A Comparison of Oral Chloral Hydrate and Sublingual Midazolam Sedation for Echocardiogram in Children
Thanarat Layangool MD*, Chaisit Sangtawesin MD*, Thawatchai Kirawittaya MD*, Worakan Prompan MD*, Anchalee Attachoo MD**, Amornrat Pechdamrongsakul RN*, Yanisa Intasorn RN*, Prisana Hanchai RN*, Chalerat Ounjareon RN*, Putra Noisang RN*
Affiliation : * Cardiology Unit, Queen Sirikit National Institute of Child Health, Department of Medical services, College of Medicine, Rangsit University, Bangkok ** Anesthetic Unit, Queen Sirikit National Institute of Child Health, Bangkok
Objective : To compare the efficacy and safety of oral chloral hydrate and sublingual midazolam to sedate the
children undergoing echocardiography.
Material and Method: A double-blind, randomized trial study in the children judged to require sedation prior
echocardiogram were performed. Two hundred sixty-four patients between 6 months and 5 years of age were
randomized to chloral hydrate or midazolam groups. Either 50 mg/kg of chloral hydrate orally or 0.3 mg/ kg
of midazolam sublingually was given in each groups. If the child was not responded within 30 minutes after the
first dose, another half dose of each drug for the second dose will be required. The action duration time,
sedation score level and the ability to complete echocardiogram were collected.
Results : Both groups were comparable with respect to age, sex, body weight, underlying heart disease,
baseline O2 saturation and functional heart classification. The children in chloral hydrate group needed the
second dose for sedation more than midazolam group (10.6%, 5.3% p = 0.111). The onset, action duration and
total study time were significantly shorter in midazolam than in chloral hydrate group (p < 0.001). The
number of the patients who had the action duration within the optimal time (< 45 min) were significantly more
cases in midazolam than in chloral hydrate group (93.1%, 43.5% p < 0.001). Success rate of echocardiogram
was 99.2% in each group. There was no difference in echocardiographic time performed in both groups. The
children in chloral hydrate group had deeper in level of sedation (p < 0.001). Both groups showed no
significant difference in term of the ability to complete echocardiographic examination. The reaction of the
children to take the medication and the number of the patients who had systemic O2 saturation change more
than 5% from the baseline were higher in chloral hydrate group significantly (14.4%, 4.5% p = 0.006 and
9.9%, 3.1% p = 0.025).
Conclusion : Sublingual midazolam at the dose of 0.3 mg/kg can be used to sedate the children at age group
between 6 months to 5 years who undergoing echocardiogram with comparable rate of success and safety as
50mg/kg of chloral hydrate orally. The less depth in the level of consciousness after sedation with midazolam
compare to chloral hydrate may be advantage in a high risk patient to avoid deep sedation but may be
disadvantage in case who need more comprehensive echocardiographic evaluation.
Keywords : Conscious sedation, Echocardiogram, Midazolam, Chloral hydrate, Heart disease, Congenital
