INTRATHECAL BACLOFEN THERAPY
Spasticity interferes with many patients' care and / or ability to function. In, many cases, spasticity is adequately managed with oral medication and rehabilitative interventions. But some patients do not respond oral medications, or experience intolerable side effects at effective doses. In the past, neurodestructive procedures offered the only option for reducing moderate to severe spasticity. ITB Therapy (intrathecal Baclofen pump therapy) can help people live more comfortable and participate more fully in daily activities. In clinical literature, patients reported that ITB therapy has helped them to be more independent, allowing them to feel or dress themselves, sit more comfortably, or transfer more easily. In addition, caregivers reported that care is easier with ITB therapy.
Oral medications for spasticity help some people. But because these oral medications circulate throughout the body in the bloodstream, only a small amount actually reaches the site of action at the spinal cord. For people with severe spasticity, the amount of oral medication that reaches the spinal cord is not sufficient, and increasing the dose may increase intolerable side effects, such as lethargy.
ITB therapy is different from oral medications because it delivers a form of the drug Baclofen directly to the fluid around the spinal cord. Baclofen is similar to GABA and works in the spinal cord, promoting muscle relaxation. Because the medication is delivered directly to the site of action without circulating throughout the body, it relieves spasticity with very tiny amounts of medication. This delivery system minimizes side effects. Delivery makes the difference in ITB therapy, which has been shown to be highly effective in people with severe spasticity, including those who have not had good results with oral medications.
Understand ITB therapy
- Identify patients who may not be adequately managed with currents spasticity treatments and may be candidates for ITB therapy
- Assess spasticity during the screening test for ITB therapy
- Document impairments and level of function before and after pump implant
- Rehabilitate patients after pump implant
Treatment options for spasticity Management
Management of spasticity is usually determined by the severity of the symptoms and the efficacy of the current treatment. Treatment of spasticity may begin with noninvasive therapies and, if unsuccessful, move to more interventional therapies. Therapies are often used in conjunction with one another.
Typical rehabilitation interventions that may reduce spasticity include: prolonged stretching positioning, positional movements, weight bearing, cryo-therapy, serial or inhibitory casting, electrical stimulation, vibration of the antagonist, pool therapy, EMG biofeedback, heat and splinting.
Baclofen, Diazepam (valium), Dantrolene sodium (Dantrium), and Tizanidine (zanaflex) are used as muscle relaxant. Some patients respond to oral medication. However, many patients may experience intolerable side effects such as drowsiness, dizziness, weakness and nausea. Other patients fail to receive adequate control of their spasticity, regardless of the dose. Botox is most often used to treat localized spasticity.
ITB therapy is Lioresal® Intrathecal (Baclofen injection), administered by the Medtronic SynchroMed ® Infusion system. It provides an effective, non - destructive, reversible, alternative for pediatric and adult patients with uncontrolled spasticity due to multiple sclerosis, spinal cord injury, cerebral palsy, brain injury or stroke. A convenient screening test administered via lumbar puncture determines whether a patient is a good candidate for ITB therapy.
Benefits of ITB therapy
ITB therapy has been shown in studies of hundreds of people to dramatically reduce severe spasticity associated with cerebral palsy, stroke brain injury, multiple sclerosis and spinal cord injury. The therapy dose not involve the destruction of nerve pathways, is reversible (that is, the system can be removed or turned off at the patient's request), and requires smaller doses than oral medications because the drug is delivered directly to the target site. Most spinal origin spasticity can be maintained on an average of 300 to 800 micrograms per day of Baclofen injection versus 30 to 120 milligrams of oral Baclofen. Most cerebral origin spasticity can be maintained on an average of 90 to 703 micrograms per day of Baclofen injection.
In addition to a reduction in spasticity and spasms, patients may experience substantial secondary benefits as a result of the decreased spasticity.
SYNCHRO MED INFUSION SYSTEM
ITB Therapy is administered by Medtronic's SynchroMed Med ® infusion system, a programmable drug infusion system that consists of an implanted drug pump, intrathecal catheter, and an external computer programmer. The pump is surgically implanted subcutaneously in the intrathecal space of the spine canal. The pump releases prescribed amounts of intrathecal Baclofen according to the instructions provided by the external programmer. The patient's pump can be programmed to deliver a continuous amount of medication over 24 hours, or different doses at various scheduled times of the day. For example, some patients receive higher doses of Baclofen at night to decrease spasms during sleep, lower doses during the day to maintain tone for transfers. The pump releases prescribed amounts of Baclofen injection according to the instructions provided by the external programmer. Clinicians can program the pump to deliver a continuous amount of medication over 24 hours, or different doses at various scheduled times of the day. For example, some patients receive higher doses of Baclofen at night to decrease spasms during sleep and lower doses during the day to allow spasticity if needed for transfers.
