1/3 Flashcards
What is:
- creatinine
- urea
Creatinine
- break down of creatine (produced by muscle) - this is not reabsorbed so can be a good measure of flow through the kidneys (SERUM creatine in AKI)
Urea
- further breakdown product that is taken out through the kidneys
Describe the passage fluid takes from through the nephron
Glomerulus
Bowman’s capsule
Proximal convoluted tubule
Loop of henle
Distal convoluted tubule
Distal collecting duct
What are the causes of AKI
Pre-renal
- hypovolaemia (GI loss, haemorrhage or burns)
- hypotension
- renal artery stenosis/aortic dissection
Renal (problems with nephrons)
- DAMN drugs
- Acute tubular necrosis (epidethial cells of nephron die - myoglobin also damages cells)
- acute interstitial nephritis (inflammation of the intersititium of kidney)
- glomerular disease (anti glomeular basement membrane disease (Good pastures disease), post infection glomerulitis)
- thrombosis/emboli
Post-renal (obstruction to urinary flow)
- External (external tumour or BPH)
- Internal (stricture, tumour or renal stones)
What happens to GFR during AKI?
It reduces - hence raise in serum creatinine
What do each of the following on urine sample suggest
- muddy brown casts
- red casts
- wbc casts
Muddy brown = necrosed cells = acute tubular necrosis
Red casts = inflamed cells = glomerulonephritis
WBC = acute intiersital nephritis
How do you calculate fluid maintenance for paediatric pts?
421 rule
4ml/kg/hr for first 10kg
2ml/kg/hr for next 10kg
1ml/kg/hr for weight above 20kg