Condition- AKI Flashcards
What is AKI?
Abrupt loss of kidney function => retention of urea and H2O and electrolyte disregulation
Three AKI classifications based on aetiology?
- Pre-renal: Inadequate perfusion
- Intra-renal: Cellular damage/ intrinsic
- Post-renal: Urinary tract obstruction
3 commonest causes of AKI
- Renal ischaemia- hypovolaemia, hypotension, renal artery stenosis
- Sepsis
- Nephrotoxins
List some pre-renal causes of AKI
- Hypotension (shock, sepsis, anaphylaxis)
- Hypovolaemia (haemorrhage, severe D+V, severe burns)
- Renal Artery Stenosis, embolus, ACEi, NSAIDs, ARBS
- Heart Failure- cardiorenal syndrome
- Cirrhosis- hepatorenal syndrome
List some intra-renal causes of AKI
- Glomerular:
- glomerulonephritis due to SLE/ drugs
- Haemolytic uraemic syndrome
- Tubular:
- acute tubular necrosis (ATN)- nephrotoxins
- Interstitial:
- acute interstitial nephritis (AIN) (-NSAIDs, autoimmune)
- Tumour lysis syndrome
- Vascular:
- TTP
- vasculitides
- rhabdomyolysis
- Eclampsia
Most common cause of intra-renal AKI? And what can cause it/
Acute-tubular necrosis = death of tubular epithelium
Ischaemia= pre-renal causes
Nephrotoxins e.g. Aminoglycosides, heavy metals, contrast dyes, urate
Which drugs may cause Acute Intersitial nephritis and intra-renal AKI
NSAIDs
Penicillin
Diuretics
List some post-renal causes of AKI
- Luminal: stones
- Mural: malignancy, urethreal strictures
- Extramural: BPH, malignancy (pelvic)
List some symptoms of AKI
- Oligouria/ anuria (urine output less than 0.5 ml/kg/hour)
- Nausea/vomitting- fluid overload + uraemia
- SOB + orthopnoea
- Dehydration
- Confusion- uraemic encephalopathy
List some signs of AKI on physical examination
- Hypertension
- Distended bladder (if obstruction)
- Palpable kidney (if polycystic)
- Renal bruit (if renovascular disease)
- Dehydration- postural hypotension
- Fluid overload (HF, cirrhosis, nephrotic syndrome)- raised JVP, oedema, SOB
- Signs of uraemia- pericarditis, encephalopathy
- Pallor, rash, bruising (vascular disease)
What might you see in the urine of a pt with AKI?
- Haematuria= nephritic cause
- Protein= nephrotic glomerular disease
- Glucose
- Leucocyte esterase and nitrites- UTI
- Urine osmolality may change e.g. Change in Na or H2O conc
What could you look for in the blood which can be used to indicate reabsorption/secretion function of the renal tubules?
BUN: Creatinine ratio
List some of the complcations of AKI…
- Pulmonary oedema
- Acidaemia
- Uraemia
- Hyperkalaemia
- Bleeding
List some factors which lead to a poorer prognosis for AKI patients
- Age
- Multiple organ failure
- Oligouria= really bad GFR
- Hypotension
- CKD
