Specific Aim 1: To describe the adequacy of sedation associated with different regimens of IN DEX in children undergoing non-painful procedures. This aim will test the working hypothesis that IN DEX regimens are effective for producing sedation adequate for completion of non-painful procedures in children.

Specific Aim 2: To describe the temporal characteristics associated with varied regimens of IN DEX in children undergoing non-painful procedures, such as time to onset of adequate sedation; time to procedure start; and time from procedure end to meeting discharge criteria. This aim will test the working hypothesis that IN DEX regimens have temporal characteristics that are favourable for sedating children for non-painful procedures.

Specific Aim 3: To describe the adverse events associated with varied regimens of IN DEX in children undergoing non-painful procedures. This aim will test the working hypothesis that IN DEX regimens have a low incidence of adverse events.

Dexmedetomidine (DEX) is an alpha-2 receptor agonist with sedative, anxiolytic, and analgesics properties. DEX has been used extensively for sedation in children to facilitate different non-painful procedures, such magnetic resonance imaging (MRI), auditory brainstem response (ABR) tests, and computed tomography (CT) scans. In particular, DEX can be administered by the intranasal (IN) route. Intranasal administration has the benefits of being both effective and needle-free, of which the latter makes it less distressing to children compared to sedatives administered by the intravenous (IV) route. There is a gap of knowledge, however, regarding the ideal regimen of IN DEX for providing optimal procedural sedation in children undergoing non-painful procedures. There is a large variation in practice using IN DEX, both regarding the dose and the use of adjunct medications. It is also unknown whether regimens should vary based on patient factors such as age. There is no clear evidence to define best practice when using IN DEX to provide sedation in this population to achieve the desired outcomes most relevant to clinicians. The rationale of the proposed investigation is that by conducting an exploratory study to measure clinical outcomes associated with IN DEX, the investigators can begin to identify trends and differences that will lay the foundation for randomized clinical trials to identify the ideal regimen for IN DEX when providing sedation for non-painful procedures. This will then allow the investigators to compare IN DEX, at its best, to other sedatives so that the sedative and regimen associated with the best outcomes relevant to sedation of children undergoing non-painful procedures can be determined.

Inclusion Criteria:

• Children 2 months to 17 years (i.e. before their 18th birthday)
• Child will be receiving intranasal dexmedetomidine as part of their usual medical care
• Child will be undergoing a non-painful medical procedure, which includes (but is not limited to): MRI, CT scans, ABR/BAER, echocardiograms, and EEGs.

Exclusion Criteria:

• Known allergy to dexmedetomidine
• Known abnormal renal or hepatic function
• Known cardiac conduction abnormality or heart block
• Current use of digoxin or beta-blockers

Children undergoing sedation using intranasal dexmedetomidine for non-painful procedures.

There is no plan to make individual participant data available to other researchers.