• Reference Number: HEY-940/2022
• Departments: Renal Service
• Last Updated: 1 March 2022

Introduction

This leaflet gives you general information about Acute Kidney Injury (AKI). It is not intended to replace the discussion between you and your doctor, but may act as a starting point for discussion.

What is acute kidney injury (AKI)

A major function of the kidneys is to remove waste products and excess fluid from the body. Acute kidney injury occurs when there is damage to the kidneys causing a build-up of waste products and excess fluid in the body that can make people feel unwell.

‘Acute’ is a term used to describe something that has developed over a short time for example over hours or days.

‘Kidney injury’ describes evidence of damage to the kidneys. This may be described to you as a change in your kidney function which is detected through blood tests or a reduction in your urine output.

What causes acute kidney injury?

Most causes of AKI are due to reduced blood flow to the kidneys. This can occur due to dehydration from severe diarrhoea and vomiting or low blood volume from bleeding. If you have sepsis, heart failure or liver failure, the heart may be pumping less blood than normal and this may also cause an effect on the blood flow to your kidneys.

AKI can also be caused by a blockage to the drainage of the kidneys. This will have been diagnosed by an ultrasound scan of the kidneys and drainage system.

The blockage may occur due to:

• An enlarged prostate
• A tumour in the pelvis such as ovarian or bladder tumour
• Kidney stones.

Less commonly, AKI can occur due to a problem with the kidney itself. If this is the case, the healthcare team will provide you with additional specific information.

What are the symptoms of acute kidney injury?

You may not have any symptoms especially in the early stages.

Symptoms of AKI include feeling sick or being sick, drowsiness and passing less urine.  If you start to build up fluid in the body (oedema), this may be in the form of swollen ankles or you may feel breathless due to accumulation of fluid in the lungs.

How is AKI diagnosed?

AKI is diagnosed using a blood test to measure your levels of creatinine. Creatinine is a waste product that is cleared by your kidneys and can accumulate when your kidneys are not working well.

You may also be asked to provide a urine sample and to attend for an ultrasound scan of your kidneys to look for any blockages. Sometimes, further additional tests may be required.

How is acute kidney injury treated?

The treatment you receive will depend on the cause of your AKI.  It may include:

• fluids given either orally or through a drip in your arm
• changes to your regular medication
• a small operation to relieve any blockage if this is found in the kidneys
• specific medicines such as steroids or other medications may be required which your doctors will have discussed with you.
• a period of dialysis treatment using a specialised machine. This may be needed in more severe episodes of AKI to take over the function of the kidneys whilst the underlying cause of the kidney injury is treated.  It can take some time (weeks or months) for the kidneys to improve.

What is the Outlook?

The outlook depends on the cause and severity of your AKI. Most patients improve and become well enough to leave hospital.

If your kidney function does not recover completely, you have developed a condition known as Chronic Kidney Disease (CKD).  Depending on the severity, CKD can have consequences for your long term health. If this is the case, there are more detailed patient information resources that we will share with you.

Anyone who has had an episode of AKI is at a higher risk of it happening again than those who have not.

What happens after discharge?

• You may be asked to have repeat blood tests, urine test and blood pressure by your general practitioner (GP) or practice nurse.
• We will write to your GP with details of your admission including any changes made to your regular medicines.

What can I do to reduce the risk of developing acute kidney injury?

Any illness or situation that leads to dehydration and/or low blood pressure can put you at risk of AKI. It is important that you discuss your condition with a health care professional. This may be your GP or a specialist nurse.

Your doctor may advise you to have temporary stop to certain medications when you are unwell to prevent you from having AKI. This is called a ‘medicine holiday’.

Useful resources

Most of your questions should have been answered by this leaflet, but remember that this is only a starting point for discussion with your doctor. For further reading on Acute Kidney Injury, https://www.thinkkidneys.nhs.uk/aki/ is a useful online resource.

There are also useful online resources for kidney patients that you might find helpful although these mainly focus on patients with permanent or chronic kidney disease, eg the National Kidney Federation on 0800 169 09 36 or www.kidney.org.uk.

Acute Kidney Injury (AKI) discharge plan

Cause of AKI

We have started the following new medicines

We have stopped the following medicines. Please do not start these when you get home unless you receive specific instructions to do so.

“Medication holiday”

If you are unwell with vomiting, diarrhoea, fever, sweats or shaking (unless only minor), stop taking these medications while you are unwell. Restart them when you are well (after 24-48 hours of eating and drinking normally).

We would like you to get a blood test on:

We have arranged hospital follow up on:

You may have questions which we can address in your next hospital appointment, you may write them down here as a reminder:

General Advice and Consent

Most of your questions should have been answered by this leaflet, but remember that this is only a starting point for discussion with the healthcare team.

Consent to treatment

Before any doctor, nurse or therapist examines or treats you, they must seek your consent or permission. In order to make a decision, you need to have information from health professionals about the treatment or investigation which is being offered to you. You should always ask them more questions if you do not understand or if you want more information.

The information you receive should be about your condition, the alternatives available to you, and whether it carries risks as well as the benefits. What is important is that your consent is genuine or valid. That means:

• you must be able to give your consent
• you must be given enough information to enable you to make a decision
• you must be acting under your own free will and not under the strong influence of another person

Information about you

We collect and use your information to provide you with care and treatment. As part of your care, information about you will be shared between members of a healthcare team, some of whom you may not meet. Your information may also be used to help train staff, to check the quality of our care, to manage and plan the health service, and to help with research. Wherever possible we use anonymous data.

We may pass on relevant information to other health organisations that provide you with care. All information is treated as strictly confidential and is not given to anyone who does not need it. If you have any concerns please ask your doctor, or the person caring for you.

Under the General Data Protection Regulation and the Data Protection Act 2018 we are responsible for maintaining the confidentiality of any information we hold about you. For further information visit the following page: Confidential Information about You.

If you or your carer needs information about your health and wellbeing and about your care and treatment in a different format, such as large print, braille or audio, due to disability, impairment or sensory loss, please advise a member of staff and this can be arranged.