Outpatient respiratory management of the child with severe neurological impairment
- 1Department of Paediatric Neurology, Addenbrookes Hospital, Cambridge, UK
- 2Paediatric Intensive Care Unit, University of Cambridge, Addenbrookes Hospital, Cambridge, UK
- 3Department of Paediatrics, Peterborough City Hospital, Peterborough, UK
- Correspondence to Dr Richard Brown, Department of Paediatrics, Peterborough City Hospital, Bretton Gate, Peterborough PE3 9GZ, UK;
- Received 7 November 2012
- Revised 26 February 2013
- Accepted 13 March 2013
- Published Online First 18 April 2013
Most paediatricians will have faced the challenge of managing respiratory problems in the child with severe neurological impairment. These children are under-represented in clinical trials, and data is therefore often extrapolated from other groups, for example children with cystic fibrosis. This means that robust evidence for respiratory management in children with severe neurological impairment is often lacking. Here we have attempted to piece together the existing evidence to provide a rational approach to the management of respiratory problems in children with severe neurological impairment. We also hope to highlight areas of uncertainty, in order to aid honest discussions with families. The respiratory management of the child with neuromuscular disease is beyond the scope of this article.
Children with severe neurological impairment (figure 1) are a small but important group of the paediatric population. Their numbers are difficult to quantify, but cerebral palsy with the severest form of motor impairment has a prevalence of 0.4 per 1000 live births.2 Respiratory illness is the most common reason for admission to hospital in children with neurodisability.3 Respiratory infection carries a higher morbidity and mortality,4 ,5 with respiratory illness being the most common cause of death in these children.6–8 There are specific factors which contribute to respiratory disease in affected children. These include reduced cough effectiveness, abnormalities of swallow and bulbar function, restrictive lung disease, gastro-oesophageal reflux, chronic colonisation with resistant bacteria, and the development of bronchiectasis. Other paediatric respiratory conditions such as asthma will also be represented in this population.9–11
Management of the respiratory health of children with severe neurological impairment provides challenges on many levels. Performing randomised controlled trials (RCTs) in this population is felt to be difficult, meaning a lack of quality evidence.10 However, RCTs in vulnerable groups can be ethical, and without good evidence for respiratory management, it seems unethical not to perform them.12 The lack of clear evidence means that risks and benefits of therapies can be difficult to assess. The aim of this piece is not to present a definitive evidence-based protocol, as there is insufficient data to support this. Instead, we set out the existing evidence and suggest a rational approach to management, leaving scope for individual clinician interpretation, and allowing informed discussion with the parents.
Nutrition and gastro-oesophageal reflux disease
Feeding problems occur in 30–40% of children with cerebral palsy and are associated with poor health status.13 This area was reviewed recently by Andrew et al.14 Malnutrition is associated with increased susceptibility to respiratory illness.9
The use of gastrostomy tube feeding has benefits in improving weight, decreasing feeding times, and improving the quality of life of carers.15–17 A potential for overnutrition and obesity can also exist which may also compromise respiratory function.18 ,19 Monitoring nutrition as part of an annual multidisciplinary review is valuable.
