Zolpidem for Persistent Vegetative State – A Placebo-Controlled Trial in Pediatrics

Abstract

Objective: The aim of this study was to determine if zolpidem is associated with improved responsiveness or regional cerebral perfusion in patients with persistent vegetative states.

Methods: Following ethics approval, children with persistent vegetative state were enrolled in a prospective, double-blind, placebo-controlled randomised trial. Patients underwent 2 treatments of 4 days, separated by 10 days. Each child received either a daily dose of zolpidem or placebo with a dosage of 0.14–0.2 mg/kg. Responsiveness and regional cerebral perfusion were the outcomes of interest. These were assessed using the Rancho levels of cognitive functioning scale, the coma/near-coma scale and F¹⁸-FDG positron emission tomography. These were conducted at baseline and after completion of the treatments.

Results: 3 children were enrolled. The Rancho assessment scales showed no change with treatment. The coma/near-coma scale showed a tendency to increase with zolpidem, suggesting reduced responsiveness − when compared to baseline or placebo. The positron emission tomography scans showed no significant changes between treatments.

Conclusion: Zolpidem was associated with a tendency towards reduced responsiveness in patients with persistent vegetative states. There were no objective changes on positron emission tomography suggestive of an associated increase in cerebral blood flow with zolpidem. It would appear that zolpidem does not offer a beneficial effect in this setting.

Key words

persistent vegetative state - zolpidem - pediatrics - positron emission tomography

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