Intercostal Nerve Block
If you suffer from chronic pain in your chest wall or upper abdomen that has failed to improve with time and medication, you may benefit from this amazing treatment option.
What is an Intercostal Nerve Block?
An intercostal nerve block is highly specialized procedure used to treat pain in the chest and upper abdomen. By targeting the small intercostal nerves that travel under each the ribs, a variety of pain syndromes can be effectively treated without medication.
The procedure involves placing a small amount of local anesthetic, cortisone, dehydrated alcohol, or any other number or specialized medications in the space between the ribs – thus blocking the pain signals in the region and decreasing any local inflammation.
An intercostal nerve block is unique in that it is not only useful in treating pain, but in determining the source of the pain as well. If a patient feels relief after the diagnostic intercostal block, the physician is able to identify the pain generator and the route the pain signals are taking.
Conditions that can be effectively treated with an intercostal nerve block include:
Post-thoracotomy Syndrome (pain after chest surgery)
Post-Herpetic Neuralgia (PHN)
Shingles pain and acute herpes zoster
Acute pain emergencies
Chronic post-mastectomy pain
Neuropathic chest and upper abdominal pain
The intercostal nerves are a pathway for transmitting pain in the chest and upper abdomen. The nerves are easily accessible; the benefits of targeting them to ameliorate pain are unquestioned. An intercostal nerve block is a minimally invasive procedure with documented success in treating neuropathic pain, metastatic bone pain, and even pain due to trauma. In cases where the blocks are successful, the procedure can be repeated periodically to manage recurring pain.
An intercostal nerve block is typically performed one of two ways, 1) as a diagnostic block or 2) a therapeutic block. In most cases (especially in nonmalignant pain syndromes), you physician will choose to perform a diagnostic block first.
- Diagnostic Block – A small amount of local anesthetic, like Lidocaine or Bupivacaine, will be injected to see how the pain responds to a block of the intercostal nerve.
- Therapeutic Block – If the diagnostic block shows a temporary decrease in pain and symptoms, a therapeutic block will follow with the administration of a neurolytic agent such as dehydrated alcohol or phenol.
More Details - Intercostal Nerve Block
The intercostal nerves arise from the anterior division of the thoracic paravertebral nerve. They are considered to be primary rami of the T1 through T12 thoracic nerves. An intercostal nerve has 4 major branches:
- Unmyelinated postganglionic fibers from the grey communicating rami – these connect and communicate with the sympathetic chain.
- Posterior cutaneous branch – innervate the muscles and skin of the paraspinal region.
- Lateral cutaneous branch – arises in the anterior axillary line and provides the majority of the cutaneous innervation to the chest and abdominal wall.
- Anterior cutaneous branch – innervates the chest and abdominal wall from the midline of the chest.
These nerves rarely cross the midline and tend to only provide innervation on the same side of the body from which they arise.
Once the nerves branch off from the spinal cord and their corresponding divisions in the paravertebral space, the intercostal nerves will enter into the intercostal space, lying between the pleura and the innermost intercostal muscle. The nerves will lie under the rib, just below the intercostal blood vessels. As the nerve courses around, along the under-portion of the rib, it will move slightly more superficially to now lie in front of the innermost intercostal and below the inner intercostal.
Each intercostal nerve has a fairly well defined region of sensation it is responsible for, with a small amount of overlap with the nerve located at the rib above and below it. For example, the T3 and T4 intercostal nerves are responsible for sensation along the nipple line while T10 is responsible for the umbilicus.
The diagnostic portion of the procedure is typically performed twice to make certain an intercostal nerve is indeed a source of pain. Once this has been confirmed, the neurolysis is a one time procedure that will offer pain relief for several months at a time.
The relief from a positive diagnostic block is almost immediate, as the effects of the local anesthetic are typically felt before a patient even leaves the office. The medication will wear off in just a few hours and the pain will return – THIS IS NORMAL. This lets your doctor know the intercostal nerves are transmitting pain, and that the pain hasn’t moved into the Central Nervous System yet – making the intercostals a good target for the therapeutic procedure.
The relief from the therapeutic procedure may take a few days to reach maximum effect. There may be some soreness in the area after the procedure – don’t be alarmed, this will typically resolve on its own.
