Oedema means abnormal accumulation of fluid
in the tissue space and serous sacs . The liquid may be abnormally accumulated
in loose subcutaneous tissue like lower eyelid . tissues in external genitalia
, serous sacs like peritoneum ., pleura , pericardium , dependent part of the
body like leg .
Cause of oedema ….
1.
due to the inflammation (
inflammatory oedema ) – Inflammatory oedema is caused by the increased
capillary permeability due to the liberation of histamine and leucotaxime , and
increased hydrostatic pressure at the arterial end of the capillaries .
2.
Due to hypersensitiveness (
Angioneurotic oedema ) - Angioneurotic
oedema occurs due to the liberation of histamine and it is mostly found in
tongue and lips .
3.
Due to venous obstruction – The
lumen of the vein may be occluded by phlebothrombosis or thrombophlebitis . The
venous obstruction may be caused by the enlarged lymph node or space occupying
lesion pressing on vein .
4.
Due to lymphatic obstruction –
Oedema in lymphatic obstruction is non –pitting type .
5.
Due to severe anaemia – It is
due to chronicblood loss . The best example is Hookworm infection .
6.
Due to renal disease – Best
example is acute or sub-acute glomerulonephritis .
7.
Due to cardiogenic cause – like
congestive cardiac failure .
8.
due to malnutrition-
Hypoproteinaemia leads to oedematous condition .
Types of oedema …….
1.
Fluid oedema - In this type fluid collects on intercellular
space . This type of oedema is pitting type . here the tissue will be pale ,
swollen , soft and inelastic .
2.
Solid oedema – In this type ,
there will be no pit on pressure , so non pitting type . The tissue will be
pale , swollen , tough and inelastic . This is found in filariasis due to lymphatic
obstruction .