The potential for adverse effects from gastrostomy has also been raised and in particular there remains uncertainty about the interplay of gastrostomy tube feeding and gastro-oesophageal reflux disease (GORD). Cochrane reviews on gastrostomy versus oral feeding, and anti-GORD surgery versus medication in children with neurological impairment found no relevant RCTs.20 ,21 Gastrostomy tube placement in combination with anti-GORD surgery is often used on the reasoning that a gastrostomy tube might provoke difficult-to-treat reflux.22 However a number of studies indicate no increase in GORD after gastrostomy tube insertion in this population and that if GORD was provoked it could usually be controlled medically.23–25 Performing concomitant anti-GORD surgery appears to be associated with a higher rate of complications,26 not necessarily reduced by a laparoscopic approach which may be associated with an increased need for repeated surgery.27 A pragmatic approach would be to avoid concomitant anti-GORD surgery, instead performing this at a later stage in those children with proven GORD which has failed to respond to maximum medical therapy.22 ,27
At the heart of this debate is the unresolved question of whether GORD contributes to respiratory symptoms in children with severe neurological impairment. Conflicting studies show an increase, decrease or no change in the number of respiratory tract infections following anti-GORD surgery.27–29 The lack of a clear benefit may be partly because direct aspiration of food, fluid and saliva from the oropharynx is more important than reflux aspiration in causing respiratory infection.30 The presence of neurological impairment itself also appears to be associated with less improvement in respiratory symptoms, higher rates of repeated surgery and more frequent complications following anti-GORD surgery.31–35
With the lack of clear evidence, decisions about gastrostomy placement and the use of medical or surgical interventions for GORD will need to be tailored to the individual child and their circumstances. An honest discussion about the limitations of our knowledge with the child and those who speak for him or her is important.
Bulbar dysfunction, upper airways obstruction, swallowing and aspiration
Poiseuille's exponential relationship between flow and the radius of the airway, memorised by generations of medical students, is affected by airway tone, oral secretions and viral illness. For children with severe neurological impairment, bulbar dysfunction, GORD, kyphoscoliosis, posture, poor muscular tone and seizures may all independently (or together) cause significant upper airway problems.
During sleep, upper airways problems are more obvious. Obstructive sleep apnoea (OSA) is more common in children with severe neurological impairment. Clues to its presence include night-time fidgeting, snoring, coughing or apnoea, and daytime sleepiness.36 Overnight pulse oximetry can indicate whether significant desaturations are occurring, but formal polysomnography is required to differentiate central from obstructive causes of apnoea. Direct examination with fibre optic laryngoscopy is helpful in investigating obstructive apnoea, although a general anaesthetic is required. Formal polysomnography may negate the need for invasive laryngoscopy. Tonsillectomy, adenoidectomy and aryepiglottic surgery have all been proposed as a methods to treat OSA in children, including those with neurological impairment.37 ,38 Overnight continuous positive airway pressure (CPAP) can improve sleep quality, daytime alertness and quality of life in children with cerebral palsy.39 Topical steroid and non-sedating antihistamines are frequently considered for allergic rhinitis which may contribute to OSA, but a Cochrane review of therapies for sleep showed a lack of evidence for specific medical treatments.40
Direct aspiration of oral food and saliva is common, often silent, and an important factor in recurrent pneumonia.11 ,30 A speech and language review (including consideration of video fluoroscopy) should be arranged in those with difficulty feeding orally or recurrent chest infections.11 ,30 w1 In some where these assessments confirm direct aspiration of feeds, consideration should be given to stopping oral feeds. In making this decision, the risk of aspiration should be weighed against the benefits of pleasure from oral feeding.
Saliva handling can be significantly impaired which alone can cause choking and coughing which can be distressing and frightening for the child. Drooling may also occur, causing skin irritation and discomfort when clothing becomes wet. Again there is a lack of good quality evidence about drug therapy in the treatment of drooling of saliva.11 ,30 w2 Hyoscine patches that contain the antimuscarinic tropane alkaloid scopolamine are often considered. It is useful to titrate dose to the effect required and to consider the potential for central nervous system effects, an unpleasantly dry mouth and dental problems. Glycopyrrolate is a synthetic quaternary amine designed not to cross the blood brain barrier and is usually given orally. Often given as an alternative to hyoscine it can rarely be associated with urinary retention, confusion and problems of temperature control associated with impaired sweating; withdrawal of the treatment is associated with rebound phenomena. More recently botulinum toxin A treatment has emerged, and in more intractable situations surgery is used.w2 Botulinum toxin A therapy is an effective short term therapy but in a minority of cases is associated with worsening of dysphagia and pneumonia. Surgical treatments are usually reserved for a carefully selected minority in whom symptoms are most troublesome. There is evidence that surgical ligation of the salivary glands may reduce the incidence of pneumonia.w1 Laryngotracheal separation is a surgical procedure where the trachea is divided and the inferior portion bought out to the skin to form a stoma. This results in good control of aspiration, which may produce a reduction in the frequency of respiratory infections.w3 With treatments to reduce salivary quantity comes a risk of producing thickened secretions which may be harder to clear and exacerbate aspiration, mucous plugging and atelectasis.w1 w4 The management of drooling is summarised in table 1.
