多普勒血流频谱法估测肺出血新生儿肺动脉压的研究

目的　研究肺出血新生儿心脏收缩功能和肺动脉压力变化及临床影响因素。方法　用M型二维超声多普勒和脉冲多普勒方法分别测定28例肺出血新生儿和28例非肺出血新生儿(含17例正常新生儿)心脏收缩功能及主肺动脉血流速度频谱，以肺动脉血流峰速时间/右室射血时间(TPV/RVET)比值反映肺动脉压力，分析肺出血新生儿心脏收缩功能和肺动脉压力变化及临床影响因素。结果　肺出血新生儿TPV/RVET比值(0.253±0.041)明显低于正常对照组(0.329±0.058)和非肺出血组(0.301±0.022)(P＜0.01)；肺出血新生儿恢复期该比值(0.294±0.033)升高，肺出血死亡组TPV/RVET比值(0.219±0.022)和缩短分数［FS(31±5)%］明显低于存活新生儿(0.270±0.031，TPV/RVET39±7，FS)(P＜0.01)；TPV(52±12)ms明显低于存活新生儿(44±8)(P＜0.05)。早产儿肺出血组TPV明显缩短(P＜0.01)。肺出血组TPV/RVET比值与动脉血pH值高度相关(r=0.84，P＜0.01)。结论　肺出血新生儿伴有肺动脉压力升高，严重者心脏收缩功能降低，导致心力衰竭，致新生儿死亡。

Evslnation of pulmonary arterial pressures by Doppler echocardiography in infants with pulmonary hemorrhage

Objective　To determine cardiac function and pulmonary artery pressures in infants with pulmonary hemorrage. Methods　Twenty eight infants with pulmonary hemorrhage (PH) were studied with M mode, two dimensional, and Doppler echocardiographic techniques to measurement ventricular systolic functions and pulmonary blood flow velocity. Another 28 infants with out PH (contained 17 normal infants), matched for gestation and age, were as controls. The time to peak velocity (TPV) and right ventricular ejection time (RVET) were obtained. The TPV/RVET ratio was used to estimate pulmonary arterial pressers. Results　There were significant differences in mean (SD) TPV/RVET ratio between group with PH (0.253±0.041) and group in normal controls (0.329±0.058) and group without PH (0.301±0.022) (P<0.01). The TPV/RVET ratio in recovery phase (0.294±0.033) was similary high. The infants died from PH showed significantly lower leuels of TPV/RVET ratio (0.22±0.02) and FS (31±5,)% compared with survival infants(0.270±0.031, 39±7, respectively) (P<0.01, P<0.05); The TPV in premature PH group was significantly lower than that in full term. There was a significant correlation between pH and TPV/RVET ratio (r=0.84, P<0.01). This study showed the high incidence of patent ductus arteriosus in PH infants. Conclusion　These results revealed that infants with PH were companied with elevated pulmonary hypertension and reduced myocardial contractility which was fatal to pneumorrhagia infants. The ductus arteriosus was an important factor in the development of pulmonary hemorrhage of the newborn.