Katherine Langdon

Effectiveness of sedation using nitrous oxide compared with enteral midazolam for botulinum toxin A injections in children

SIR–Zier et al. published their randomized, double-blind, placebo-controlled study comparing the efficacy of enteral midazolam with inhaled nitrous oxide (N2O) in children undergoing botulinum toxin A (BoNT-A) injections in an outpatient setting. They concluded that N2O conferred a level of procedural sedation at least as effective as enteral midazolam but that N2O had a superior analgesic effect. We would like to draw your attention to the results of two audits conducted within the Cerebral Palsy Mobility Service at Princess Margaret Hospital for Children that evaluated the safety and efficacy of midazolam and two further premedication agents, with analgesic properties, for children undergoing BoNT-A injections. Approximately 600 BoNT-A treatment episodes are provided each year by the Cerebral Palsy Mobility Service and these audits were conducted with the aim of refining the sedation and analgesia for the patients undergoing BoNT-A treatment and confirming the safety of these medications in this group of patients. These audits were approved by the Princess Margaret Hospital as part of the quality assurance activities by the Department of Paediatric Rehabilitation Unit. The first audit, which was presented as a poster at a meeting of the Australian Academy of Cerebral Palsy and Developmental Medicine (Aus ACPDM) in 2004, evaluated the use of oral midazolam alone and a midazolam-ketamine combination (MIKE) as premedication for children undergoing BoNT-A injections. MIKE was used in children where midazolam had previously been unsatisfactory, or numerous injections were planned. All children were also given topical anaesthetic cream. A total of 105 children (72 males, 33 females; mean age 7y 1mo [SD 3y 11mo]) received midazolam (0.5mg ⁄ kg maximal dose 12mg) and 18 children (five males, 13 females) were given MIKE (midazolam 0.5mg ⁄ kg ketamine 3mg ⁄ kg orally). In the midazolam alone group, 89.5% tolerated the procedure well with 85% of parents reporting satisfaction with the level of their child’s sedation and ability to tolerate the procedure. In the ‘more difficult’ group of 18 children that received MIKE, 12 subsequently tolerated the procedure adequately. Eleven children in this group had previously undergone BoNT-A with midazolam alone, and eight of the children’s parents felt the procedure was better tolerated with MIKE than midazolam alone. There was one minor adverse effect involving transient distress post-procedure. Following this, a second audit (which was presented as a platform presentation at the Aus ACPDM meeting in 2008) was conducted to establish the safety and efficacy of intranasal fentanyl (plus topical anaesthetic cream) in children with cerebral palsy receiving BoNT-A. Fentanyl administered via the intranasal route provides an analgesic effect within 5 to 10 minutes and is non-sedating. A cohort of 108 children (62 males, 46 females; mean age 8y 11mo [SD 3y 11mo]) with cerebral palsy (Gross Motor Function Classification System level I n=63, level II n=30, level III n=15; the majority having spastic diplegia without significant involvement of the upper limbs) received fentanyl (1.5micrograms ⁄ kg to a maximal dose of 75micrograms) before being injected with BoNT-A. No serious adverse event was recorded. Overall, 81 of the 108 parents reported that intranasal fentanyl was superior to their child’s previous method of conscious sedation. However it was notable that the observed analgesic effect of intranasal fentanyl was superior in heavier (>20kg) children. The lack of sedation was novel to our population, already accustomed to premedication with midazolam and MIKE. This provided an opportunity to exploit distraction techniques during the procedure. In younger and more anxious children, some sedation can be advantageous although in our experience, if the analgesia is effective, anxiety generally resolves as the procedure progresses. Intranasal fentanyl also allows for easy positioning of the patient and rapid discharge at the completion of the procedure. We are increasingly using intranasal fentanyl with topical anaesthetic cream as a premedicant for children receiving BoNT-A in preference to midazolam because it confers less sedation, better analgesia, ease of administration, and the convenience of rapid discharge. Better access to procedural anaesthesia for BoNT-A has largely obviated the use of MIKE, however, this remained in use in a select group of patients until 2007. In the 12 months to April 2008, approximately one-third of our BoNT-A patients received general anaesthesia, one-third intranasal fentanyl, and the remainder either midazolam alone, MIKE, or local anaesthetic cream alone. We agree that providing adequate analgesia during the administration of BoNT-A is important with most children

The prevalence of mental health disorders and symptoms in children and adolescents with cerebral palsy: a systematic review and meta-analysis

Mental health conditions and problems are often reported in children and adolescents with cerebral palsy (CP). A systematic review was undertaken to describe their prevalence.

Adverse events following botulinum toxin type A treatment in children with cerebral palsy

