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Topical Airway Anesthesia for Awake-endoscopic Intubation Using the Spray-as-you-go Technique with High Oxygen Flow
Published on: January 13, 2017
Respiratory Support With Nasal High Flow Reduces Opioid Requirements During Endoscopic Retrograde
Tomotaka Mori1,2, Takao Ayuse3, Shuntaro Sato3
1Department of Gastroenterology and Hepatology Nagasaki University Graduate School of Biomedical Sciences Nagasaki Japan.
Objectives:
Nasal high flow (NHF) improves oxygenation, reduces the work of breathing, and stabilizes ventilation. In endoscopic retrograde cholangiopancreatography (ERCP) under dexmedetomidine-based sedation, opioids are often required but increase the risk of respiratory depression and delayed recovery. This study tested the hypothesis that NHF therapy, compared with low-flow oxygen (LFO), may reduce opioid requirements during ERCP.
Methods:
This open-label, single-center, randomized controlled trial enrolled patients undergoing ERCP under dexmedetomidine-based sedation. Patients were randomized to NHF or LFO. Sedation used dexmedetomidine, midazolam and pethidine with a standardized protocol. The primary endpoint was total pethidine dose. Secondary endpoints included transcutaneous carbon dioxide (TcCO2), oxygenation-perfusion parameters, processed electroencephalography (EEG) parameters, sedative doses, and sedation depth.
Results:
Enrollment ended early at a total of 94 of the planned 118 patients due to slow recruitment (NHF 47, LFO 47). Poisson regression demonstrated reduced opioid requirements with NHF (incidence rate ratio 0.77, 95% confidence interval, 0.62-0.96, p = 0.023). The total pethidine dose was lower in the NHF group (medians 43.75 mg vs. 70.00 mg, p = 0.004). The TcCO2 and oxygenation-perfusion parameters were comparable between groups. EEG tests showed lower patient state index and electromyographic activity in the NHF group, indicating deeper sedation. No adverse events attributable to interventions were observed.
Conclusion:
NHF reduced opioid requirements while maintaining oxygenation, ventilation, and sedation during ERCP. The ability of NHF to provide respiratory support, ensure adequate oxygenation, and allow monitoring of breathing makes it a promising modality during procedural sedation; however, further multi-center studies are needed.
Trial Registration:
072210047 [jRCTs].
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