AKI, CKD and dialysis Flashcards
Define AKI
Acute kidney injury is the short term decline in renal function, measured by either a rise in creatinine from baseline OR a decline in urine output
Describe the epidemiology of AKI
VERY common in hospital eg. 10-20%
Describe the aetiology of AKI
3 main groups of causes:
- Pre-renal (most common): hypovolaemia eg. sepsis, decreased renal blood flow eg. drugs, RAS, hypotension
- Renal (3rd most common): ATN, TIN, etc
- Post-renal (2nd most common): stones, neoplasms, BPH
Describe the presentation of AKI
Usually detected in patients with other illness
- Fatigue, malaise
- Uraemia: confusion, CP, pruritis
- Palpitations
- SOB
Describe the investigations for AKI
Detecting AKI: U+Es
Cause of AKI:
-Urine dip + MCS
-Bloods: FBC, CRP, LFTs, VBG + culture (if indicated)
-USS
-> if nothing on above to suggest pre/post renal cause, refer to renal + antibodies, consider biopsy
+ monitoring: ECG, CXR
Describe the signs of AKI on examination
- Fluid status exam: may be dry (hypovolaemic) or overloaded (HF)
- Confusion
- Pericardial friction rub
- Signs of causative illness eg. vasculitic rash, arthritis
Describe the general management of AKI (not specifics)
A to E approach
- Gain IV access, take bloods
- ECG and cardiac monitor if available
STOP:
- Sepsis 6 if indicated
- Stop nephroToxic drugs (NSAIDs, ACEi/ARBs, aminoglycosides)
- Optimise BP/hypovolaemia: fluid resus + fluid balance chart
- Prevent harm: find + treat cause
Describe the management of hyperkalaemia
- Continuous cardiac monitor (after ECG)
- Start Ca gluconate 10ml 10%
- Start insulin + dextrose infusion- 10 units Actrapid and 50mls of 50% dextrose STAT + measure BM
- Nebulised salbutamol 10-20mg
- Repeat ECG and bloods
Which fluids should you use for resus in AKI?
Best is balanced crystalloid (Hartmanns, Ringers lactate) unless hyperkalaemia/rhabdo
What are the ECG changes in hyperkalaemia?
Tented T waves
Flattened p waves
Broad QRS
What are the indications for emergency dialysis?
Refractory pulmonary oedema Resistent hyperkalaemia Refractory metabolic acidosis Uraemic pericarditis Uraemic encephalopathy
At what level of hyperkalaemia should you commence treatment?
Mild (5.5-6): look for and treat underlying cause
Mod (6.0-6.4): ECG and insulin dextrose +/- Ca gluconate + monitor if ECG changes present
Sev (>6.5): ECG, cardiac monitor, Ca gluconate, insulin dextrose
Describe the management of acidosis in AKI
Seek expert advice
pH <7.2 is indication for sodium bicarb
*If serum bicarb <16, no fluid overload present
Describe the management of pulmonary oedema in AKI
A to E approach Sit upright Start high flow O2 eg. 15L via non-rebreath mask IV GTN Consider IV furosemide with senior input
Describe the causes of ATN
Ischaemia eg. from hypovolaemia
Contrast
Toxins
Drugs: aminoglycosides
Describe the causes of TIN
Immune-mediated injury due to drugs commonly: Rifampicin Sulfa drugs Pee pills (diuretics) Pain relief (NSAIDs) Penicillin PPIs Phenytoin
Name the indications for renal biopsy
- Renal AKI
- CKD with no clear aetiology
- Haematuria ?cause
- Nephrotic syndrome in adults/ non-steroid sensitive in children
Define CKD
Chronic kidney disease is a chronic impairment in kidney function present for 3+ months, characterised by a decline in GFR, proteinuria or haematuria
Describe the staging of CKD
Staged in 2 ways eGFR (G) 1: 90-120 2: 60-89 3a: 45-59 3b: 30-44 4: 15-29 5: <15
ACR (A)
1: <3
2: 3-30
3: >30
Describe the epidemiology of CKD
Quite common!
Increases with age
Increasing incidence with time
Black > white people
Describe the aetiology of CKD
Most commonly:
- DM
- Hypertension
- Glomerular nephrotic and nephritic syndromes
- PKD
Describe the consequences of CKD in relation
to the function of the kidneys
- Sodium and fluid imbalance
- Electrolyte abnormalities (K, phos)
- Waste buildup: azotaemia and increased serum creatinine
- Endocrine abnormalities: renal osteodystrophy, anaemia
Describe the presentation of CKD
Often asymptomatic, detected incidentally
Non-specific: fatigue, malaise, nausea, anorexia
Pruritis
SOB, swelling
Palpitations
Describe the signs of CKD on examination
May have none
- Pedal oedema
- Pallor
- Signs of causative disease eg. diabetic retinopathy, HTN
