目的:探讨早期清醒俯卧位在轻中度急性呼吸窘迫综合征(ARDS)患者中的应用效果。并分析影响俯卧位结局的相关因素。
方法:进行前瞻性队列研究。本研究以2020年1月至2023年6月在英上县人民医院急诊科收治的轻中度ARDS患者为研究对象。根据易位公差试验的结果,将患者分为清醒俯卧位组和非俯卧位组。所有患者均按照标准程序给予高流量鼻插管(HFNC)。清醒俯卧位组患者在入院后12小时内接受俯卧位治疗,除了标准治疗。这可以执行几次,至少一天一次,每次至少2小时。为了尽可能延长俯卧位,患者被允许移动或保持小角度侧俯卧。入院后0、24、48和72小时氧合指数(PaO2/FiO2)的变化,重症监护病房(ICU)转院率,无创通气(NIV)的使用率和使用时间,总住院时间,记录俯卧位患者的每日俯卧位时间和2小时ROX指数[脉搏氧饱和度/吸入氧分数(SpO2/FiO2)和呼吸频率(RR)之比]。HFNC的成功终止被定义为成功的俯卧位,俯卧位失败被定义为转换为NIV或转移到ICU。进行亚组分析,采用二元多因素Logistic回归分析筛选早期清醒俯卧位结局的影响因素。
结果:最终共纳入107例患者,清醒俯卧位组61人,非俯卧位组46人。随着入院时间的延长,两组PaO2/FiO2逐渐增加。清醒俯卧位组入院后24小时PaO2/FiO2明显高于0小时[mmHg(1mmHg≈0.133kPa):191.94±17.86vs.179.24±29.27,P<0.05],而非俯卧位组的差异仅在72小时时具有统计学意义(mmHg:198.24±17.99vs.181.24±16.62,P<0.05)。此外,清醒俯卧位组入院后48小时和72小时的PaO2/FiO2显著高于非俯卧位组.清醒俯卧位组NIV使用率明显低于非俯卧位组[36.1%(22/61)vs.56.5%(26/46),P<0.05];Kaplan-Meier曲线分析进一步证实,清醒俯卧位组患者使用NIV后,NIV累积使用率明显低于非俯卧位组(Log-Rank检验:χ2=5.402,P=0.020)。与非俯卧位组相比,清醒俯卧位组ICU转移率显著降低[11.5%(7/61)vs.28.3%(13/46),P<0.05],和HFNC时间,NIV时间,总住院时间明显缩短[HFNC时间(天):5.71±1.45vs.7.24±3.36,NIV时间(天):3.27±1.28vs.4.40±1.47,总住院时间(天):11(7,13)vs.14(10,19),均P<0.05]。在61例进行清醒俯卧位的患者中,39成功了22失败与成功组相比,失败组患者的体重指数[BMI(kg/m2):26.61±4.70vs.22.91±5.50,P<0.05],较低的PaO2/FiO2,无症状低氧血症的比例和俯卧位的2小时ROX指数[PaO2/FiO2(mmHg):163.73±24.73vs.185.69±28.87,无症状低氧血症比例:18.2%(4/22)vs.46.2%(18/39),俯卧位2小时ROX指数:5.75±1.18vs.7.21±1.45,均P<0.05],和较短的每日俯卧定位时间(小时:5.87±2.85vs.8.05±1.99,P<0.05)。二元多因素Logistic回归分析显示,上述因素均为清醒倾向定位结局的影响因素(均P<0.05)。其中BMI[比值比(OR)=1.447,95%置信区间(95CI)为1.105-2.063]和非无症状性低氧血症(OR=13.274,95CI为1.548-117.390)是俯卧位失败的危险因素,而PaO2/FiO2(OR=0.831,95CI为0.770-0.907),每日俯卧位定位时间(OR=0.482,95CI为0.236-0.924),俯卧位2小时ROX指数(OR=0.381,95CI为0.169~0.861)为保护因素。
结论:在HFNC支持下,轻度至中度ARDS患者的早期清醒倾向定位是安全可行的,减少NIV的使用率和持续时间,降低ICU转移率,缩短住院时间。高BMI和无症状低氧血症是俯卧位失败的危险因素,而俯卧位2小时内PaO2/FiO2和ROX指数较高(患者对俯卧位反应良好),延长每日俯卧位可以提高俯卧位的成功率。
OBJECTIVE: To investigate the application effect of early awake prone position in mild-to-moderate acute respiratory distress syndrome (ARDS) patients, and analyze the related factors affecting the prone position outcome.
