PT - JOURNAL ARTICLE AU - Namasivayam Ambalavanan AU - Waldemar A Carlo AU - Lisa A Wrage AU - Abhik Das AU - Matthew Laughon AU - C Michael Cotten AU - Kathleen A Kennedy AU - Abbot R Laptook AU - Seetha Shankaran AU - Michele C Walsh AU - Rosemary D Higgins AU - For the SUPPORT Study Group of the NICHD Neonatal Research Network TI - PaCO<sub>2</sub> in Surfactant, Positive Pressure, and Oxygenation Randomised Trial (SUPPORT) AID - 10.1136/archdischild-2014-306802 DP - 2015 Mar 01 TA - Archives of Disease in Childhood - Fetal and Neonatal Edition PG - F145--F149 VI - 100 IP - 2 4099 - http://fn.bmj.com/content/100/2/F145.short 4100 - http://fn.bmj.com/content/100/2/F145.full SO - Arch Dis Child Fetal Neonatal Ed2015 Mar 01; 100 AB - Objective To determine the association of arterial partial pressure of carbon dioxide PaCO2 with severe intraventricular haemorrhage (sIVH), bronchopulmonary dysplasia (BPD), and neurodevelopmental impairment (NDI) at 18–22 months in premature infants. Design Secondary exploratory data analysis of Surfactant, Positive Pressure, and Oxygenation Randomised Trial (SUPPORT). Setting Multiple referral neonatal intensive care units. Patients 1316 infants 24 0/7 to 27 6/7 weeks gestation randomised to different oxygenation (SpO2 target 85–89% vs 91–95%) and ventilation strategies. Main outcome measures Blood gases from postnatal day 0 to day14 were analysed. Five PaCO2 variables were defined: minimum (Min), maximum (Max), SD, average (time-weighted), and a four level categorical variable (hypercapnic (highest quartile of Max PaCO2), hypocapnic (lowest quartile of Min PaCO2), fluctuators (hypercapnia and hypocapnia), and normocapnic (middle two quartiles of Max and Min PaCO2)). PaCO2 variables were compared for infants with and without sIVH, BPD and NDI (±death). Multivariable logistic regression models were developed for adjusted results. Results sIVH, BPD and NDI (±death) were associated with hypercapnic infants and fluctuators. Association of Max PaCO2 and outcomes persisted after adjustment (per 10 mm Hg increase: sIVH/death: OR 1.27 (1.13 to 1.41); BPD/death: OR 1.27 (1.12 to 1.44); NDI/death: OR 1.23 (1.10 to 1.38), death: OR 1.27 (1.12 to 1.44), all p&lt;0.001). No interaction was found between PaCO2 category and SpO2 treatment group for sIVH/death, NDI/death or death. Max PaCO2 was positively correlated with maximum FiO2 (rs0.55, p&lt;0.0001) and ventilator days (rs0.61, p&lt;0.0001). Conclusions Higher PaCO2 was an independent predictor of sIVH/death, BPD/death and NDI/death. Further trials are needed to evaluate optimal PaCO2 targets for high-risk infants.