Background Chloral hydrate, used as premedication for paediatric medical imaging, is available in France under Temporary Use Authorisation. Because of its potential carcinogenicity, its use is being restricted to a single administration per patient. Following this re-evaluation and in the absence of consensus, the alternative choice in our hospital is intra-rectal administration of pentobarbital (PTB). However, the efficacy of PTB alone is considered variable. Therefore, a protocol associating PTB with hydroxyzine 2 mg/kg (H-PTB) has been set up.

Purpose This study evaluated whether H-PTB association offered a significant improvement in paediatric medical imaging premedication compared with PTB alone.

Material and methods The efficacy of both premedication protocols was measured over 13 months, divided into two successive periods. During period 1, PTB was used. During period 2, H-PTB was used. The efficacy of premedication was evaluated regarding various criteria, such as the average time to fall asleep, procedure conditions, etc. Data were obtained during each procedure, using a paper grid that was then imported onto a spreadsheet for computer based analyses.

Results 120 patients were enrolled (period 1, 43; period 2, 77). Average age was 30 months in the H-PTB group versus 27 months in the PTB group. Average weight was identical in the two group and PTB was administered at the same dosage (4.6 mg/kg).

The rate of falling asleep (96% vs 95%) and average lag time (66 vs 64 min) were identical. Absence of sleep or waking of the patient during installation was observed in 55% and 58% of patients, respectively. The rate of procedures successfully brought to an end was also equivalent in both groups. The average sleep duration was 61 min in the H-PTB group and 49 min in the PTB group.

Conclusion Contrary to our expectations, apart from the higher average sleep duration in the H-PTB group, sedation induced by H-PTB was similar to that of PTB on its own. The H-PTB association did not seem to improve paediatric imaging premedication in comparison with PTB alone. Regarding international guidelines, short half-life benzodiazepines seem to be suitable in this indication. Would benzodiazepine be an alternative to chloral hydrate?

References and/or acknowledgements Nice Guideline [CG112].

No conflict of interest