Potential Risks of ITB Therapy (Drug, Pump, and Surgery)
ITB Therapy involves the surgical placement of a pump and catheter. As with any surgical procedure, there is the potential for infection. Patients should alert their physician in case of any swelling, redness, or pain near the incision.
Patients may experience symptoms caused by too much drug. Watch for any unusual reactions and alert the patient's physician immediately if any of the following are observed:
- Increased weakness
- Nausea / vomiting
An overdose, though rare, of Baclofen injection may lead to reversible coma and the need for respiratory support. Patients may also experience symptoms caused by too drug, which is usually apparent with a return of spasticity and / or muscle spasms. The physician should be notified of any of these symptoms. A sudden requirement for a large dose escalation suggests a catheter complication / or pump failure. Device - related complications include catheter occlusion, kinking, or dislodgment; component failure; or battery depletion. Corrective action may include replacement of the pump and / or catheter.
Candidates for ITB Therapy
Patients who are hypersensitive to oral Baclofen are not candidates for ITB Therapy. (Hypersensitivity is a severe adverse or allergic reaction to Baclofen not a side effect such as drowsiness.) Patients who become drowsy on oral Baclofen may tolerate ITB Therapy without side effects. Patients with severe spasticity due to multiple sclerosis, spinal cord injury cerebral palsy, brain injury, or stroke may be considered for ITB Therapy. Candidates cover a broad range of functional levels, from ambulatory to total dependence for all activities of daily living (ADL).
These patient selection guidelines are recommendations for possible ITB Therapy candidates with severe spinal and cerebral origin spasticity:
- Patients whose spasticity and / or spasms interfere with function or daily activities.
- Patients whose spasticity and / or spasms interfere with care or positioning.
- Spinal origin patients whose oral medications are ineffective or cause intolerable side effects.
- Patients with pain due to spasticity.
- Patients at least 4 years old with sufficient body size tom support the pump.
- Patients who need varying degrees of tone throughout the day for function or activities of daily living.
Patients with spasticity due to traumatic brain should wait at least one year after the injury before consideration of long - term intrathecal Baclofen therapy.
Ideally physical, occupational, and speech therapists thoroughly assess the patient's physical status and functional abilities before the screening test. The baseline assessment identifies the patient's level of impairment, function and care so that changes during the screening test after implant may be documented objectively Baseline functional assessments should include speech, fine gross and oral motor skills, bed mobility, transitions, gait, wheelchair locomotion, and balance, as applicable. In addition, range of motion, strength, spasticity and other movement disorders should be evaluated. If the patient is dependent for care, an interview with the caregiver to establish the amount of time and effort involved in patient care is recommended. Therapists may also aid in goal setting (see section below) for each patient regarding spasticity reduction. Videotaping a patient is often helpful.
Realistic goal setting is a key to satisfaction with ITB Therapy. Depending on the level of ability, a patient may be able to accomplish certain goals with the help of ITB Therapy. It is important to understand that this therapy cannot give the patient any abilities that they did not already have, but it may reduce the spasticity that may be preventing the patient from using existing abilities. Treatment goals vary considerably. The rehabilitation team assesses the patient to determine whether function or ease of care would improve with reduced spasticity. An important consideration is whether the goals of both the patient and family members are congruent with the gains likely to be obtained by reduced spasticity. For patients expecting functional gains may relate to increased independence and reduction of pain. Goals for other patients may include: improved ease of care, comfort positioning, and prevention of further contractures. For patients dependent on other for their care, ITB Therapy can make a significant difference in quality of life, for both patient and the caregiver.
Below is a list of tools that may be used as baseline assessments:
- Modified Ashworth Scales for spasticity
- Spasm Scale to record frequency of spasms
- Pain scale, goniometry to document range of motion, myometry for strength or spasticity , manual muscle testing, or functional strength assessments
- Gross Motor Function Measure (GMFM) to assess functional limitation in gross motor skills for children
- Pediatric Evaluation of Disability Inventory (PEDI) or the Functional Independence Measure for children (WeeFIM) to assess activities of daily living in the pediatric population
- Function Independence Measure (FIM)and Timed " UP and GO" Test to measure in an adult population
- SF-36 to measure quality of life
- Canadian Occupational performance Measure to set a goal. It is an individualized outcome measure.
