When to Put Your Senior Cat to Sleep in Renal Failure

We would all love to be able to spend countless years with our cats, but sometimes serious health issues mean we may need to say goodbye sooner than we'd hoped. Understanding kidney disease in cats and when to euthanize can be particularly challenging, because of the fluctuating symptoms and the gradual progression of the disease. If your cat has been diagnosed with renal failure, understanding how the disease works and what signs you may see in its end stages can help you to understand if and when you may need to say goodbye to your cat.

Cat lying beside a window
Sometimes serious health issues mean we need to say goodbye to our cats.
credit: Catherine Falls Commercial/Moment/GettyImages

Understanding renal failure

A cat's kidneys perform many essential functions. They help to remove waste from your cat's blood and are responsible for producing urine. The kidneys also help to balance the levels of minerals including potassium and sodium.

When the kidneys cannot efficiently remove toxic waste from a cat's body, the cat is considered to be in renal or kidney insufficiency, which is the first stage of kidney disease. Your cat's kidneys will only be functioning at 25 to 15 percent of their capability. During this time, the kidneys will be having trouble removing toxins and extra water from the cat's blood.

When a cat is experiencing kidney insufficiency, they may have a reduced appetite and lose weight. Cats may drink a large amount of water and urinate excessively. Many pet owners miss these more minor symptoms, only recognizing that the cat has a health issue when the symptoms become more serious as kidney failure progresses.

Stages of kidney failure in cats

When a cat's kidneys are functioning at less than 15 percent of their capacity, that cat is said to be in renal failure. At this point, the kidneys are having trouble removing substances, including waste and minerals, from the blood. The kidneys are also having trouble releasing useful substances into the blood. All of this results in a buildup of waste products in a cat's body. Simultaneously, cats lose water that their bodies could have used. Cats in renal failure often develop high blood pressure and may need medication to lower their blood pressure.

Renal failure progresses in four stages, with the symptoms worsening through each stage. Unfortunately, a cat's suffering gets worse as the disease progresses, and symptoms including blindness, heart failures, seizures, the inability to walk, and incontinence may occur.

Damaged kidneys

If kidneys are suddenly damaged, such as by a cat ingesting antifreeze, the cat goes into acute renal failure, which occurs rapidly across days or weeks. Chronic renal failure is a longer lasting condition that cats can live with for months or even years. Chronic renal failure is incurable and can affect one or both kidneys. Once a cat's kidneys are damaged, either from a sudden event like poisoning or from a longer-term deterioration, the kidneys can rarely recover.

However, renal failure can be managed with special diets, antibiotics, supplementation with potassium and Vitamins B and C, and drugs to lower high blood pressure. Your vet may also administer fluids to fix dehydration and flush toxins out of your cat's body. You can work with your vet to carefully manage your cat and, in most cases, renal failure progresses slowly. Cats can live for several years when their renal failure is well-managed.

Respecting your cat’s wishes

While there may be various ways to prolong your cat's life, your cat may not want to participate in these methods. For instance, some pets may not be bothered by regularly getting intravenous fluids. Your cat, though, may not feel the same way, making fluid sessions events that your cat dreads and fights.

It's important to respect your cat's wishes when it comes to procedures that are regular and repeated. Fluids might keep your cat alive longer, but if he dreads each and every fluid session, you might need to have the hard conversation with yourself about whether it is really worth it to keep him alive. Cats can be very particular, and since you know your cat's personality you will likely be able to tell if treatments are making your cat miserable and are harming him more than they're helping.

Assessing quality of life

The very last stages of renal failure are unpleasant, and many cat owners opt to euthanize their cats before their cats pass away naturally from the disease. Talk with your vet so that you can recognize the signs a cat is dying of kidney failure and so that you can understand what to expect as your cat enters the last stage of renal failure.

As your cat's renal failure progresses, you will need to regularly assess her quality of life. Two of the main qualities you should consider are whether your cat is still seeking out and responding positively to attention, as well as whether she is still eating and drinking on her own. Additionally, consider whether your cat is able to still use the litter box on her own, whether she's started to shrink away from you when you go to pat her, and whether she's undergone any significant behavior changes.

Chances are that you know your cat so well that you'll quickly recognize when her health begins to deteriorate. When considering kidney disease in cats and when to euthanize, you should involve your vet in your decision, but ultimately you are the one who needs to make that final decision.

Making saying goodbye easier

When you're facing the decision to euthanize your cat, knowing what's involved can help. Talk with your vet ahead of time about what the process will be like. Think about your aftercare options now.

Will you bring your cat home to bury his body? Would you like to have your cat cremated? By looking into costs and options ahead of time, you can have a plan in place that can make the end of your cat's life a little bit easier and make some of the hard choices you will have to make a little easier because you have already thought about them.

You may also want to come up with a list of the requirements that you'll use when assessing your cat's quality of life, and identify situations where it will be time to say goodbye. For instance, situations like if your cat loses his sight, is unable to walk, or loses a significant amount of weight could all signal to you that it's time to let your cat go. Identify these situations ahead of time so that you can better assess your cat in the moment without your emotions getting in the way.

The symptoms of renal failure can fluctuate, and bloodwork can give you some insight to what's going on in your cat's body. Ultimately, you will need to weigh the physical symptoms with what your cat's behavior is telling you. While saying goodbye to a cat is heartbreaking, if your cat is in pain and has a poor quality of life, euthanizing him may be the kindest way to end his suffering.