Intranasal Dexmedetomidine

Dexmedetomidine is a potent α-2 agonist with sedative and analgesic properties. Dexmedetomidine exhibits α-2:α-1 specificity that is eight times greater than clonidine.  Its’ sedative and anxiolytic properties are a result of its α-2 receptor specificity in the spinal cord and central nervous system.  Dexmedetomidine has a much shorter half life than clonidine (2-3 hours vs. 12-24 hours).  This pharmacokinetic profile can facilitate brief periods of deep sedation often needed for imaging procedures in pediatric sedation.

Use in MRI

Evidence supports the use of dexmedetomidine for sedation in mechanically ventilated adult patients.  There has been increasing interest in the clinical application of dexmedetomidine in the pediatric population.  High dose dexmedetomidine (3mcg/kg IV load over 10 minutes with an infusion of 1 mcg/kg/hour) has been used successfully for sedation of children undergoing sedation for MRI.  Using this dose, Mason et al noted bradycardia and a 20% drop in blood pressure with minimal change in respiratory parameters.

Buccal and Intranasal

Antilla et al documented the high bioavailability(73%-92%) when dexmedetomidine was given via the buccal route.  Onset occurred in 10-15 minutes with a peak effect at 90 minutes.  Yuen et al demonstrated the efficacy of intranasal dexmedetomidine when used in a dose of 2mcg/kg as a premedication.  Others have found dexmedetomidine, when used in a dose of 2 mcg/kg intranasal, to be an equivalent premedication to 0.5 mg/kg of po midazolam.

Our Experience

On the basis of this information, we have used intranasal dexmedetomidine as a premedication in a number of patients.  Since this drug has a neutral pH it is virtually painless when given intranasally. In addition, the use of the nasal MAD (mucosal atomization device) has allowed quick and even administration of the drug.

We reported the case of an uncooperative 10 year old autistic child that was scheduled for MRI under general anesthesia in which we gave a dose of dexmedetomidine (4 mcg/kg IN) as a premed to assist in further care.  Given this dose, this child calmed and fell asleep in the stretcher within 20 minutes.  Minimal change in heart rate and blood pressure were noted.  The child in fact slept through the duration of the scan without additional medication or anesthesia.  He was recovered in the PACU for an hour and was discharged.

Since then, we have used the dose of 4 mcg/kg IN for short scans (CT) with success.  We have also used this for ABR’s and repeated half the dose IN if the patient aroused during the study.  It should be noted that for intranasal administration we use the undiluted product which is 100 mcg/ml.  This allows for administration of a small volume which is dispensed quickly.

Further Study

All of this is anecdotal and should be studied further.  However, it is my belief that IN dexmedetomidine given alone or in combination with another drug such as ketamine may have broad application for sedation in children.  I suspect that this type of sedation would work well for dental procedures, EEG, EMG, PICC line placement, and imaging such as VCUG.

Joyce Phillips, MD, FAAP
Associate Professor
Department of Anesthesiology
University of New Mexico

Do you have experience with IN Dex?

For those who are already using IN Dex, please take a moment to make a brief comment below about your experience.

How do I use the MAD device?

Below is a link to a video that describes the use or the MAD.

MAD Video

Other Useful Articles

High Dose Dexmedetomidine as the Sole Sedative for Pediatric MRI

Dexmedetomidine for Pediatric Sedation for CT Imaging Studies

Intranasal Dexmedetomidine for Sedation during CT Scanning

Bioavailability of Dexmedetomidine after Extravascular Doses in Healthy Subjects

Buccal Administration of Dexmedetomidine as a Preanesthetic in Children

A Double-Blind, Crossover Assessment of the Sedative and Analgesic Effects of Intranasal Dexmedetomidine

A Comparison of Intranasal Dexmedetomidine and Oral Midazolam for Premedication in Pediatric Anesthesia

Intranasal Dexmedetomidine Premedication is Comparable with Midazolam in Burn Children Undergoing Reconstructive Surgery

3 thoughts on “Intranasal Dexmedetomidine

  1. Mick Connors

    Joyce,
    Can you comment on max dosing? do you max at one vial? and what is your upper weight limit?

    We use buccal dex for eeg’s and really try to stick to one vial and a max of 200, especially for cost purposes (have used 300 micrograms). Related to that we have found it ineffective for kids more than 50-60kg… have you found the same?

  2. Jennifer

    Dr. Phillips,

    Thank you for this interesting blog. Our institution has been using intranasal dexmedetomidine for the past 18 months for non-contrasted MRI’s and CT’s, ABR’s, EEG’s, echocardiograms, and anything that would require a still child for about an hour. It has been very beneficial for our practice.

    It gives us as providers another option besides chloral hydrate or placing an IV for medications and seems to be a little more predictable. We have noticed it takes most patients about 30 minutes to fall asleep and we get about 1 hour of deep sedation out of it. It appears from my clinical view that the family members appreciate having another option and feel they have more control as we allow them to hold and rock their child to sleep with this technique.

    Our dosing is very similar: we use 3 mcg/kg for children over 6 months and 2 mcg/kg for anyone under 6 months. In addition to the IN dexmedetomidine, we have found that if we combine it with intranasal midazolam 0.4mg/kg we achieve a deeper level of sedation, which helps us to get through a longer (45 minutes) MRI scan.

    When we reviewed our cases over a 12 month period we found that 91% of patients were able to complete their scheduled test without addition of other medications and that our combination intranasal dexmedetomidine and midazolam technique was pretty safe with the majority of patients needing no intervention whatsoever for breathing issues.

    Thank you for sharing your experience. We have not used IN Dex routinely on older children (we will typically put an IV in if you are older than 4 or 5) and really appreciate your experience. It is thought provoking and makes me consider using it in older children as well. Thanks for the interesting topic.

    Jennifer Schoonover CPNP-AC, PC
    Kosair Children’s Hospital
    Pediatric Anaesthesia Associates
    Louisville, KY

  3. Dr.Praful Zinzuwadia

    Dr.Phillips,
    Thank you for this interesting blog.I am using INDex for EEG’s up to the age of 5 year in dose of 2mcg/kg with good results.Can you suggest me alternative method to give IN other than MAD device.?It is thought provoking and makes me consider using it in higher doses.Thanks once again.

    Praful Zinzuwadia
    Free lance practising Anesthesiologist,
    SURENDRANAGAR–GUJARAT-INDIA

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