Neurological Symptoms

Published on 09/04/2015 by admin

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Last modified 09/04/2015

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27 Neurological Symptoms

The purpose of this chapter is to address symptoms etiologies that are an abnormality or dysfunction of the nervous system, and are not covered elsewhere in the book.

Neurological symptoms present particular difficulties for those working in pediatric palliative medicine. The evidence base for most symptom interventions derives largely from work done in adults. Historically, adult palliative medicine has largely addressed the needs of patients with cancer, while it is in the large group of children with non-cancer conditions that neurological symptoms occur most commonly.1 Typically, they are neurodegenerative conditions in which deterioration to death occurs over years or decades, and are characterized by severe neurological symptoms that may be difficult to treat.

The management of neurological symptoms in childhood is complicated both by the inherent intractability of many, and by the lack of a robust evidence base to support effective management. Nevertheless, the broad principles of good palliative care can and should be applied.

General Principles

The most important preparations for providing palliative care to children who may experience neurological symptoms are anticipation, education, and discussion. Informing the child, family, and caretakers about the potential symptoms at an appropriate time can help to reduce anxiety, stress, and unwanted admissions. Ensuring that families have strategies for managing symptoms in a way acceptable to them, even if it is only having the telephone number of someone who can help, will help meet the aims of palliative care. Many families report that honesty and unlimited support are critical elements of the palliative care process. Palliative care approaches should be multidimensional, in the best interest of the child, and rational.

Multidimensional

In considering the impact of neurological symptoms, professionals need to consider not only their physical effects, but also their influence on psychosocial, emotional, and spiritual issues. In focusing on reducing the frequency of seizures, for example, professionals should not lose sight of the need to allow a child to engage meaningfully with his or her family. This can lead to the involvement of a potentially large and extended team with varying but, at times, over-lapping roles (Box 27-1).

BOX 27-1 The Interdisciplinary Team

Rational

In establishing that a given intervention is in the child’s best interest, it is clearly necessary to be aware of the existing evidence. In an age where evidence-based medicine is a professional requirement,2 it is important that practice is not just based on anecdotes and experience, but also is justified with research. Critical appraisal and clinical reasoning must underpin practice. Systematic reviews or meta-analyses, where they exist, are authoritative sources of such evidence. Individual carefully designed double-blind trials are also powerful evidence. Anecdote and case history, however, are not indicators of effectiveness. They are important signposts to studies that should take place, but should not result in an uncritical change of practice by themselves.

The literature pertaining to non-pharmacological approaches to the management of neurological symptoms is particularly sparse. A rational and logical approach does not, however, mean that practice should be limited only to that rather narrow range of therapeutic options that have been subjected to study in children. It is often necessary to extrapolate from evidence in the adult specialty, or from related disciplines such as acute pain management. Sometimes, professionals working in pediatric palliative care need to be therapeutically creative, using a sound knowledge of pharmacology and therapeutics to develop an approach that, while it may not be fully supported by evidence, is nevertheless rational.

Complementary and alternative medicine (CAM) ap- proaches should be used in conjunction with conventional medicine to aim to provide better symptom control and meet the cultural, spiritual, and psychosocial needs of the child and family.3 Many neurological symptoms are exacerbated by depression, anxiety, and/or fatigue. There is evidence to suggest these are ameliorated by some CAM approaches, including massage,412 acupuncture,8,10,1316 and transcutaneous electrical stimulation (TENS)8,17 can offer some assistance with this. The effectiveness of TENS is unclear18,19 but it is well tolerated by most patients. Music therapy and hydrotherapy are naturally enjoyable interventions for children (Fig. 27-1).

Diazepam Short-term anxiety relief. Relief of muscle spasm. Treatment of status epilepticus Levomepromazine Antiemetic where cause is unclear, or where probably multifactorial. Secondary effects include sedation and analgesia Fentanyl Severe pain (synthetic opioid analgesic), particularly as rotation from morphine or if patch formulation desirable Hydromorphone Severe pain (opioid analgesic) especially if diamorphine unavailable and solubility is an issue Tizanidine Muscle spasm Baclofen Chronic severe spasticity of voluntary muscle Melatonin Sleep disturbance caused by disruption of circadian rhythm (not anxiolytic)

Seizures

Management of seizures outside the terminal phase is beyond the scope of this chapter. The palliative care professional should continue to liaise carefully with colleagues in neurology, even as death approaches. Potentially, this can achieve several important objectives:

Children with life-limiting conditions in ACT categories III and IV (Table 27-2), which are often chronic neurological conditions, are likely to have seizures that have been difficult to control for some time. The result is typically that, at the time it is clear a palliative phase has been entered, children are on a large number of different anticonvulsants.

