Renal Failure Flashcards
AKI definition
An acute drop in kidney function
> 25 umol/L rise in creatinine in 48 hours
50% rise in creatinine in 7 days
<0.5ml/kg/hour urine output for >6 hours
AKI risk factors (8)
Chronic kidney disease Heart failure Diabetes Liver disease >65 years old Cognitive impairment Nephrotoxic medications e.g. NSAIDs/ACE inhibitors Use of contrast medium e.g. CT Scan
AKI causes
Pre-renal (most common)
Inadequate blood supply
Dehydration, hypotension, heart failure, renal artery stenosis
Intrinsic Renal Reduced filtration of blood Glomerulonephritis Interstitial nephritis Acute tubular necrosis
Post-Renal Obstruction to outflow of urine Kidney stones Masses e.g. cancer in abdomen or pelvis Uretral strictures Enlarged prostatectomy
AKI investigations
Urinalysis
Protein/blood - acute nephritis
Leukocytes/nitrites - infection
Glucose - diabetes
Ultrasound of urinalysis tract - obstruction
AKI stages
- Serum creatinine >26umol/L or 1.5-1.9 x baseline
- 2.0-2.9 x baseline
- > 3 x baseline
AKI management
Treat underlying cause
Pre-renal: correct volume depletion via circulatory support, correct any sepsis
Renal: refer for biopsy and specialist treatment
Post-renal: catheter, nephrostomy or urological intervention
CKD definition
Abnormal kidney structure or function, present for >3 months, with implications for health
CKD risk factors (6)
Diabetes Hypertension Age related decline Glomerulonephritis Polyscystic kidney disease Medications e.g. NSAIDs, PPIs, lithium
CKD classification
Based on eGFR, presence of albuminuria and the cause of kidney disease
CKD classification by eGFR
G1 - >90 G2 - 60-89 G3a - 45-59 G3b - 30-44 G4 - 15-29 G5 - <15 (kidney failure)
CKD stage G1 eGFR
> 90, only CKD if other evidence of kidney damage
CKD stage G2 eGFR
60-89, only CKD if other evidence of kidney damage
CKD stage G3a eGFR
45-59
CKD stage G3b eGFR
30-44
CKD stage G4 eGFR
15-29