The Screening Test
Individuals who have been identified as candidates for ITB Therapy should first be given a screening test before proceeding to pump implant. The screening test verifies that the patient's body will respond to ITB Therapy. The examiner, usually a physiatrist or physical therapist, should assess the patient immediately before the screening test begins, using either the Ashworth or Modified Ashworth Scale. Muscles with the greatest amount of spasticity should be tested, usually evaluated are resistance to hip abduction hip flexion, knee flexion and extension, and ankle dorsiflexion. An average score for the lower extremities should be calculated. The upper extremities may also be assessed but not included in the average score. There is not always a reduction in upper extremity spasticity during the test, but there may be an effect once the patient receives ITB Therapy with an implanted pump.
To perform the screening test, a bolus dose of 50 mcg of Baclofen injection is administered by lumbar puncture or an external intrathecal catheter.
After the drug bolus is administered, the examiner should assess spasticity on a regular, scheduled basis over an 8-hour period. The goal of the assessment is to quantify change in spasticity over time. In many centers, the physical therapist assesses the patient after the first hour and then at two - hours intervals. At each visit during the screening test, the physical therapist should use the Ashworth Scale calculate an average score for the lower extremities.
During the first 2 to 6 hours following the lumbar puncture, the patient should lie flat to minimize nausea, vomiting, and spinal headache. After that initial period, patients should be encouraged to get up to experience the effect of reduced spasticity on their movements or for caregivers to transfer and position the patient. The patient should be carefully monitored to prevent falls. It is important for the patient and the rehabilitation team to remember that the peck effects of the bolus test dose may be more intense that the actual ongoing effects of the actual pump.
Patients who respond to the bolus are candidates for ITB Therapy. At most centers, a positive response is a least at 1 point reduction in the average Ashworth score for the lower extremities, for one or two observations during the screening test.
Patients who do not respond to the first bolus dose can be re- tested over the next 2 days with bolus doses of 75 mcg and 100 mcg, if needed, administered 24 hours apart. Those who respond may then be scheduled for surgery to implant the pump.
Some patients become hypotonic during a screening test, which may be very disturbing to them. Reassure patients that the results of the screening test will be different from can be carefully titrated to meet their individual needs. An analogy some therapists have found useful is that the screening test is like a light switch that is either "on" or "off" The screening test determines whether spasticity can be "turned off" with intrathecal administration of Baclofen injection. In contrast, ITB Therapy with the SynchroMed pump is like a light on a dimmer switch. The drug can be titrated so that the patients have an optimal balance between symptom reduction and functional use of spasticity.
Suggestions for After Implant Rehabilitation Immediate post - op care
Most physicians believe that the patient should lie flat for two three days after implant to reduce nausea, vomiting, spinal headaches, injury to the surgical site and to promote handling. Hot packs should not be used around the pump implant site. After the initial period of bed rest, centers use an abdominal binder to minimize effusions and to protect the incisions.
Patient safety is a key consideration in the first week after implant. Caregivers may need training in body mechanics because the patient's body may be very different to lift, especially if the patient was very stiff prior to implant. Physical therapists should caution patients that their movement patterns will be different. They may need to learn new strategies for transferring and moving. It may be several weeks or months before the patient completely accommodates to the reduction of spasticity. The patient should avoid excessive trunk movement (bending twisting, overhead reaching, excessive trunk flexion beyond 45°) the first 4 week after implant to avoid catheter dislodgment. The amount of PT and OT involvement should be based on the patient's tolerance.
Aggressive therapy should not begin until incisions are well healed usually one month after implant.
The patient's seating system, equipment, assistive devices, orthoses and shoes should be evaluated to determine whether they continue to meet the patient's needs. The patient may need more support due to initial weakness and changes in movement patterns. Devices may fit differently after spasticity after spasticity is reduced, so the possibility of skin breakdown must also be considered sitting tolerance may increase on ITB Therapy, so seating systems need tom be examined to ensure skin integrity is maintained, even with prolonged periods of sitting.
