Botulinum Toxin: Techniques Within Pediatric Physiatry

Adverse events after chemodenervation with onabotulinum neurotoxin A in children with hypertonia and sialorrhea

AIM

To identify the incidence and type of adverse events reported after chemodenervation with onabotulinum neurotoxin A (BoNT-A) in children with hypertonia and sialorrhea and compare adverse events in the on-label or off-label use of BoNT-A with regard to dose, patient's age, and location of the injection.

METHOD

Using a retrospective chart review, we studied BoNT-A injections occurring from January 2017 to December 2020 in patients at a pediatric hospital. The electronic health record was examined to identify adverse events reported within 2 months of the injection. Data included the patient's age, sex, race, and ethnicity, as well as the type of toxin injected, the dose, the location of injection, and the patient's weight.

RESULTS

We analyzed 1733 procedures. Adverse events were infrequent (2.5%) and not serious, most commonly reported as pain or discomfort. All adverse events were temporary and there were no deaths. We did not observe a meaningful difference in the frequency of adverse events for injections that exceeded the 2022 US Food and Drug Administration (FDA)-approved maximum dose compared to injections that were within the FDA-approved dose range. The likelihood of adverse events did not increase with higher doses of BoNT-A. More adverse events were reported for injection into the salivary glands (4.37%) than into the extremities (2.26%).

INTERPRETATION

Higher doses of injected BoNT-A in a pediatric population may be safe. Further work is needed to investigate the relationship between dose and efficacy.

First year impacts of the COVID-19 pandemic on pediatric physiatrists

PURPOSE

The objective of this study was to determine how the COVID-19 pandemic impacted the work and compensation of pediatric physiatrists during the first year of the pandemic.

METHODS

Pediatric physiatrists were surveyed in the spring of 2021 about how the first year of the COVID-19 pandemic impacted their practices as a part of a larger survey examining pediatric rehabilitation medicine practices. The COVID-19 specific questions covered three topic areas: 1) personal experiences with COVID-19; 2) occupational workflow changes due to COVID-19, including telehealth; and 3) employment consequences of the COVID-19 pandemic.

RESULTS

Thirteen of 259 pediatric physiatrists reported having a COVID-19 infection, of whom none required hospitalization. Nearly all (96.5%) of pediatric physiatrists reported using telehealth during the pandemic compared to 14% prior to the pandemic. They reported numerous changes to their clinical operations, and 50% reported not having adequate personal protective equipment available for themselves or their staff all of the time. Fifteen pediatric physiatrists (5.9%) reported being furloughed, and three reported job loss during the first year of the pandemic.

CONCLUSION

While only a small percentage of pediatric physiatrists contracted COVID-19 during the first year of the pandemic, nearly all experienced workflow changes.

Current Australian clinical practice in use of botulinum toxin-A to manage paediatric hypertonicity

AIM

To describe current rehabilitation paediatricians' use of intramuscular botulinum toxin-A (BoNT-A) to manage hypertonicity.

METHODS

Cross-sectional survey.

RESULTS

In late 2019, 32 of the 35 identified Australian rehabilitation paediatricians who use BoNT-A to manage paediatric hypertonicity completed the survey. Annually, they administer just over 3750 courses of BoNT-A to manage hypertonicity with a mean of 11 years of clinical experience. Sedation was used by all but 1 clinician who used a number of other strategies during the procedure. Mean (and median) maximum dose of OnabotulinumtoxinA (Botox) was 400 Units (range 300-450 Units). Only three clinicians indicated that they used AbobotulinumtoxinA (Dysport) - the other BoNT-A preparation approved for children available in Australia; analysis of its use was not performed. Dose modifications were made by clinicians according to a patient's response to a previous course of BoNT-A (88% of respondents); patient experience of a previous adverse event (78%); history of aspiration or dysphagia (65 and 63%, respectively); and the presence of dystonia; and where the patient was GMFCS level V (53% each). Intervals between courses ranged from 3 to 24 months with the variation due to clinical circumstances.

CONCLUSION

Clinical practice in BoNT-A management of paediatric hypertonicity was largely consistent in regard to maximum doses of OnabotulinumtoxinA (Botox) used. Dose modification and time between injection courses varied according to individual clinical presentation. Procedural sedation was used extensively.

