The effects of the administration sequence and the type of hypnotics on the development of remifentanil-induced chest wall rigidity: a randomized controlled trial

Background Research on remifentanil-induced chest wall rigidity is limited. Furthermore, its incidence is unknown, and the clinical factors influencing its development remain unclear. This prospective, double-blind, randomized controlled trial aimed to investigate the effects of the administration sequence of hypnotics and remifentanil as well as the type of hypnotic administered on the development of remifentanil-induced chest wall rigidity. Methods A total of 125 older patients aged ≥ 65 years, who were scheduled to undergo elective surgery under general anesthesia, were enrolled in this study. Participants were randomly assigned to one of four groups; Thio-Remi, Pro-Remi, Remi-Thio, or Remi-Pro. After confirming the loss of consciousness and achieving a target effect-site concentration of 3 ng/mL remifentanil, the development of remifentanil-induced chest wall rigidity was evaluated. Results The incidence of chest wall rigidity was significantly higher in the remifentanil-hypnotic group than in the hypnotic-remifentanil (opposite sequence) group (55.0