Risk factors and prognosis in very low birth weight infants treated for hypotension during the first postnatal week from the Korean Neonatal Network

Hypotension in the early stages of life appears in 20% of very low birth weight (VLBW) infants. The gestational age and birth weight are the risk factors highly related to the postnatal hypotension. Other risk factors slightly differ between different studies. So, we evaluated the risk factors and prognosis that are associated with infants treated with hypotension in the early stages of life, after excluding the influences of gestational age and small for gestational age (SGA). VLBW infants registered in the Korean Neonatal Network between 2013 and 2015 treated for hypotension within a week after their birth were selected as study subjects. The rest were used as a control group. Risk factors and the prevalence of severe complications, including mortality, were investigated and compared after matching for gestational age and SGA. The treatment rate for hypotension within the first postnatal week was inversely related to decreasing gestational ages and birth weights. In particular, 63.4% of preterm infants born at ≤ 24 weeks’ gestation and 66.9% of those with a birth weight < 500 g were treated for hypotension within a week of birth. Regression analysis after matching showed that 1-minute Apgar score, neonatal cardiac massage or epinephrine administration, symptomatic patent ductus arteriosus, early onset sepsis, and chorioamnionitis were significantly associated with hypotension. In the hypotension group, mortality, grade 3 or higher intraventricular hemorrhage, periventricular leukomalacia, and moderate to severe bronchopulmonary dysplasia rates were significantly higher after the matching for gestational age and SGA. Hypotension during the first postnatal week is very closely related to the prematurity and the condition of the infant shortly after birth. Regular prenatal care including careful monitoring and appropriate neonatal resuscitation are very crucial to decrease the risk of hypotension in the early stages of life.