The long-term management of seizures requires a neurologist to balance carefully immediate benefit with long-term side effects. In the palliative phase, such a balance may no longer be necessary. Discussion with neurology colleagues may allow:

Management of breakthrough seizures usually requires a parenteral approach. This presents a conflict with one of the aims of palliative care, which is to offer the family the choice of locations, typically home, hospital, or hospice, for death to occur. The intravenous and subcutaneous routes may not be appropriate, because they are not usually available except to professionals who may not be immediately on hand.

The solution to this is to use the buccal route. Small volumes of water soluble drugs such as midazolam and diamorphine can be administered between the cheek and the gum. They are absorbed rapidly through the oral mucosa, effectively providing an alternative parenteral route without needles. This is increasingly used for management of breakthrough seizures in neurology20 and is ideally suited to their management in the terminal phase.

The two mainstays of seizure management in the terminal stages are phenobarbital and midazolam. Both may be given as continuous subcutaneous infusion, though phenobarbital must be given separately from other medications. The decision as to which of these should be first-line use is largely up to the clinician; there is little evidence to suggest which is likely to be more effective, and it may depend on the individual circumstances and patient.

Phenobarbital is rarely used in seizure disorders because of the risk of adverse effect in long-term use. In the palliative phase, however, where these are unlikely to be a significant consideration, it has a number of potential advantages over many other anticonvulsants, though not all are proved. It is anxiolytic, rather than simply sedative,21 effective against cerebral irritation; is sedating it may have some activity against neuropathic pain.22 It can also be given orally or through a gastrostomy tube.

It does, however, also have some disadvantages:

It induces its own metabolism, so the dose may need to be kept under review; and its long half-life means it cannot easily be titrated against its effect, particularly if given orally.

Midazolam is a short-acting benzodiazepine. It is often used by neurologists for breakthrough seizures, but rarely for background control because of its short half-life. In the palliative phase, Midazolam is usually given by continuous subcutaneous infusion although there is no reason in principle why it should not also be given intravenously. It can be mixed with other medications in the same syringe driver, including diamorphine, morphine, levomepromazine, and other medications commonly used in the final days of life. It is easy to titrate against symptoms due to its short half-life; 23 powerfully anxiolytic, amnestic and sedating; and has a broad range of anticonvulsant activity. Midazolam is widely used in pediatric palliative care, so it has reasonable clinical experience and evidence base. Also, it is highly soluble so can be given by buccal route.

Midazolam’s disadvantages are that paradoxical agitation can occur in some children24 and its short half-life makes it inappropriate for background control of seizures except by parenteral infusion. The drug can cause confusion; and in cognitively aware children, loss of memory may be a disadvantage, particularly if it impairs family relationships.

The decision as to which is the better first-line approach will depend largely on individual circumstances. For a child who has otherwise no need for parenteral access, phenobarbital given orally may be preferable. For a child needing benzodiazepines for other reasons, midazolam may be the logical choice. For many children, adequate control of seizures in the terminal phase will in practice require both drugs to be given parenterally as the swallowing reflex becomes lost.

Breakthrough seizures

Before embarking on management of breakthrough seizures, it is important to discuss with the child’s family what their expectations are. Most families have lived with a child with complex seizure disorder for many years and will be able to fully engage in a discussion about what can and cannot be achieved in the way of control in the final days and weeks of life.

It is important to acknowledge that seizures are more unpleasant and frightening for those observing them than they are for the child who experiences them. If seizures do not appear to distress the child, then vigorous attempts to abolish them may result in replacing acceptable seizures with unacceptable adverse effects. For families used to a child who has many seizures a day, reducing them to only one or two seizures a day may be an acceptable outcome.

It is also important to acknowledge that complete control of seizures may simply not be possible. If complete absence of seizures can only be achieved by means of anesthesia and ventilation, from which there is no realistic prospect of the child’s recovering, it is a price too high for the child to pay. This needs to be explored with the family at the time management of terminal seizures is initiated.

It is usual for children with complex seizure disorders to have a detailed seizure protocol that has been agreed between neurologist and family. It is important that the palliative care pediatrician be aware of this protocol, and that he or she work carefully with the neurology team and the family themselves before suggesting any modification. This protocol should be accessible to all those involved with the child and identify what is normal for that child, when a seizure has become prolonged and requires medication, and at what stage and to what level further help should be sought if seizure activity continues.

One common medication used for treatment of breakthrough seizures, when indicated, is diazepam, which may be given by the rectal route. The metabolites of diazepam are active and long-lasting, but this is rarely a problem in children. Children prefer to avoid the rectal route where possible, as it is uncomfortable and undignified. Nevertheless, it is certainly preferred to a needle by most and may be the most accessible in the midst of a seizure. The rectal route is contraindicated in neutropenia or marked thrombocytopenia.