Review question

In children undergoing non-invasive neurodiagnostic procedures, is oral chloral hydrate more effective at producing adequate sedation and safer than other ways of achieving sedation?

Background

Neurodiagnostic procedures are non-invasive neurological investigations important for children with suspected neurological disorders. These investigations include brain imaging and brain electrical activity testing. For these tests to be successfully performed, the child needs to remain still for at least 30 to 45 minutes during the investigation period. Sedative agents are required for children, who are usually unable to remain still for this period of time.

Search date

We performed a search in multiple medical databases in July 2017.

Study characteristics

Thirteen studies involving a total of 2390 children fit our inclusion criteria. These studies were all performed in hospitals that provided neurodiagnostic services. Most of the studies assessed three main outcome measures: i) proportion of children who were unsuccessfully sedated for the neurodiagnostic procedure, ii) length of time taken for adequate sedation, and iii) side effects associated with the sedative agent. The quality of the included studies was mixed, ranging from very low to high. The quality of the studies was affected mainly because those closely involved in the trials, such as the doctors giving the sedation or the parents of the child, were not masked from knowing which sedative agent was given to the child, which could have affected their recording or interpretation of the results.

Key results

We summarised the evidence of effectiveness and harms of oral chloral hydrate sedation when compared with other sedative medications. We included 13 studies with a total of 2390 children (age up to 18 years old). The studies were all conducted in hospitals that performed neurodiagnostic procedures. Our review suggests that oral chloral hydrate is just as effective a sedative agent with similar sedation failure rate when compared with oral dexmedetomidine, oral hydroxyzine hydrochloride, and oral midazolam; and probably a more effective sedative agent with lower sedation failure rate when compared with oral promethazine. While most of the included studies showed that chloral hydrate was safe with no increased side effects when compared to other sedative agents, one study reported an increased risk of adverse effects when compared with oral dexmedetomidine.

Quality of the evidence

The quality of most of the evidence was poor due to methodological flaws in the included studies and the small sample size of each study. Consequently our confidence in the results of the studies is reduced.The major factor affecting the quality of the evidence was lack of precision in the result estimates, as the calculated plausible range of the effects were wide.

Conclusions

Apart from intravenous pentobarbital and music therapy, oral chloral hydrate is either just as effective or more effective a sedative agent when compared to other sedative agents for children undergoing non-invasive neurodiagnostic procedures. In view of the poor quality of the evidence, we could draw no clear conclusions on the effectiveness or safety of any paediatric sedative agent. The side effects profile of oral chloral hydrate when compared to other sedatives requires further study.