HNY Policy and Pathway Repository - York

What is AKI?¹

• This is a loss of kidney function over hours or days
• Low levels of public and professional awareness
• Diagnosis starts with the identification of hypotension and falling urine output during acute illness, and arranging kidney function testing
• Urine should be dipstick tested for blood, leucocytes, protein, nitrites and glucose and remember acute nephritis
• Hydration and safe prescribing are priorities

None provided

Why does it matter?¹

• AKI is associated with 1 in 5 emergency hospital admissions
• Off all people with AKI, 2/3 developed it in the community
• It is associated with increased mortality in short and long term, contributing to 100,000 deaths /yr
• It has poorer health outcomes
• People are more likely to have more CKD after AKI 
• It is associated with longer lengths of hospital stay and more need for HDU and ICU care
• It is associated with increased RRT

Why does it happen?¹

• Any condition associated with reduced perfusion of the kidney can be associated with AKI when the person is exposed to an acute illness
• AKI is more likely when the kidneys are more susceptible to damage for example older people with complex co-morbidity, existing CKD and multiple medications

Potential causes of AKI¹

Exposures (mostly reversible)	Susceptibilities (mostly irreversible)
Sepsis	Dehydration or volume depletion
Critical illness	Advanced age
Circulatory shock	Female gender
Burns	Black race
Trauma	CKD
Cardiac surgery especially bypass	Chronic heart, lung or liver disease
Major surgery	Diabetes mellitus
Nephrotoxic drugs	Cancer
Radiocontrast agents	Anaemia
Poisonous plants and animals	Hypertension

 

Diagnosis of Acute Kidney Injury¹

AKI Stage	Serum creatinine	Urine output
Stage 1	Increase of more than or equal to 26.5 umol/l or increase of 150-200% from baseline	Less than 0.5ml/kg/h for more than 6 hours
Stage 2	Increase of 200-300% from baseline i.e. 2-3 fold	Less than 0.5ml/kg/h for more than 12 hours
Stage 3	Increase to more than 300% i.e.3 fold increase from baseline or more than 354 umol/l	Less than 0.3ml/kg/h for more than 24 hours. Or anuria for 12 hours

 

Think Kidneys Guide for Primary Care - Who should be assessed in 6 hours?¹

• Potassium >6.0 whatever stage of AKI
• People who are acutely unwell with potassium > 5.5 mmol/l
• People with AKI 2 and 3
• People with underlying heart failure or CKD 4 and 5
• People with poor urine output and fluid intake
• EVERYONE ELSE REVIEW WITIHIN 24 HOURS

Is there hyperkalaemia?¹

• Level of AKI with potassium level determine the response to AKI
• High potassium above 5.5 mmol/lis associated with increased mortality
• Top normal range 5.3mmol/l
• > 5.5-6mmol/l considered mild hyperkalaemia and requires action
• Potassium >5.5mmol/l present in 14% admissions, but 21% Stage 3 CKD and 42% Stage 4 ( Einhorn et al 2009)
• 6-6.5mmol/l is moderately severe and > 6.5mmol/l severe
• All people with potassium >= 6.5 mmol/l irrespective of kidney function should be referred for immediate assessment and treatment
• All people with elevated potassium, acute illness, poor fluid intake and poor urine output should be assessed urgently and considered for admission
• http://www.renal.org/guidelines/joint-guidelines/treatment-ofacute-hyperkalaemia-in-adults 

Factors prompting early assessment and admission¹

• AKI warning stage 3 result
• Any AKI in the context of raised potassium >6.0
• Any AKI and suspected urinary tract obstruction
• Any AKI and suspected intrinsic renal disease
• AKI and underlying CKD or Chronic Heart Failure
• Clinical deterioration irrespective of stage of AKI
• Dehydration not corrected in primary care
• AKI and repeat creatinine genng worse
• Lack of necessary support at home

Medication Review with AKI¹

• The term ‘nephrotoxic‘ should be used with caution as few medications have a direct toxic effect on the kidney
• It may be difficult to restart a drug which a patient thinks is toxic!!
• Some medications may impair kidney function in the context of CKD and hypovolaemia
• Renally excreted medications may accumulate causing increased side effects or toxicity to other organs
• These medications may need dose reduction or suspension or blood dose monitoring

