Brain magnetic resonance imaging using a customized vacuum shape-keeping immobilizer without sedation in preterm infants.

OBJECTIVE: To validate that a customized vacuum shape-keeping immobilizer (VaSKI) can be used in preterm infants without sedation. METHODS: Preterm infants who underwent brain MRI from February 2008 to March 2017 at Osaka Medical College Hospital were retrospectively assigned to the sedation group (February 2008 to September 2013, n = 64) or VaSKI group (October 2013 to November 2016, n = 64). The examination success rates and diagnosable case classification were determined by pediatricians and radiologists. We compared the time from preparation to examination completion between the groups. Furthermore, we measured the time from immobilization to sleep in the preterm infants in the VaSKI group. RESULTS: The examination success rate was 90.6% in both of the groups. The median (interquartile range) times of preparation were 24.0 (15.3) and 18.0 (13.0) min in the sedation and VaSKI groups, respectively. In the VaSKI group, the time from immobilization to sleep was within 3 min in 87.1% of the preterm infants. CONCLUSIONS: The brain MRI examination success rates and motion artifact suppression effects were equivalent between the groups, whereas the time from preparation to examination completion was much shorter in the VaSKI group. Therefore, the VaSKI was validated as an immobilizer for MRI in preterm infants without using sedation.

Antenatal exposure to Ureaplasma species exacerbates bronchopulmonary dysplasia synergistically with subsequent prolonged mechanical ventilation in preterm infants.

INTRODUCTION: The presence of microorganisms in gastric fluid in neonates at birth is postulated to reflect antenatal infection and also to be associated with the development of bronchopulmonary dysplasia (BPD). RESULTS: A logistic regression analysis, after controlling for other risk factors, indicated that Ureaplasma-positive infants were not at increased risk for moderate/severe BPD (adjusted odds ratio (OR): 2.58, 95% confidence interval (CI): 0.57-6.89, P = 0.12). However, the association between the presence of Ureaplasma species and the risk for moderate/severe BPD increased significantly in infants on mechanical ventilation (MV) ≥2 wk (adjusted OR: 4.17, 95% CI: 1.62-44.1, P = 0.009). An analysis using a lung injury marker indicated that Ureaplasma-positive infants with MV ≥2 wk, but not other infants, showed higher serum KL-6 levels in samples taken from cord blood, and that KL-6 levels increased time-dependently up to 4 wk of age. DISCUSSION: Antenatal exposure to Ureaplasma species induces lung injury prior to birth and synergistically contributes to the development of BPD in infants requiring prolonged MV (≥2 wk). METHODS: We recovered gastric fluid specimens from 122 infants with gestational age (GA) <29 wk or birth weight <1,000 g to investigate whether these microorganisms influence respiratory outcome of BPD. A PCR analysis was used to detect urease and 16S ribosomal RNA (rRNA) genes to classify neonates into Ureaplasma-positive or Ureaplasma-negative infants.