新生儿静脉导管血流动力学与肝功能的相关性研究

【】目的 探讨不同胎龄新生儿静脉导管血流动力学指标与肝功能的关系。方法 选择确诊为静脉导管未闭的新生儿175例作为病例组,并依据胎龄分为A组(55例,胎龄31～34周)、B组(58例,胎龄35～37周)、C组(62例,胎龄38～40周),于出生后2～3天应用彩色多普勒超声检测各组新生儿静脉导管内径、平均血流速度并计算血流量;选择确诊为静脉导管闭合的新生儿60例作为对照组(胎龄38～40周);观察各组肝功能指标[谷丙转氨酶(ALT)、谷草转氨酶(AST)、总胆汁酸(TBA)、血氨(NH3)、血清总蛋白(TP)]及凝血酶原时间(PT)的变化。结果 A组的静脉导管血流量明显大于B组及C组,B组的静脉导管血流量大于C组,三组间差异有统计学意义(P<0.01);A组的ALT、AST高于B组、C组及对照组(P<0.01),但B组、C组与对照组间比较差异无统计学意义(P>0.05);A组的TBA、NH3及PT均高于B组及C组,A组的TP低于B组及C组,三组间差异有统计学意义(P<0.01),但C组的TBA、NH3、TP、PT与对照组比较差异均无统计学意义(P>0.05)。结论 新生儿胎龄越小,未闭合的静脉导管血流量越大,其所引起的较大量门体静脉分流会对肝功能产生影响,而且静脉导管分流量越大,对新生儿肝功能影响越明显。     

Abnormal ductus venosus blood flow: a clue to umbilical cord complication.

We report a case of umbilical cord complication causing, fetal hypoxemia and acidemia. At 30 weeks of gestation, the patient was referred because of slightly increased amniotic fluid volume and a non-reactive cardiotocogram. Biometry was appropriate for gestational age. Umbilical artery and fetal aortic Doppler findings were normal, whereas diastolic blood flow velocities in the middle cerebral artery were increased and the ductus venosus showed severely abnormal flow velocity waveforms with reversal of flow during atrial contraction. Since other reasons for fetal hypoxemia could be excluded, careful examination of the umbilical cord was performed. Traction of the hypercoiled umbilical cord due to its course around the fetal neck and shoulders was suspected. Cesarean section confirmed the sonographic findings and fetal blood gases revealed fetal acidemia. This case indicates that investigation of fetal venous blood flow may also help to identify fetal jeopardy due to reasons other than increased placental vascular resistance.     

超声心动图指标预测新生儿动脉导管自然关闭的价值

目的:探讨早期超声心动图指标能否预测新生儿动脉导管自然关闭。方法:足月新生儿在出生后3天内进行初次超声心动图检查,观察动脉导管是否已经闭合,若动脉导管未闭且没有其它畸形,则进行随访观察,随访超过12月未闭合者则认为是无法自然闭合的动脉导管未闭患者。1995年1月~2005年3月本院共有45例随访12月动脉导管尚未闭合的患者(PDA组),另随机选取50例3天内动脉导管已经闭合的小儿作为对照组(CONTROL组),比较两组间的超声心动图指标。结果:PDA组的左房?蛐主动脉比值(LA/AO)、左室?蛐主动脉比值(LVIDd/AO)、动脉导管彩色血流最细处宽度及动脉导管肺动脉侧左向右分流速度明显高于对照组(P值分别为:P<0.001,P<0.01,P<0.001,P<0.001)。LA/AO<1.30,LVIDd/AO<1.82及动脉导管彩色血流最细处宽度<0.29cm时,预示动脉导管多可以自然关闭。LA/AO>1.39,LVIDd/AO>1.97及动脉导管彩色血流最细处宽度>0.33cm时,预示动脉导管多无法自然关闭,选择合适时机进一步治疗是必要的。结论:足月产新生儿的早期超声心动图指标对预测动脉导管能否自然关闭是非常有价值的。     

