[Effect of high flow nasal catheter oxygen to prevent hypoxemia in endoscopic retrograde cholangiopancreatography surgery in aged].

Objective: To explore the effect of high-flow nasal catheter oxygen inhalation in preventing hypoxemia during endoscopic retrograde cholangiopancreatography (ERCP) surgery in elderly patients. Methods: From September 2021 to September 2022, 116 elderly patients (aged ≥ 70 years) who underwent elective ERCP in the Northern Theater General Hospital were prospectively selected, then divided into general nasal catheter oxygen inhalation group [group C, 31 males and 27 females, aged (79.8±6.4) years] and high-flow nasal catheter oxygen inhalation group [group H, 33 males and 25 females, aged (81.4±6.7) years], with 58 patients in each group. All patients were monitored for anesthesia by target-controlled infusion of propofol and remifentanil. The main outcome index was the incidence of intraoperative subclinical hypoxemia (90% ≤ SpO2 < 95%, duration >5 s), hypoxemia (75% < SpO2 < 90%, 5 s < duration ≤ 60 s) and severe hypoxemia (SpO2 < 75% or SpO2 < 90%, duration > 60 s). Secondary observation measures were SpO2 from T0 to T5 (T0, before anesthesia induction; T1, immediately after anesthesia induction; T2, endoscopic introduction; T3, duodenal papula intubation; T4, endoscopic withdrawal; T5, postoperative awakening), the arterial oxygen partial pressure (PaO2), carbon dioxide partial pressure (PaCO2) and pH at T0, 15 min after the induction and T5. Results: The incidence of intraoperative subclinical hypoxemia in group C and group H was 12.0% (7/58) and 3.4% (2/58) respectively, which showed no significant statistical difference (P=0.165) from each other. The incidence of intraoperative hypoxemia in group H was 8.6% (5/58), which was significantly lower than 31.0% (18/58) of group C (P=0.003). Neither group had intraoperative severe hypoxemia. SpO2 of group H were (98.2±0.9)%, (98.2±0.9)%, (97.8±1.7)% and (97.7±1.7)% at T1, T2, T3, T4, which were higher than (96.8±2.1)%, (96.4±3.0)%, (96.1±2.9)% and (96.4±3.4)% in group C (all P<0.05). PaO2 at 15 min after induction in group H was (240.5±46.7) mmHg (1 mmHg=0.133 kPa), which was higher than that of group C (170.6±33.4) mmHg (P<0.001). There was no statistically significant difference in pH and PaCO2 between the two groups of patients at each timepoint. Conclusion: High flow nasal catheter oxygen can effectively reduce the incidence of hypoxemia in ERCP in elderly patients.