Effect of Dexmedetomidine Versus Midazolam Versus a Combination of the Two as a Premedication for Children Undergoing Bilateral Myringotomy Tube Insertion

Children presenting for ear tube surgery (bilateral myringotomy and ventilating tube
insertion) often suffer from postoperative delirium in the recovery room. It has been
hypothesized this may be a result or side effect of a premedication, midazolam. Midazolam is
frequently administered to children preoperatively as a means of decreasing separation
anxiety. An alternative medication, dexmedetomidine, is sometimes used as an alternative to
midazolam and has also been effective in treating postoperative delirium. In this study the
investigators would like to see if there is in fact a measurable difference between children
receiving the standard midazolam or dexmedetomidine.

Patients would be randomized into one of three groups (versed alone, dexmedetomidine alone,
or a combination). Patients included would be those presenting for BMT surgery who are an
ASA physical status 1 or 2, not falling into any exclusion criteria.

Exclusion criteria would be patients with vital signs outside the normal limits as
documented under the research plan. Also to be excluded are those patients with known
genetic abnormalities predisposing to a derangement in hemodynamics or challenging airway.

The anesthesiologists listed as team members are the ones who are involved with this study
and would be responsible for providing a standard anesthetic (same technique with
inhalational anesthetic agents and intraoperative pain management) so no other variability
would need to be taken into consideration for assessment in the recovery room. The
investigators researchers, both anesthesiologists and observers will be blinded during the
study. The pharmacy will have a list of patients who have consented, and then will randomly
allocate them into one of the three groups. Only for analysis will the investigators (myself
as the PI and other members) know which patient received which drug or combination. Also, by
having the same team members performing assessment of each of the three parameters (1.
Pre-op sedation scale, 2. Mask acceptance score, and 3. Post operative emergence delirium
scale), there would be good reliability. A briefing session will be performed prior to the
study's commencement showing pictures to the reviewers so there can be an agreed upon
assessment. The MOASS or pre-operative sedation scale as well as the mask acceptance and
PAED scale have been utilized and validated in previous studies (10), while the mask
acceptance scale has been successfully utilized as well (11, 12, 13). The investigators goal
is to decrease variability by having only two members make observations.

DESCRIPTION IN LAYMEN TERMS. Please summarize this study in less than 10 sentences. Use
language an informed non-scientist can understand. Please complete within space below.

Following an obtained written consent, a child presenting for ear tube surgery will be
randomized into one of three groups for receiving a premedication. One group will be the
current therapy with midazolam, another group will be another drug dexmedetomidine, and the
third group will be a combination of midazolam plus dexmedetomidine. Observers in the study
(the investigators fellow and advance practice nurse) will not know which group each patient
belongs, and will then make three separate assessments: preoperative sedation, mask
acceptance, and postoperative delirium.

Mask acceptance: Induction of anesthesia, or the beginning of the process for the patient to
fall asleep and lose consciousness, involves placing a mask over there face, specifically
the nose and mouth. The mask is connected to their anesthesia machine via tubing, or a
circuit, through which their anesthetic gases flow. Some children fight the mask as it can
be seen as new and frightening. Other children, sometimes depending on how sedated they are
after receiving a premedication, do not fear the mask on their face and do not resist
induction. How well or easily this happens can be described as "mask acceptance."
Postoperative delirium can be seen in patients of any age or after any surgery and can be
better defined as a mental disturbance during the recovery from general anesthesia
consisting of hallucinations, delusions, and confusion manifested by moaning, restlessness,
involuntary physical activity, and thrashing about in bed. It has been considered a common
postanesthetic problem in children and adults since 1960.

Each patient will then have a set of numbers for each scale; following conclusion of the
study the investigators will be able see which drug each patient received and statistical
analysis can be completed. The investigators goal is to see if there is any difference in
any of the scales depending which medication was administered. The scales to be utilized
include the pre-operative sedation scale, the mask acceptance scale, and the pediatric
emergence delirium scale.

Inclusion Criteria:

- Age 6 mo-4 years

- ASA classification 1 or 2

- Vital signs, namely heart rate and blood pressure within the normal range for each
patient's age group

Exclusion Criteria:

- Known allergies to midazolam or dexmedetomidine

- Baseline vitals outside the range listed above

- Personal or family history of malignant hyperthermia

- Genetic abnormalities predisposing to altered hemodynamics or difficult airway

- ASA physical status 3 or greater

- Known cardiac abnormalities