An abnormal increase in interstitial fluid
Name the causes of Oedema?
Increased hydrostatic pressure ( regional or generalised) Reduced plasma oncotic pressure ( reduced albumin) Lymphatic obstruction Sodium retention Inflammation
What is generalised oedema?
Widespread accumulation of fluid in subcutaneos tissues and serous cavities
What is pitting oedema?
Pitting edema: Observable swelling of body tissues due to fluid accumulation that may be demonstrated by applying pressure to the swollen area (such as by depressing the skin with a finger).
Name the common causes of generalised Oedema?
Left Ventricular failure - high BP
kidney and hepatic problems can both lead to drop in oncotic pressure in blood. (they regulate protein levels in blood)
nb pathophysiology of generalised oedema is complex. A lot of theories surrounding Renin ang system faultiness leading to excess Na retention
Summarise the process which causes oedema?
Low renal blood flow renin angiotensin aldosterone absorption of sodium and water from kidneys generalised oedema Renin- released from kidney Adosterone-acts on the kidneys to stimullate reabsorption of salt and water Reduced renal blood flow activation of the renin-angiotensin system =arrow
How is Pulmonary Oedema caused?
WHats the consequence of this? (symptoms and what disease is the patient susceptible to)
Pulmonary oedema is usually the result of raised pulmonary capillary hydrostatic pressure due to pulmonary venous congestion.
The most common cause of this is left ventricular failure.
Consequences include breathlessness and susceptibility to pneumonia.
Name the most common cause of Pulmonary Oedema?
Left ventricular failure
Name the consequences of Pulmonary Oedema?
Breathlessness(typically worse laying flat-orthopnoea) and susceptibility to pneumonia. Breathlessness(dyspnoea) is the main symptom.
In an pulmonary oedema , fluid accumalates first in the ............ ........ and then eventually spills into the .......... ........
First- Interstitial space Second-Alveolar Spaces
What causes a Cerebral Oedema?
Cerebral Oedema is usually the result of breakdown of the normal capillary barrier
Where does a cerebral oedema usually occur?
Typically occurs in brain tissue surrounding lesions such as cerebral contusions, haemorrhages, infarcts and tumours.
What does a cerebral oedema cause?
Rise in intra-cranial pressure which can be fatal.
Name some stratagies to reduce Cerebral Oedema?
Strategies to reduce ICP include raising the head, inducing dehydration with drugs (e.g. mannitol), surgical decompression.
What does general oedema cause?
pitting peripheral oedema
Pathological clot formation in a blood vessel
Name the three broad factors that predispose an individual to thrombosis?
Changes in vessel wall Changes in blood flow Changes in blood coagulability
What condition is almost always related to vessel wall injury caused by atherosclerotic plaques?
How does arterial Thrombosis cause infarction of tissue?
Complete blockage (occlusion) of the artery by thrombus causes infarction of the tissue supplied by the artery
How does arterial Thrombosis cause ischaemia of tissue?
Narrowing(stenosis) of the artery by thrombus causes ischaemia of the tissue supplied by the artery.
What condition is related to stasis of blood in a cardiac chamber?
Cardiac Thrombosis is usually related to stasis of blood in a caridac chanber, most commonly the left atrium in association with atrial fribulation or the left ventricle in association with a myocardial infarct
What does a prior myocardial infarction leave you more susceptible to?
Left ventricular thrombosis
What causes cardiac thrombosis?
Abnormal cardiac contractibility and myocardial injury
What is the most important potential complication of cardiac thrombosis?
Systemic embolisation is the most important potential complication
What is an embolism?
An embolus is a detached mass within the circulatory system that is carried in the blood to a site distant from its point of origin
Where do most emboli originate from?
Most emboli are fragments of dislodged thrombus (thromboemboli).
Name some rare types of embolic material?
Fat air amniotic fluid tumour
What can an emboli lead to?
Emboli are important because they can lodge in vessels and block them off.
Where do most venous thrombo embolism originate from?
Deep ;eg vein (DVT)
Name the most significant consequence of a venous thrombo-embolism?
Pulmonary (thrombo)embolism Embolism to the lungs with blockage of a pulmonary artery is the most significant consequence.