AKI

Question 1

What is the definition of AKI?

Answer 1

Failure of renal excretory function due to reduction of the GFR
Abrupt sustained rise (for 1-7 days being longer than 24 hours) in serum urea and creatinine
Creatinine from >1.5 times from baseline
Urine output from <0.5mL/kg/h >6h

Question 2

How common is AKI?

Answer 2

15% of adults admitted to hospital develop AKI

Question 3

What is the pathophysioloyg of AKI’s?

Answer 3

• GFR is controlled by prostaglandins and angiotensin II
• Leads to failure of:
• Erythropoietin production
• Vitamin D hydroxylation
• Regulation of acid base balance
• Regulation of salt and water balance
• Blood pressure control
• Classified as prerenal, renal or postrenal

Question 4

What are the risk factors/aetiology of AKI?

Answer 4

• Post surgery
• Pre-renal failure:
• Fluid depletion
• Hypotension
• Impaired cardiac pump efficiency
• Vascular disease limiting renal flow
• NSAIDs
• ACE inhibitors
• Renal:
• Systemic infection
• Nephrotoxic drugs
• Renal parenchymal disease
• Post renal:
• Enlarged palpable kidney/bladder
• Large prostate
• Pelvic masses

Question 5

What are the sign/symptoms of AKI?

Answer 5

↓ in excretion of nitrogenous waste – normally urea is measured 
•	Weakness
•	Fatigue
•	Anorexia
•	Pruritis
•	Bruising
•	Nausea/vomiting
•	Breathlessness – due to anaemia and pulmonary oedema 
•	Metal confusion
•	Seizures
•	Coma

Question 6

What investigations are conducted for suspected AKI?

Answer 6

• FBC
• ↓ RBC
• ↑ ERS
• U&E’s
• ↑ Urea
• ↑ Creatinine
• ↑ potassium
• ↑ HCO3 = metabolic acidosis
• ↓ Ca
• ↑ phosphate
• eGFR
• Urine dipstick
• ↑ specific gravity in pre renal
• ↓ Na in intrinsic
• US
• Renal biopsy – for unexplained AKI

Question 7

What are the surgical treatments for AKI?

Answer 7

• Catheter

* Dialysis/haemofiltration

Question 8

What are the pharmacological treatments for AKI?

Answer 8

• Fluids

* Blood transfusion

Question 9

What are the non pharmacological treatments for AKI?

Answer 9

• Enteral nutrition
• Restrict Na and K
• Avoid nephrotoxic drugs