探讨机械通气模式中，高频振荡通气(HFOV)治疗早产儿呼吸窘迫综合征(RDS)的时机选择，以及HFOV与常频机械通气(CMV)模式治疗成功率等。

选择2015年2月至2017年2月，于遂宁市中心医院诊断为RDS，并且需要进行机械通气治疗的104例RDS早产儿为研究对象。按照随机数字表法，将其随机分为首选CMV组(n＝51，首选机械通气模式为CMV)与首选HFOV组(n＝53，首选机械通气模式为HFOV)。首选CMV组51例患儿中，采取CMV治疗成功患儿为33例；CMV治疗失败患儿为18例，然后均转为HFOV治疗。采取统计学分析法，对2组患儿机械通气治疗前的一般临床资料进行分析；对治疗前及治疗后2、12、24、48 h时，吸入氧气分数(FiO₂)、氧合指数(OI)及动脉-肺泡氧分压比值(a/APO₂)，以及治疗、并发症、临床转归情况进行分析。在首选CMV组患儿中，对接受CMV治疗成功患儿与CMV治疗失败患儿的并发症、临床转归及CMV治疗前相关临床资料进行统计学比较，并且分析导致CMV治疗早产儿RDS失败的影响因素。本研究获得遂宁市中心医院伦理委员会批准，所采用的治疗方案告知患儿家属，并与所有患儿家属签署临床研究知情同意书。

①2组患儿出生胎龄、出生体重、出生后1 min Apgar评分、入院时年龄、性别构成比、极低出生体重儿比例、Ⅲ～Ⅳ级RDS比例、肺表面活性物质(PS)使用率、生后6 h内第1剂PS使用率、第2剂PS使用率、产前糖皮质激素促胎肺成熟治疗率分别比较，差异均无统计学意义(P>0.05)。②机械通气治疗前，2组患儿OI、a/APO₂、FiO₂分别比较，差异均无统计学意义(P>0.05)；机械通气治疗后2、12、24及48 h时，首选CMV组患儿OI、FiO₂，均显著高于首选HFOV组，a/APO₂低于首选HFOV组，2组比较，差异均有统计学意义(P<0.05)。③首选CMV组患儿的通气时间、氧疗时间、住院时间，均显著长于首选HFOV组，2组比较，差异均有统计学意义(P<0.05)。2组患儿气胸、支气管肺发育不良、颅内出血、肺出血发生率比较，差异均无统计学意义(P>0.05)。首选HFOV组患儿死亡率为9.4%(5/53)，显著低于首选CMV组的25.5%(13/51)，2组比较，差异有统计学意义(P＝0.030)。④首选CMV组患儿中，CMV治疗成功后，患儿最终因其他并发症导致的死亡率为12.1%(4/33)，显著低于CMV治疗失败患儿死亡率50.0%(9/18)，二者比较，差异有统计学意义(P＝0.006)。CMV失败成功患儿Ⅲ～Ⅳ级RDS、极低出生体重儿比例，均显著高于CMV治疗成功患儿，PS使用率显著低于CMV治疗成功患儿，二者比较，差异均有统计学意义(P<0.05)。

相对于CMV，采取HFOV作为首选机械通气模式治疗RDS早产儿，更有利于提高患儿治疗成功率，改善患儿预后。临床对RDS早产儿进行机械通气治疗前，对其胸部X射线摄片进行RDS分级、是否为极低出生体重儿、PS使用情况进行综合评估，有利于临床选择HFOV治疗早产儿RDS的最佳时机。

To explore the timing options of high frequency oscillatory ventilation (HFOV) for treating preterm infants with respiratory distress syndrome (RDS), and the successful treatment rates of HFOV and conventional mechanical ventilation (CMV).

From February 2015 to February 2017, a total of 104 preterm infants who were diagnosed as RDS in Suining Central Hospital and required mechanical ventilation were selected as research subjects. They were randomly divided into preferred CMV group (n=51, the preferred mechanical ventilation mode was CMV) and preferred HFOV group (n=53, the preferred mechanical ventilation mode was HFOV). In preferred CMV group, CMV treatment succeeded to 33 preterm infants, while failed to 18 preterm infants, and they changed to HFOV treatment after CMV treatment failed. The general clinical data before ventilation, the differences of oxygen index (OI), fraction of inspired oxygen (FiO₂), arterial and alveolar oxygen ratio (a/APO₂) before and 2, 12, 24, 48 hours after ventilation, the treatment situation, incidences of complication and clinical outcomes between two groups were analyzed by statistical methods. The complications, clinical outcomes and clinical data before CMV treatment between preterm infants by CMV treatment succeeded and preterm infants by CMV treatment failed in preferred CMV group were compared statistically. Meanwhile, the related influencing factors of CMV failure were analyzed. This research was approved by the Ethics Committee of Suining Central Hospital, and the treatment protocols were informed to all patients′ parents and all the parents signed the informed clinical research consents.

①There were no statistically significant differences between two groups in gestational age at birth, birth weight, Apgar score of 1 min after birth, admission age, gender ratio, ratios of very low birth infant and grade Ⅲ-Ⅳlesion of RDS in chest X-ray, rates of using pulmonary surfactant (PS), using the first agent PS within 6 hours after birth, using two agents of PS and antenatal glucocorticoids therapy for fetal maturation (P>0.05). ②There were no statistical differences between two groups in OI, a/APO₂ and FiO₂ before mechanical ventilation (P>0.05). While 2, 12, 24, 48 hours after mechanical ventilation, OI and FiO₂ in preferred CMV were higher and a/APO₂ were lower than those in preferred HFOV group, and all the differences were statistically significant (P<0.05). ③The mechanical ventilation duration, hospital stay and oxygen treatment duration in preferred CMV group all were longer than those in preferred HFOV group, and all the differences were statistically significant (P<0.05). There were no statistical differences between two groups in the incidences of pneumothorax, bronchopulmonary dysplasia, intracranial hemorrhage, pulmonary hemorrhage (P>0.05). The mortality of preferred HFOV group was 9.4% (5/53) which was significantly lower than that of 25.5% (13/51) in preferred CMV group, and the difference was statistically significant (P=0.030). ④In preferred CMV group, the mortality of preterm infants by CMV treatment succeeded was 12.1% (4/33) due to other complications after successful CMV treatment, which was significantly lower than the mortality of preterm infants by CMV treatment failed (50.0%, 9/18), and the difference was statistically significant (P=0.006). Ratios of grade Ⅲ-Ⅳ lesion of RDS in chest X-ray and very low birth infant of preterm infants by CMV treatment failed were significantly higher than those of preterm infants by CMV treatment succeeded, rate of using PS was significantly lower than that of preterm infants by CMV treatment succeeded, and all the differences were statistically significant (P<0.05).

Choosing HFOV as primary ventilation for treating preterm infants with RDS may improve the treatment success rate and prognosis of preterm infants with RDS than CMV. The assessment of RDS grade in chest X-ray, whether it is very low birth infant and the condition of using PS before ventilation may help the best timing choice of HFOV.