Fluid therapy for rabbits

Fluid therapy

Fluid therapy can be administered at varying rates and by different channels depending on the circumstances. Rabbits' digestive systems contain intricate systems for secreting and absorbing water and electrolytes. If there is any disruption to these processes, dehydration and electrolyte loss can happen quickly. Restoring blood volume, adjusting plasma pH, glucose, and electrolyte levels are the goals of fluid therapy.

What fluids can be used?

A variety of fluids are used in rabbits, depending upon the situation. These aim to restore the hydration level and blood pressure, and contain electrolytes.

Blood transfusions can be given in cases of excessive blood loss, up to 10% of a rabbit’s circulating blood can be lost with minimal adverse effects, but a loss of 20-25% can result in systemic shock and a blood transfusion may be required.

When is fluid therapy used?

The uses are vast, but fluid therapy may be used in rabbits for:

• Dehydration: fluids can be used to help restore hydration. Rabbits can be dehydrated for a variety of reasons and may not show outwards signs, (such as skin tenting, sunken eyes, dry mucous membranes, etc), so this is not a reliable way to assess hydration in rabbits.
• Anorexia: any rabbit who is not eating is also unlikely to be drinking and as a result the GI tract will slow down and come to a standstill. Giving fluids to rehydrate the stomach contents and GI tract is important to help to restore peristalsis in the GI tract.
• Low blood volume (hypovolaemia): a blood transfusion may be used in this situation, or if this is not available a type of fluid therapy may be used instead.
• During surgery to help support the kidneys and blood pressure: anaesthetic drugs can decrease blood pressure, so fluids are given to ensure blood volume continues to be delivered to vital organs, such as the kidneys.
• Kidney disease: fluids can help to ‘flush’ the kidneys through and remove toxins from the blood when the kidneys are unable to. This palliative care can help to make the rabbit feel better for the short-term.

Fluid therapy forms a vital part of a treatment plan and helps to save lives in many situations.

What are the different ways fluid therapy can be given?

There are several ways in which fluids can be given to rabbits. There are pros and cons for each route. The route will be decided by your vet, based on what is best for your rabbit. Common routes of fluid administration include:

• Oral: this is when fluids are given into the rabbit’s mouth. Some rabbits find this stressful and may not swallow the water. It is also difficult to get large amounts into the rabbit via this route and there is a risk that the rabbit may choke on the fluids if they struggle.
• Subcutaneous: injecting fluids into the subcutaneous layers of the skin (usually around the scruff of the neck) is a common way to give fluids. Large volumes can be given over a short period of time and will be absorbed well. The fluids may not be effectively absorbed in very ill rabbits, and large amounts can be painful, as well as the stress and pain caused by having to keep injecting the rabbit.
• Intravenous: these are fluids given directly into the vein, via a cannula. The cannula can be placed in one of many veins and usually placed while the rabbit is conscious. Intravenous fluids are absorbed quickly even in dehydrated rabbits. One of the advantages is that once the cannula is placed the rabbit will not feel the fluids being given each time.
• Intraosseous: this is usually reserved for very ill rabbits whose circulation is collapsed and it is difficult to place an intravenous cannula. This involves placing a cannula into the bone marrow and is usually performed under anaesthesia or sedation alongside pain relief medication. Often, they are well tolerated, and fluids will be readily absorbed.

Are there any risks?

The advantages of fluid treatment clearly outweigh the dangers in all cases. Because rabbits might choke or aspirate on oral fluids, it's important to never give them too much at once and to wait until they've swallowed the contents of their mouth before giving them more. To reduce the risk, the rabbit should never be lying on its back and should always be positioned in a typical sitting position.

Repeated subcutaneous fluid administration can cause minor pain and fur loss in certain locations, especially if higher quantities are administered.

Fluids administered intravenously or intraosseously carry a risk of cannula-related infection. The veterinary team will thus take great effort to maintain the location as clean as possible, but this risk cannot be completely eliminated.

Will I need to give fluids at home?

Requests for owners to administer hydration treatment at home are uncommon. If your bunny needs fluids, they will probably need to be admitted as an inpatient so that the nurses and veterinarians can provide them with the fluids and other care.

In certain cases, such as when your rabbit requires long-term care due to a kidney condition, administering regular subcutaneous injections of fluid at home may help to slow down the progression of the illness and prolong the rabbit's quality of life. Your veterinarian would show you how to perform this if they asked you to.

Warning Signs

• Lethargy: Rabbits should not become overly lethargic during or after fluid therapy.

• Swelling: Watch for swelling at the injection site. This can indicate subcutaneous fluid accumulation.

• Changes in Behavior: Any sudden changes in behavior should be reported to the veterinarian.

Is it painful?

The majority of fluid treatment options don't hurt. A topical numbing lotion can be applied beforehand to ensure your rabbit won't feel the pain of having a cannula inserted into their vein for intravenous access. The procedure is no more painful than administering an injection. Unless the rabbit is unconscious and in a collapsed position, in which case sedation would be extremely dangerous, an intraosseous cannula must be placed under general anesthesia or sedation. Under these circumstances, the rabbit won't sense the cannula.

Subcutaneous fluid therapy may not be appropriate for very sensitive rabbits or for long-term fluid therapy because it requires repeatedly injecting the rabbit, which can be unpleasant.