Risk factors for intraventricular hemorrhage in very low and extremely low birth weight infants

Abstract

Objective To analyze the influencing factors for intraventricular hemorrhage in the very low birth weight infants (VLBWI) and extremely low birth weight infants(ELBWI). Methods The clinical data of all VLBWI and ELBWI in the Second Hospital of Wenzhou Medical College from Jan.1, 1999 to Dec.31, 2011 were retrospectively collected.They were divided into the intraventricular hemorrhage (IVH) group and non-IVH group, which included mild and severe IVH in IVH group, and then the differences of perinatal factors were analyzed in the different groups.The severity of IVH was graded based on Papile classification, and SPSS 16.0 statistical software was used for the data processing and analysis. Results A total of 925 cases were collected, and the incidence rate of IVH was 12.6%(117/925 cases), in which the severe IVH accounted for 58.4%(66/113 cases). Factors like maternal hypertension, maternal age≥30 years, gestational age, birth weight, male, small for gestational age, severe asphyxia, placental abnormalities(including placental abruption, placenta praevia, placenta adhesion, small placenta, aging of placenta), pneumonia, neonatal respiratory distress syndrome, pulmonary hemorrhage, invasive mechanical ventilation, using pulmonary surfactant(PS), chronic lung disease(CLD), necrotizing enterocolitis(NEC) were significantly different between 2 study groups(all P<0.05). Logistic regression analysis identified that gestational age<28 weeks(AOR 2.583; 95%CI: 1.357-4.916, P=0.004), maternal age≥30 years(AOR 1.638; 95%CI: 1.061-2.530, P=0.026), invasive mechanical ventilation(AOR 2.098; 95%CI: 1.262-3.488, P=0.004), NEC(AOR 3.064; 95%CI: 1.391-6.750, P=0.005), using PS(AOR 1.794; 95%CI: 1.057-3.045, P=0.030), pulmonary hemorrhage(AOR 3.372; 95%CI: 1.138-9.989, P=0.028), subarachnoid hemorrhage(SAH)(AOR 4.936; 95%CI: 1.717-14.184, P=0.003), periventricular leukomalacia(PVL)(AOR 3.157; 95%CI: 1.294-7.701, P=0.012), hypoxic-ischemic brain damage(HIBD)(AOR 3.777; 95%CI: 1.637-8.716, P=0.002) increased the risks of IVH.Invasive mechanical ventilation increased the risk of severe IVH(AOR 4.333; 95%CI: 1.861-10.088, P=0.001). Conclusions Among infants with birth weight<1 500 g, many prenatal, perinatal and postnatal factors are associated with incidence of IVH.Gestational age<28 weeks, maternal age≥30 years, invasive mechanical ventilation, NEC, exogenous PS, pulmonary hemorrhage, SAH, PVL and HIBD are risk factors for IVH.Cranial ultrasound plays a key role in the early recognition of IVH. Key words: Very low birth weight; Extremely low birth weight; Intraventricular hemorrhage; Risk factor