Approach to infections
The most common and severe infectious threats to children with severe neurological impairment are respiratory viruses. This was highlighted in the recent H1N1 influenza pandemic. For those with coexisting neurological disorders including cerebral palsy there was a higher hospitalisation rate and associated mortality.4 ,5 Children and their carers should be offered yearly influenza vaccination and be educated to the risks of viral infection.4 ,5 w7 Schools and institutions caring for these vulnerable children have a responsibility to reduce viral spread by promoting the use of hand washing and other infection control measures during the respiratory virus season.
Children may develop chronic lung disease secondary to recurrent aspiration, less effective airway clearance with coughing and the effects of kyphoscoliosis. In some, bronchiectasis may occur. Where antibiotic treatment is needed, understanding which organisms are more likely to be responsible is helpful in choosing antibiotics for acute infection, and when considering prophylaxis box 1. A few studies address this issue directly. In addition to respiratory viruses, community acquired bacteria (including anaerobes) and hospital acquired pathogens are common.w8 w9 Repeated treatment for infection and contact with other children in hospital who have received repeated antibiotic courses may lead to the colonisation of a child with severe neurological impairment with resistant organisms.w9 The incidence of colonisation with opportunistic pathogens such as Pseudomonas aeruginosa has not been reported, but is seen commonly in our personal practice and in children with a tracheostomy. P aeruginosa are ubiquitous bacteria, usually of low pathogenicity, which may colonise damaged tissue. It is difficult to treat with the recommended first-line antibiotic regimes for community acquired pneumonia. Eradication therapy is recommended after the first positive P aeruginosa culture in cystic fibrosis (CF) and non-CF bronchiectasis, and is effective in the short term.w10 w11 Specific data relating to children with severe neurological impairment is lacking. One limited series suggested a reduction in the incidence of pneumonia in three patients with severe cerebral palsy after 12 months of treatment with nebulised tobramycin.w12 Colistin is considerably less expensive than tobramycin at present, and they appear to be equally effective in CF.w13 Despite the lack of data on antipseudomonal therapy in children with severe neurological impairment, its use is often considered. A pragmatic approach would be to attempt P aeruginosa eradication after the first colonisation, and to consider a trial of nebulised colistin in children known to be colonised who have frequent hospital admissions with respiratory illness. In view of the lack of current evidence of this relatively expensive treatment, it is reasonable to plan to discontinue the nebulised antipseudomonal therapy after 1 year if there is no reduction in the number of hospital admissions.
Ensure sputum samples sent (with help of physiotherapy and suctioning);
Antibiotics to cover common community acquired organisms and anaerobes (if aspiration possible);
Consider covering resistant/opportunistic organisms if isolated in the past or not improving on first-line antibiotics.
All routine childhood vaccinations;
Seasonal influenza vaccine (carers too);
23-valent pneumococcal vaccine (after second birthday);
Consider prophylactic oral antibiotics if >3 episodes of pneumonia/year;
Be guided by respiratory microbiology results when choosing antibiotic;
Use for 12 months then reassess; be vigilant for resistant organisms.
Consider eradication therapy on first Pseudomonas aeruginosa isolate;
First line is 2 weeks oral ciprofloxacin; if fails then either:
2 weeks intravenous antipseudomonal antibiotics or
further 4 weeks oral ciprofloxacin plus 3 months nebulised colistin or
3 months nebulised colistin alone.
