Abstract :
Keywords Oxidative stress; Carboxyhaemoglobin; Bronchopulmonary dysplasia; Intraventricular haemorrhage Highlights * Carboxyhaemoglobin (COHb) levels may reflect the level of early oxidative stress. * Analysis of routinely performed COHb via blood gas samples of preterm infants. * Infants who developed BPD (n = 76) had higher COHb levels in the first seven days. * Higher COHb levels were also observed in infants with grade three/four IVH. Abstract Background Carboxyhaemoglobin (COHb) levels may reflect the level of early oxidative stress which plays a role in mediating free-radical-related diseases in prematurely born infants. Aim To assess the relationship of COHb levels in the first seven days of after birth to the development of bronchopulmonary dysplasia (BPD) and other free-radical-related diseases. Study design Retrospective analysis of routinely performed COHb via blood gas samples of infants born at less than 30 weeks of gestation admitted to a tertiary neonatal intensive care unit was undertaken. Subjects One hundred and four infants were included with a median (range) gestational age of 27.4 (22.4--29.9) weeks and a birthweight of 865 (395--1710) grams. Outcomes The maximum COHb per infant per day was recorded for the first 28 days and BPD and other free-radical-related diseases including intraventricular haemorrhage (IVH) were noted. The severity of BPD, requirement for home oxygen on discharge and survival to discharge were also recorded. Results Infants who developed BPD (n = 76) had significantly higher COHb levels in the first seven days [1.7% (0.3--6.8)] compared to those that did not develop BPD [1.6% (0.9--3.8); p = 0.001]. Higher COHb levels in the first seven days after birth were also observed in infants with grade three/four IVH [n = 20; 1.9% (1.0--6.8)] compared to those without [1.6% (0.3--5.6); p Conclusion Higher COHb levels in prematurely born infants were associated with the development of BPD and IVH. Abbreviations BPD, Bronchopulmonary dysplasia; COHb, Carboxyhaemoglobin; IVH, intraventricular haemorrhage; NEC, Necrotising enterocolitis; PDA, Patent ductus arteriosus; ROP, Retinopathy of prematurity Author Affiliation: (a) Department of Women and Children's Health, School of Life Course Sciences, Faculty of Life Sciences and Medicine, King's College London, SE5 9RS, United Kingdom (b) Asthma UK Centre for Allergic Mechanisms in Asthma, King's College London, SE1 9RT, United Kingdom (c) National Institute for Health Research (NIHR) Biomedical Research Centre based at Guy's and St Thomas' NHS Foundation Trust and King's College London, SE1 9RT, United Kingdom (d) Neonatal Intensive Care Centre, King's College Hospital NHS Foundation trust, London SE5 9RS, United Kingdom * Corresponding author at: Neonatal Intensive Care Centre, 4th Floor Golden Jubilee Wing, King's College Hospital, Denmark Hill, London SE5 9RS, United Kingdom. Article History: Received 4 August 2021; Revised 5 September 2021; Accepted 7 December 2021 Byline: Nadja Bednarczuk (a), Emma E. Williams (a), Anne Greenough (a,b,c), Theodore Dassios [theodore.dassios@kcl.ac.uk] (a,d,*)