AKI Flashcards
Sources
https://www.nice.org.uk/guidance/ng148/chapter/Recommendations#managing-acute-kidney-injury
https://zerotofinals.com/medicine/renal/aki/
https://www.thinkkidneys.nhs.uk/aki/wp-content/uploads/sites/2/2016/02/BAPN_AKI_FINAL.pdf
What is an AKI?
Acute kidney injury
Defined as an acute drop in kidney function
What are the NICE criteria for AKI?
Any of the following:
- rise in serum creatinine of 26 micromol/litre or greater within 48 hours
- 50% or greater rise in serum creatinine within the last 7 days
- fall in urine output to < 0.5ml/kg/hour for > 6 hours in adults and > 8 hours in children & young people
- a 25% or greater fall in eGFR in children and young people within the past 7 days
What risk factors would predispose a patient to have an AKI?
CKD
HF
DM
Liver disease
Older age (> 65 years)
Cognitive impairment
Nephrotoxic meds e.g., NSAIDs, ACE-inhibitors
Use of contrast medium e.g., during CT scans
How can you divide the causes of an AKI?
Pre-renal
- most common cause
- due to inadequate blood supply
Renal
- intrinsic disease of the kidney causes reduced blood filtration
Post-renal
- caused by obstruction to the outflow of urine from the kidney, which causes back pressure into the kidney and reduced kidney function - obstructive neuropathy
Name the common causes of pre renal AKI
- dehydration
- hypotension (shock)
- HF
Name the common causes of intrarenal AKI
- glomerulonephritis
- interstitial nephritis
- acute tubular necrosis
Name the common causes of postrenal AKI
- kidney stones
- masses e.g., cancer in abdomen or pelvis
- ureter or urethral strictures
- enlarged prostate/prostate cancer
What investigations would you do for someone with suspected AKI?
Should already have done baseline bloods, as U&Es form basis of AKI diagnosis
Urinalysis - for blood, protein, leucocytes, nitrites and glucose
Protein and blood suggest acute nephritis (but can be +ve in infection)
Glucose suggest diabetes
USS of the urinary tract is used to look for obstruction but not necessary if alternative cause is found for the AKI
How would you prevent an AKI?
3Ms
Monitor
- NEWS score
- fluid balance
- daily weight
- urinalysis
- serum creatinine and electrolytes
Maintain circulation
- treat hypoperfusion adequately (e.g., give IV fluids)
Minimise kidney insults
- review
- monitor and adjust meds
What are the different stages of AKI?
Stage 1
Stage 2
Stage 3
What are the parameters for a stage 1 AKI?
Measured creatinine > 1.5-2x reference creatinine/upper limit of reference interval (ULRI)
What are the parameters for a stage 2 AKI?
Measured creatinine > 2-3x reference creatinine/ULRI
What are the parameters for a stage 3 AKI?
Measured creatinine > 3x reference creatinine/ULRI
How would you manage an AKI
4 Ms
When managing an AKI, when should you refer patients with an upper tract urological obstruction to a urologist?
Refer immediately when ≥ 1 of the following is present:
- pyonephrosis
- obstructed solitary kidney
- bilateral upper urinary tract obstruction
- complications of AKI caused by urological obstruction
Which medication should not be routinely offered to treat AKI?
Loop diuretics
When should you consider loop diuretics for treating fluid overload or oedema in an AKI patient?
While:
- an adult, child or young person is awaiting renal replacement
OR
- renal function is recovering in an adult, child or young person not receiving renal replacement therapy
What drug should you NOT offer to treat an AKI?
Low-dose dopamine
When should you refer adults, children & young people immediately for renal replacement therapy?
If any of the following are not responding to medical Mx:
- hyperkalaemia
- metabolic acidosis
- Sx or complications of uraemia (e.g., pericarditis or encephalopathy)
- fluid overload
- pulmonary oedema
When should a patient with AKI be referred to a nephrologist?
If they meet criteria for renal replacement therapy
When would you discuss Mx of AKI with a nephrologist or paediatric nephrologist ASAP and within 24 hours of detection?
When ≥ 1 of the following are present:
- possible Dx that may need specialist Tx (e.g., vasculitis, glomerulonephritis, tubulointerstitial nephritis or myeloma)
- AKI with no clear cause
- inadequate response to Tx
- complications associated with AKI
- stage 3 AKI
- renal transplant
- CKD
When the eGFR is ≤30ml/min/1.73^2, what should you do?
Consider referral to nephrologist or paediatric nephrologist (in children and young people)
In children or young people who have recovered from an episode of acute kidney injury but have hypertension, impaired renal function or 1+ or greater proteinuria on dipstick testing of an early morning urine sample, what should you consider doing?
Referring to paediatric nephrologist
