Intrathecal Drug Delivery
Information for Patients
Background
Intrathecal Drug Delivery (ITDD) or an intrathecal ‘pump’ is a therapeutic tool used for patients with long term, severe pain that has not responded to other treatments.
How does it work?
The ITDD system consists of a tube (catheter) and pump. The pump delivers concentrated amounts of medication into the spinal fluid via a catheter. The pump is the reservoir that houses the medication. The catheter is a thin pliable tube. The pump is typically implanted in the abdomen and the tube buried into the spinal space.
What conditions is it used for?
These procedures are used for a range of painful disorders. The most common disorders that benefit from ITDD are failed back surgery, complex regional pain syndrome, cancer pain, spasticity and other chronic non-malignant pain disorders. Clinically ITDD has been shown to improve pain control and comfort with fewer side effects.
What preparation do I need to make before surgery?
Ideally you want to be in the best medical shape before the surgery. As such the management of your other diseases should be at its optimum. This includes seeing our doctors to optimise the control of any chronic illness (e.g. diabetes, asthma) and seeing your dentist to ensure that your teeth are in their best state.
You should ring the office if you are unwell prior to the procedure, this includes flu like illnesses, dental infections, new medical issues and any skin problems over the area of surgery such as boils, sores or pimples. You will need to fast (solids and fluids) for six hours prior to the procedure, this usually means if your operation is planned in the afternoon fast from six am that morning. If your surgery is in the morning you will have to fast from midnight the night before the procedure.
Anticipate that you will require approximately two to three weeks off work following the implant.
All blood thinning medication should be ceased at least two weeks prior to the surgery this includes aspirin and fish oil. If you are on clopidogrel (plavix or isocover), dabigatran, xarelto or warfarin then you will need to discuss ceasing it with your pain physician and cardiologist.
How is the procedure performed?
Implantation of an ITDD system requires inpatient stay and a general anaesthetic. The procedure is performed in an operating theatre under sterile conditions. The pump is about the size of a hockey puck. It is inserted underneath the skin. An incision will be made below the rib margin and the pump inserted into a pocket of subcutaneous tissue. The catheter tubing is then tunnelled around the abdomen, towards the spine and into the spinal fluid. The catheter is anchored to the spinal ligament and the pump to underlying deep tissue. The wounds are then closed with staples and dressings applied. You will be observed in recovery before being transferred to the ward. Most people are discharged within 48 hours of the procedure.
Post-procedure there will be some pain associated with the surgical wound, this typically lasts 5-7 days. You may require additional analgesia during the recovery period.
What are the risks of the procedure?
Unfortunately, no procedure is without risk. There is a potential risk of the following complications:
- Partial response to the procedure
- Infection
- Nerve and spinal injury
- Risk of haemorrhage/bleeding
- Exacerbation of pain
- CSF leak/postural headache
- Catheter failure
- Pump failure
- Withdrawal
- Overdose of drug
- Seroma
- Granuloma formation (scar tissue around the tubing, this can rarely lead to nerve and spinal cord injury)
Generally, in any patient receiving long term opioid (morphine) therapy long term side effects can occur. These include constipation, hormonal suppression and cognitive (thinking) impairment.
Are there any situations where it cannot be used?
Generally ITDD should not be used in patients who:
- Have clotting or bleeding disorders and/or blood thinning medications (warfarin, heparin, clopidogrel). Medications such as these will have to ceased prior to the operation
- If you are allergic to any of the medications to be injected
- Pregnancy
- Active infection
Precautions:
When your pump is inserted you should take care with the following:
- MRI – the pump needs to turned off by a technician or doctor prior to this, it will need to be turned back on after the procedure.
- Ultrasound/Lithotripsy/diathermy: these should not be performed over the site of the pump
- Anti-theft sensors/security doors: Your pump may set off sensory & alarms! Always carry your Implanted Device Identification card. Note when flying the device will be detected at airport security gates
Once you have the implant
For the first six weeks of the ITDD you can expect to have some post operative discomfort around the site of surgery and implanted pump. You may need to have the settings of the ITDD adjusted until satisfactory pain relief is achieved.
If you have an ITDD then during the initial six weeks it is recommended that you:
- Avoid excessive bending & twisting
- Limit lifting to a maximum of five kilograms
- Avoid contact sport and other high intensity activity
Living with an intrathecal pump
A pump requires lifelong maintenance and support
- You must schedule regular reviews with your Pain Physician
- Attend clinic for regular intrathecal pump refills. Typically this is every 3-4 months and can only be completed by qualified personnel with appropriate equipment.
Always carry your Implanted Device Identification card. Notify health care workers before any tests, procedures or medication changes. Long term it is sensible to purchase a wrist band/medical alert bracelet.
- Additional opioid medication should NOT be taken unless under the direct supervision of your Pain Physician or Local Medical Officer. There is a risk of overdose.
Pump refills can be completed at Greenslopes Private Hospital in a weekly outpatient clinic on a Tuesday or Thursday.