Burden of hypoxia and intraventricular haemorrhage in extremely preterm infants

Isabel Hui Xuan Ng, Cristine Sortica Da Costa, Fred A. Zeiler, Flora Y. Wong, Peter Smielewski, Marek Czosnyka, Topun Austin

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7 Citations (Scopus)


Objective Thresholds of cerebral hypoxia through monitoring of near-infrared spectroscopy tissue oxygenation index (TOI) were used to investigate the relationship between intraventricular haemorrhage (IVH) and indices of hypoxia. Design Prospective observational study. Setting A single-centre neonatal intensive care unit. Patients Infants <28 weeks' gestation with an umbilical artery catheter. Methods Thresholds of hypoxia were determined from mean values of TOI using sequential Χ 2 tests and used alongside thresholds from existing literature to calculate percentage of time in hypoxia and burden of hypoxia below each threshold. These indices were then compared between IVH groups. Results 44 infants were studied for a median of 18.5 (range 6-21) hours in the first 24 hours of life. Sequential Χ 2 analysis yielded a TOI threshold of 71% to differentiate between IVH (16 infants) and no IVH (28 infants). Percentage of time in hypoxia was significantly higher in infants with IVH than those without, using thresholds of 60%-67%. Burden of hypoxia was significantly higher in infants with IVH than without, using thresholds of 62%-80%. With the threshold of 71%, percentage of time in hypoxia was lower by 12.2% with a 95% CI of (-25.7 to 1.2) (p=0.073), and the burden of hypoxia was lower by 29.2% hour (%h) (95% CI -55.2 to -3.1)%h (p=0.012) in infants without IVH than those with IVH. Conclusions Using defined TOI thresholds, infants with IVH spent higher percentage of time in hypoxia with higher burden of cerebral hypoxia than those without, in the first 24 hours of life.

Original languageEnglish
Pages (from-to)F242-F247
Number of pages6
JournalArchives of Disease in Childhood: Fetal and Neonatal Edition
Issue number3
Publication statusPublished - 1 May 2020


  • imaging
  • monitoring
  • neonatology
  • neurodevelopment
  • neurodisability

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