Negative effects of submandibular botulinum neurotoxin A injections on oral motor function in children with drooling due to central nervous system disorders

Abstract

AIM The aims of this study were: (1) to determine the incidence and nature of adverse effects on oral motor function after first injections of botulinum neurotoxin A (BoNT-A) in submandibular glands for excessive drooling in children with central nervous system disorders; and (2) to identify independent predictors of these adverse effects.METHOD A cohort study involved 209 children (123 males, 86 females, aged 4-27y, median 8y 4mo), who received submandibular BoNT-A injections for drooling. Adverse effects were categorized into swallowing, eating, drinking, articulation, and other problems. Univariable logistic regression was used to study differences in patients with and without adverse effects. Possible predictors were identified using multivariable logistic regression.RESULTS Transient adverse effects occurred in 33% of the 209 BoNT-A treatments. Almost 80% of these were mild, versus 8.7% severe. Approximately 54% of the adverse effects spontaneously resolved within 4 weeks; 3% still existed after 32 weeks. A diagnosis of cerebral palsy, higher range of BoNT-A dosage, and a pre-treatment drooling quotient <18% were found to be independent predictors of adverse effects.INTERPRETATION Before using submandibular BoNT-A injections for drooling, potential adverse effects should be discussed. Oral motor function needs to be monitored, because existing dysphagia may be worsened. The identified clinical predictors could be helpful to optimize patient selection.Treatment with botulinum neurotoxin (BoNT) in the salivary glands is a widely accepted effective intervention for drooling in children with central nervous system (CNS) disorders. When injected into the salivary glands, BoNT inhibits the acetylcholine release at the terminal nerve endings, decreasing the secretion of saliva and diminishes drooling in the majority of patients. 1The main group of children with neurological impairments treated with BoNT injections are children with cerebral palsy (CP), a vulnerable group with a spectrum of oral motor problems (estimated 40% drooling prevalence).2-4 Drooling has a serious impact on the children's social interaction, self-esteem, and health. 5 The effectiveness of salivary gland BoNT has been studied extensively, although the debate about which glands should be injected is still going on. Several studies demonstrated that, after BoNT, drooling is significantly reduced. In Scheffer's study a clinically notable response was found in 46.6% of children. 6 The duration of this effect was approximately 2 to 6 months (median 24wks). [6][7][8] In most of these studies, botulinum neurotoxin A (BoNT-A) was used. 9Considering the increasing use of BoNT for drooling, studies to identify possible risk factors for adverse effects on oral motor functions before treatment are urgently needed. 10Post-intervention assessments showed that adverse effects on oral motor functions with a potential negative effect on swallowing occurred from 0% 11-13 up to 17.8% 6 of the cases after submandibular gland injections, and up to 33% 14 of the ...

Submandibular duct ligation after botulinum neurotoxin A treatment of drooling in children with cerebral palsy

“…Both procedures were performed as part of day care. BoNT‐A (Botox; Allergan, Dublin, Republic of Ireland) was administered under general anaesthesia, fractioning 1ml over two or three sites throughout the submandibular gland using a Spinocan needle and ultrasound guidance …”

Respiratory morbidity in children with cerebral palsy: an overview

“…BoNT‐A injection in the salivary glands has been said to be effective in reducing respiratory problems in patients with neurological impairment, but further evidence is needed . It should also be taken into account that BoNT‐A injection in the salivary glands can be associated with mild and transient oral motor problems, especially in patients with CP, those with mild drooling before treatment, or if a high dose of BoNT‐A is used . Data about surgical treatments are conflicting.…”

“…23,24 It should also be taken into account that BoNT-A injection in the salivary glands can be associated with mild and transient oral motor problems, especially in patients with CP, those with mild drooling before treatment, or if a high dose of BoNT-A is used. 25 Data about surgical treatments are conflicting. Some authors reported that surgical saliva reduction was effective in What this paper adds • Respiratory problems are a significant cause of morbidity in patients with cerebral palsy (CP).…”

The whole truth about botulinum toxin – a review

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“…Cyclosporine can induce muscle weakness secondary to neuromuscular blockade, and can lead to respiratory failure. Discontinuing therapy with these drugs or a short cessation is recommended to avoid potential botulinum toxin-related side effects [35][36][37].…”