Is an Intercostal Nerve Block Right for Me?
If you suffer from chest wall pain or upper abdomen pain that has failed to improve with conservative treatment and medication, this procedure may be an option for you. An intercostal nerve block should be performed under the strict supervision of a board-certified pain management specialist.
Contact the Ainsworth Institute to set up an initial evaluation to find out if you are a candidate.
Procedure - Patient Details
An intercostal block is an outpatient procedure. Patients tend to tolerate the procedure extremely well with only local anesthetic. As this is a procedure that requires precision, IV sedation may be offered to provide additional comfort. The block can be performed in multiple positions: prone, lying on the side or even sitting up.
Because accuracy is of the utmost importance in performing a successful intercostal block, your physician will likely rely upon some form of guidance to properly position the need as close as possible to the intercostal nerve (fluoroscopy or ultrasound). Ultrasound has been shown to provide greater accuracy with needle placement while decreasing the likelihood of adverse outcomes due to the ability to visualize the needle and its proximity to adjacent vital structures in real time.
Before starting the procedure, you will be hooked up to monitors to track your vital signs. Once you are properly positioned, your doctor will thoroughly clean and sterilize your skin to minimize the risk of infection. At this point a sterile ultrasound will be applied to your skin – this will be moved around slightly until the ribs and intercostal structures come into view. Once the targets are identified on the monitor, a small amount of local anesthetic will be injected in the skin and the underlying tissue. After this, a small, thin needle will be advanced, under direct visualization of the ultrasound, into the intercostal space with the tip positioned as close as possible to the intercostal nerve.
Once the needle is in the proper position, a small amount of local anesthetic (with the possible addition of cortisone or a neurolytic agent) will be injected and the procedure is complete. After a successful block, you will begin to feel pain relief in a matter of minutes to hours.
Depending on the number nerves being injected, the procedure can be completed in as little as 10 to 15 minutes. Once the procedure is complete, a small Band-Aid will be placed and you will be transferred to the recovery area for monitoring.
An intercostal nerve block is a safe procedure when performed in the hands of an experienced physician. The use of ultrasound guidance can greatly reduce the likelihood of an adverse event, but not eliminate it completely. The most feared complication is a pneumothorax – this will occur if the needle is advanced too far and punctures the pleural sac around the lungs. The incidence of a pneumothorax can range anywhere from 0.09% to 8.7%. By using ultrasound guidance, your physician can monitor the tip of the needle in real time and maintain safe distance from the pleura. Moreover, should a pneumothorax occur, ultrasound has 100% sensitivity and specificity in immediately identifying it. Other potential complications include, bleeding, infection, liver subscapular hematoma, nerve damage, and allergic reaction to the medications being used.
Evidence of Performance
Intercostal nerve blocks were first introduced in 1909 when surgeons used cocaine to block the chest wall and upper abdomen prior to surgery. As regional anesthesia evolved, the procedure became more technical targeting specific intercostal nerves for blockade with more concentrated amounts of local anesthetic (procaine) to obtain surgical anesthesia. In 1922, Labat described the intercostal block and the technique, which has remained relatively unchanged to this day.
Pain management doctors consider the intercostal nerve block the treatment of choice for a variety of pain syndromes involving the chest wall and abdomen, due to its ease to perform and predictability of response.
The Ainsworth Institute is Here to Help
If you are suffering from chest wall or upper abdominal pain, and believe it may be due to PHN, shingles, post-thoracotomy syndrome, post-mastectomy syndrome, cancer or a metastatic process, contact the Ainsworth Institute of Pain Management. Meet with once of our board certified pain management specialists to find out if you are a candidate for an intercostal nerve block.
 Kopacz DJ, Thompson GE. Intercostal nerve block: In Waldman SD, editor: Interventional Pain Management, 2nd ed. Philadelphia, Saunders, 2001.
 Narouze, SN: Atlas of Ultrasound-Guided Procedures in Interventional Pain Management. 2nd ed. New York, Spinger, 2010.
 Labat G. Regional Anesthesia: Its Technical and Clinical Application. Philadelphia, Saunders, 1922.