Managing general anesthesia for low invasive dental procedures while maintaining spontaneous respiration with low concentration remifentanil: a cross-sectional study

Background: We assessed the relationship between patient age and remifentanil dosing rate in patients managed under general anesthesia with spontaneous breathing using low-dose remifentanil in sevoflurane.Methods: The participants were patients with an American Society of Anesthesiologists Physical Status of 1 or 2 maintained under general anesthesia with low-dose remifentanil in 1.5-2.0%sevoflurane.The infusion rate of remifentanil was adjusted so that the spontaneous respiratory rate was half the rate prior to the induction of anesthesia, and H (g/kg/min) was defined as the infusion rate of remifentanil under stable conditions where the respiratory rate was half the rate prior to the induction of anesthesia for 15 minutes.The relationship between H and patient age was analyzed statistically by Spearman's correlation analysis.Results: During dental treatment under general anesthesia using low-dose remifentanil in sevoflurane, a significant correlation was detected between H and patient age.The regression line of y = -0.00079x + 0.066 (y-axis; H , x-axis; patient's age) was provided.The values of H provide 0.064 g/kg/min at 2 years and 0.0186 g/kg/min at 60 years.Therefore, as age increases, the dosing rate exhibits a declining trend.Furthermore, in the dosing rate of remifentanil when the patient's respiratory rate was reduced by half from the preanesthetic respiratory rate, the dosing rate provided was around 0.88 mL/h in all ages if the remifentanil was diluted as 0.1 mg/mL.EtCO 2 showed 51.0 5.7 mmHg, and SpO 2 was controlled within the normal range by this method.In addition, all dental treatments were performed without major problems, such as awakening and body movement during general anesthesia, and the post-anesthetic recovery process was stable.Conclusion: General anesthesia with spontaneous breathing provides various advantages, and the present method is appropriate for minimally invasive procedures.