Eellan Sivanesan, MD, director of the Department of Neuromodulation – Pain Medicine and assistant professor of anesthesiology and critical care medicine, provides information about how intrathecal pumps work and what patients can expect if their doctor recommends this method of pain or spasticity management.
What is a Pain Pump?
A pain pump is a small device, implanted with surgery, that allows direct delivery of drugs to the spinal cord and nerves. It consists of several parts, including a pump and reservoir that are placed in the tummy (abdomen) and a catheter that is placed in the intrathecal space of the spinal cord.
The intrathecal space (sometimes called the subarachnoid space) is the area between the spinal cord and the thin, strong membranes that surround and protect it. The intrathecal space contains the cerebrospinal fluid that bathes the spinal cord. Infusing medication directly into this area allows it to reach the spinal cord and nerves, where it can control the pain or abnormal muscle contractions that lead to spasticity.
Because the intrathecal pump delivers medication directly to this area, powerful relief can be achieved at a much lower dose (less than 1%) than what is found in pills or injections, which dilute as they pass through the body in the digestive or intestinal tract. bloodstream . Using a pump can also reduce the side effects of medications that are common with long-term pill use.
In two studies of patients with cancer-related aches and pain from AIDS, researchers found that intrathecal pumps provided better pain control and more manageable side effects than traditional oral pills.
How does a pain pump work?
The parts of the intrathecal pump are placed in your body through a surgical procedure. There are different parts:
- A thin, flexible tube called a catheter is inserted into the intrathecal space surrounding the spinal cord.
- A extension catheter attaches to the catheter in the intrathecal space and goes around the trunk.
- The extension catheter is attached to the pump, a round device that is about 1 inch thick and 3 inches wide. The pump is implanted under the skin of the tummy (abdomen). Your surgeon will program the pump to deliver a metered dose of medication directly into the intrathecal space at regular intervals.
- Inside the pump is a hollow, refillable reservoir that holds the medication. When the reservoir is empty, it can be refilled with a needle.
- A personal therapy manager (PTM) device helps you give yourself an extra dose if you need it. The doctor will pre-set the PTM with the correct dosage so that you can safely use it alone. The PTM typically runs on two AA batteries: Make sure you have fresh batteries in the unit so it’s ready to use if and when you need it.
What drugs are used in an intrathecal pump?
An intrathecal pump can be used with opioid pain relievers, anesthetics (numbing drugs), or baclofen (a drug used to treat muscle contractions and reduce spasticity). Other commonly used drugs include pain relievers such as clonidine and ziconotide.
Can a pain pump be removed?
Yes: If you no longer need or want the pump, or if there is a mechanical problem, it can be removed.
Conditions treated with an intrathecal pump
A pain pump may be recommended to address the following:
- Back or neck pain, including compression fractures, disc pain, spinal stenosis, or spondylosis.
- Pain that lingers after previous surgical procedures
- Abdominal or pelvic pain
- Extremity pain
- Complex regional pain syndrome
- Trunk pain, including postherpetic neuralgia (chronic pain that persists after a shingles infection)
- Cancer pain, which stems from the cancer itself or treatments such as chemotherapy
- Peripheral nerve damage pain
- Neuropathic pain
- Spasticity (muscle stiffening) due to stroke, multiple sclerosis, cerebral palsy, or brain or spinal cord injury
- More rarely, other refractory (severe) chronic pain conditions, when more conservative pain therapies have failed
Who qualifies for an intrathecal pump?
A pump may be appropriate for someone who is experiencing severe, long-lasting pain or spasticity that has not been relieved by other approaches, such as pills, physical therapy, or relaxation techniques.
A pain specialist will help you decide if it’s a good option by asking questions about your pain, what makes it better or worse, what you’ve tried in the past, and the impact of the pain on your life and well-being.
In general, an intrathecal pump is most recommended for people who:
- Other pain management methods have been tried, including multiple opioid pain medications, physical therapy, relaxation techniques, and others
- Needing medication for pain or spasticity around the clock
- Expect to live longer than six months
- You do not have a substance use disorder, increased intracranial pressure, or certain psychiatric conditions that can make pain management difficult
Intrathecal pump test
Because individuals’ response to medication varies, the intrathecal pump may not work for everyone. To help you and your doctor decide, you may have a trial of medications administered into the intrathecal area to see if it provides relief. Trials are rarely performed for chronic pain, but are more common with pumps to treat spasticity. Pumps for cancer pain are placed without a trial phase in most cases.
There are several ways to perform the test:
- One dose of medication placed in the intrathecal space with a lumbar puncture.
