不同通气模式对呼吸窘迫综合征极低出生体重儿心功能的影响

目的 探讨呼吸窘迫综合征（RDS）极低出生体重儿在不同机械通气模式下心功能的变化.方法 选择本院新生儿重症监护病房2009年1月至2012年12月收治的RDS极低出生体重儿为研究对象.根据随机号将患儿分为高频振荡通气组（HFOV）和常频机械通气组（CMV）两组.在通气8～12 h、生命体征相对稳定后,采用彩色多普勒超声对两组患儿心脏泵血功能进行评价,包括心输出量（CO）、左室射血分数（EF）、每搏输出量（SV）、收缩期主动脉瓣峰值流速（AV）、收缩期肺动脉瓣峰值流速（PV）、舒张期二尖瓣口峰值流速（MV）和舒张期三尖瓣口峰值流速（TV）.结果 研究期间共收治极低出生体重儿合并RDS者152例,89例符合入选标准,其中47例在研究过程中被排除,两组最终完成研究的例数均为21例.HFOV组胎龄（29.8±1.6）周,出生体重（1335±98）g;CMV组胎龄（28.7±1.8）周,出生体重（1344±115）g.两组胎龄、日龄、体重、心率、经皮血氧饱和度、血压、血气分析和RDS分度等方面差异均无统计学意义（P＞0.05）.HFOV组MAP高于CMV组[（9.5±1.2）cmH2O比（7.2±0.6） cmH2O,P＜0.05];心功能方面,HFOV组PV和MV均低于CMV组[（0.53±0.15） m/s比（0.66±0.18） m/s,（0.53±0.22） m/s比（0.71±0.07） m/s,P＜0.05],两组CO、EF、SV、AV及TV差异均无统计学意义（P＞0.05）.结论 HFOV组MAP增高,可降低右室收缩功能及左室舒张功能,但对左室收缩射血功能无明显影响.

The effect of different mechanical ventilation modes on cardiac function in very low birth weight infants with RDS

Objective To investigate cardiac function alteration in different modes of mechanical ventilation among very low birth weight infants （VLBWI） with respiratory distress syndrome （RDS）.Methods VLBWI with RDS admitted to our NICU from Jan.2009 to Dec.2012 were studied.These infants were assigned into HFOV group and CMV group according to the corresponding ventilation modes using random grouping number generated by computer.After 8-12 h ventilation and the infants had stable vital signs,cardiac pump functions （including cardiac output （CO）,left ventricular ejection fraction（EF）,stroke volume（SV）,systolic peak velocity of aorta valve （AV）,systolic peak velocity of pulmonary artery valve （PV）,diastolic peak velocity of mitral valve （MV） and diastolic peak velocity of tricuspid valve （TV） were evaluated using 2-D Color Doppler Ultrasound.Results Total of 152 VLBWIs with RDS were admitted to the hospital during the study period and 89 cases met inclusion criteria.Of 89 cases,47 were excluded later and finally 42 were analyzed （21 cases in HFOV group and 21 in CMV group）.The mean gestational age（GA） and birth weight（BW） in HFOV group were （29.8 ± 1.6）w and （1335 ±98.2）g,respectively; The mean GA and BW in CMV group were （28.7 ± 1.8）w and （1344 ± 115.3）g,respectively; The mean airway pressure （MAP） in HFOV group was significant higher than that in CMV group [（9.5 ± 1.24）cm H2O vs.（7.19 ±0.59） cm H2O,P 〈0.05].There were no significant differences in GA,age,BW,heart rate,TcSO2,blood pressure,blood gas and RDS stage between the two groups （P 〉 0.05）.As for the cardiac pump function,PV and MV in HFOV group were significantly lower than CMV group [（0.530 ±0.146） m/s vs.（0.665 ±0.181） m/s and （0.530±0.216） m/s vs.（0.708 ±0.069） m/s,P〈0.05].There were no differences in CO,EF,SV,AV and TV between the two groups （P 〉 0.05）.Conclusions HFOV coud decrease right ventricular systolic function and left ventricular diastolic function due to higher MAP,but had no obvious influence on left ventricular pump function.