Chemical Pathology of GERR Flashcards
What is the test tube with yellow top for
- Electrolyte profile ( U+E )
What is the test tube with purple top for
- keeps blood without coagulating
- used for complete blood picture
What is U + E
- urea and electrolyte ( aka electrolyte profile )
- commonest blood results;t
- 7 components
What are the 7 components of U+E profile
1- Sodium 2- Potassium 3- Chloride 4- CO2 ( total CO2/ Bicarbonate ) 5- Urea 6- Creatinine 7- eGFR ( estimated glomerular filtration rate )
What is the purpose of Chloride in the electrolyte profile , and what are possible abnormalities that could be seen
- chloride tracks sodium to balance out net charge in body ( should be similar )
- patient with severe vomiting will have low chloride and high sodium
What is the purpose of CO2 in the electrolyte profile , and what are possible abnormalities that could be seen
- all the dissolved CO2 in blood , usually made of bicarbonate
- abnormality might mean acid-based problem in body
- low level of bicarbonate = metabolic acidosis
What is the purpose of urea in the electrolyte profile , and what are possible abnormalities that could be seen
- urea is end point of protein metabolism
- High levels = GI bleeding , dehydration , Kidney failure
What is the purpose of Creatinine in the electrolyte profile , and what are possible abnormalities that could be seen
- waste product of muscle metabolism
- More muscle = more creatinine
- large rise compared to previous value = Acute kidney injury
What is the purpose of eGFR in the electrolyte profile , and what are possible abnormalities that could be seen
- calculated using equation by lab
- uses age , gender and creatinine
- reduced eGFR = kidney failure
- chronic kidney disease is graded by eGFR rate
What are the conditions fo your blood if sodium levels are low
- blood is dilute
- low level of osmolality
What are the conditions fo your blood if sodium levels are high
- blood is concentrated
- high osmolality
Should the osmolality of your blood and brain cells be in equilibrium
- yes
What happens if patient becomes hyponatraemic
- blood becomes very dilute
- mismatched of osmolality between blood and fluid in brain cells
- water will move by osmosis from blood to brain to try and gain equilibrium
- brain as a result will swell up ( cerebral oedema )
What happens when a patient develops cerebral oedema
- brain expands and moves down the foramen magnum hole at the bottom of the Brian
- vital structures of the brain stem get compressed and stops you breathing
- result = death
Causes of Hyponatraemia
- dehydration ( vomiting / diarrhoea) : hypovolaemic
- SIADH ( ADH secretion problems )
- Fluid accumulation ( heart failure , liver failure ) : hypervolaemic
