Overview of Lumbar Sympathetic Block
The autonomic nervous system is a part of our body that controls many automatic functions. It has two parts: the sympathetic and parasympathetic systems. A type of treatment called a lumbar sympathetic block can disrupt the sympathetic system’s nerves that go to the lower part of the body. This treatment can help control pain that’s linked to the sympathetic system.
Specifically, a lumbar sympathetic block can be used to treat various painful conditions. These conditions include complex regional pain syndrome (a chronic pain condition that typically affects one limb), phantom limb pain (pain that feels like it’s coming from a body part that’s no longer there), hyperhidrosis (excessive sweating), painful vascular insufficiencies (when the blood vessels can’t supply enough blood), and pain from herpes zoster/shingles (a painful rash caused by a viral infection).
Anatomy and Physiology of Lumbar Sympathetic Block
The sympathetic trunk is a group of nerves that runs from the base of your skull all the way down to the tailbone, or the coccyx. It plays a major role in how your body responds to stress situations, triggering what’s often referred to as the ‘fight or flight’ response. Additionally, it’s key in helping your body maintain a state of balance, or homeostasis, working alongside another part of your nervous system, the parasympathetic system.
This nerve bundle in the lower back area, called the lumbar sympathetic trunk, is located along the front and side of the first through fourth lumbar vertebrae, which are the bones in your lower spine. At these spots, neurons called preganglionic neurons leave the spinal cord and meet up, or ‘synapse’, at a key part of the nervous system, known as the lumbar sympathetic ganglion. Then, other neurons, known as postganglionic neurons, carry signals from this point to specific body areas.
The highest number of these lumbar sympathetic ganglia are found in the second and third lumbar vertebrae, L2 and L3. For this reason, when doctors need to perform a specific procedure to block signals in the lumbar sympathetic system, they usually target the lower part of L2 or the upper part of L3.
Why do People Need Lumbar Sympathetic Block
According to the American Society of Anesthesiologists’ guidelines for managing long-term pain, lumbar sympathetic blocks, a type of pain relief treatment, are recommended for several pain disorders caused by the malfunctioning nervous system.
One such disorder is complex regional pain syndrome, previously known as reflex sympathetic dystrophy. This illness disrupts the central and automatic nervous systems, leading to uncontrolled pain and temperature regulation in the affected limb. This condition often occurs in patients who have an injury to their soft tissue or peripheral nerves in one of their limbs. Signs of this disorder include abnormal blood vessel function, swelling, high sensitivity to pain, and an abnormal response to temperature. The affected limb is often swollen, filled with an excess of watery fluid, and may show changes in the skin as a result of abnormal blood vessel activity.
Another disorder is lower limb painful ischemia or lack of blood supply. The National Institute for Health and Clinical Excellence has found that around 20% of patients with painful ischemia in the lower limbs due to vascular disease cannot have surgery because of the nature of their disease or other health problems. For these patients, lumbar sympathetic blocks can be employed to lessen pain, boost wound healing, and potentially delay or prevent limb amputation. The treatment works by interrupting the nervous system signals to the blood supply of the lower limb, causing the vessels to widen and improve blood flow to the limb.
Phantom limb pain is the perception of pain from a limb that isn’t present. The cause of this is not well understood. However, studies have reported 42% to 78% of amputee patients experience phantom limb pain. Case studies have suggested that lumbar sympathetic blocks can be a safe and effective way to alleviate this type of pain.
Lumbar sympathetic blocks have also been found to provide relief in patients with persistent pain due to intractable diabetic neuropathy, a type of nerve damage most often from diabetes.
Postherpetic neuralgia is lingering pain following a shingles outbreak, and lumbar sympathetic blocks have been shown to improve pain, function, and quality of life in these patients.
This treatment technique may also be employed for excessive sweating (hyperhidrosis), Raynaud’s disease (a condition that causes some areas of your body to feel numb and cool), and cancer-related pain.
When a Person Should Avoid Lumbar Sympathetic Block
There are several circumstances in which certain medical treatments may not be possible:
– If a person is on blood-thinning medication that can’t be stopped, because it could increase the chances of bleeding.
– If a person has a condition that affects their blood clotting process, medical treatments might be more risky.
– If a person is allergic to any of the injected medications, treatments involving such medications should be avoided.
– Uncontrolled diabetes can make it more difficult for the body to recover from treatment.
– If someone has heart disease that is not well-managed, some treatments could be too dangerous.
– Lastly, it is important to remember that it is a patient’s right to refuse treatment if they do not feel comfortable with it.
Equipment used for Lumbar Sympathetic Block
The doctor will need certain equipment to perform the procedure. This includes a mobile C-arm x-ray, which is a flexible x-ray machine that can move around the patient. They will also need special needles called epidural spinal needles. The doctor will wear sterile gloves to keep everything clean and safe. They will use medications and a substance known as “contrast” to help see the areas of the body more clearly on the x-ray.
