AKI

Question 1

Sources

Answer 1

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

Question 2

What is an AKI?

Answer 2

Acute kidney injury

Defined as an acute drop in kidney function

Question 3

What are the NICE criteria for AKI?

Answer 3

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

Question 4

What risk factors would predispose a patient to have an AKI?

Answer 4

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

Question 5

How can you divide the causes of an AKI?

Answer 5

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

Question 6

Name the common causes of pre renal AKI

Answer 6

• dehydration
• hypotension (shock)
• HF

Question 7

Name the common causes of intrarenal AKI

Answer 7

• glomerulonephritis
• interstitial nephritis
• acute tubular necrosis

Question 8

Name the common causes of postrenal AKI

Answer 8

• kidney stones
• masses e.g., cancer in abdomen or pelvis
• ureter or urethral strictures
• enlarged prostate/prostate cancer

Question 9

What investigations would you do for someone with suspected AKI?

Answer 9

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

Question 10

How would you prevent an AKI?

Answer 10

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

Question 11

What are the different stages of AKI?

Answer 11

Stage 1

Stage 2

Stage 3

Question 12

What are the parameters for a stage 1 AKI?

Answer 12

Measured creatinine > 1.5-2x reference creatinine/upper limit of reference interval (ULRI)

Question 13

What are the parameters for a stage 2 AKI?

Answer 13

Measured creatinine > 2-3x reference creatinine/ULRI

Question 14

What are the parameters for a stage 3 AKI?

Answer 14

Measured creatinine > 3x reference creatinine/ULRI

Question 15

How would you manage an AKI

Answer 15

4 Ms

Question 16

When managing an AKI, when should you refer patients with an upper tract urological obstruction to a urologist?

Answer 16

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

Question 17

Which medication should not be routinely offered to treat AKI?

Answer 17

Loop diuretics

Question 18

When should you consider loop diuretics for treating fluid overload or oedema in an AKI patient?

Answer 18

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

Question 19

What drug should you NOT offer to treat an AKI?

Answer 19

Low-dose dopamine

Question 20

When should you refer adults, children & young people immediately for renal replacement therapy?

Answer 20

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

Question 21

When should a patient with AKI be referred to a nephrologist?

Answer 21

If they meet criteria for renal replacement therapy

Question 22

When would you discuss Mx of AKI with a nephrologist or paediatric nephrologist ASAP and within 24 hours of detection?

Answer 22

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

Question 23

When the eGFR is ≤30ml/min/1.73^2, what should you do?

Answer 23

Consider referral to nephrologist or paediatric nephrologist (in children and young people)

Question 24

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?

Answer 24

Referring to paediatric nephrologist