探讨高频振荡通气(HFOV)及同步间隙指令通气+压力支持通气(SIMV+PSV) 2种机械通气模式，对呼吸窘迫综合征(RDS)极低出生体重早产儿呼吸支持作用及安全性。

选择2017年10月至2019年10月，在四川大学华西第二医院进行气管插管-使用肺表面活性物质(PS)-拔管(InSurE)治疗失败的50例RDS极低出生体重早产儿为研究对象。采用回顾性分析法，按照机械通气治疗方法，将其分别纳入观察组(n＝25，采用HFOV通气模式治疗)和对照组(n＝25，采用SIMV+PSV通气模式治疗)。对2组受试儿的动脉血氧分压(PaO₂) 、动脉血二氧化碳分压(PaCO₂)、氧合指数(OI)、机械通气治疗时间、不同分级RDS受试儿机械通气治疗时间、住院时间进行统计学分析。对2组受试儿颅内出血、支气管肺发育不良(BPD)、早产儿视网膜病变(ROP)、肺炎、新生儿坏死性小肠结肠炎(NEC)等RDS并发症发生率进行统计学比较。本研究遵循的程序符合2013年修订的《世界医学协会赫尔辛基宣言》要求，所有受试儿监护人签署参加本研究知情同意书。

①2组受试儿性别构成比、胎龄、出生体重、生后时间、分娩方式构成比等一般临床资料比较，差异均无统计学意义(P>0.05)。②机械通气治疗24 h后，观察组受试儿PaO₂、PaCO₂水平及OI明显高于、低于及低于对照组，分别为(90.2±13.8) mmHg (1 mmHg＝0.133 kPa)与(82.6±11.5) mmHg, (38.1±5.2) mmHg与(46.5±6.1) mmHg及10.6±2.7与17.3±3.9，并且差异均有统计学意义(t＝2.115、P＝0.040，t＝5.240、P<0.001，t＝7.484、P<0.001)。③观察组受试儿机械通气治疗时间、住院时间均短于对照组[(82.6±7.3) h vs (93.7±8.9) h，(27.5±2.5) h vs (31.5±3.0) h]，并且差异有统计学意义(t＝4.822、5.121，P<0.05)。④观察组Ⅱ、Ⅲ、Ⅳ级RDS受试儿的机械通气治疗时间，均短于对照组，并且差异亦均有统计学意义( P<0.05)。⑤观察组受试儿机械通气治疗相关并发症发生率为4.0%(1/25)，低于对照组的32.0%(8/25)，并且差异有统计学意义(χ²＝4.878, P<0.05)。

对RDS极低出生体重早产儿采取SIMV+PSV通气模式治疗，较HFOV能显著改善其临床症状，减少机械通气治疗相关并发症发生率。SIMV+PSV通气模式治疗，是该类受试儿安全、有效的治疗方式之一。

To explore the efficacy and safety of high frequency oscillatory ventilation (HFOV) and synchronized intermittent mandatory ventilation and pressure support ( SIMV+ PSV) in very low birth weight infants with respiratory distress syndrome (RDS).

Fifty very low birth weight preterm infants with RDS who failed after intubation-surfactant-extubation (InSurE) treatment at Chengdu Second People′s Hospital from October 2017 to October 2019 were enrolled. The random number table method was used to divide them into observation group (n=25, treated by HFOV ventilation mode) and control group (n=25, treated by SIMV+ PSV ventilation mode). A retrospective analysis was used to statistically analyze the following indexes between two groups: arterial partial pressure of oxygen (PaO₂), arterial partial pressure of carbon dioxide (PaCO₂), oxygenation index (OI), duration of invasive ventilator support. In addition, the incidence of RDS complications such as intracranial hemorrhage, bronchopulmonary dysplasia (BPD), retinopathy of prematurity (ROP), pneumonia and neonatal necrotizing enterocolitis (NEC) were statistically compared between 2 groups. Informed consent was obtained from guardians of each participant. The procedure followed in this study was in accordance with the World Medical Association Declaration of Helsinki revised in 2013.

① There were no significant differences between two groups in general clinical data, such as gender ratio, gestational age, birth weight, age and delivery mode (P>0.05). ②After 24 h of mechanical ventilation support, the PaCO₂ levels in observation group were significantly higher than those in control group [(90.2±13.8) mmHg vs (82.6±11.5) mmHg] (1 mmHg=0.133 kPa), PaCO₂ levels [(38.1±5.2) mmHg vs (46.5±6.1) mmHg], OI levels (10.6±2.7 vs 17.3±3.9) were significantly lower than those in control group, and the above differences were statistically significant (PaO₂: t=2.115, P=0.040; PaCO₂: t=5.240, P<0.001; OI: t=7.484, P<0.001). ③The duration of invasive ventilator support and hospital stay were shorter in observation group than those in control group [(82.6±7.3) h vs (93.7±8.9) h, (27.5±2.5) h vs (31.5±3.0) h], and the differences between two groups were statistically significant (t=4.822, 5.121; P<0.05). ④The duration of ventilator support for children with RDS grade Ⅱ, Ⅲ and Ⅳ in observation group was shorter than those in control group, respectively, and the above differences were statistically significant (P<0.05). ⑤ The complication rate of observation group was 4.0% (1/25), which was lower than 32.0% (8/25) of control group, and the difference was statistically significant (χ²=4.878, P<0.05).

Compared with SIMV+ PSV ventilation mode, HFOV can significantly improve the clinical symptoms and reduce the complication rate of very low birth weight preterm infants with RDS, which is a safe and effective ventilation mode for RDS.