Acute Kidney Injury Flashcards
What is AKI?
sudden rapid reduction in eGFR with or without oliguria/anuria – couple weeks
What is oliguria?
reduction in urine output
What is anuria?
complete cessation of urine production
What is the KDIGO criteria based on?
serum Cr or urine output
What are serum Cr levels for Stage 1 AKI?
- Based on: Baseline x1.5 more than baseline
OR - ≥26 umol/L (≥0.3 mg/dL) increase in baseline
What are urine output levels for Stage 1 AKI?
<0.5mL/kg/h for 6-12h
What are serum Cr levels for stage 2 AKI?
Baseline x2 -2.9
What are urine output levels for stage 2 AKI?
<0.5mL/kg/h for ≥12h
What are serum Cr levels for stage 3 AKI?
- Baseline x3 or over
2. ≥354 umol/L (≥4 mg/dL) increase
What are urine output levels for stage 3 AKI?
- 0.3mL/kg/h for 24h
- Anuria for 12h
- Or if patient on Renal replacement therapy (dialysis)
Which parameter do you use to determine stage if they are conflicting?
- You will use the parameter that gives the worst disease state
- (i.e.: if a patient has peed <0.5mL/lg/h in the last 6 hours but has an increase in serum creatinine 2.5 times their baseline, then you will stage their AKI as stage 2 rather than 1)
What are the possible complications for an AKI?
- Fluid overload
- Uraemia
- Metabolic acidosis
- Hyperkalaemia
What are the symptoms of fluid overload?
pulmonary oedema
What is the management of fluid overload?
- IV furosemide/ GTN infusion
2. haemodialysis if refractory
What are symptoms of uraemia?
- Uraemic encephalitis (lethargy, confusion)
2. uraemic pericarditis
What is the management of uraemia if symptomatic?
haemodyalsis
What are symptoms of metabolic acidosis?
- Confusion
- tachycardia
- Kussmaul’s breathing
- N&V
What is the management for metabolic acidosis?
- IV/PO sodium bicarbonate
2. dialysis if refractory
How do you asses fluid overload?
- JVP
- pitting oedema
- crackles on chest
- capillary refill
- BP
- HR
What are symptoms of hyperkalameia?
- Asymptomatic
- Arrhythmias
- Muscle weakness
- Cramps
- Parasthesias
- Hypotension
- Bradycardia
- Cardiac arrest
What are K levels for mild hyperkalaemia?
5.5-6
What are K levels for moderate hyperkalaemia?
6.1-6.5
What are K levels for severe hyperkalaemia?
K>6.5 OR Any K with ECG changes and symptomatic
How do you manage hyperkalamia?
- Cardiac monitor
- Calcium gluconate: 10% 30mls IV
- 10U soluble insulin
- 50mls of 50% glucose
- Also may benefit from:
- Salbutamol nebulisers
- IV furosemide
- IV sodium bicarb (if acidosis) - Stop offending cause, continuous monitoring of K+
- If refractory, start haemodyalisis
What does of calcium gluconate is given for hyperkalamia?
10% 30mls IV
Why do you give calcium gluconate in hyperkalamia?
protects the heart
What dose of soluble insulin do you give in hyperkalamia?
10U
What dose of glucose do you give in hyperkalamia?
50mls of 50% glucose
Why do you give soluble insulin in hyperkalamia?
drives excess K+ into cells and out of blood
Why do you give glucose in hyperkalamia?
avoids hypoglycaemia
What are ECG changes in hyperkalamia?
- Peaked T wave
- Wide PR interval
- Wide QRS duration
- Loss of P wave
- Sinusodial wave
- Bradycardia
When do you treat hyperkalamia?
only if severe
What investigations are done for AKI?
- Fluid assessment
- ABG/VBG, potassium & bicarb – gets quick K
- Bloods
- Hepatitis/HIV screen, vasculitic screen, myeloma screen, anti-GBM… Sepsis screen (if septic)
- KUB
- ECG
- Good medication history
How do you do a fluid assessment?
check membranes, cap refill
What bloods are ordered for AKI?
- FBC
- U&Es
- CRP
- LFTs
- CK
- clotting
How is AKI managed?
- ABCDE approach
- Find and treat cause
- STOP ANY NEPHROTOXIC DRUGS
- Fluid management
- Treat complications
- Dialysis if necessary