3. Indications for ITB

Baclofen pump implantation is indicated if patients have:


Patients with profound pain are preferred to have morphine pumps rather than baclofen.

#### 4. Screening test before implantation

All candidates for intrathecal baclofen (ITB) therapy were planned to perform screening trials before pumps implanted. The patient receives 25 μg of baclofen through lumbar puncture. The resulting hypotonia is measured using the Modified Ashworth score. Pulse rate, blood pressure, respiratory rate and any adverse effects (including seizures) should be recognized. A test is successful if the Ashworth score is reduced by at least two points from 4 to 8 h following administration. If this reduction is not achieved, a bolus dose is given the next day, with an increment of 25 μg up to a maximum bolus of 75 μg. The drug amount that reached a satisfactory test result is also used to guide us to give the initial dose after pump implantation. If the response obtained with 25 μg for 24 h or more, then the initial dose of the implanted pump will be 25 μg/day; if the duration of relaxation were less than 24 h, the initial dose of the implanted pump would be 50 μg/day.

### 5. Operation of pump implantation

Changes in pressure or temperature have influence on the flow rate, especially in hot countries. A baclofen overdose reported in some cases during summer time in several hot countries.

These are now widely used nowadays. These pumps have a drug reservoir from which they automatically dispense a programmed amount of medication through a catheter. These pumps have a small, on-board battery and integrated microelectronic circuits to control the drug

In this chapter we will discuss the rationale for the use of this mode of treatment in spasticity.

1. Sever spasticity grade 3 and above (equal or more than 12 months duration). This spasticity significantly interfere with voluntary movement, causing difficulty in maintaining range of motion or position. It even affects safety, contributing to pain or skin breakdown

2. Spasticity refractory to oral medications (baclofen) or having unacceptable side effects.

Patients with profound pain are preferred to have morphine pumps rather than baclofen.

All candidates for intrathecal baclofen (ITB) therapy were planned to perform screening trials before pumps implanted. The patient receives 25 μg of baclofen through lumbar puncture. The resulting hypotonia is measured using the Modified Ashworth score. Pulse rate, blood pressure, respiratory rate and any adverse effects (including seizures) should be recognized. A test is successful if the Ashworth score is reduced by at least two points from 4 to 8 h following administration. If this reduction is not achieved, a bolus dose is given the next day, with an increment of 25 μg up to a maximum bolus of 75 μg. The drug amount that reached a satisfactory test result is also used to guide us to give the initial dose after pump implantation. If the response obtained with 25 μg for 24 h or more, then the initial dose of the implanted pump will be 25 μg/day; if the duration of relaxation were less than 24 h, the initial dose of the

2.5. Variable-rate pumps

116 Cerebral Palsy - Clinical and Therapeutic Aspects

3. Indications for ITB

4. No hypersensitivity to baclofen.

Baclofen pump implantation is indicated if patients have:

5. No medical comorbidity to surgical intervention.

4. Screening test before implantation

implanted pump would be 50 μg/day.

and making personal care difficult for you or your caregiver.

3. Positive response to ITB at test dose 100 μg with no response to placebo.

delivery.

The pump is inserted under the covering of the abdominal muscles, while the patient is under a general anesthetic. A small catheter is then inserted through a Touhy needle into the thecal sac. When spinal fluid appeared, a spinal catheter threaded upward to a site depends on the distribution of the patient's spasticity (i.e., to the T10-11 spinal segment level for patients with spastic paraplegia and the C7-T4 spinal segment level for those with spastic quadriparesis. The catheter is then tunneled under the skin to the abdomen and is connected to the pump. The incision is closed with suture material or surgical staples. The procedure usually lasts 1–2 h.