METHODS: A prospective cohort study was conducted. The mild-to-moderate ARDS patients admitted to the emergency department of Yingshang County People\'s Hospital from January 2020 to June 2023 were enrolled as the research subjects. According to the results of prone tolerance test, the patients were divided into awake prone position group and non-prone position group. All patients were given high flow nasal cannula (HFNC) according to the standard procedures. The patients in the awake prone position group received prone position treatment within 12 hours after admission, in addition to the standard treatment. This could be performed in several times, at least once a day, and at least 2 hours each time. In order to prolong the prone position as much as possible, the patients were allowed to move or keep a small angle side prone. The changes of oxygenation index (PaO2/FiO2) at 0, 24, 48, and 72 hours after admission, the rate of intensive care unit (ICU) transfer, the use rate and use time of non-invasive ventilation (NIV), the total hospital stay, and the daily prone position time and 2-hour ROX index [ratio of pulse oxygen saturation/fraction of inspired oxygen (SpO2/FiO2) and respiratory rate (RR)] of prone position patients were recorded. The successful termination of HFNC was defined as the successful prone position, and the failure of prone position was defined as switching to NIV or transferring to ICU. Subgroup analysis was performed, and the binary multivariate Logistic regression analysis was used to screen the influencing factors of the early awake prone position outcome.
RESULTS: A total of 107 patients were finally enrolled, with 61 in the awake prone position group and 46 in the non-prone position group. Both groups showed a gradual increase in PaO2/FiO2 with prolonged admission time. The PaO2/FiO2 at 24 hours after admission in the awake prone position group was significantly higher than that at 0 hour [mmHg (1 mmHg ≈ 0.133 kPa): 191.94±17.86 vs. 179.24±29.27, P < 0.05], while the difference in the non-prone position group was only statistically significant at 72 hours (mmHg: 198.24±17.99 vs. 181.24±16.62, P < 0.05). Furthermore, the PaO2/FiO2 at 48 hours and 72 hours after admission in the awake prone position group was significantly higher than that in the non-prone position group. The use rate of NIV in the awake prone position group was significantly lower than that in the non-prone position group [36.1% (22/61) vs. 56.5% (26/46), P < 0.05]; Kaplan-Meier curve analysis further confirmed that the patients in the awake prone position group used NIV later, and the cumulative rate of NIV usage was significantly lower than that in the non-prone position group (Log-Rank test: χ 2 = 5.402, P = 0.020). Compared with the non-prone position group, the ICU transfer rate in the awake prone position group was significantly lowered [11.5% (7/61) vs. 28.3% (13/46), P < 0.05], and the HFNC time, NIV time, and total hospital stay were significantly shortened [HFNC time (days): 5.71±1.45 vs. 7.24±3.36, NIV time (days): 3.27±1.28 vs. 4.40±1.47, total hospital stay (days): 11 (7, 13) vs. 14 (10, 19), all P < 0.05]. Of the 61 patients who underwent awake prone positioning, 39 were successful, and 22 failed. Compared with the successful group, the patients in the failure group had a higher body mass index [BMI (kg/m2): 26.61±4.70 vs. 22.91±5.50, P < 0.05], lower PaO2/FiO2, proportion of asymptomatic hypoxemia and 2-hour ROX index of prone position [PaO2/FiO2 (mmHg): 163.73±24.73 vs. 185.69±28.87, asymptomatic hypoxemia proportion: 18.2% (4/22) vs. 46.2% (18/39), 2-hour ROX index of prone position: 5.75±1.18 vs. 7.21±1.45, all P < 0.05], and shorter daily prone positioning time (hours: 5.87±2.85 vs. 8.05±1.99, P < 0.05). Binary multivariate Logistic regression analysis showed that all these factors were influencing factors for the outcome of awake prone positioning (all P < 0.05), among which BMI [odds ratio (OR) = 1.447, 95% confidence interval (95%CI) was 1.105-2.063] and non-asymptomatic hypoxemia (OR = 13.274, 95%CI was 1.548-117.390) were risk factors for failure of prone position, while PaO2/FiO2 (OR = 0.831, 95%CI was 0.770-0.907), daily prone positioning time (OR = 0.482, 95%CI was 0.236-0.924), and 2-hour ROX index of prone position (OR = 0.381, 95%CI was 0.169-0.861) were protective factors.
CONCLUSIONS: Early awake prone positioning in patients with mild-to-moderate ARDS supported by HFNC is safe and feasible, reducing the use rate and duration of NIV, lowering the ICU transfer rate, and shortening the hospital stay. High BMI and non-asymptomatic hypoxemia are risk factors for failed prone position, while higher PaO2/FiO2 and the ROX index within 2 hours of prone position (the patient\'s good response to prone position), and prolonged daily prone position can improve the success rate of prone position.