SIR–We read with utmost interest the article by Naidu et al. on systemic adverse events following botulinum toxin A (BoNT-A) therapy in children with cerebral palsy. The authors report on the incidence of bladder and bowel incontinence and respiratory symptoms after BoNT-A injections (1980 episodes) in the lower limbs of 1147 children with various types of cerebral palsy. They found that the incidence of (serious) adverse events was low, with 16 episodes of incontinence of the bowel, representing about 1% of all injection episodes. However, they did not report a single episode of constipation as an adverse event in their large group of patients. Recently, we published a case report on three patients who developed transient constipation after receiving therapeutic doses of BoNT-A to treat spasticity of the lower limbs (two patients) and the upper limbs (one patient). Constipation was observed within the first week after treatment. In all three cases this symptom resolved completely and almost simultaneously with disappearance of the therapeutic effects of BoNT-A on mobility. This course is similar to that described in the cases of incontinence. Two patients received a second treatment and both presented the same autonomic cholinergic remote symptoms. The third patient refused a second treatment because of the earlier complication. As the colon is not in close proximity to the injection sites, the constipation is most probably caused by a systemic effect of BoNT-A. This presumption was made even more likely after electromyography (EMG) of the hypothenar muscles while stimulating the ulnar nerve at the wrist. The EMG showed that fewer muscle fibres responded to nerve stimulation during a train of stimuli, pointing to a generalized blockage of acetylcholine release in nerve terminals (Fig. SI; supporting information available online). Familiarity with this autonomic systemic adverse event of BoNT-A is essential for those who treat patients already at risk for gastrointestinal dysfunction. Because the adverse effects were treatable and transitory, we believe that constipation per se is not an absolute contraindication if, from a therapeutic point of view, BoNT-A is indicated.

Prevalence of symptoms associated with respiratory illness in children and young people with cerebral palsy

1 Therapy and Health Services, Ability Centre, Mount Lawley, WA; 2 Physiotherapy, Princess Margaret Hospital for Children, Perth, WA; 3 Telethon Kids Institute, The University of Western Australia, Perth, WA; 4 Paediatric Rehabilitation, Princess Margaret Hospital for Children, Perth, WA; 5 Perth Children’s Hospital Project, Princess Margaret Hospital for Children, Perth, WA; 6 Respiratory Medicine, Princess Margaret Hospital for Children, Perth, WA; 7 School of Paediatrics and Child Health, The University of Western Australia, Perth, WA, Australia.

Sleep concerns in children and young people with cerebral palsy in their home setting

The aims were to identify in‐home concerns about sleep in children and young people with cerebral palsy (CP) across age and Gross Motor Function Classification Scale (GMFCS) levels.

Patterns and reliability of children's skin temperature prior to and during sleep in the home setting

The relationship between patterns of change in skin temperature and sleep is well recognized. In particular, there is a rapid rise in distal skin temperature (Tdistal) and slower rise in proximal skin temperature (Tproximal) prior to sleep onset. The difference between Tdistal and Tproximal is known as the distal-proximal gradient (DPG). Rise in DPG is known as a measure of distal vasodilation, which contributes to the drop in core body temperature (Tcore) that is important to sleep onset and maintenance. Patterns of change in skin temperature before and during sleep are reported for neonates, infants, adults and elderly, however they are not known for school aged children. Therefore, the current observational study aimed to determine the patterns and reliability of skin temperatures (Tskin) and DPG in relation to sleep of school aged children in their home settings. Participants (22 children, aged 6-12) completed the Childrens Sleep Habits Questionnaire and used Thermochron iButtons and actigraphy for four school nights in their typical sleep settings. There were evident patterns of Tskin change before and during sleep. In particular, Tdistal was lower but rose more rapidly than Tproximal after reported bedtime and prior to sleep onset. This reflected a timely rise in DPG, and shows that distal vasodilation precedes sleep onset in school aged children. The measures of Tskin and sleep were practical for children in their home settings, and the observed patterns were consistent across consecutive school nights. Environmental and behavioural strategies that manage skin temperature before and during sleep should be explored for their potential as valuable components of treatment of childhood insomnia.

MP56-16 EFFICACY AND SAFETY OF TRANSDERMAL OXYBUTYNIN VERSUS ORAL OXYBUTYNIN IN THE MANAGEMENT OF PEDIATRIC NEUROGENIC BLADDER

Anticholinergic medications are the gold standard in pharmacotherapy for neurogenic bladder. The first line agent in Australia is oxybutynin due to cost and accessibility. Oxybutynin is available in both oral and transdermal forms. Oral oxybutynin can be associated with a significant side effect profile in some children. Additionally, compliance may be poor with oral medication due to difficulty in taking tablets in addition to inability to tolerate associated side effects. Transdermal formulations have the potential advantage of ease of use resulting in increased compliance and reduced systemic side effects. effects. CONCLUSIONS

Predicting respiratory hospital admissions in young people with cerebral palsy

Objective To determine the early predictors of respiratory hospital admissions in young people with cerebral palsy (CP). Design A 3-year prospective cohort study using linked data. Patients Children and young people with CP, aged 1 to 26 years. Main outcome measures Self-reported and carer-reported respiratory symptoms were linked to respiratory hospital admissions (as defined by the International Statistical Classification of Diseases and Related Health Problems 10th Revision codes) during the following 3 years. Results 482 participants (including 289 males) were recruited. They were aged 1 to 26 years (mean 10 years, 10 months; SD 5 years, 11 months) at the commencement of the study, and represented all Gross Motor Function Classification Scale (GMFCS) levels. During the 3-year period, 55 (11.4%) participants had a total of 186 respiratory hospital admissions, and spent a total of 1475 days in hospital. Statistically significant risk factors for subsequent respiratory hospital admissions over 3 years in univariate analyses were GMFCS level V, at least one respiratory hospital admission in the year preceding the survey, oropharyngeal dysphagia, seizures, frequent respiratory symptoms, gastro-oesophageal reflux disease, at least two courses of antibiotics in the year preceding the survey, mealtime respiratory symptoms and nightly snoring. Conclusions Most risk factors for respiratory hospital admissions are potentially modifiable. Early identification of oropharyngeal dysphagia and the management of seizures may help prevent serious respiratory illness. One respiratory hospital admission should trigger further evaluation and management to prevent subsequent respiratory illness.