Predictors of Stress Exposure in Hospitalized Preterm Infants

Stress exposure in the neonatal intensive care unit (NICU) is associated with poor outcomes in preterm infants. However, factors predicting subsequent NICU stress exposure have not been identified.

To characterize NICU stressors experienced by preterm infants during the first 2 weeks of life and identify demographic, perinatal, and institutional variables associated with stress exposure.

A secondary analysis of data from a nonexperimental, prospective study was conducted using data from 60 very preterm infants born 28 to 31 weeks gestational age. Stress exposures during the first 2 weeks of life, operationalized as number of invasive procedures, were characterized by type and quantity for each infant using data extracted from electronic health records. Associations between number of invasive procedures and demographic, perinatal, or institutional variables were analyzed using linear regressions with robust standard errors.

Preterm infants experienced, on average, 98 (SD = 41.8) invasive procedures. Of these invasive procedures, nasal and/or oral suctioning episodes (58.1%), followed by skin-breaking procedures (32.6%), were most frequent. Differences in the number of invasive procedures were found for maternal race; infants born to Black mothers experienced fewer total invasive procedures than infants born to White mothers. The number of invasive procedures also varied across NICUs.

Preterm infant stress exposure differed by maternal race and NICU, consistent with research findings of differential treatment of diverse infants. Further research is needed to understand the reasons for these differences and to identify best practices to standardize neonatal care.