302 Pathophysiology and cytopathology of ascites Flashcards
What are the 6 causes of ascites?
Fluid
Flatus
Faeces
Fat
Faetus
Neoplasia, Inflammation, Infection, or rarities like sarcoidosis
What are the clinical presentations of ascites?
Flank dullness on examination, shifting dullness, a fluid wave, evidence of pleural effusions
What causes caput medusae?
Portal hypertension
Dilated superficial (superior and inferior) epigastric veins radiating from a central large venous varix
What is paracentesis?
the perforation of a cavity of the body or of a cyst or similar outgrowth
What is the equation for filtration/reabsorption rate?
Qf = P eff (Difference between hydrostatic/blood pressure minus oncotic pressure) x K f (permeability x exchange area
Affected by:
Change in hydrostatic pressure
Change in oncotic pressure
Change in permeability
Change in exchange area
What are serous membranes?
The outer lining of organs and body cavities of the abdomen and chest, including the stomach
Eg. Pericardium, pleura, peritoneum, tunica vaginalis of testis
What are the limitations for clinical detection of effusions in different serous membranes?
Ascites 500 ml
pleura 300 ml
pericardium 50ml
Effusions are always pathological
What is a transudate effusion?
Plasma filtrate with low protein content
Caused by change in hydrostatic or oncotic pressure
What is an exudate effusion?
Unfiltered plasma with high protein content
Caused by change in vascular permeability or exchange area
What are the causes of portal hypertension?
liver cirrhosis (80%)
alcoholic hepatitis
chronic cardiac failure
constrictive pericarditis
What are the causes of hypoalbuminaemia?
nephrotic syndrome
protein losing enteropathy
malnutrition
What is the role of albumin?
Helps keep fluid from leaking out of your blood vessels into other tissues
What are the different causes of ascites?
Portal hypertension liver cirrhosis (80%)
= hydrostatic
Hypoalbuminaemia
= oncotic
Peritoneal disease
= permeability
= exchange area
Others:
chylous ascites (lymphatic blockage e.g. in malignancy)
haemoperitoneum
pancreatic disease
sarcoidosis
What is peritoneal disease?
A pattern of metastatic disease where cancer has spread from where it initially started into the lining of the abdominal cavity
What is SAAG?
SAAG = serum albumin – ascites albumin
A high gradient (SAAG >1.1 g/dL) indicates portal hypertension and suggests a nonperitoneal cause of ascites
What does Pale yellow and watery ascites fluid indicate?
Transudate from CCF cirrhosis protein etc
What does turgid and yellow to white ascites fluid indicate?
Infection, malignancy, pancreatitis