Two ductus venosus: a previously unreported anomaly

In early fetal life, the ductus venosus (DV) connects the umbilical vein, carrying nutrient-rich and oxygenated blood from the placenta to the inferior vena cava (IVC). We present the first ever case of a fetus with two ductus venosus. The fetus presented with a four-vessel cord and a dilated bowel at 31 weeks of gestation. Ultrasonography showed a persistent right umbilical vein. Echocardiographic investigation revealed normal cardiac anatomy with no major malformations. Two DVs with slightly different Doppler patterns were visualized anastomosing with the IVC. The baby was born uneventfully at 39 weeks of gestation with stable hemodynamics. Assuming every supernumerary umbilical vein should be connected to a DV for balanced circulation, a fetus with supernumerary umbilical veins lacking a corresponding number of DV connections is likely to be predisposed to complications such as hydrops fetalis and poor perinatal outcomes. The possibility of one or more umbilical veins lacking a DV connection warrants significant attention and regular monitoring from feto-maternal specialists, given the severity of the associated morbidity and mortality.     

胎儿静脉导管闭锁产前超声表现

目的 观察静脉导管(DV)闭锁胎儿产前超声表现。方法 回顾性分析20胎DV闭锁胎儿产前超声表现，记录妊娠结局。结果 20胎DV位置及走行均正常，其中16胎(16/20,80.00%)DV管壁呈等回声，3胎(3/20,15.00%)管壁呈条索状强回声，1胎(1/20,5.00%)DV管壁回声增强，其内为低回声，呈“双轨”征；CDFI均未见DV内存在血流信号。3胎(3/20,15.00%)合并其他结构畸形，包括2胎永存右脐静脉(其中1胎染色体异常)和1胎肺动脉交叉。19胎(19/20,95.00%)出生后证实为DV闭锁，出生后新生儿Apgar评分、体质量及随访均未见异常；1胎(1/20,5.00%)死于宫内，经尸检确定DV闭锁。结论 胎儿DV闭锁产前超声可见管壁呈等回声、条索状强回声或“双轨”征，腔内无血流信号。     

Effect of fetal gender on first-trimester ductus venosus blood flow.

OBJECTIVES: Recent reports have suggested that nuchal translucency (NT) measurements in the first trimester may be influenced by fetal gender. Since both NT and central venous blood flow are considered to be related to fetal cardiac function, we investigated gender-related differences in first-trimester ductus venosus Doppler indices. METHODS: A total of 73 male and 79 female normal fetuses at 10-14 weeks of gestation were included in the study. The pulsatility index for veins (PIV), peak velocity during ventricular systole (S-wave), time-averaged maximum velocity (TAMV) and A-wave velocity (A-wave) were recorded in each case and converted to the corresponding Z-scores. RESULTS: The mean Z-score values of PIV, S-wave and TAMV were significantly lower in male fetuses compared to female fetuses (P < 0.01 for all three indices). By contrast, A-wave velocities were not different in the two groups. The correlation between S-wave velocity and TAMV was significant in both male (P < 0.001) and female (P < 0.001) fetuses, while PIV did not appear to be related to TAMV either in males (P = 0.90) or in females (P = 0.49). A-wave velocity had a significant negative correlation with PIV in both groups. Finally, PIV was significantly correlated with S-wave velocity in female fetuses (P < 0.01) but not in males (P = 0.14). CONCLUSION: These findings suggest that early cardiovascular development may be different in male and female fetuses.     

