Background: Bronchoscopic examination including endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is well established for lung cancer diagnosis and staging. Sedation using fentanyl and midazolam is recommended during bronchoscopic examinations. Meanwhile, inadvertent oversedation is a clinical problem. The objective of this research was to estimate the frequency of apnea episodes by end-tidal capnography under fentanyl and midazolam sedation during bronchoscopy.
Methods: Eighty-five patients were enrolled retrospectively between August 2017 and March 2018 at Okayama Medical Center. Apnea was defined as the cessation of airflow for more than 10 seconds. We reviewed medical records, including capnographic data, by cap-ONE YG-227T (NIHON KOHDEN, Tokyo, Japan) during flexible bronchoscopy under fentanyl and midazolam sedation.
Results: Patients received 49.4±20.6 µg of fentanyl [mean ± standard deviation (SD)] and 4.35±2.0 mg of midazolam (mean ± SD). The patients included 52 males and 33 females; the median age was 71 (range, 31-88) years were enrolled. Apnea episodes were recorded (median duration 18 seconds) in 85 patients (100%). Prolonged apnea episodes with more than 30 seconds occurred in 56 patients (65.8%). Furthermore, the median time was 32 (range, 5-102) seconds whose delay between the onset of an apnea episode and decline in the SpO2 level of ≥4% from baseline.
Conclusions: End-tidal capnography, cap-ONE YG-227T was effective for detecting the occurrence of apnea in patients undergoing a bronchoscopic examination under fentanyl and midazolam sedation. Monitoring might be useful for preventing inadvertent oversedation.
Keywords: End-tidal capnography; bronchoscopic examination; fentanyl and midazolam sedation.