RESUMEN
Objective:To evaluate the efficacy of high-flow nasal cannula (HFNC) oxygen therapy in optimizing painless transesophageal echocardiography in elderly patients.Methods:Sixty American Society of Anesthesiologists Physical Status classification Ⅱ patients, regardless of gender, aged 60-75 yr, with body mass index of 18.5-23.9 kg/m 2, were randomized into 2 groups ( n=30 each) by a random number table method: group HFNC and conventional ventilation group (group C). Pure oxygen 10 L/min was inhaled for 3 min preoxygenation using the HFNC device in group HFNC. Group C inhaled pure oxygen at 6 L/min for 3 min preoxygenation via a nasal cannula. Sufentanil 0.1 μg/kg and remazolam 0.25-0.30 mg/kg were intravenously injected in turn. Group HFNC was connected to a high-flow humidification oxygen therapy device and inhaled pure oxygen at 60 L/min (37℃, FiO 2 100%). The flow rate of pure oxygen was maintained at 6 L/min (FiO 2 100 %) in group C. The patients were placed in left lateral decubitus position, esophageal ultrasound was performed after the eyelash reflex disappeared, and remazolam 0.1 mg/kg was intravenously injected intermittently when bucking and body movement were induced by operation stimulation. The occurrence of hypoxia-related adverse events, mandibular intervention and ventilation-related adverse events was observed during examination. The operation time, time of emergence from anesthesia and consumption of remazolam were recorded. Results:Compared with group C, the incidence of severe hypoxia and rate of mandibular intervention were significantly decreased (7%/0 and 53%/17%, P<0.05), the lowest intraoperative SpO 2 was increased ( P<0.05), and no significant change was found in the operation time, time of emergence from anesthesia and consumption of remazolam in group HFNC ( P>0.05). No ventilation-related adverse events occurred in both groups. Conclusions:HFNC can markedly optimize the ventilation management of elderly patients undergoing painless transesophageal echocardiography.