1. Renal Pharmacy Beginners Guide - Lecture 5
Acute Kidney Injury
Renal Pharmacy Beginners Guide - Lecture 5

2. Objectives Define AKI Identify risk factors for AKI
By the end of this session you should be able to:
Define AKI
Identify risk factors for AKI
Correctly stage an AKI based on creatinine levels or urine output
Describe the signs and symptoms associated with AKI
Demonstrate the management of AKI
Apply safe and appropriate medicines management for patients with an AKI

3. Definition of AKI
A significant deterioration in renal function occurring over hours or days, clinically manifesting as an abrupt and sustained rise in serum urea and creatinine
Oxford handbook of Clinical Medicine 8th edition
AKI can result in failure to maintain fluid balance, electrolyte levels and acid-base homeostasis
AKI now replaces the term acute renal failure (ARF)

4. Epidemiology
Wang et al, 2012
Think Kidneys National AKI Programme

5. Risk factors for AKI NICE CG169 August 2013
Chronic kidney disease
Heart failure
Liver disease
Diabetes
History of acute kidney injury
Oliguria
Neurological or cognitive impairment or disability, which may limit access to water
Surgery
Dehydration / hypovolaemia
Use of drugs with nephrotoxic potential
Use of iodinated contrast agents within the past week
Symptoms or history of urological obstruction
Sepsis
Deteriorating early warning scores
Age 65 years or over
Oliguria (urine output less than 0.5 ml/kg/hour)

6. Signs and symptoms of AKI
Signs and symptoms will depend on cause, but may include:
Reduced urine output or anuria
Change to urine appearance
Change in urine smell
Swelling in legs, ankles and around eyes
Fatigue or tiredness
Shortness of breath
Nausea and vomiting
Abdominal pain
Dehydration and thirst
Seizure or coma in severe cases
Chest pain or pressure
Confusion and drowsiness
AKI may also be asymptomatic and will need a blood test to confirm diagnosis
Think Kidneys
National Kidney Foundation

7. Differences between AKI and CKD
Acute kidney injury
Chronic kidney disease
Unwell
May seem well for level of function
Good colour
Hypertensive
No skin pigmentation
Skin pigmentation
Normal haemoglobin
Clinically anaemic
Normal kidney size
Bone disease
Normal bone x-rays

8. Staging of AKI
AKI can be staged based on severity. Increasing severity of AKI correlates with higher incidence of poor outcomes1 
Staging is based on either
Creatinine levels from a blood sample OR
Urine output (amount of urine produced in a specified time)
Think Kidneys

9. Staging of AKI
KDIGO Criteria (kidney disease: improving global outcomes)

10. Consequences of AKI
Failure to maintain fluid, electrolyte and acid- base homeostasis can lead to:
Fluid accumulation
Toxin accumulation
Hyperkalaemia
Altered pH levels – metabolic acidosis
Chronic kidney disease
End stage kidney disease
Multi-organ failure
Clinical Knowledge Summaries – AKI

11. Identify cause of AKI Hypoperfusion/ hypovolaemia Hypotension
Obstruction
Sepsis
Rhabdomyolysis
Toxins
Medication
Acute trauma
Liver decompensation
Heart failure

12. Classification of AKI
The causes of AKI can be divided into three categories, although more than one cause is often present
CPPE – Acute kidney injury

13. Pre-renal AKI
Hypovolaemia/ volume depletion – excessive diuresis, haemorrhage (shock), burns, gastrointestinal losses
Reduced cardiac output – congestive cardiac failure, acute MI, sepsis, liver failure
Obstruction of renal arteries – renal thrombosis, renal artery stenosis
Medication – causing reduction of blood pressure, circulating volume or renal blood flow e.g. ACEi, ARBs, NSAIDs or loop diuretics

14. Post-renal AKI
Obstruction to urine outflow from the collecting ducts in the kidney down to the urethra
Deposition of crystals in the tubules e.g. uric acid, sulphonamides, aciclovir, cisplatin
Renal stones in the ureter or bladder
Tumour, either within the tract or pressing on it from another pelvic organ e.g. prostate hypertrophy, bladder cancer, bowel cancer

15. Intra-renal/ Intrinsic/ Renal AKI
Vascular – vasculitis, thrombosis, emboli, dissection
Glomerular – glomerulonephritis
Tubular – ischemia, rhabdomyolysis, myeloma, medication with nephrotoxic potential
Interstitial – interstitial nephritis, lymphoma

16. Management of an AKI No specific drug therapy to manage AKI
Early identification is key
Management is based on identifying and treating potential causes
Example
Pre-renal AKI (caused by hypotension & hypovolaemia)
Restore circulating blood volume with appropriate fluid therapy
Monitor electrolyte balance
Monitor blood pressure

17. General principles of AKI management
Check blood pressure
Check urine output
Daily U&Es
Assess risk factors for AKI
Consider if any risk factors are modifiable
Identify cause of AKI
Assess hydration status
Review medication

18. Medicines optimisation in AKI
NICE Seek advice from a pharmacist about optimising medicines and drug dosing in adults, children and young people with or at risk of acute kidney injury.
Patients who are highlighted as having an AKI; either community or hospital acquired, require a review of their medication in order to1:
Eliminate the potential cause/ risk/ contributory factor for AKI
Avoid inappropriate combinations of medications in the context of AKI
Reduce adverse effects
Ensure prescribed doses are appropriate for the patient’s renal function
Ensure all prescribed medications are clinically appropriate for the patient in view of their AKI and co-morbidities
(1) Think Kidneys
(2) NICE 2013

19. Pharmaceutical input for patients with AKI
Identify potential drug causes of AKI
Review medications and ensure medicines are appropriately withheld/ stopped and suggest suitable alternatives
Advise on the use of fluids if required in the management of AKI
Clinical Pharmacist, 2012, vol 2, p

20. Pharmaceutical input for patients with AKI
Provide recommendations around fluid restriction and minimum volumes of drugs used in fluid- overloaded patients
Fluid balance chart – paper or electronic
Advise prescribers about drug dosing in AKI
Counsel patients regarding medication changes
Clinical Pharmacist, 2012, vol 2, p

21. Medications optimisation
Before holding or stopping any medication, review the indication for the medication, review renal function, co-morbidities, blood pressure, other medications for similar indications, discuss with medical team if necessary
Is the patient on any medication that should be stopped or avoided?
ACE inhibitors
ARBs
NSAIDs
Diuretics
Metformin
Aminoglycosides
Contrast media

22. Guidelines for medicines optimisation in patients with AKI
Click on the Think Kidneys logo to view the document

23. Think Kidneys resources

24. Communication to primary care
When a patient is identified as having an AKI in secondary care, the following information should be passed to primary care health care professionals
Stage of AKI
Information regarding medication changes
Follow up requirements (which bloods to be done and when, restarting medications that have been stopped)

25. Summary
AKI is serious and can have a detrimental impact on patients. Delayed recognition can result in permanent renal impairment and even death.
Awareness of risk factors for AKI and early identification is key.
Pharmacists can play an important part in the management of patients with an AKI by reviewing renal function, performing medicines optimisation and raising awareness of AKI amongst patients and other healthcare professionals.

26. Further reading
NICE guidelines injury-prevention-detection-and-management-pdf
Renal association guidelines
Think Kidneys -

27. Thank you