Outpatient Procedural Sedation of Patients With Autism Spectrum Disorders for Magnetic Resonance Imaging of the Brain Using Propofol

Neurophysiological measures and correlates of cognitive load in attention-deficit/hyperactivity disorder (ADHD), autism spectrum disorder (ASD) and dyslexia: A scoping review and research recommendations

Working memory is integral to a range of critical cognitive functions such as reasoning and decision-making. Although alterations in working memory have been observed in neurodivergent populations, there has been no review mapping how cognitive load is measured in common neurodevelopmental conditions such as attention-deficit/hyperactivity disorder (ADHD), autism spectrum disorder (ASD) and dyslexia. This scoping review explores the neurophysiological measures used to study cognitive load in these specific populations. Our findings highlight that electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) are the most frequently used methods, with a limited number of studies employing functional near-infrared spectroscopy (fNIRs), magnetoencephalography (MEG) or eye-tracking. Notably, eye-related measures are less commonly used, despite their prominence in cognitive load research among neurotypical individuals. The review also highlights potential correlates of cognitive load, such as neural oscillations in the theta and alpha ranges for EEG studies, blood oxygenation level-dependent (BOLD) responses in lateral and medial frontal brain regions for fMRI and fNIRS studies and eye-related measures such as pupil dilation and blink rate. Finally, critical issues for future studies are discussed, including the technical challenges associated with multimodal approaches, the possible impact of atypical features on cognitive load measures and balancing data richness with participant well-being. These insights contribute to a more nuanced understanding of cognitive load measurement in neurodivergent populations and point to important methodological considerations for future neuroscientific research in this area.

Strategies to improve the magnetic resonance imaging experience for autistic individuals: a cross-sectional study exploring parents and carers' experiences

BACKGROUND

Autistic individuals encounter numerous barriers in accessing healthcare, including communication difficulties, sensory sensitivities, and a lack of appropriate adjustments. These issues are particularly acute during MRI scans, which involve confined spaces, loud noises, and the necessity to remain still. There remains no unified approach to preparing autistic individuals for MRI procedures.

METHODS

A cross-sectional online survey was conducted with parents and carers of autistic individuals in the UK to explore their experiences, barriers, and recommendations concerning MRI scans. The survey collected demographic information and experiential accounts of previous MRI procedures. Quantitative data were analysed descriptively, while key themes were identified within the qualitative data through inductive thematic analysis.

RESULTS

Sixteen parents/carers participated. The majority reported difficulties with communication, inadequate pre-scan preparation, and insufficient adjustments during MRI scans for their autistic children. Key barriers included an overwhelming sensory environment, radiographers' limited understanding of autism, and anxiety stemming from uncertainties about the procedure. Recommended improvements encompassed accessible communication, pre-visit familiarisation, noise-reduction and sensory adaptations, staff training on autism, and greater flexibility to meet individual needs.

CONCLUSIONS

There is an urgent need to enhance MRI experiences for autistic individuals. This can be achieved through improved staff knowledge, effective communication strategies, thorough pre-scan preparation, and tailored reasonable adjustments. Co-producing clear MRI guidelines with the autism community could standardise sensitive practices. An individualised approach is crucial for reducing anxiety and facilitating participation. Empowering radiographers through autism-specific education and incorporating insights from autistic individuals and their families could transform MRI experiences and outcomes.

Pediatric Sedation/Anesthesia for MRI: Results From the Pediatric Sedation Research Consortium

BACKGROUND

Magnetic resonance imaging (MRI) is the most common imaging procedure requiring sedation/anesthesia in children. Understanding adverse events associated with sedation/anesthesia is important in making decisions regarding MRI vs. other imaging modalities. No large studies have evaluated the practice of pediatric sedation/anesthesia for MRI by a variety of pediatric specialists.

PURPOSE

Utilize a large pediatric sedation database to characterize the patients and adverse events associated with sedation/anesthesia for pediatric MRI.