Doppler waveforms: the relation between ductus venosus and inferior vena cava

This study was to assess whether or not there was correlation between the Doppler velocity waveform of the ductus venosus (DV) and inferior vena cava (IVC). A total of 142 healthy pregnant women were enrolled and divided into three groups according to the gestational weeks at the examination time. Group 1 was < or = 22 weeks; group 2 was between 22 and 28 weeks; and group 3 was > or = 28 weeks. Acuson 128xp was used to measure the Doppler velocity waveforms of DV and IVC by one experienced examiner. Doppler indices were used for analysis. Our results showed that, with the advance of pregnancy age, the resistance index of DV (DV-RI) and the preload index of IVC (IVC-PLI) were correlated with the gestational weeks, r = -0.247 and r = -0.540, respectively. There was a weak correlation between DV-RI and IVC-PLI, r = 0.202, p < 0.05; however, there was no significant correlation between DV-RI and IVC-PLI in group 1, group 2 or group 3. In conclusion, we report the first study on the correlation between DV-RI and IVC-PLI, which indicated the different roles of DV and IVC in fetal hemodynamics.     

Absence of the ductus venosus: report of 10 new cases and review of the literature.

OBJECTIVE: To assess the clinical significance of the absence of the ductus venosus. DESIGN: A retrospective study with a review of the literature. METHODS: The archives of our ultrasound laboratory and the English literature were searched for cases with a prenatal diagnosis of absence of the fetal ductus venosus. RESULTS: Between 1985 and 2000, 10 fetuses were diagnosed in our center as having absence of the ductus venosus. The review of the literature revealed 23 cases. Three main patterns of abnormal venous circulation were documented: (1) umbilical vein bypassing the liver and connecting directly to the right atrium (46%); (2) umbilical vein bypassing the liver and connecting to the inferior vena cava mostly through one of the iliac veins (25%); (3) umbilical vein connecting to the portal circulation without giving rise to the ductus venosus (21%). Major anomalies, including chromosomal aberrations, were found in 8/33 (24%) cases. Hydrops developed in 11/33 (33%) cases. Twenty fetuses with isolated absence of the ductus venosus were delivered, and 5 (20%) died. The portal vein was found to be absent in half of the infants examined after birth. CONCLUSIONS: Our results and the review of literature suggest that absence of the ductus venosus is associated with a high incidence of fetal anomalies and adverse outcomes, including associated malformations, chromosomal aberrations, in utero heart failure and absence of the portal vein. Heart failure and absence of the portal vein seem particularly frequent when absence of the ductus venosus is associated with a connection of the umbilical vein to either the inferior vena cava or the right atrium.     

静脉导管超声检测在产前检查中的应用价值

本文着重介绍超声检测静脉导管在产前检查中的应用价值,阐述静脉导管的组织解剖结构、静脉导管分流的机制以及静脉导管在诊断胎儿生长受限、先天性心脏病等疾病中的临床意义.     

高频超声预测早产儿动脉导管早期自然关闭的价值

目的探讨高频超声预测早产儿动脉导管早期自然关闭的价值。方法170名早产儿（孕周〈37周）,均在出生后24h内入院,高频及常规超声心动图连续观察动脉导管,首次超声心动图检查于出生后24h内完成,以后每天随访观察至第7天,若此期间发现动脉导管已经闭合,则不再继续随访检查。其中16名早产儿动脉导管出生7d内未自然关闭,为动脉导管早期未自然关闭（早期PDA）组,另从7d内自然关闭组中随机选取32名早产儿作为对照组,分别采用高频探头及常规心脏探头测量动脉导管内径、左房前后径与主动脉根部内径比值（LA／AO）。结果早产儿动脉导管于24、48、72h内自然关闭率分别约18．8％（32／170）、61．2％（104／170）、78．8％（134／170）,7d内达90．6％（154／170）,即早产儿出生后早期动脉导管自然关闭率约90．6％（154／170）。高频超声对动脉导管二维及彩色血流长度完整显示率均高于常规超声[82％（39／48）w46％（22／48）,P〈0．001,100％（48／48）w77．1％（37／48）,P〈0．01],差异有统计学意义。高频超声测得早期PDA组动脉导管的内径大于对照组[（2．08±O．4）mm vs （1．09±0．22）mm,P〈0．001],以1．55mm为临界值,预测早生儿出生后7d内动脉导管自然关闭的敏感度、特异度分别为87．5％、90．6％,准确性为66．5％。结论高频超声能明确诊断早产儿PDA,在精确显示动脉导管结构上优于常规超声心动图：动脉导管内径越大,早期自然关闭可能性越小。     

