atherosclerosis
2- thrombosis
3- Embolism
4- Vascular spasm
5- Surgical ligation

Question 2

Pathogenesis ( 7 steps )

Answer 2

1- cutting of arterial supply lead to necrosis pale cold and insensitive

2- necrosis of blood vessels lead to diffusion of blood and stains necrotic tissue red

3- saprophytic bacteria act on protein with libration of hydrogen sulphide -> bad odor
4 - hydrogen sulphide units with iron released from haemoglobin -> black odor
5- the gangrenous part become dry and shrunken and mummified

6- line of demarcation is formed between gangrenous part and living part

7- lines of separation separation of gangrenous part as a conical stump

Question 3

4 characters of moist gangrene and 3 Causes

Answer 3

1- Affects organ rich in body fluids
2- Both venous and arterial supply are occluded
3- Toxaemia is usually severe and may end fatally
4- Gangrenous part is moist and congested

1- strangulation
2- intussusception
3- volvulus

Question 4

Infective gangrene 2 characters and 3 types in details
Gas gangrene (4)

Answer 4

1- due to infection by anaerobic bacteria
2- toxamia is marked with high mortality rate

1- Gas gangrene (4) ;
1- in lacerated wound
2- Anaerobic bacteria present in soil and fecal matter
3- Produce destructive toxin and enzymes which lead to necrosis and abundant gas accumulate in lesion
4- severe toxaemia

2- Bed Sores : Skin ulcer over the bony prominence ( sacrum & greater trochanter ) due to prolonged bed rest as paralysis

3- Lung gangrene ; putrefaction of lung abscess

Question 5

3 Causes of haemorrhage
كل نوع فيه تفاصيل خلي بالك

Answer 5

1- Trauma : involving heart & blood vessels

2- Diseases of blood vessels
1- hypertension
2- varicose vein ( piles)
3- infections : T.B
4- degenerated ( atheroma , aneurysm)
5- malignant cells invading blood vessels

3- haemorrhagic blood diseases
1- haemophilia
2- scurvy
3- purpura
4- leukaemia

Question 6

Types of haemorrhage
9 external
5 internal
3 interstitial

Answer 6

External :
1- Epistaxis
2- hemoptysis
3- hematemesis
4- Melena
5- bleeding per rectum
6- Hematuria
7- Menorrhagia
8- Metrorrhagia
9 - Bleeding from skin

Internal

1- Hemothorax
2- Hemopericardium
3- Hemoperitoneum
4- Hematocele
5- Hemoarthrosis

Interstitial

1- Petechial : small amounts of blood
2- Ecchymosis : moderate amounts of blood
3- Hematoma اشرحها

Question 7

Effect of haemorrhage

Answer 7

1- Small amounts; No effects
2- Repeated small amount ( chronic )
Cause microcytic hypochromic anemia
E.G in piles and peptic ulcer

3- moderate amount Is compensated by

1- reflex tachycardia
2- Vsaoconstriction in the skin , muscles and GIT
3- Withdrawal of tissue fluids into blood
4-protein are added from the liver
5- blood cells are added by the hyperplastic bone marrow

Massive amount : Haemorrhagic shock

Question 8

What is hyperemia And mention 2 physiological cause and one pathological cause

Answer 8

Increase in blood floor to an organ as result of active dilatation of its arterioles

Physiological
1- hyperemia in skeletal muscles during exercise
2- hyperemia in the gut following a meal

Pathological
1- in acute inflammation