Caudal Epidural Anesthetic in Dogs

Running along the length of a dog's spine, there is a void that lies between each vertebrae and the spinal cord (enclosed within the various membranes and tissues which support and protect it). This void is referred to as the 'epidural space', and it contains a number of nerves, connective tissues, and blood vessels that help the central nervous system to function optimally. One method of delivering anesthesia to an animal that is in pain or is about to undergo surgery is to inject the anesthetic directly into the epidural space. The rationale behind this is that it will cause the effects of the drug to be much more effective than is achievable with traditional methods of delivering anesthetic (such as injection or gas). The caudal region of the spine is the lower part that connects to the tail. The use of the method on this area is this known as 'caudal epidural anesthetic'.

Before the anesthetic can be administered, the dog must be laid face down on a flat surface in order to provide ease of access to the spinal cord. Next, the vet will have to make sure that the injection site is thoroughly cleaned, in order to remove even the slightest chance of infection, and numbed with an ice pack so that the dog will not feel the needle going in. Once this is done, there are two techniques that the vet can use. Either the needle containing the local anesthetic is directly inserted through the skin and threaded between two of the vertebrae into the epidural space and the anesthetic injected, or a secondary needle (sometimes referred to as a 'hanging drop') is maneuvered into the epidural space and the anesthetic is then drip-fed through it. In either case, it will only take a few seconds before the anesthesia starts to have an effect, allowing the next steps of the treatment to begin.

Caudal epidural anesthetic is very effective, as the chemicals are able to have a direct impact on the central nervous system, instead of having to first be filtered through the bloodstream or respiratory system. The effects of the anesthetic can last for just a few hours to almost an entire day, depending on the type of drugs used. That said, because the epidural procedure only allows for the use of local anesthetics, for more complex or time-consuming operations, a general anesthetic may prove to be more appropriate. This is because they will greatly lessen the chances of the dog either moving during the procedure or becoming distressed. However, elderly dogs may be better suited to the epidural due to the risk of respiratory failure that general anesthetics can sometimes present.

In terms of how long the anesthetic itself will take to wear off, the period is usually measured in hours, though some stiffness and loss of balance may persist for the next few days. It will also be important for owners to keep the injection site as clean as possible for a week or two, to prevent bacteria from taking hold and potentially infecting the spinal region. In the event that the dog has to undergo a significant surgical procedure, it should be remembered that the loss of balance in their hindquarters due to the epidural anesthetic can potentially cause them to re-open their wounds. Thus, it may be wise to keep them as still as possible in the time immediately following the procedure. Generally, the vet will not see fit to book a follow-up appointment to monitor the effects of the anesthesia, though further treatment of the underlying condition may be required.

Most caudal epidural anesthetic procedures will be somewhat more expensive than conventional anesthetic due to the delicacy of the procedure and the degree of skill required to properly execute it. On average, the procedure will fetch a price of just over $100, though complicating factors such as illness and specific injuries may add to this amount. In contrast, a general anesthetic will be more or less comparable in terms of financial cost, though it may not be the best option from a medical standpoint for certain animals.

Although pain management of this type can be very effective, some owners are understandably reluctant to allow their dog to undergo the procedure. One of the main reasons for this is the worry that damage to the spinal cord could occur during the injection. Whilst there is a very slight risk of this happening, it is worth bearing in mind that the epidural space is lined by a tough layer of connective tissues, making it difficult to maneuver the needle in a haphazard way. Additionally, if the procedure is performed by a properly qualified vet, they will be able to negate much of the risk by applying their training.

The main reason for a dog to require a caudal epidural anesthetic is injury to the lower body. This is mainly due to the dog being struck by vehicles, meaning that proper road safety training and introducing measures to prevent the animal from straying away from their owners' property can go a long way towards keeping them healthy. Additionally, joint problems are a commonly cited reason for needing this type of anesthesia. If the condition is non-genetic, such maladies can be avoided if owners ensure that the dog gets the exercise it needs to maintain proper muscular balance in its limbs and a healthy diet that promotes the health of its connective tissues.