The near term neonate with hypoxic respiratory failure is currently treated with a number of therapeutic interventions, few of which are of proven efficacy. In an effort to prospectively evaluate these approaches in a well defined large current cohort we reviewed the outcomes of the 121 control infants in the NINOS randomized controlled trial (NEJM, 1997;336:602) evaluating the use of inhaled nitric oxide (INO) on the risk of death or ECMO. The infants were enrolled from 1/94 to 5/96, > 34wks GA, with persistent pulmonary hypertension (PPHN), meconium aspiration, pneumonia/sepsis, respiratory distress syndrome +/- proven pulmonary hypertension with 2 OI's>25, and without lethal malformations. The protocol encouraged the use of therapies including HFV, alkalosis (pH>7.45), sedation, neuromuscular blockade and surfactant (S) following established individual unit practice prior to randomization in 17 NICUs in Canada and USA. This cohort was 63% male, 61% white, 21% 1min Apgar<3, BW 3359± 597g,GA 38.9± 2.2wks. Overall 77(63.6%) of the group died or received ECMO. GA, BW, etiology and interventions prior to randomization were among 32 potential risk factors tested. By univariate analysis S use (Odds ratio (OR)=0.16, 95% confidence intervals (CI) 0.06,0.44), outborn birth (OR=0.30, CI 0.11,0.83), and lower initial OI (p<0.003), significantly decreased risk (p<0.001) whereas c-section (OR=0.72), white race (OR=0.45), post-natal steroid use (OR=0.51), tolazoline (OR=0.80) or RDS (OR=0.45) were associated with a non-significantly decreased risk. Low Apgar (OR=1.66), hyperventilation (OR=1.37) neuromuscular blockade (OR=1.81) and primary PPHN (OR=1.66) were associated with a non-significantly increased risk. Lower initial OI (OR=1.1,p=0.002), outborn status (OR=0.23,p=0.02) and S use (OR=0.16,p=0.003) were the only significant predictors of the primary outcome using a multivariable logistic model with a backwards elimination procedure. These observations support previous reports that the OI is a significant predictor of death or the need for ECMO, and support the observations of Lotze et al (Ped Res, 1996;36:123A) that surfactant use may reduce the need for ECMO in such infants. Additional studies are required to better determine the interactions between risk factors and therapies for such infants.