#### 6. Dosing of intrathecal baclofen

After implantation, we will fill the pump with baclofen, the pump is then programmed with certain external programmer, for example, N-vision. In all the cases, we prefer to use the "simple continuous infusion". ITB doses are titrated over the next few months. Initially, the infusion often begins at 25–50 μg/day and the dose is titrated gradually by 10–20%, a week incensement until the patient's spasticity significantly reduced. The dose then adjusted with less frequent periods on an outpatient basis. In most of the patients, the satisfactory dose is usually achieved within 2 months.

Refills are generally done every 3–9 months, a refill kit is provided with a sterile needle and syringe. The filling is done in the outpatient just by passing the needle to the pump through the skin of the abdomen. Pumps hold 20 or 40 ml and will signal with a beeping noise if the amount gets below 2 ml. The devices also sound alarms if there is a malfunction, or if the battery runs low (generally between 3 and 7 years of use). When the battery runs low, the implant will be replaced under local anesthesia.

#### 7. Prognosis

We conducted a study of 55 patients with spasticity, who had baclofen pump implantation in Neuroscience Hospital, Baghdad, from October 2011 to December 2016 [2]. The spasticity decreased, significantly in the lower extremities and remained so during the 2.9 years of infusion. In 55 patients (41 patients with a spinal cause of spasticity and 14 patients with spasticity caused by cerebral palsy), the results were remarkable.

Comparing our data with other international studies (Table 2) [3–10], the 2.9 years follow-up quite objectively concluded the efficiency of use of the pump to treat spasticity.

Many review papers were published to assess the efficiency of the baclofen pump. Butler and Campbell [11] in 2000 reviewed 12 published studies on ITB. They concluded that spasticity improved and that limb functions probably improved with ITB.


The most frequent complication was catheter malfunction (e.g., disconnection of the catheter tip from the pump, drug leakage from the catheter and migration of the catheter outside the thecal sac).

Baclofen Pump Implantation for Cerebral Palsy http://dx.doi.org/10.5772/intechopen.79619 119

Sudden cessation of ITB infusion can occur when the pump running empty; programming error; incorrect baclofen concentration; a problem with the catheter system and a problem with the battery. Some of these problems will activate the alarm. It is followed within a few hours by symptoms of generalized pruritus, increased spasticity and agitation. The symptoms may range in severity from mild to severe [15, 16]. The Classic symptoms of baclofen withdrawal are a sudden increase or return of your spasticity or tone, profuse sweating and itching without an associated rash. Fever, tachycardia, tachypnea, hypotension or hypertension or even confusion. Severe withdrawal symptoms include hallucinations or delirium, seizures, rhabdomyolysis, organ failure and even death. We noticed some patients might not recognize the mild withdrawal symptoms; consequently, the interruption in therapy may not detect. Severe withdrawal symptoms are severe complications and must manage urgently. Moderate withdrawal symptoms are managed by high doses of oral baclofen (e.g., 10–20 mg every 4 h), intravenous benzodiazepines (diazepam, 2–5 mg every 6 h) or bolus baclofen injections can be given too [17]. Despite the complications reported in many papers, almost 90% of patients with baclofen pump implantation at the end of the battery life prefer to have a new pump

This is far less common than withdrawal. The overdose could be a human error in dosing, programming or filling the pump; system malfunction or unsafe combination of intrathecal and oral medications. Most of the time, mild overdose symptoms can be easily managed by turning the pump rate of infusion down. The mild symptoms are characterized with low muscle tone, low attention, lightheadedness and sleepiness. Moderate symptoms are bradycardia, respiratory depression and difficulty awakening. When sever symptoms developed the hypotonia spreads to the trunk, arms, face and neck. Stupor, coma, seizures, severely slowed breathing that needs mechanical ventilation and eventually death. Some papers recommend an intravenous injection of 1–2 mg of physostigmine to treat overdoses, but their therapeutic effects are minimal and brief [21, 22]. Severe overdoses may necessitate assisted ventilation. CSF aspiration may also help with severe overdoses: 20 ml of CSF is withdrawn and replaced

with 20 ml of a 5% dextrose to 0.25% normal saline solution 2 or 3 times [22].

