Recognition of AKI

Rise in Urea & Creatinine +/- decreased urine output

Red flags

Decrease in urine output (<40ml/min)

• • is there urinary obstruction?

(Sustained) hypotension, secondary to..

• • dehydration / hypovolaemia
  • anti-hypertensives
  • infective process / sepsis

Staging

Risk factors

Post-operative phase:

• • • anaesthetic-induced peri-operative hypotension
    • blood loss – hypovolaemia
    • concurrent infections

Nephrotoxins:

• • ACEi
  • ÁRB
  • NSAIDs
  • COX II inhibitors
  • Recent IV iodine contrast imaging
  • Interstitial renal disease

The following patients are generally more susceptible to develop AKI:

• • Female gender
  • Older age
  • Black race
  • CKD
  • Diabetes Mellitus
  • Chronic heart/lung/liver disease

Prevention of AKI

General instructions for management

Optimise circulation where you suspect it is inadequate

• • fluid resuscitation where required
  • stop all anti-hypertensives
  • treat sepsis with appropriate antibiotics (be wary with gentamicin, trimethoprim & co-trimoxazole if possible).

Diagnosis, Essential tests include:

• • Blood tests: U&Es, bicarbonate, FBC
  • Accurate fluid balance – catheterise and record hourly urine output. Ask nurses for this specifically as it will not be strictly performed in those with low risk of AKI.
  • Urinalysis:
    • if evidence of infection: treat and repeat when infection is resolved
    • if no evidence of infection, but protein +/- blood on dipstick request intrinsic renal screen (ANA, ANCA, ENA, immunoglobulins, complement, myeloma screen)

Removal of potential nephrotoxins

• • nephrotoxic drugs
  • avoid further IV-contrast imaging unless required, then provide reno-protection before and after scan.
  • adjust essential drugs appropriately for renal function

Further Reading

Top Fluid Tips (2014)

AKI Guidelines, _{[StaffNet Source]}

EdRen Handbooks

Electrolyte replacement, _{[StaffNet Source]}

Endocrine and Diabetes, _[StaffNet]