The doctor will also use sterile drapes and a cleaning solution called betadine to make sure the area is clean. To keep an eye on how the patient is doing during the procedure, the doctor will use a cardiac monitor to check the patient’s heart rate and a pulse oximeter to check the oxygen levels in the patient’s blood.
Who is needed to perform Lumbar Sympathetic Block?
The medical team is usually made up of a nurse or an assistant, a person who operates a special x-ray machine called a fluoroscopic C-arm, and a doctor. These team members each have their own tasks to ensure that everything goes smoothly during your treatment. The nurse or assistant looks after your basic needs, the fluoroscopic C-arm operator makes use of this machine to get a good picture of what’s going on inside your body, while the doctor leads the operation or treatment.
Preparing for Lumbar Sympathetic Block
Before the procedure begins, it’s important for the medical team to take a moment to confirm the patient’s identity, discuss the procedure that will be done, and make sure they have identified the correct part of the patient’s body that will be treated. The patient will then lie down on a table called a fluoroscopy table, on their stomach.
Some doctors may choose to give the patient medicine through an IV, or a needle inserted into the vein, to help them relax during the procedure. Once everything is confirmed and the patient is comfortable, the doctor will identify the target area on the patient’s body. This area will then be thoroughly cleaned with a solution called betadine, which is used to disinfect the skin before medical procedures.
After the cleaning, the area is covered with a sterile fabric to keep it clean. Once the patient has been properly positioned and the skin has been cleaned and covered, the doctor can start the procedure. Remember, all these steps are taken to ensure your safety and the success of the treatment.
How is Lumbar Sympathetic Block performed
Doctors use specific medical equipment to perform certain procedures. In this case, they use something called a fluoroscope’s C-arm imaging projector. This tool helps them have a clear view of your spine, specifically the L2 and L3 vertebrae (bones in the lower back area). They position the machine so that these bones are easily seen and in line. Like using a GPS, they needed real-time images to help guide their actions during the procedure.
Occasionally, they might rely on a more advanced technology, called computed tomography or CT scan, that gives a more detailed image, guiding the procedure more accurately. They adjust the C-arm machine in a way that helps them avoid hitting other structures, such as the transverse process, which is a bony projection off the back of each vertebra. The aim is to insert a needle towards the front part of the L2 or L3 vertebrae.
The doctors numb the area where the needle is to be inserted to make you more comfortable. With the help of the C-arm images, they introduce and move the needle towards its target. This is done delicately, almost walking the needle along the bone until it is in the correct position. They also take careful measures to avoid accidentally puncturing important vessels in front of these bones. They use an image from a different angle to double-check the depth of the needle and ensure that it doesn’t go too deep.
Once the needle is confirmed to be in the correct position and it is confirmed that there is no air, blood, or cerebrospinal fluid (fluid in the spinal canal), a small amount of contrast material is injected. This helps to visually confirm that the placement is correct. Do you know medical contrasts, right? They are kind of dyes that help doctors visualize structures better during medical imaging. This contrast should cover the front part of your vertebra and should be spread evenly from L1 to L3 (bones in your lower back).
Once everything is in order, the doctor then injects the medicine into the area. This medicine could be a local anesthetic, alcohol or botulinum toxin, depending on the situation. Then, the needle is removed, some pressure is applied to stop any possible bleeding, and the area is covered with a bandage.
The best sign that this procedure, known as a lumbar sympathetic block, is successful is a small increase in the temperature of the limb associated with that side of the spine. This might feel warmer than usual. Also, due to increased blood flow to the area, the skin on the side where the medicine was injected could become red. All these are normal reactions showing that the medication is doing its job.
Possible Complications of Lumbar Sympathetic Block
The most common side effects people experience after having an injection are bleeding, bruising, swelling, and soreness where the needle went in. These effects are normally minor and go away on their own within a few hours or days after the procedure. Some people might also feel dizzy, have a headache, or notice temporary numbness and weakness in the leg that was injected.
Although it’s rare, there are also more serious side effects. These include infection; damage to organs, blood vessels, or lymphatic vessels near the injection site; kidney injury; a neurological condition called Horner’s syndrome; or an allergic reaction to the medicine that was injected. These side effects don’t happen often, but they are possible.
Occasionally, patients may experience pain in the front of their thigh after the injection. This is thought to be from damage to certain nerves in the area, the genitofemoral nerve and the lateral femoral cutaneous nerve, which help provide feeling and movement to the thigh.
What Else Should I Know About Lumbar Sympathetic Block?
A lumbar sympathetic block is a medical procedure that can successfully and safely treat certain types of pain. It works well for people who have issues with blood flow in their legs, complex regional pain syndrome, phantom limb pain, postherpetic neuralgia, and other nerve-related pain conditions that haven’t responded to usual treatments. In summary, this procedure is a promising solution to manage pain for the right individuals.
