Oedema Flashcards
What is oedema?
normal response of the body to inflammation or injury.
Can be sign of infection, Increased fluid from the blood vessels, allows infection-fighting wbcs.
Can be generalised or localised
Causes of Oedema
Hypoalbuminemia (protein in plasma) Allergic reaction Obstructive flow Heart disease Liver disease Kidney disease Pregnancy Medications Obstruction of the lymphatic flow
What do Starling Forces control?
What is it’s aim?
control movement of fluid from capillaries to interstitial fluid.
Aims to maintain a Steady State.
Where does fluid move to when oedema is present?
Increased fluid moves from vascular system across the vessel wall to interstitial tissue.
Pathophysiology of oedema?
Obstruction of venous / lymph drainage
- Increased venous and capillary pressure
- Lymphoedema primary/secondary
Capillary Damage (Inflammation)
- Increased permeability due to endothelium damage
- Transfer of protein into interstitial tissue
- Caused by drugs, viral or bacterial agents, thermal or mechanical stress
- Non-pitting and localised
- Generally red/hot/tender
Reduction of effective arterial volume
- Decreased cardiac output
- Systemic vascular resistance
- Body attempts to rectify by retaining salt
Retention of Renal Na+
- Via the renin-angiotensin-aldosterone system
- Continued secretion of aldosterone
- Activated in heart failure
Arginine Vasopressin (AVP)
- Antidiuretic hormone which is responsible for regulating the body’s H2O retention
- Increased intracellular osmolarity concentration
- Reabsorption of free water and retention of Na+
- Circulating AVP elevated in chronic heart failure
Cause of localised Oedema?
- Obstruction of venous (& lymphatic) drainage of limb
- Blockage (unable to drain)
- Increased capillary pressure
- Lymph oedema (generally painless/dull heavy sensation)
- Widespread blockages affecting multiple regions
Name the other types of site specific oedema?
Anasarca – gross, generalised oedema Ascites – Peritoneal oedema (liver) Pleural oedema Cerebral oedema Pitting vs Non-pitting peripheral oedema
Causes of generalised oedema?
- Congestive Heart Failure
Impaired systolic emptying of ventricle
Increased blood in venous system, ncrease venous pressure
Amount of oedema is reflective of severity of heart failure - Nephrotic Syndrome/ Hypo albuminemia (Renal)
Large loss of proteins in urine reduces osmotic pressure - Severe nutritional deficiency
Large loss of proteins in urine reduces osmotic pressure - Cirrhosis (Liver)
Blockage of hepatic venous outflow, increase hepatic lymph
Retention of renal Na+
Decreased ability to metabolise aldosterone - Drug Induced
NSAID’s, cyclosporine, vasodilators, steroids, interleukin 2 - Idiopathic
Common to women, fluctuates in severity, aggravated by hot weather
Increased capillary permeability - Others
Hypothyroidism, pregnancy, estrogens related
Why is distribution of oedema important?
It’s a guide to its cause
Eg; (Hx – Dx/Mx, alleries)
One leg/arm: lymphatic obstruction Generalised - noticeable in face = hypo proteinemia - most pronounced in am - more extensive in legs = congestive heart failure - worst in evenings
Types of oedema common to Pod patients?
- Lymphoedema (injury, surgery, infection)
- Congestive Cardiac Failure (poor control of Blood Pressure)**
- Renal Failure (increased fluid volume)
Which is the most common form of oedema?
Pitting Oedema
Causes of pitting oedema?
- Intravascular issues
(lymphatics temporarily drain fluid causing pitting) - Increased venous BP causes back up into the capillaries
(increased hydrostatic pressure causes the oedema) - Can be generalized or local
What are the common local caused of venous insufficiency?
Varicose veins
Thrombophlebitis
Blockage (DVT/Mass)
Sign & Symptoms of Pitting Oedema?
- swelling or puffiness of the skin,
- skin discolouration
- areas of skin that temporarily hold the imprint of your finger when pressed (known as pitting oedema)
- aching, tender limbs
- stiff joints
- weight gain or weight loss
- raised blood pressure and pulse rate
Why is there no indentation in non-pitting oedema?
Lymphatic drainage is blocked
If skin is pressed the fluid cannot drain
