AKI Sarah Edwards – ST5 renal

Objectives Be able to recognise acute kidney injury Understand risk factors for developing AKI Form a simple differential diagnosis for cause of AKI Select appropriate investigations Know how to treat hyperkalaemia and initiate management of AKI

Scenario 73 year old man presents to A&E with 48 hr diarrhoea and vomiting. Can’t remember passing urine today. He’s been waiting for a while to be seen, a nurse hands you some blood results that the lab have phoned through; Na 135 K 6.7 Ur 20 Creat 258

What are you thinking?

He’s got an AKI Think of Simple Differential Diagnosis Is this? Pre-renal Renal Post-renal Or mixture?

What do you want to do?

History He has a PMH of hypertension. He takes atenolol and ramipril Non smoker, no alcohol

Examination BP 100/65 HR 64 RR 20 SpO2 97% RA Dry mucous membranes No oedema Chest clear, Abdo soft non tender, HS normal

Is this pre-renal, renal or post-renal?

What next? Life saving things first…

Treat the potassium Principles of treating Hyperkalaemia 1)Cardiac stabilisation = calcium gluconate 2)K redistribution therapy = insulin/ dextrose 3)Ensure excretion, i.e patient is passing urine 4)Others calcium resonium, dialysis

Investigations Urinalysis and MSU US KUB Renal bloods screen -ANCA, ANA, DsDNA, antiGBM, C3C4, -Myeloma screen sFLC, SPE -Renal referral ? Biopsy if intrinsic renal cause suspected

Management Treat hyperkalaemia Fluid management – catheter, fluid balance IV fluids and repeated examination Medication review – stop nephrotoxins, caution renal excreted drugs Look for and treat cause

Management Pre-renal – fluids and address cause Renal – renal team Post-renal – urinary catheter, if obstruction above the bladder needs nephrostomy

When do we dialyse? Depends on the complications of AKI…

Complications of AKI Hyperkalaemia Pulmonary oedema Metabolic acidosis

Key points AKI is common, particularly if pre-existing CKD, elderly, diabetic, heart failure,taking nephrotoxic medication Work through potential pre-renal, renal and post-renal causes Examination, urinalysis and USS are key Insulin/dextrose is only a temporary treatment measure for hyperkalaemia

Questions