Infection occurs in 5–10% of patients mostly caused by Staphylococcus aureus [19].

Most infections that start in the first 3 weeks after surgery are due to bacterial contamination at the time of pump insertion. Those related to future pump refills are extremely rare. Infections can occur either at the site of pump implantation, that is, anterior abdominal wall. This will result in erythema, swelling, tenderness and fever. It is treated with intravenous antibiotics and surgical cleaning of the pump wound. In severe cases, the infection may affect the whole

8.1. Baclofen withdrawal

exchanged and to continue ITB therapy [18].

8.2. Baclofen overdose

8.3. Infections

Table 2. Comparison of the outcomes from international data.

In our study, we concluded that spasticity decreased significantly in the lower limbs and to a lesser extent in the upper extremities. The Ashwarth scale remains low during the years of infusion. Westbom et al. in 2003 reported in a multicenter study a sustained decline in the Ashworth scores in both lower and upper extremities during a 6-year follow-up [12].

The reduction of upper limbs spasticity is usually less than that noticed in the lower extremities; if the catheter tip was at the mid-thoracic level or lower. Motta et al. [13] evaluated ITB's effect on the upper extremities of 20 patients with quadriplegic cerebral palsy with a mean age of 11.4 years. The spasticity of the upper extremity decreased (P b 0.05), and the range of movement improved remarkably.

The range of motion in the lower limbs increased following ITB therapy due to the reduction of spasticity. Further, this accompanied by an improvement in the gait. In our study, improvement in gait noticed in 10 patients (4 with multiple sclerosis, 3 with cerebral palsy and 3 with partial spinal cord injury). Gerstzen et al. [14] studied the effect of ITB on gait. They classified gait functionality into four types (community, household, non-functional and nonambulatory). In their study, 24 patients had some ambulation before ITB therapy. The level of ambulation was improved by one level in nine patients, worsened in three and unchanged for the remaining patients.

#### 8. Complications


The most frequent complication was catheter malfunction (e.g., disconnection of the catheter tip from the pump, drug leakage from the catheter and migration of the catheter outside the thecal sac).

#### 8.1. Baclofen withdrawal

Sudden cessation of ITB infusion can occur when the pump running empty; programming error; incorrect baclofen concentration; a problem with the catheter system and a problem with the battery. Some of these problems will activate the alarm. It is followed within a few hours by symptoms of generalized pruritus, increased spasticity and agitation. The symptoms may range in severity from mild to severe [15, 16]. The Classic symptoms of baclofen withdrawal are a sudden increase or return of your spasticity or tone, profuse sweating and itching without an associated rash. Fever, tachycardia, tachypnea, hypotension or hypertension or even confusion. Severe withdrawal symptoms include hallucinations or delirium, seizures, rhabdomyolysis, organ failure and even death. We noticed some patients might not recognize the mild withdrawal symptoms; consequently, the interruption in therapy may not detect. Severe withdrawal symptoms are severe complications and must manage urgently. Moderate withdrawal symptoms are managed by high doses of oral baclofen (e.g., 10–20 mg every 4 h), intravenous benzodiazepines (diazepam, 2–5 mg every 6 h) or bolus baclofen injections can be given too [17]. Despite the complications reported in many papers, almost 90% of patients with baclofen pump implantation at the end of the battery life prefer to have a new pump exchanged and to continue ITB therapy [18].