A consensus statement on the use of botulinum toxin in pediatric patients

Botulinum toxin has been used in medicine for the past 30 years. However, there continues to be controversy about the appropriate uses and dosing, especially in the pediatric population. A panel of nine pediatric physiatrists from different regions and previous training programs in the United States were nominated based on institutional reputation and botulinum toxin (BoNT) experience. Based on a review of the current literature, the goal was to provide the rationale for recommendations on the administration of BoNT in the pediatric population. The goal was not only to review safety, dosing, and injection techniques but also to develop a consensus on the appropriate uses in the pediatric population. In addition to upper and lower limb spasticity, the consensus also provides recommendations for congenital muscular torticollis, cervical dystonia, sialorrhea, and brachial plexus palsies.

Assessments and Interventions for Spasticity in Infants With or at High Risk for Cerebral Palsy: A Systematic Review

BACKGROUND

The majority of children with cerebral palsy develop spasticity, which interferes with motor development, function, and participation. This systematic review appraised current evidence regarding assessments and interventions for spasticity in children aged less than two years with or at high risk for cerebral palsy and integrated findings with parent preferences.

METHODS

Five databases (CINAHL, EMBASE, OVID/Medline, SCOPUS, and PsycINFO) were searched. Included articles were screened using PRISMA guidelines. Quality of the evidence was reviewed by two independent reviewers using Quality Assessment of Diagnostic Accuracy Studies, second edition (QUADAS-2), the RTI Item Bank on Risk of Bias and Precision of Observational Studies (RTI), or The Cochrane Collaboration's tool for assessing risk of bias in randomized trials (RoB). An online survey was conducted regarding parent preferences through social media channels.

RESULTS

Twelve articles met inclusion criteria. No high-quality assessment tool emerged for this population. Six interventions (botulinum toxin-A, orthotic use, radial extracorporeal shock wave therapy, erythropoietic stimulating agents, medical cannabis, and homeopathy) were identified. There was low-quality evidence for the use of botulinum toxin-A and radial extracorporeal shock wave therapy to improve short-term outcomes. Survey respondents indicated that spasticity assessments and interventions are highly valued, with nonpharmacologic interventions ranked most preferably.

CONCLUSIONS

Further research is needed to validate assessments for spasticity in children younger than two years. Conditional recommendations can be made for botulinum toxin-A and radial extracorporeal shock wave therapy based on low level of evidence to reduce spasticity in children aged less than two years.

A risk-stratified approach toward safely resuming OnabotulinumtoxinA injections based on dosing and ambulatory status in pediatric patients with cerebral palsy during the Coronavirus pandemic of 2019 (COVID-19)

PURPOSE

After the onset of the Coronavirus pandemic of 2019-2020 (COVID-19), physicians who inject OnabotulinumtoxinA (BoNT-A) were left with determining risks and benefits in pediatric patients with cerebral palsy. Many of these patients have pre-existing conditions that make them more prone to COVID-19 symptoms, and this susceptibility potentially increases after BoNT-A injections.

METHODS

A retrospective chart review of 500 patients identified 256 pediatric patients with cerebral palsy who received an intramuscular BoNT-A injection to determine relative doses used for each Gross Motor Functional Classification Score (GMFCS). Data regarding age, weight, GMFCS, BoNT-A total body dosage, and inpatient hospitalizations for 6 months post-injection were collected. Differences between GMFCS levels were analyzed using one-way analysis of variance testing. Inpatient hospitalizations were recorded and assessed using relative risk to determine the population risk of hospitalization in the setting of initiating injections during the COVID-19 pandemic.

RESULTS

Based on GMFCS level, patients who were GMFCS I or II received fewer units of BoNT-A medication per kilogram of body weight compared to GMFCS III-V (p< 0.0005, F= 25.38). There was no statistically significant difference in frequency or time to hospitalization when comparing patients receiving BoNT-A compared to a control group.

CONCLUSIONS

Resumption of BoNT-A injections during the time of COVID-19 requires a systematic approach based on risks and potential benefits. Data from this analysis does not show increased risk for patients who received injections historically; however, recommendations for resumption of injections has not previously been proposed in the setting of a pandemic. In this manuscript, a tiered approach to considerations for injections was proposed. Botulinum toxin type A injections have a history of improving spasticity in the pediatric patient with cerebral palsy. Ensuring appropriate selection of patients for injection with BoNT-A during this pandemic is increasingly important.

A pragmatic approach to Botulinum Toxin safety

Botulinum Toxin (BoNT) is widely used to treat hypertonia in pediatric patients. Although serious adverse events (AEs) occur infrequently, they can lead to significant patient morbidity and mortality. This paper will discuss potential safety risks that may affect outcomes, medical comorbidities, medication dosing, targeting techniques, and muscle morphology. It is the responsibility of the physician to discuss risks and benefits regarding the use of BoNT and mitigate risks of AEs while maximizing the effectiveness of the medication.