STUDY TYPE

Retrospective analysis of prospectively collected data.

SUBJECTS

The Pediatric Sedation Research Consortium (PSRC) has 109,947 entries for sedations for MRI from November 10, 2011 through December 18, 2017.

ASSESSMENT

Patient demographics, sedative medications, interventions, and adverse events are described. Associations with adverse events were assessed. Trends in sedative medications used over time are examined.

STATISTICAL TESTS

Descriptive statistics, Chi-Squared and Fisher's Exact tests for categorical variables, logistic regression and assessment of trend using logistic regression and other method.

RESULTS

A total of 109,947 MRI-related sedations were examined. Most subjects (66.2%) were 5 years old or younger. Seizure or other neurologic issue prompted MRI in 63.7% of cases. Providers responsible for sedation/anesthesia included intensivists (49.3%), emergency medicine physicians (28.2%), hospitalists (10.2%), and anesthesiologists (9.8%). The most commonly used sedative agent was propofol (89.1%). The most common airway intervention was supplemental oxygen (71.7%), followed by head/airway repositioning (20.6%). Airway-related adverse events occurred in 8.4% of patients. Serious adverse events occurred in only 0.06% of patients, including three cases of cardiac arrest. No mortality was recorded. There was a statistically significant increase in the use of dexmedetomidine over time.

DATA CONCLUSIONS

Overall, adverse event rates were low. Sedation/anesthesia with propofol infusion and natural airway was the most common method used by this varied group of sedation providers. The use of dexmedetomidine increased over time.

EVIDENCE LEVEL

4 TECHNICAL EFFICACY: Stage 5.

A systematic review of person-centred adjustments to facilitate magnetic resonance imaging for autistic patients without the use of sedation or anaesthesia

LAY ABSTRACT

Autistic patients often undergo magnetic resonance imaging examinations. Within this environment, it is usual to feel anxious and overwhelmed by noises, lights or other people. The narrow scanners, the loud noises and the long examination time can easily cause panic attacks. This review aims to identify any adaptations for autistic individuals to have a magnetic resonance imaging scan without sedation or anaesthesia. Out of 4442 articles screened, 53 more relevant were evaluated and 21 were finally included in this study. Customising communication, different techniques to improve the environment, using technology for familiarisation and distraction have been used in previous studies. The results of this study can be used to make suggestions on how to improve magnetic resonance imaging practice and the autistic patient experience. They can also be used to create training for the healthcare professionals using the magnetic resonance imaging scanners.

Procedural sedation in children with autism spectrum disorders in the emergency department

BACKGROUND AND OBJECTIVES

Children with autism spectrum disorder (ASD) present more frequently to the emergency department (ED) than children with normal development, and frequently have injuries requiring procedural sedation. Our objective was to describe sedation practice and outcomes in children with ASD in the ED.

METHODS

We performed a retrospective chart review of children with ASD who underwent sedation at two tertiary care EDs between January 2009-December 2016. Data were collected on children 1-18 years of age with ASD who were sedated in the ED.

RESULTS

There were 6020 ED visits by children with ASD, 126 (2.1%) of whom received sedation. The most frequent indications for sedation were laceration repair (24.6%), incision and drainage (17.5%), diagnostic imaging (14.3%), and physical examination (11.9%). The most common sedatives used were ketamine (50.8%) and midazolam (50.8%). Ketamine was most commonly given intravenously (71.9%), while midazolam was usually given intranasally (71.9%). Procedures could not be completed in 4 (3.2%) patients, and adverse events were noted in 23 (18.3%) patients. Only four (3.2%) patients required supplemental oxygenation, and one received positive pressure ventilation.

CONCLUSIONS

Children with autism in the ED commonly received sedation; one in four of which were for non-painful diagnostic procedures or physical examination. Over one-third received sedation via a non-parenteral route for intended minimal sedation. Sedative medication dosing and observed adverse events were similar to those reported previously in children without ASD. Emergency providers must be prepared to meet the unique sedation needs of children with ASD.