Evaluation of the Effect of Hydroxyzine on Preoperative Anxiety and Anesthetic Adequacy in Children: Double Blind Randomized Clinical Trial

Surgical procedures can generate significant preoperative anxiety (POA) in as much as 70% of the paediatric population. The role of hydroxyzine and distractive techniques such as clowns in the management of anxiety is controversial. Our main objective was to evaluate the effect of hydroxyzine on the control of POA. The secondary objective was to assess the potential additive effect of hydroxyzine and distracting techniques. We performed a randomized double-blind, controlled clinical trial in children aged 2–16 years undergoing outpatient surgery (n = 165). Subjects were randomized to hydroxyzine (group 1) or placebo (group 2). For the secondary objective, two further groups were made by allocation by chance to hydroxyzine plus accompaniment with clowns (group 3) and placebo plus clowns (group 4). All patients were accompanied by their parents as the standard procedure. POA was determined by a modified Yale scale of POA (m-YPAS). Compliance of children during induction of anesthesia (Induction Compliance Checklist (ICC)) was also assessed. No differences (p = 0.788) were found in POA control at the time of induction measured by m-YPAS (group 1: 39.2 ± 27.9; group 2: 37.0 ± 26.1; group 3: 34.7 ± 25.5; group 4: 32.4 ± 20.5). No differences were found in the level of ICC between the different treatment arms (group 1: 1.8 ± 3.4; group 2: 1.5 ± 3.0; group 3: 1.2 ± 2.4; group 4: 1.5 ± 2.7). The combination of all treatments (group 3) was the only effective strategy to contain the progression of anxiety. In conclusion, hydroxyzine was not effective to control POA in children. The combination of hydroxyzine and clowns avoided the progression of POA in our patients. This trial is registered with ClinicalTrials.gov identifier: NCT03324828 (registered 21 September 2017, subject recruitment started on 12th January 2018).