RESUMO
BACKGROUND: Several drugs, when used chronically in very preterm infants, are considered to be associated with the development of late-onset circulatory collapse (LCC), which can lead to neurodevelopmental impairment. Despite its clinical importance, conclusive risk factors for LCC have yet to be identified. The aim of the present study was to investigate the relationship between LCC and diuretics, methylxanthines, levothyroxine, and sodium chloride. METHODS: Infants born at <28 weeks gestational age were enrolled and divided into two groups: the LCC group and the non-LCC group. Use of diuretics, methylxanthines, or levothyroxine, and the sodium intake in each infant were recorded. We then determined if these represented primary risk factors associated with the development of LCC, using multivariate analysis to exclude confounding factors. RESULTS: Thirty-seven preterm infants were eligible for this study. LCC developed in 10 infants; 27 infants did not develop the disease. Only methylxanthine was significantly associated with a decrease in the incidence of LCC (odds ratio, 0.04; P < 0.05). We also observed a significant positive correlation between sodium intake and the period from diuretic treatment to LCC onset. CONCLUSIONS: Methylxanthine use was significantly associated with LCC onset. Diuretics may have the ability to provoke LCC through sodium wasting, resulting in a negative balance of the electrolyte. The incidence of LCC could be lowered by paying particular attention to infants' sodium balance, and by aggressive methylxanthine treatment.