Nebulised antipseudomonal therapy
Consider prophylactic nebulised colistin if frequent hospital admissions with pneumonia, in the presence of serial pseudomonas isolation;
Use for 12 months then reassess.
Antibiotics are often prescribed prophylactically in children with severe neurological impairment and frequent respiratory illness.9 At present, there is no evidence that prophylactic antibiotics reduce the frequency or severity of chest infections in children with severe neurological impairment. Any support for the use of such antibiotics is derived from studies of children with CF in whom long term macrolides appear to be safe and effective.w14 There is a risk of colonisation of the respiratory tract with antibiotic-resistant organisms Macrolides have a number of actions: they directly kill common respiratory bacteria, inhibit the virulence of P aeruginosa and have anti-inflammatory properties.w14 Azithromycin has a long half-life and can be given three times a week, reducing the burden of medication on the family. Other antibiotics may also be used as prophylaxis, including co-amoxiclav and co-trimoxazole. However, if prophylaxis is used, it should be reviewed on an annual basis. Consider switching antibiotics if resistance develops (as guided by sputum cultures), or stopping them if no clinical gain has been seen.
Vascular access can become problematic in those children who have frequent admissions for respiratory illness requiring intravenous antibiotics. Placement of peripherally inserted central cannulae allows discharge earlier to the home, and community management. Where peripherally inserted central cannulae access is no longer possible or acceptable to the family, implantable vascular access devices can spare children multiple distressing attempts at peripheral cannulation and facilitate treatment of infections at home. This appears to be safe and effective in children with CF though complications may occur at the time of insertion or later, including pneumothorax, thrombosis, embolism, infection and occlusion.w15
Children with severe neurological impairment should receive all of the routine childhood immunisations, remembering that preterm babies should be vaccinated at the appropriate chronological age and not the corrected gestational age, and that live vaccines should be deferred in the immunosuppressed.w7 These children should also receive the 23-valent pneumococcal vaccine after their second birthday, which is distinct from the routine UK immunisation schedule.w7
Kyphoscoliosis and postural management
Abnormal posture caused by kyphoscoliosis negatively impacts on respiratory function, eventually causing a restrictive disease lung pattern. Postural management using special seating systems or surgery can improve posture. Some studies link these two observations and show an improvement in lung function with postural management in children with neurological disorders, although there are no RCTs supporting this. Care must be taken in children with diaphragmatic weakness, as seating and rigid bracing may worsen their lung function.w16 If surgery is considered, preoperative assessment and the support of paediatric intensive care facilities are essential. Postoperative ventilation, which may be prolonged, is more likely to be required in those with significant bulbar dysfunction and in those who have experienced recurrent admission with chest infections.
Chest physiotherapy is widely used for children with severe neurological impairment and frequent respiratory illness, either regularly or during acute illness.9 There is unfortunately little evidence on the efficacy of this practice in the literature. In fact, there is no evidence to support the use of physiotherapy in otherwise healthy children with community acquired pneumonia, and it is specifically discouraged in the relevant British Thoracic Society guideline. However, children with neurological impairment and frequent chest infections have difficulty clearing infected secretions from their chests. They thus have more in common with children with neuromuscular weakness, in whom chest physiotherapy is felt to be a crucial part of the management of acute infection.w16 Families may also want to perform physiotherapy at home during minor illnesses, and we feel this should be considered. Equipment for airway suctioning and administration of nebulised agents to facilitate airway clearance may also be needed. Anecdotally, bronchodilators such as salbutamol and agents to help induce expectoration such as saline or hypertonic saline are often used during chest physiotherapy. The use of cough assist devices in those with weak cough or during acute illness is also an area that requires further study in this population. The multidisciplinary approach to annual review of chest management is summarised in table 2.
