The Dosage of Pethidine Hydrochloride During Bronchoscopy and Associated Factors

Abstract

Background. The dose of the antitussive pethidine required during bronchoscopy varies, and the factors influencing this dose remain unclear. Methods. We retrospectively analyzed 205 patients who underwent bronchoscopy using pethidine at our institution between January 2023 and December 2023. Patient records were reviewed, and one patient was excluded because of missing nursing records. Bronchoscopy was performed orally, without intubation. Before the procedure, 8% lidocaine spray and intravenous pethidine were administered. During the procedure, 1% lidocaine was sprayed, and additional pethidine was administered under sufficient monitoring using the prepared antagonists. Results. The mean patient age was 74.0 years old, and 116 patients were male. The mean patient weight was 56.0 kg, with 35 current smokers and 26 patients ingesting beta-blockers. The mean examination time was 30.0 minutes. The mean doses administered were 48.0, 26.3, 200.0, and 2.0 mg of 8% lidocaine, pethidine, 1% lidocaine, and midazolam, respectively. Pethidine hydrochloride was added in 61.8% of the cases either immediately after bronchoscopy initiation or at intervals during the procedure. No instances of hypotension were observed during the examination. However, three cases experienced mild bradycardia. Naloxone was not used during the procedure, and the doses administered were deemed appropriate at the discretion of the physician who performed the procedure. A multiple regression analysis revealed a significant association between pethidine dose and examination time, whereas no correlation was observed with comorbidities or techniques. Pethidine hydrochloride was presumed to be added in cases with a prolonged examination time, although the factors necessitating its addition immediately after bronchoscopy initiation remain unclear. The adjusted R-squared value of the regression equation was low. Conclusion. The dose of pethidine hydrochloride administered during a bronchoscopic examination was highly variable among individuals, necessitating individualized approaches.