早孕期胎儿静脉导管频谱波型分析

目的探讨早孕期不同类型胎儿静脉导管频谱波型与胎儿生长发育及预后之间的关系。方法165例头臀长（CRL）在25-80mm之间的高危胎儿接受了经腹壁早孕期超声检查及绒毛活检。根据胎儿静脉导管血流不同波型将频谱形态分为三型：Ⅰ型：在整个心动周期内无反向血流;Ⅱ型：在心房收缩期的起始段出现很短时间内的反向血流信号,随后的大部分心房收缩期内为正向血流信号;Ⅲ型：在整个心房收缩期内为持续反向血流。所有本组胎儿进行了产前染色体核型分析、基因学及酶学检查,并随访至生后。结果在本组病例中,只有2例胎儿静脉导管频谱波型为Ⅲ型,绒毛检查结果证实其中一例为21-三体,另一例为黏多糖储积症。26例胎儿经基因学诊断为遗传性疾病,2例胎儿宫内死亡。在其余135例正常发育胎儿组中,95例（70.4%）胎儿静脉导管频谱为Ⅰ型,40例（29.6%）胎儿频谱为Ⅱ型。按胎儿头臀长分为5组（≤39mm,40-49mm,50-59mm,60-69mm,≥70mm）后,Ⅰ型/Ⅱ型胎儿例数分别为24/16、31/8、15/13、11/2、14/1。应用非参数检验的统计学方法分析,结果显示Ⅰ型及Ⅱ型频谱波型的出现频率与胎儿头臀长分组密切相关（P=0.015）,绝大多数的Ⅱ型静脉导管频谱出现在头臀长小于60mm的胎儿组中。结论通过本组正常胎儿的研究显示,早孕期胎儿静脉导管频谱波型中心房收缩早期出现的很短的反向血流信号应被视为一种“正常变异”现象,而非一种异常的静脉导管频谱类型,特别是在胎儿头臀长小于60mm时。     

Longitudinal reference ranges for ductus venosus flow velocities and waveform indices.

OBJECTIVES: Serial Doppler measurements of the ductus venosus are used increasingly for monitoring fetuses at risk of hemodynamic compromise, but existing reference ranges are based on cross-sectional studies and thus are less suitable for comparison with serial measurements. We aimed to establish longitudinal reference ranges for ductus venosus flow velocities and waveform indices and to provide the necessary terms for calculating conditional reference ranges for serial measurements. METHODS: This was a longitudinal study of 160 low-risk pregnancies. Pulsed Doppler ultrasound was used to record ductus venosus blood flow velocities at 4-week intervals from 20-22 weeks of gestation onwards. RESULTS: With a success rate of 93%, 547 measurements (four or five in each fetus) were used to establish reference ranges. The time-averaged maximum velocity was 50 cm/s at 21 weeks of gestation, increased to 60 cm/s at 32 weeks, and remained so until term. Similarly, the peak systolic velocity increased from 59 cm/s at 21 weeks to 71 cm/s at 31 weeks and remained so until term. The end-diastolic velocity showed a continuous increase from 31 cm/s at 21 weeks to 43 cm/s at 40 weeks. The pulsatility index for veins decreased from 0.57 at 21 weeks to 0.44 at 40 weeks. When conditioned by a previous measurement, the reference ranges for the next observation became narrower and commonly shifted compared with those of the entire population. CONCLUSION: The new longitudinal reference ranges presented here reflect the development of the ductus venosus flow velocities and velocity indices and are thus appropriate for serial measurements, particularly if conditional terms are included.