AKI Flashcards
(15 cards)
What is acute kidney injury (AKI)?
A sudden reduction in kidney function, leading to retention of waste products, fluid, and electrolyte imbalance; often reversible if treated promptly
What are the main criteria for diagnosing AKI according to NICE?
- Rise in serum creatinine ≥26 micromol/L within 48 hours
- ≥50% rise in serum creatinine within 7 days
- Urine output < 0.5 mL/kg/hour for >6 hours in adults (or >8 hours in children)
What are common risk factors for AKI?
Chronic kidney disease
Age >65
Sepsis
Hypovolemia
Use of nephrotoxic drugs (NSAIDs, ACE inhibitors, ARBs, diuretics)
Diabetes
Heart failure
Liver disease
Recent use of iodine-based contrast media
What initial investigations should be performed in suspected AKI?
- Serum creatinine and UEs
- Urinalysis (dipstick for blood, protein, leukocytes, nitrites, glucose)
- Fluid balance assessment
- Renal ultrasound if obstruction or no clear cause
What are key steps in the management of AKI?
- Treat underlying cause (e.g., sepsis, hypovolemia, obstruction)
- Stop nephrotoxic drugs if possible
- Monitor fluid balance and electrolytes
- Consider specialist referral if severe or unclear cause
When should renal ultrasound be performed in AKI?
- Immediately if pyonephrosis is suspected
- Within 24 hours if no clear cause or risk of urinary tract obstruction
What are complications of untreated or severe AKI?
Hyperkalemia
Metabolic acidosis
Pulmonary edema
Uremia
Chronic kidney disease
Death
How can AKI be prevented in at-risk patients?
Identify and monitor high-risk patients
Avoid nephrotoxic drugs when possible
Ensure adequate hydration, especially before procedures using contrast
Monitor renal function closely during acute illness
what are the 5 most common causes of AKI
- Sepsis
- Major surgery
- Cardiogenic shock
- hypovolaemia
- Drugs
DAMN drugs
what are the “nephrotoxic drugs”
Diurectics / Digoxin
ACE-i / ARBs
Metformin / Methotrexate
NSAIDs
How many stages are there in AKI (Acute Kidney Injury) according to NICE/KDIGO?
Three stages:
Stage 1 (mildest)
Stage 2 (moderate)
Stage 3 (most severe)
AKI stage 1 criteria
-
Serum creatinine Increase by ≥26 μmol/L within 48 hours OR
Increase to 1.5–1.9 × baseline (within 7 days) - Urine output < 0.5 mL/kg/hr for >6 consecutive hours
AKI stage 2 criteria
- Serum creatinine Increase to 2.0–2.9 × baseline
- Urine output < 0.5 mL/kg/hr for >12 hours
AKI stage 3 criteria
-
Serum creatinine Increase to ≥3 × baseline OR
Serum creatinine ≥354 μmol/L OR
Initiation of renal replacement therapy (RRT) -
Urine output < 0.3 mL/kg/hr for >24 hours OR
Anuria for ≥12 hours
what is the NICE criteria to stop ACE-i after initiation in terms of serum Cr level
NICE guidelines state that a newly-started ACE-inhibitor should be stopped if the creatinine rises to more than 30% of baseline values after 2 weeks
