Supplementary Material for: Impact of Minimally Invasive Surfactant Therapy in Preterm Infants at 29-32 Weeks Gestation P.A.Dargaville S.K.M.Ali H.D.Jackson C.Williams De Paoli A.G. 2017 <i>Background:</i> Most preterm infants born at 29-32 weeks gestation now avoid intubation in early life, and thus lack the usual conduit through which exogenous surfactant is given if needed. <i>Objective:</i> The aim of this work was to examine whether a technique of minimally invasive surfactant therapy used selectively at 29-32 weeks gestation would improve outcomes. <i>Methods:</i> We studied the impact of selective administration of surfactant (poractant alfa 100-200 mg/kg) by thin catheter in infants with respiratory distress syndrome on continuous positive airway pressure (CPAP). The threshold for consideration of treatment was CPAP ≥7 cm H2O and FiO2 ≥0.35 prior to 24 h of life. In-hospital outcomes were compared before and after introducing minimally invasive surfactant therapy (epochs 1 and 2, respectively). <i>Results:</i> During epoch 2, of 266 infants commencing CPAP, 51 (19%) reached the treatment threshold. Thirty-seven infants received surfactant via thin catheter, and CPAP failure was avoided in 34 of these (92%). For the overall cohort of infants at 29-32 weeks gestation, after the introduction of minimally invasive surfactant therapy, there were reductions in CPAP failure (epoch 1: 14%, epoch 2: 7.2%) and average days of intubation, with equivalent surfactant use and days of respiratory support (intubation + CPAP). Pneumothorax was substantially reduced (from 8.0 to 2.4%). These findings were mirrored within the subgroups reaching the severity threshold in each epoch. The incidence of bronchopulmonary dysplasia was low in both epochs. <i>Conclusions:</i> Selective use of minimally invasive surfactant therapy at 29-32 weeks gestation permits a primary CPAP strategy to be pursued with a high rate of success, and a low risk of pneumothorax.