#### 8.2. Baclofen overdose

In our study, we concluded that spasticity decreased significantly in the lower limbs and to a lesser extent in the upper extremities. The Ashwarth scale remains low during the years of infusion. Westbom et al. in 2003 reported in a multicenter study a sustained decline in the

Reference Country Patient no. Type of study Result Kvascevicius et al. [5] Lithuania 5 Prospective Very good Baker et al. [6] United States 117 Prospective Excellent Penn [7] United States 18 Double blind Excellent Coffey et al. [8] United States 75 Double blind Excellent Muller [9] Germany 211 Prospective, multicenter Excellent Lazorthes et al. [10] Belgium/Holland 18 Prospective Excellent Jierski et al. [11] Germany/Sweden 28 Prospective, multicenter Excellent Penn et al. [12] United States 62 Prospective Excellent

The reduction of upper limbs spasticity is usually less than that noticed in the lower extremities; if the catheter tip was at the mid-thoracic level or lower. Motta et al. [13] evaluated ITB's effect on the upper extremities of 20 patients with quadriplegic cerebral palsy with a mean age of 11.4 years. The spasticity of the upper extremity decreased (P b 0.05), and the range of

The range of motion in the lower limbs increased following ITB therapy due to the reduction of spasticity. Further, this accompanied by an improvement in the gait. In our study, improvement in gait noticed in 10 patients (4 with multiple sclerosis, 3 with cerebral palsy and 3 with partial spinal cord injury). Gerstzen et al. [14] studied the effect of ITB on gait. They classified gait functionality into four types (community, household, non-functional and nonambulatory). In their study, 24 patients had some ambulation before ITB therapy. The level of ambulation was improved by one level in nine patients, worsened in three and unchanged for

6. Hardware-related complications during surgery are rare, but can include catheter migration. After surgery though, the potential hardware complications include catheter fracture

Ashworth scores in both lower and upper extremities during a 6-year follow-up [12].

1. Pain, numbness, weakness or paralysis due to nerve damage (rare)

movement improved remarkably.

118 Cerebral Palsy - Clinical and Therapeutic Aspects

Table 2. Comparison of the outcomes from international data.

the remaining patients.

8. Complications

4. Infections

2. Cerebrospinal fluid leak

3. Bleeding/injury to blood vessels

5. General anesthetic complications

or migration and infection or pump malfunction.

This is far less common than withdrawal. The overdose could be a human error in dosing, programming or filling the pump; system malfunction or unsafe combination of intrathecal and oral medications. Most of the time, mild overdose symptoms can be easily managed by turning the pump rate of infusion down. The mild symptoms are characterized with low muscle tone, low attention, lightheadedness and sleepiness. Moderate symptoms are bradycardia, respiratory depression and difficulty awakening. When sever symptoms developed the hypotonia spreads to the trunk, arms, face and neck. Stupor, coma, seizures, severely slowed breathing that needs mechanical ventilation and eventually death. Some papers recommend an intravenous injection of 1–2 mg of physostigmine to treat overdoses, but their therapeutic effects are minimal and brief [21, 22]. Severe overdoses may necessitate assisted ventilation. CSF aspiration may also help with severe overdoses: 20 ml of CSF is withdrawn and replaced with 20 ml of a 5% dextrose to 0.25% normal saline solution 2 or 3 times [22].

#### 8.3. Infections

Infection occurs in 5–10% of patients mostly caused by Staphylococcus aureus [19].

Most infections that start in the first 3 weeks after surgery are due to bacterial contamination at the time of pump insertion. Those related to future pump refills are extremely rare. Infections can occur either at the site of pump implantation, that is, anterior abdominal wall. This will result in erythema, swelling, tenderness and fever. It is treated with intravenous antibiotics and surgical cleaning of the pump wound. In severe cases, the infection may affect the whole system, including the catheter and cerebrospinal fluid (CSF). It requires removal of the entire pump with postoperative parenteral antibiotics for 3 weeks [19].

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#### 8.4. CSF leaks

Leak may appear due to insertion of Tuohy needle with a catheter. The incidence is from 5 to 15% in patients with CP (most of whom are children), in contrast to the 3% leak rate reported in adults. The difference explained by malnutrition of chronically disabled children, thinner tissue masses, the smaller body size and the presence of higher CSF pressures associated with occult hydrocephalus [20].