Home oxygen, invasive and non-invasive ventilation
Progressive decline in respiratory function may be a feature of some children with severe neurological impairment. At oxygen saturations below 90% (which correlates with approximately 60 mm Hg alveolar oxygen pressure), pulmonary artery pressures begin to rise.w17 This may have an adverse effect on the function of the heart. Home therapy with oxygen is sometimes therefore helpful in allowing a child to remain in the home either during intercurrent infection, or where the consequences of chronic lung disease secondary to complications of severe neurological impairment have occurred. The ability to measure oxygen saturations either intermittently or continuously may be available to caregivers in this situation. Intermittent oxygen therapy to treat seizures is not recommended.w18
As previously mentioned, overnight CPAP may improve daytime alertness and quality of life in children with neurological impairment. A small but increasing number of children are on long-term ventilation.w19 Non-invasive support via facemask, or invasive ventilatory support via tracheostomy may offer the theoretical opportunity to recruit atelectatic lung, optimise functional residual capacity to improve mechanical advantage during breathing and increase the partial pressure of oxygen. However positive pressure devices may be uncomfortable, interfere with sleep, promote aspiration where bulbar function is poor and cause skin breakdown. Evidence about how it may be helpful for children with severe neurological impairment is not yet available. A Cochrane review of adults with motor neuron disease showed that those with severe bulbar dysfunction reported no improvement in their quality of life.w20 Outpatient management of home ventilation requires an experienced multidisciplinary team and motivated and capable carers in the home. For many children the imposition it creates for their lives is not outweighed by the benefits they receive and paediatricians should be ready to recognise that situation.
Other modifiable considerations: epilepsy control
Epilepsy is commonly associated with severe neurological impairment and seizure control may affect respiratory function through a number of mechanisms. Seizures may be associated with tachypnoea, respiratory pauses or hypoxia. Temporal lobe seizures in particular cause significant hypoxia. In one study 40% of these seizures were associated with significant transient hypoxia and 70% with respiratory pauses.w21 The risk of aspiration may be increased with the reduction of upper airway protective reflexes especially in those with pre-existing abnormalities of tone and co-ordination. On the other hand, airway protection may be adversely affected by the sedating side effects of some anticonvulsant regimes. Benzodiazepines used in status epilepticus have been associated with an incidence of significant respiratory depression in 5.5% of children.w22 Balancing an individual child's anticonvulsant regime against optimal respiration function requires experience and flexibility as circumstances change.
Palliative care and advanced planning
Honest discussions about prognosis and how far treatment should go in the event of deterioration should take place within the trusting relationship between the family and their medical team. It is important to have these discussions in advance, revisiting them as often as the family needs and as the child's condition dictates.9 ,11 Framing these discussions in a family-held personal resuscitation plan is a positive step, which can empower parents and guide medical staff.w23
A paediatric palliative care team can provide invaluable support in symptom control and maximising quality of life. At the end of life the helpfulness of oxygen for the control of breathlessness is variable and for many its beneficial effect is limited.w24 Studies indicate that the use of low-dose opioids is more effective in the treatment of distressing respiratory symptoms, alongside the other treatments mentioned, and is unlikely to cause respiratory depression if titrated carefully.11 w16
Throughout our review of the available literature it is clear that there are still insufficient randomised studies to inform the treatment of respiratory disease in children with severe neurological impairment. Clinicians balance complex medical and family circumstances unique to the child. When considering an individual child's needs, aspects of respiratory function related to anatomical site, muscular weakness and infection, can be addressed in a structured way. Complications such as kyphoscoliosis and malnutrition require anticipation and the active involvement of a motivated multidisciplinary team. New therapies and access to more acceptable ways of delivering non-invasive ventilation may improve quality of life in selected groups. Blending life-sustaining respiratory treatments with those that maximise comfort and enjoyment for the child is a human challenge as well as an intellectual one.
Contributors RB had the original idea for the article and contributed to the writing and editing of the final draft. NM carried out the literature search, wrote the first draft and contributed to the editing of the final draft. RO contributed to the writing and editing of the final draft.
Competing interests None.
Provenance and peer review Commissioned; externally peer reviewed.