e. Celiac Plexus and Splanchnic Nerve Blocks

What is a celiac and splanchnic nerve block, what is its purpose, and how does it work?

• The celiac plexus is a network of nerves located in the abdomen, just in front of the spinal column, composed of three nerve ganglia.
• The splanchnic nerve chain runs along both sides of the spine, at the level of the lumbar vertebrae, providing nerve supply to upper abdominal organs similar to the celiac plexus.
• A splanchnic nerve block can be applied in all cases where a celiac nerve block is indicated.
• These nerves act as a relay station transmitting messages (such as pain sensation) from various abdominal organs (pancreas, stomach, liver, spleen, adrenal glands, small intestines, and part of the large intestine) to the brain.

For which types of pain are celiac plexus and splanchnic nerve blocks used?

• Severe pain originating from upper abdominal cancers, like those of the stomach and pancreas
• Chronic pancreatitis

What preparations are needed before a celiac plexus or splanchnic nerve block?

• Request a detailed explanation of the procedure from your doctor. Your doctor will require written consent as per legal requirements.
• Inform your doctor about any other medical conditions, medications you are taking, and substances or drugs that cause allergies. Herbal supplements such as vitamin E, glucosamine, garlic, and ginseng may also cause bleeding.
• Consult your doctor about discontinuing all blood thinners except aspirin if necessary.
• Bring all your previous medical test results, MRIs, CT scans, and lab findings to the procedure.
• Wear comfortable clothing and leave accessories like watches, rings, and other jewelry at home.
• Avoid food and water at least 4 hours before the procedure. However, medications for other systemic diseases may be taken with a small amount of water.
• About two hours before the procedure, 500-1000 ml of fluid may be given intravenously to prevent a drop in blood pressure during the block. The procedure is then performed.
• Sedation, a form of light anesthesia, will be applied during the procedure, so you are not allowed to drive home. You should come with an accompanying person. The local anesthetic used can cause temporary weakness and numbness in the legs, preventing you from driving.

How is a celiac or splanchnic nerve block performed, and how long does it take?

• The procedure is performed in an operating room under local anesthesia. Blood pressure, heart rate, and respiration are continuously monitored by an anesthesiologist. The patient is placed face down, the area is sterilized, and the necessary preparations are completed.
• Sedation is administered so the patient does not feel pain and does not remember the procedure.
• Under imaging guidance, the entry site is determined just above the lower back, where the ribs end. Two special needles are then inserted from both sides of the spine. The intervention is performed under radiological imaging to avoid damage to nearby organs and vascular structures.
• To confirm the correct placement of the needles, a contrast dye is injected under imaging guidance, and the needle position is verified. Then, a diluted alcohol solution is injected into the area. The intervention takes about half an hour, and no significant discomfort is felt.

• After the procedure, the patient is observed for several hours before being allowed to go home, with strict bed rest required for the first 24 hours.

Is a celiac or splanchnic nerve block painful?

The patient does not feel pain during the procedure due to sedation. However, back pain that can be alleviated with painkillers may occur for 24-48 hours as the diluted alcohol spreads through the nerve tissue. This pain also subsides later.

What should I expect from a celiac or splanchnic nerve block?

The effectiveness of the treatment varies depending on individual characteristics and the underlying disease causing the pain. It is more effective for cancer pain originating from a single organ, like pancreatic or liver metastasis, but less so for more widespread pain. The effect of the celiac or splanchnic nerve block can be assessed in two ways:

• The pain disappears completely.
• There is a significant reduction in the patient's need for opioid pain medication. Both outcomes are considered successful. Nerves in the body begin a regeneration process after damage, and this varies from patient to patient, usually remaining effective for about six months. The effect of the celiac or splanchnic nerve block is limited to the upper abdominal organs supplied by the nerve. If the disease spreads to other areas, the patient will feel pain from those areas.

When can I return to work after a celiac or splanchnic nerve block?

After a celiac or splanchnic nerve block, patients may experience a drop in blood pressure for several days. Therefore, monitoring of blood pressure and bed rest for a few days is recommended. Afterward, the patient can return to their normal life.

What are the risks and side effects?

The main undesirable effects of a celiac or splanchnic nerve block can be divided into two groups. The first group is related to the medication used and the procedure itself and includes hypotension (low blood pressure), back pain lasting 24-48 hours, and diarrhea mentioned above. Both side effects typically resolve quickly. A very small number of patients may experience prolonged diarrhea.

• The other group of undesirable effects is related to incorrect placement of the needle, which can lead to vascular injury, damage to internal organs such as the kidneys or lungs, and injection of the medication into the membranes surrounding the spinal cord or directly into the spinal cord. When the procedure is performed under radiological guidance by experienced physicians, these complications are very rare.
• Additionally, as with any procedure, there is a risk of bleeding and infection at the site of the procedure, which are rare if proper care is taken. The most significant side effect of the splanchnic nerve block is the needle being directed towards the lung, which can lead to a condition called pneumothorax, where lung ventilation is impaired.
• The celiac or splanchnic nerve block must be performed by pain management specialists who are trained in this area.

Who should not have a celiac or splanchnic nerve block?

 Celiac and splanchnic nerve blocks should not be performed on patients who have metastasis or infection in the area to be treated, or in patients with a generally poor health status.