Scheuermann S, Tan A, Govender P, Mckie M, Pack J, Martinez G, Falter F, George S, A Klein A
Department of Anaesthesia and Intensive Care, Royal Papworth Hospital, Cambridge, UK.
MRC Biostatistics Unit, University of Cambridge, Cambridge, UK.
Perioper Med (Lond). 2023 Apr 14;12(1):11. doi: 10.1186/s13741-023-00300-8.
Minimally invasive surgery is becoming more common and transfemoral transcatheter aortic valve replacement is offered to older patients with multiple comorbidities. Sternotomy is not required but patients must lie flat and still for up to 2-3 h. This procedure is increasingly being performed under conscious sedation with supplementary oxygen, but hypoxia and agitation are commonly observed.
In this randomised controlled trial, we hypothesised that high-flow nasal oxygen would provide superior oxygenation as compared with our standard practice, 2 l min oxygen by dry nasal specs. This was administered using the Optiflow THRIVE Nasal High Flow delivery system (Fisher and Paykel, Auckland, New Zealand) at a flow rate of 50 l min and FiO 0.3. The primary endpoint was the change in arterial partial pressure of oxygen (pO) during the procedure. Secondary outcomes included the incidence of oxygen desaturation, airway interventions, the number of times the patient reached for the oxygen delivery device, incidence of cerebral desaturation, peri-operative oxygen therapy duration, hospital length of stay and patient satisfaction scores.
A total of 72 patients were recruited. There was no difference in change in pO from baseline using high-flow compared with standard oxygen therapy: median [IQR] increase from 12.10 (10.05-15.22 [7.2-29.8]) to 13.69 (10.85-18.38 [8.5-32.3]) kPa vs. decrease from 15.45 (12.17-19.33 [9.2-22.8]) to 14.20 (11.80-19.40 [9.7-35.1]) kPa, respectively. The percentage change in pO2 after 30 min was also not significantly different between the two groups (p = 0.171). There was a lower incidence of oxygen desaturation in the high-flow group (p = 0.027). Patients in the high-flow group assigned a significantly higher comfort score to their treatment (p ≤ 0.001).
This study has demonstrated that high flow, compared with standard oxygen therapy, does not improve arterial oxygenation over the course of the procedure. There are suggestions that it may improve the secondary outcomes studied.
International Standard Randomised Controlled Trial Number (ISRCTN) 13,804,861. Registered on 15 April 2019. https://doi.org/10.1186/ISRCTN13804861.
微创手术越来越普遍，经股动脉经导管主动脉瓣置换术适用于患有多种合并症的老年患者。该手术无需开胸，但患者必须平躺且保持静止长达2 - 3小时。此手术越来越多地在清醒镇静并补充氧气的情况下进行，但低氧血症和躁动很常见。
在这项随机对照试验中，我们假设与我们的标准做法（通过干式鼻导管以每分钟2升的流量输氧）相比，高流量鼻导管给氧能提供更好的氧合效果。使用Optiflow THRIVE鼻高流量输送系统（费雪派克医疗保健公司，新西兰奥克兰）以50升/分钟的流速和0.3的氧浓度进行输氧。主要终点是手术过程中动脉血氧分压（pO）的变化。次要结局包括氧饱和度降低的发生率、气道干预措施、患者伸手触摸输氧设备的次数、脑氧饱和度降低的发生率、围手术期氧疗持续时间、住院时间和患者满意度评分。
共招募了72名患者。与标准氧疗相比，使用高流量氧疗时pO从基线的变化无差异：中位数[四分位间距]分别从12.10（10.05 - 15.22 [7.2 - 29.8]）kPa升高至13.69（10.85 - 18.38 [8.5 - 32.3]）kPa，而标准氧疗组则从15.45（12.17 - 19.33 [9.2 - 22.8]）kPa降至14.2（11.80 - 19.40 [9.7 - 35.1]）kPa。两组在30分钟后pO₂的百分比变化也无显著差异（p = 0.171）。高流量组氧饱和度降低的发生率较低（p = 0.027）。高流量组患者对其治疗的舒适度评分明显更高（p≤0.001）。
本研究表明，与标准氧疗相比，高流量氧疗在手术过程中并不能改善动脉氧合。有迹象表明它可能改善所研究的次要结局。
国际标准随机对照试验编号（ISRCTN）13804861。于2019年4月15日注册。https://doi.org/10.1186/ISRCTN13804861。
