Clinical Features of Late-Onset Circulatory Collapse in Preterm Infants

ABSTRACT

PURPOSE: This study aimed to investigate the incidence and clinical features of late-onset circulatory collapse (LCC) in preterm infants. METHODS: Medical records of 327 preterm infants (born before 32 gestational weeks) admitted to the neonatal intensive care unit of Seoul National University Bundang Hospital between January 2014 and December 2017 were reviewed. LCC was defined as sudden onset of refractory hypotension occurring after 7 days of life without obvious causes, which responded to glucocorticoid administration. Clinical characteristics and outcomes in infants with LCC were compared with those in infants with hypotension associated with identifiable causes, which developed after 7 days of life. RESULTS: Among 327 preterm infants who enrolled in this study, 65 infants developed hypotension with oliguria after 7 days of life. Among these 65 infants, 35 (53.8%) met the criteria for LCC and 30 (46.2%) were diagnosed with hypotension associated with other identifiable causes. No statistically significant differences were observed in the baseline pre- and perinatal characteristics between infants with LCC and those with hypotension associated with other causes. Infants with hypotension associated with other causes showed a higher mortality rate than those with LCC (33.3% vs. 5.7%, P=0.004). The mean gestational age and birth weight of infants with LCC were 27+5±2+1 weeks and 963±245 g, respectively. LCC occurred at a mean postnatal age of 18 days. The median body weight at the time of diagnosis of LCC was 1,200 g. No association was observed between LCC and gestational age. CONCLUSION: Among preterm infants born before 32 gestastional weeks who developed hypotension after 7 days of life, nearly 50% were diagnosed with LCC without apparent identifiable causes. Infants with LCC showed a lower mortality rate than those with hypotension associated with other causes.