An epidural is a type of anesthesia which is of the regional type and it involves injecting drugs into the patient with the help of a catheter which is inserted in the epidural area. The end result of an epidural is both analgesia (pain loss) and anesthesia (the loss of sensation) and it does it by not allowing nerve signals to be transmitted in the vicinity of the spinal cord.
The epidural area is a place found in the spinal canal, but not in the dura mater membrane. The dura membrane comes in contact with the arachnoid membrane, which contains cerebrospinal fluid.
The main reason why an epidural is done is for the purpose of obtaining the effect of analgesia. There are a number of different methods which can be used for this purpose and it can be done for different reasons as well. The epidural also has some side effects which can prove good in some cases, like vasodilation is for patients which suffer from peripheral vascular disease. If the epidural is needed for a longer period of time, the patient can stay with the catheter inserted in the epidural area for a couple of days and the effect will be persistent during that time.
The effects of the epidural analgesia might be needed for different reasons. One of them is simply providing relief from pain, something usually done for women in childbirth, since it’s not enough for an operation by itself.
One other function of the epidural is that it can be used as a bonus analgesia effect, besides the general anesthesia which might be used. An epidural can be used this way in surgeries like laparotomies, vascular surgeries, hip replacements and hysterectomies.
Epidurals can also be used for anaesthesia purposes, rather than for analgesia. A higher dose is needed in this case.