SAD MAN: Drugs to be aware of if patient is hypotensive and unwell¹

• Sulphonylureas
• ACE and ARB
• Diuretics
   
• Meqormin
• Aldosterone antagonists
• NSAID
   
• Gabapentin
• Opiates
• NOAC

See Position Statements on ‘Think Kidneys’ Website¹

• Recommend individualised advice to those at high risk when they are unable to eat and drink
• Cards given by professional NOT help yourself
• NOT RULES but GUIDANCE
• Important to restart medications when patient and kidney function stable because of risk of uncontrolled BP, diabetes and heart failure
• Avoid using ‘Nephrotoxic’ for ACEi and ARB as all antihypertensive medication can exacerbate AKI including diuretics and this may reduce compliance/concordance in the future

 

AKI Alerts to be released into Primary Care on 14 November
York Teaching Hospitals NHS Trust have advised the introduction of reporting of warning stage test results for acute kidney injury arriving in general practice, via GP IT systems, will go live on 14 November 2016.  This is a development from NHS England as a result of a new national algorithm being developed and implemented in pathology labs across the country.
 
The impact for practices is relatively small in that a practice can expect to receive one or two alerts per GP per month in their practice – however, the impact for patients is great.

Being made aware sooner of raised serum creatinine blood results which indicate impaired kidney function, means that acute kidney injury can be detected and treated sooner with an improved outcome for the patient.
 
Recognising this change will present a challenge for practices, Think Kidneys has created a series of resources for primary care.

The development of these resources has been led by GPs in the team and a range of experts to ensure they provide the latest and best information for tackling acute kidney injury. The resources include good practice guidance in publications and easy to use materials.

The nationally agreed algorithm to identify patients with rises in creatinine, which may satisfy the criteria for AKI, has been in place in York Hospital for hospital patients almost the past year. 60% of AKI starts in the community and at the direction of NHS England the alerts are to be rolled out locally on 14 November.

AKI Warning; possible AKI stage 1. There is a rise of more than 26 umol/L within 48hrs or a rise of > 1.5x the baseline. This warning will appear on routine blood results send back to the practice for the requesting doctor to manage.

AKI Warning; possible AKI stage 2. There is a rise in creatinine of more than 2x previous baseline values. This warning will be phoned through to the practice for action.

AKI Warning; possible AKI stage 3. There is a rise in creatinine of more than 3x previous baseline values. This warning will be phoned through to the practice for action.

These warnings do not mean that AKI is necessarily the diagnosis.

The changes should be in the context of acute illness and not in relation to up titration of heart failure medicines or the use of trimethoprim which can give a pseudo AKI due to effects on tubular resorption of creatinine.

What action needs to be taken?

It is important to assess the patient within 6 hours for suspected AKI stages 2 and 3. This may be by telephone if appropriate.

It is also important to be aware of potassium levels when deciding if admission is required.

Think Cause? Think sepsis, hypotension commonly with D and V, obstruction and renal parenchymal disease (rare but significant in young people with haematuria).

Think Medication? Think medications which may exacerbate AKI, NSAID, diuretics, and all antihypertensive medications. Think medications which accumulate and cause harm in AKI such as metformin,opiates, gabapentin and NOAC. Think about any new medications which could have caused the AKI. Is it safe to discontinue these medications until the patient improves?

Think Fluids? Are they thirsty? Are they able to increase their fluid intake? Are they loosing excess fluids? When did they last past urine? Can this be corrected at home?

Think Review? Do they need admission? What is the potassium level? Is the situation improving? Do they have support at home? When do they need some more blood tests?

Think Kidneys? All this information and more is available on the Think Kidneys website. There is patient information for those people considered at high risk of AKI to help them ‘ to keep their kidneys safe’ and for those who may already have had AKI.

There is a free RCGP e-Learning module available for all members of the practice clinical team to use which is based around a clinical case and can be accessed on the RCGP website.

References 

¹Powerpoint Presentation to GPs 14th September 2016 - Griffith, K.E. (2016) ‘New Advice for AKI Detection and Prevention in Primary Care’. Member of Think Kidneys NHS England AKI Project Board: RCGP Representative for Kidney Care.

 

NICE AKI Quality Standards
NICE have published an updated set of quality standards for Acute Kidney Injury (AKI). The standard covers the prevention, detection and management of non traumatic AKI up to the point of renal replacement therapy in all patients with the exception of renal transplant recipients and pregnant women.
 

There is also a new website created specifically on AKI:  https://www.thinkkidneys.nhs.uk/