Background
cough, respiratory failure, muscle rigidity, chest wall rigidity
ADVERSE EFFECTS, RESPIRATORY FAILURE, LARYNGOSPASM
Opioids have evidently been one of the major drugs for anesthetic induction and maintenance. They provide intra- and post-operative analgesia and promote hemodynamic stability during surgery and airway manipulation by blocking sympathetic stimulation [Intravenous administration of a bolus of opioids during anesthesia induction frequently elicits unexpected adverse effects, including cough, muscle rigidity, laryngospasm, and resultant respiratory failure [A few studies have investigated chest wall rigidity due to remifentanil administration [This prospective, double-blind, randomized controlled trial aimed to investigate the development of remifentanil-induced chest wall rigidity in older patients (≥ 65 years) undergoing general anesthesia. We hypothesized that the administration sequence of hypnotics and remifentanil (order of administration: hypnotic-remifentanil versus remifentanil-hypnotic) during anesthesia induction potentially affects the development of remifentanil-induced chest wall rigidity. We also compared the effects of different types of hypnotics, including thiopental sodium and propofol, which are the most commonly administered intravenous anesthetics. This study also aimed to determine the predictive factors for chest wall rigidity in older patients.