For patients whose ITB Therapy goal is improved ease of care and / or comfort, additional therapy is not usually indicated. For patients with goals of improved function, therapy is an important adjunct to ITB therapy. Intensive physical therapy (3-5 times per week) usually begins about a months after implant, on either an inpatient or an outpatient basis, depending on goals and resources. The waiting period before intensive therapy allows incisions to heal as well as time for the therapy dose to be titrated to a level that significantly reduces spasticity. It is not uncommon to frequently titrate the dose the first few weeks and months, until the precise result is achieved enabling the patient to make optimal gains in rehabilitation.
Regardless of whether the patient has undergone therapy before implant, the patient should be evaluated as a new patient. With reduced spasticity, the patient may be able to make significant advances that were previously possible. When appropriate the therapist should work with caregivers to implement a home program to augment the facility - based program.
During this intensive period, therapeutic exercise to strengthen weakened muscle groups and to stretch shortened muscles is important. Motor learning is important in making functional gains. New patterns of movement need to replace patterns of inefficient movement. Rapid or forceful trunk rotation is not appropriate due to the risk of dislodging the catheter. Modalities, such as ultrasound, heat, or electrical stimulation, may be used, but not directly over or around the pump site.
Seating evaluations for optimal positioning are important. A patient with spastic hamstring muscle may have been positioned in hyper - knee flexion before pump implant. With less spasticity, this position is no longer necessary, but the patient may need significant encouragement to change sitting posture. Existing splints and orthoses may need modifications to allow patients to achieve more ideal function and position. All adaptive equipment should be evaluated as the patient progresses and modified as necessary.
In the first few months after implant, the patient's dose will most likely require several adjustments. The rehabilitation team can provide valuable information to the physician regarding the dose adjustments that might benefit the patient. If spasticity is interfering with function, the dose may need to be increased. Some patients benefit from an increase in medication during the day to allow some spasticity for sitting and transfers. Other patients need a complex dosing pattern depending on fluctuations in tone throughout the day. Dosing schedules are individually set to benefit the patient depending on activities and needs. Each time, the dose is adjusted, the patient needs to accommodate to the change. Rehabilitation is an ongoing process, and some patients do not make functional gain until several months after implant. Reassure patients that strengthening and motor learning takes time.
After rehabilitation goals are met, intervention often shifts to a home program or community - based recreational activities, such as swimming, cycling or wheelchair basketball. The point of transition depends on progress towards goals, resources and needs of patient and family.
Some facilities routinely schedule a comprehensive interdisciplinary follow-up evaluation of the patient after implant. This follow - up visit may be scheduled as early as six weeks after implant. For patients who have goals of improved function, the evaluation may be more effective at six months to one year after implant. At that time, therapists formally re- evaluate the patients with the outcome measures performed at baseline. Seating devices, assistive devices, and orthoses should be re- evaluated to determine effectiveness with appropriate recommendations for modifications or new equipment.
Considerations regarding ITB therapy
The rehabilitation team should be aware of the following considerations in the management of patients after ITB Therapy: Lie flat for 2 to 3 days after pump implant to minimize nausea, vomiting, and spinal headache.
During the 2 to 4 weeks after surgery, avoid excessive trunk movement (bending, twisting, overhead reaching, excessive trunk flexion (beyond 45) to avoid catheter dislodgment.
Avoid heat - producing modalities (hot packs, diathermy and ultrasound) in the immediate area of the pump.
Advise the patient and caregivers of changes in body perceptions and the need to alter strategies for transfers and other activities. Also alert them to weakness in the trunk and lower extremities.
Recognize the symptoms of Baclofen overdose:
Drowsiness, lightheadedness, dizziness, somnolence, respiratory depression, seizures muscle weakness typically progressing upward from the lower extremities, and loss of consciousness progressing to coma. Contact the patient's doctor immediately. Dose adjustment is an ongoing process, with more frequent adjustments required in the first few months after implant to reduce spasticity and spasms without adverse side effects. Therapists should communicate frequently with the physician about dose titration.
- Patients need to adjust to new sensations with every change in their prescription.
- Patients should be weaned from their oral medication gradually by their physician, as abrupt withdrawal can cause severe hallucinations and seizure activity.
- Goals should be agreed upon by the patient, family and health care team prior to pump implant. Goals should be reassessed on a regular basis.
Thorough assessment is important in understanding and documenting therapy progress. Demonstrated progress toward stated goals is important not only to patients but also to third- party payers.