Typical Teenager...
Answer B
This girl suffers from severe spasticity due to her cerebral palsy. Cerebral palsy (CP) is associated with an array of potential insults in the fetal and neonatal period, such as severe prematurity (typically very low birth weight), intrauterine growth retardation, neonatal asphyxia or hypoxia, stroke, or other genetic conditions. Infants may be diagnosed over a period of months, as subtle neurologic findings accumulate (motor delay, persistence of primitive reflexes, abnormal postural reactions to stimuli) and elucidate the underlying disorder. Over 50% of children with CP have intellectual delay, but many are high-functioning.
Broadly speaking, CP can be categorized into three main syndromes, defined by dominant symptoms: spastic, dyskinetic, and ataxic. Symptoms and signs may be asymmetric (both across the midline or upper extremity versus lower extremity) or variable in severity depending on the context. Spasticity can be especially disabling and limiting if severe. The typical approach is to start with conservative therapy, such as oral medications (e.g. baclofen, diazepam, clonidine); invasive treatment includes chemical neurolysis (with injection of phenol into nerve root) and dorsal rhizotomy (electromyography guides the neurosurgeon to identify and ablate the spasticity-causing nerve fibers). If this fails, an intrathecal baclofen pump may be considered. A silastic catheter is inserted into the intrathecal space, tunneled to a pump and reservoir which is typically implanted in the subcutaneous abdomen. The pump can be refilled every few months percutaneously, and programmed at any time via a wireless unit; the battery life is typically 5-7 years. Vender et al (2006) found a significantly higher complication rate of these pumps in children compared to adults.
The pump may present various acute and delayed complications. The simplified ED approach can focus on three factors: the catheter (tear, kink, migration), the pump (malfunction, infection), and the patient (Twiddler’s syndrome – analogous to cardiac pacemaker patients).
Microleak syndrome should be considered when the patient experiences posture-related changes in the amount of baclofen administered. When supine, the pump directs medicine against a low CSF pressure, e.g. 10 cmH20. When upright, CSF pressures (especially with spasticity) may reach as high as 50-70 cmH20; this high CSF pressure can create backflow into the catheter and pump, causing less medication to be administered, or causing leaking of the medication through a microscopic rent in the catheter system. The result is good spastic control when supine, but less medication given when upright. Since this microtear may not show up on any dye study, the first screening test is to elicit (by history or demonstration) postural changes in baclofen administration, which can easily be shown bedside in the ED (B).
Admitting the patient for observation may be the final disposition, but at this point, the indication would be unclear in a currently asymptomatic patient without a presumptive diagnosis (A); further, there is no overt evidence of caregiver burnout at this time (but always important to assess).
Some patients may have supplemental PO baclofen, but the change in pump-administered dose during the day should alert the provider to a problem with the unit; simply supplementing without further investigation or interrogation of the unit is premature (C).
Although chronic disease puts this child at a higher risk of mental health challenges, there is no evidence for this at this time (D). Organic causes of her somnolence and loss of daily functioning should be sought before her symptoms are ascribed to a psychiatric cause.
Modalities for further investigation include plain radiographs (kinking, dislodgement, migration) and CT with contrast (finer detail, seroma, abscess, flipped pump). MRI may be used, but a careful specific protocol is needed (and the magnet will turn off the pump). Early consultation with Neurosurgery and/or Physical Medicine and Rehabilitation (PMR) is advised (PMR may interrogate and adjust pump if needed).
References
Vender JR, Hester S, Waller JL, Rekito A, Lee MR. Identification and management of intrathecal baclofen pump complications: a comparison of pediatric and adult patients. J Neurosurg. 2006 Jan;104(1 Suppl):9-15.
Gooch et al. Complications of intrathecal baclofen pumps in children. Pediatr Neurosurg. 2003; 39:1-6
This girl suffers from severe spasticity due to her cerebral palsy. Cerebral palsy (CP) is associated with an array of potential insults in the fetal and neonatal period, such as severe prematurity (typically very low birth weight), intrauterine growth retardation, neonatal asphyxia or hypoxia, stroke, or other genetic conditions. Infants may be diagnosed over a period of months, as subtle neurologic findings accumulate (motor delay, persistence of primitive reflexes, abnormal postural reactions to stimuli) and elucidate the underlying disorder. Over 50% of children with CP have intellectual delay, but many are high-functioning.
Broadly speaking, CP can be categorized into three main syndromes, defined by dominant symptoms: spastic, dyskinetic, and ataxic. Symptoms and signs may be asymmetric (both across the midline or upper extremity versus lower extremity) or variable in severity depending on the context. Spasticity can be especially disabling and limiting if severe. The typical approach is to start with conservative therapy, such as oral medications (e.g. baclofen, diazepam, clonidine); invasive treatment includes chemical neurolysis (with injection of phenol into nerve root) and dorsal rhizotomy (electromyography guides the neurosurgeon to identify and ablate the spasticity-causing nerve fibers). If this fails, an intrathecal baclofen pump may be considered. A silastic catheter is inserted into the intrathecal space, tunneled to a pump and reservoir which is typically implanted in the subcutaneous abdomen. The pump can be refilled every few months percutaneously, and programmed at any time via a wireless unit; the battery life is typically 5-7 years. Vender et al (2006) found a significantly higher complication rate of these pumps in children compared to adults.
The pump may present various acute and delayed complications. The simplified ED approach can focus on three factors: the catheter (tear, kink, migration), the pump (malfunction, infection), and the patient (Twiddler’s syndrome – analogous to cardiac pacemaker patients).
Microleak syndrome should be considered when the patient experiences posture-related changes in the amount of baclofen administered. When supine, the pump directs medicine against a low CSF pressure, e.g. 10 cmH20. When upright, CSF pressures (especially with spasticity) may reach as high as 50-70 cmH20; this high CSF pressure can create backflow into the catheter and pump, causing less medication to be administered, or causing leaking of the medication through a microscopic rent in the catheter system. The result is good spastic control when supine, but less medication given when upright. Since this microtear may not show up on any dye study, the first screening test is to elicit (by history or demonstration) postural changes in baclofen administration, which can easily be shown bedside in the ED (B).
Admitting the patient for observation may be the final disposition, but at this point, the indication would be unclear in a currently asymptomatic patient without a presumptive diagnosis (A); further, there is no overt evidence of caregiver burnout at this time (but always important to assess).
Some patients may have supplemental PO baclofen, but the change in pump-administered dose during the day should alert the provider to a problem with the unit; simply supplementing without further investigation or interrogation of the unit is premature (C).
Although chronic disease puts this child at a higher risk of mental health challenges, there is no evidence for this at this time (D). Organic causes of her somnolence and loss of daily functioning should be sought before her symptoms are ascribed to a psychiatric cause.
Modalities for further investigation include plain radiographs (kinking, dislodgement, migration) and CT with contrast (finer detail, seroma, abscess, flipped pump). MRI may be used, but a careful specific protocol is needed (and the magnet will turn off the pump). Early consultation with Neurosurgery and/or Physical Medicine and Rehabilitation (PMR) is advised (PMR may interrogate and adjust pump if needed).
References
Vender JR, Hester S, Waller JL, Rekito A, Lee MR. Identification and management of intrathecal baclofen pump complications: a comparison of pediatric and adult patients. J Neurosurg. 2006 Jan;104(1 Suppl):9-15.
Gooch et al. Complications of intrathecal baclofen pumps in children. Pediatr Neurosurg. 2003; 39:1-6