Liu Jing, Wang Qi, Chen Yan-hua, Qin Gui-lian, Zhao Jin-hui, Zhu Li-chun
Department of Neonatology, Beijing Obstetrics and Gynecology Hospital Affiliated to Capital University of Medical Sciences, Beijing 100026, China.
Zhonghua Er Ke Za Zhi. 2005 Dec;43(12):908-10.
Infants less than 35 weeks of gestational age are susceptible to peri-/intraventricular hemorrhage (PIVH). This may be due in part to low concentrations of vitamin K-dependent coagulation factors. This study was conducted to determine the umbilical cord blood activities of vitamin K-dependent coagulation factors II, VII, IX and X in premature infants to understand whether preterm infants have absence status of these factors the changes of theses factors' activities in premature infants' umbilical blood after vitamin K(1) was given to mothers antenatally and the preventing effectiveness of PIVH after maternal antenatal supplement of vitamin K(1).
Pregnant women in preterm labor at less than 35 weeks of gestational age were randomly selected to receive antenatal vitamin K(1) intramuscular or intravenous injections 10 mg per day for 2 to 7 days (vitamin K(1) group), or no vitamin K(1) treatment (control group). Dexamethone was antenatally given to both groups of pregnant women routinely. Vitamin K(1) group had 44 infants and the control group had 133 infants. During the same period, thirty full-term neonates' cord blood samples were obtained to determine theses factors to compare with those from the premature infants. The cranial ultrasound was performed by a same physician to understand whether the neonates were complicated with PIVH and its severity.
The levels of vitamin K-dependent coagulation factors in umbilical blood in control group were significantly lower than those in full-term infants' cord blood (P < 0.05). However, in vitamin K(1) group, supplement of vitamin K(1) antenatally could significantly increase activities of factors II, VII and X in preterm infants' cord blood (P < 0.05). The total occurrence rates of PIVH in vitamin K(1) group and control group were 31.8% and 52.6%, respectively, (P = 0.017), and the frequency of severe PIVH in vitamin K(1) group and control group was 2.3% and 12.0%, respectively (P = 0.057).
Preterm infants have absence status of vitamin K-dependent coagulation factors. Administration of vitamin K(1) to pregnant women at less than 35 weeks of gestational age resulted in significantly improved activities of vitamin K-dependent coagulation factors II, VII, and X, and a significantly decreased frequency of PIVH and less severe hemorrhage in preterm infants.
孕龄小于35周的婴儿易发生脑室周围/脑室内出血（PIVH）。这可能部分归因于维生素K依赖凝血因子浓度较低。本研究旨在测定早产儿脐带血中维生素K依赖凝血因子II、VII、IX和X的活性，以了解早产儿是否存在这些因子缺乏状态，母亲产前给予维生素K（1）后早产儿脐血中这些因子活性的变化，以及母亲产前补充维生素K（1）对预防PIVH的效果。
随机选取孕龄小于35周的早产孕妇，接受每天10mg维生素K（1）肌内或静脉注射，共2至7天（维生素K（1）组），或不进行维生素K（1）治疗（对照组）。两组孕妇均常规产前给予地塞米松。维生素K（1）组有44例婴儿，对照组有133例婴儿。同期获取30例足月新生儿的脐血样本以测定这些因子，与早产儿的样本进行比较。由同一名医生进行头颅超声检查，以了解新生儿是否并发PIVH及其严重程度。
对照组脐血中维生素K依赖凝血因子水平显著低于足月婴儿脐血（P<0.05）。然而，在维生素K（1）组，产前补充维生素K（1）可显著提高早产儿脐血中因子II、VII和X的活性（P<0.05）。维生素K（1）组和对照组PIVH的总发生率分别为31.8%和52.6%，（P = 0.017），维生素K（1）组和对照组重度PIVH的发生率分别为2.3%和12.0%（P = 0.057）。
早产儿存在维生素K依赖凝血因子缺乏状态。对孕龄小于35周的孕妇给予维生素K（1）可显著提高维生素K依赖凝血因子II、VII和X的活性，显著降低早产儿PIVH的发生率及出血严重程度。