- Multiple dosesvia lumbar puncture with or without a catheter, are placed in the intrathecal space.
- A continuous testingwhere a catheter is placed in the intrathecal space and connected to a pump not implanted in the body.
The trial can also help the doctor figure out the best place to implant the catheter and the medication that will work best to relieve your symptoms.
Pain pump surgery
The procedure is performed by an interventional pain specialist and takes three or four hours.
Preparation for the pain pump procedure
- After you and your pain specialist determine that a pain pump is a good option for you, your surgery will be scheduled.
- Before the procedure, you may have some tests, such as a blood test and an EKG to make sure you are healthy enough to have the surgery.
- You will be advised not to eat or drink anything after midnight before your operation.
- Ask your doctor if and how you should take your medications the morning of your procedure.
Pain pump implantation: what happens
- You will have an IV in your arm and will be given general anesthesia to keep you asleep during the implant surgery.
- The surgical team will shave the areas on your back and abdomen where the parts of the device will be implanted.
- The surgeon makes a small incision (cut) in the skin of the low back over the spine, exposing the bone around the part of the spinal cord where the catheter goes.
- The surgeon inserts the catheter into the intrathecal space and places sutures to hold it in place.
- The surgeon creates a tunnel around your torso and places the extension catheter under the skin. Like an extension cord, the extension catheter connects the catheter in the intrathecal space to the pump, which is placed under the skin of your abdomen.
- After forming a pocket under the skin of the abdomen, the surgeon places the disc-shaped pump in the pocket and attaches the extension catheter to it.
- The surgeon sometimes puts the pump in place by suturing it to the fascia, a layer of strong connective tissue that covers the abdominal muscles.
- The team closes the two incisions and connects the areas.
Recovery from intrathecal pump surgery
- After a few hours of observation in the recovery room to make sure your heart rate and blood pressure have returned to normal, you will usually be discharged home.
- Your intrathecal pump will be programmed to deliver the optimal drug regularly throughout the day and night, and then you can go home.
- You may experience swelling or pain at one or both incision sites for a few days. Your doctor will make sure you have instructions on when to remove the bandage and douche and how to care for the incisions while they heal.
- You will be given a belly band to wear over the pump site. This promotes good healing after surgery.
- After a week or two, you will return to the surgeon who implanted the pump. He or she will make sure your incisions heal properly.
For four to six weeks after surgery:
- Do not lift anything heavy (10 pounds or more).
- Don’t twist your torso or bend at the waist to pick something up off the floor.
- Avoid extreme temperatures such as hot tubs, ice baths or saunas.
Side effects and complications of the intrathecal pump
Having a pain and/or spasticity pump is generally safe. Side effects and complications are rare, but can include:
- Leakage of cerebrospinal fluid
- Mechanical problems with the pump or shifting of the device after strenuous exercise, which may require repositioning or replacement
Living with an intrathecal pump
Having a pain pump on and working should relieve your pain and help you regain some of your normal activities. Here you will find answers to frequently asked questions:
How is an intrathecal pump refilled?
Every one to three months you will return to your pain doctor to have the pump refilled with medication. Sometimes these fillings can be performed at home by a skilled nursing service under the guidance of a doctor. The provider will remove any remaining medicine from the reservoir of the pump with a needle and then inject new medicine into the reservoir.
What happens if my pain or spasticity gets worse?
If your pain level increases, your doctor may be able to adjust the dose after verifying that the pump is working properly. If your pain or spasticity continues to get worse, call your doctor, who can reprogram the pump in his or her office. You may be prescribed medication in pill form to have on hand when the pain and/or spasticity gets worse.
Does my intrathecal pump set off metal detectors?
Yes. You will be given a card indicating that you have an implanted device in your body. Always keep it with you.
How long does an intrathecal pump last?
The pump’s battery is designed to last five to seven years. When the battery begins to run low, your doctor will be alerted when you need to refill it. There will be time to replace the pain pump before it stops working.
Can I get an MRI with an intrathecal pump?
If you are having an MRI test, let the doctor ordering the test and the technologist performing the MRI know that a pain pump has been implanted. While the imaging is taking place, the pain pump will stop working and you may be alerted with an alarm. It will start working again after the test is over; however, a device representative or physician should verify that the pump is working properly after the MRI.
When should I call my doctor?
Call your doctor if the pump beeps or you experience any of the following symptoms:
- Increasing pain
- Redness or swelling near the pump
- Increasing nausea, tiredness, weakness, dizziness or numbness