End-Tidal Carbon Monoxide (ETCOC) at Day One Predicts Unmyelinated White Matter (UNMWM) Volume at Term Equivalent Age of Very Preterm Neonates

Abstract

Background: Increased levels of ETCOc in preterm infants during the1st day of life are associated with inflammatory processes, oxidative stress and adverse neurodevelopmental outcome at 2 years of life (Krediet et al, Acta Pediatr 2006) Objective: To investigate the relation between early ETCOc levels and unmyelinated white matter volume. Design/methods: From a cohort of 156 extremely and very preterm infants in which ETCOc was determined within 24 h after birth, 30 infants had volumetric MR imaging at term equivalent age for determination of different cerebral tissue classes. Results: Median [range] of GA, BW and ETCOc, were 26.4 [25.0-29.9] wk, 972 [680-1700] g and 2.2 [0.7-5.5] ppm. Ventricular volume (VV) ranged from 3.0-to-28.9 ml and UnmWM/Total brain volume (TBV) ratio from 0.32-to-0.53. Linear Regression-analysis between VV and ETCOc and between UnmWM/TBV ratio and ETCOc showed a positive and negative correlation respectively (r=0.56, p< 0.02 and r= -0.73, p< 0.0001). Mulitple LR analysis (dependent Variable: UnmWM/TBV ratio; independent variables: ETCOc; GA; amnionitis; smoking; PIVH; and PDA) showed that only ETCOc was (inversely) related to the UnmWM/TBV ratio (Part F-test: 11.3), suggesting a relation between the height of ETCOc and loss of unmyelinated WM. Suggestion: ETCOc levels shortly after birth, may express oxidative stress and inflammation in the perinatal period, were related with damage of the vulnerable unmyelinated white matter in the preterm infant.