The brachial plexus is a group of spinal nerves which begin in the neck, travel through the axilla, or armpit, and into the upper arm. These supply nerves to the shoulder, arm and hand. The brachial plexus block is a form of local anesthesia used for shoulder and arm surgery. This nerve block is administered by injecting anesthetic into the brachial plexus through the armpit.
The first application of the brachial plexus block was pioneered by Dr. William S. Halstad in 1885. Dr. Halstad practiced in New York until becoming a professor of surgery for Johns Hopkins where he helped to develop a number of surgical procedures, including the brachial plexus nerve block, which utilized injections of cocaine. At the time there was a limited selection of drugs available for anesthetic purposes, but as new drugs were developed, cocaine was replaced with safer alternatives.
One of the primary reasons to use a regional anesthesia such as a brachial plexus block is to avoid some of the unpleasant side effects of general anesthesia (GA). GA places a patient into an induced and controlled state of unconsciousness. One of the most popular means is through inhalation, a method that sometimes results in breathing issues due to a temporary paralysis of the throat muscles. To counteract this, a tube is generally inserted in the throat, a process called intubation, which can create soreness. Other side effects include nausea, vomiting, headaches and a longer period of post-operative unconsciousness; in rare cases stroke, heart problems and death may occur.
With a brachial plexus block, intubation is not necessary. The patient is often put into a twilight state with an intravenous (IV) sedative, but does not lose consciousness. This results in a much quicker recovery from anesthesia. The IV sedative also limits the amount of anesthesia required and helps to prevent toxic reactions which may occur if a large amount of local anesthetic is absorbed into the bloodstream. Patients with regional anesthesia are much less likely to experience nausea, headaches, throat damage related to intubation or the rare but more serious effects of a general alternative.
The type of regional anesthetic used depends upon what part of the body is being operated on and how long the surgery will take. The brachial plexus block can be effective for shoulder, arm and hand surgery. The block can be administered with single or multiple injections, or can be maintained continuously through a catheter. Depending upon how it is administered, it can last a few hours for more complex repair work.
If severe pain is expected during the first stages of recovery, a catheter can be left in the site to allow for daily doses of medication. Nerve blocks such as the brachial plexus block can also be used therapeutically to treat chronic pain caused by injury to the nerves in the affected area. In some instances, this allows the patient an opportunity to heal without surgery. In cases where surgery is necessary, the continuous block can relieve pain experienced during post-operative physical therapy.
As with any medical procedure, the brachial plexus block can have negative side effects. In rare cases, nerve damage can occur in the area of the block. If too much anesthesia is absorbed into the bloodstream, toxic reactions may affect breathing, heart beat and blood pressure. Occasionally, infection or soreness may occur at the injection site.