Acute Kidney Injury

Question 1

Diagnosis of AKI

Answer 1

Rise in Creatinine > 26 micromol/L in 48 hrs (above baseline)
Rise in Creatinine > 50% ( best figure in last 6 months ) within 7 days
Urine output < 0.5ml/kg/hr for > 6 consecutive hours

Need only one of these criteria

Question 2

Which one has got AKI:

1) 23 F , baseline Cr-60 , presented with Cr-100, normal UO
2) 30M, 70kg, baseline Cr-100, admitted with Cr-120 , UO 50ml/hr
3) 80 F, 50kg, a/w long lie on the floor , baseline Cr-200, now Cr-250, UO-30ml/hr
4) 20M, involved in car accident , injury to abdomen , Baseline Cr-60 , now Cr-80 , UO- 10ml/hr for 7hrs

Which is the sickest?

Answer 2

1) Yes
2) No
3) Yes
4) Yes

3 or 4 (abdo damage could mean crushed kidney) is the sickest

Question 3

45F , just had bilateral nephrectomy for RCC , baseline Cr-80 , now Cr-100 , No UO for last 2 hrs .
Has she got AKI ?
Does she need RRT (Renal Replacement Therapy)?
Why?

Answer 3

Yes she has AKI as has no kidneys

RRT is needed

Question 4

Normal creatinine level for male middle aged

Answer 4

50-60

Question 5

Types of causes of AKI

Answer 5

Pre-renal
Renal
Post-renal

Question 6

Pre-renal causes of AKI

Answer 6

(Reduced blood flow to kidney)
Fluid loss from body - diarrhoea and vomiting
Trauma
Burns
Heart failure
Any cause of shock
(Sepsis)

Question 7

Renal causes of AKI

Answer 7

Drugs e.g. steroids (NSAIDs)
Infection/Inflammation of kidney
Trauma
Renal nephritis

Question 8

Post-renal causes of AKI

Answer 8

Kidney stone
Cancer of ureter, bladder or prostate (in men)
Luminal - stone in ureter, blood clot in ureter
Stone in bladder or blood clot in bladder
Prostate enlargement

Question 9

Assessment of patient with AKI

Answer 9

Start with ABCDE (patient is able to talk to you)
History - assess pre-renal, renal, post-renal
Physical examination
Differential diagnosis
Investigations
Initial management

Question 10

As well as bloods, what other investigations can be done?

Answer 10

Urine dip
Ultrasound of kidney, ureter, bladder (blood clot tumour)
Monitoring of urine output

Question 11

Urine dip - what does it show?

Answer 11

Protein

Question 12

True or False:

In initial management of AKI, its always ok to prescribe some IV fluid

Answer 12

Mostly True except in case of heart failure

Question 13

Medical emergency associated with AKI

Answer 13

Hyperkalemia

Failing kidneys wont be able to excrete potassium

Question 14

Other than a blood test, what else could show hyperkalemia

Answer 14

ECG

large T waves and small/indiscernible P waves in V2-6

Question 15

Management of hyperkalemia

Answer 15

First Insulin and Dextrose
Then:
Calcium gluconate (membrane stabiliser of heart)
IV fluid
Salbutamol (B2 agonist)
(calcium resonium - but can cause serious constipation)

Question 16

In management of hyperkalemia, what is action of insulin

Answer 16

Drive potassium from blood stream into cell

Question 17

True or False:

in management of hyperkalemia, calcium gluconate helps reduce potassium levels in blood

Answer 17

False
Has no effect on potassium in the blood
Is a membrane stabiliser of heart

Give to any patient with ECG changes

Question 18

Management of AKI

Answer 18

Stop nephrotoxic drugs
Identification of risk factors
Thinking about common causes
Assessment of the patient with AKI
Investigations
When to refer to a nephrologist 
Indications for dialysis

Question 19

What is dialysis

Answer 19

The process of removing excess water, solutes, and toxins from the blood in people whose kidneys can no longer perform these functions naturally.

Question 20

Risk factors of AKI

Answer 20

Older Age
Comorbidities
Drugs (e.g. antibiotics)
Reason of admission (e.g. heart failure, vomiting, diarrhoea, sepsis) - being in hospital increases AKI risk

Question 21

Investigations of AKI

Answer 21

full examination, creatinine, urea, electrolytes, liver enzymes, clotting, glucose, urine dipstick, autoantibodies (anti-GBM, ANCA), renal USS
Imaging (CT-KUB?)

Question 22

Things to do before referral to nephrologist

Answer 22

First treat/stabilise and hyperkalemia
Proper history and examination (blood pressure, medication on)
Blood tests & Imaging
IV fluid
Urine dip sticks
Review of drugs
Fluid balance ( intake /output )
Current volume status (dry/dehydrated or wet/HF)

Question 23

When to refer to nephrologist

Answer 23

Treat the urgent causes first !
Hyperkalaemia or fluid overload unresponsive to medical treatment
Urea > 40mmol/L +/- signs of uraemia (e.g. encephalopathy, pericarditis etc)
No obvious cause
Creatinine > 300 or rising > 50micromol/L per day

Question 24

Complications fo AKI

Answer 24

Hyperkalemia
Pulmonary oedema
Uraemia
Acidemia

Question 25

Indications of dialysis

Answer 25

Refractory pulmonary oedema (fluid bluids up in lungs)
Persistent hyperkalaemia (no difference after insulin and dextrose)
Severe metabolic acidosis
Uraemic encephalopathy or pericarditis
Drug overdose – BLAST (Barbiturate, 
Lithium, 
Alcohol-ethylene glycol, 
Salicylate, 
Theophylline)

Question 26

Prognosis of AKI - put these in order from highest prognosis to lowest:
Medical illness, Obstetric/poisioning, Trauma/surgery, Burns

Answer 26

Burns, Trauma/surgery, Medical illness, Obstetric/poisioning

Question 27

What % of AKI are preventable

Answer 27

30%

Question 28

Prevention of AKI

Answer 28

Drugs

Diagnose early and give IV fluids to keep hydrated