VENTILATORY MANAGEMENT OF THE PRETERM NEONATE IN THE DELIVERY ROOM

Abstract

P remature infants need appropriate respiratory support and a lung-protective strategy, starting from the delivery room where, on the contrary, an inadequate respiratory approach may influence pulmonary outcome. The aim of the SLOMI trial was to evaluate the efficacy of sustained lung inflation (SLI) followed by early continuous positive airway pressure (CPAP) via T-piece infant resuscitator (Neopuff) as early respiratory management for preterm infants at risk of RDS in reducing their need for mechanical ventilation and ameliorating lung injury without inducing adverse effects compared with intermittent manual self inflating bag and mask ventilation. This study is a randomized case-control interventional follow up study that was conducted on 202 preterm neonates needing resuscitation in the delivery room with gestational age ranging from 27 to 33 weeks delivered at Gynecology and Obstetrics hospital, Ain-Shams University over a period of two years. They were randomized into two groups: Group I (SLI + early CPAP group) that included 108 preterm neonates needing resuscitation who were managed in the delivery room by sustained lung inflation (SLI) followed by early CPAP and group II (conventional group) that included 94 preterm neonates needing resuscitation who were managed in the delivery room by repeated manual inflations with a self-inflating bag and mask. Fifty one neonates of group I and 39 neonates of group II could not be followed up after delivery room management due to unavailability of NICU places in our hospital and were referred to other hospitals. Twenty two percent of those referred neonates in group I were intubated and mechanically ventilated in the transitional nursery before referral versus 38.5% in group II with no reported cases of pulmonary air leak in both groups. One hundred and twelve preterm neonates (57 in group I and 55 in group II) completed the study and were followed up till discharge from NICU. We chose the primary outcome to be intubation < 72 h of age and considered it failure, because failure of early nCPAP < 72 h of age is more probably due to severe RDS. The two groups were comparable for gestational age, sex, birth weight, multiple births, IUGR , mode of delivery and grade of RDS. They were also comparable for maternal factors. Neonates in group I had significantly higher 5 minute Apgar score compared with those in group II. On comparing the clinical outcomes in the present study, there was evidence of improved outcome in group I that was reflected by reduction in the number of patients intubated in the delivery room, as well as reduction in the number of neonates mechanically ventilated before 72 hrs of age. There was non significant difference between both studied groups as regards total duration of ventilatory support. In the subgroup of infants who received exclusive CPAP during NICU admission, the duration of CPAP was less in infants in group I than in group II. More cases of BPD occurred among survivors in group II than group I although the difference is statistically non significant. As regards the possible complications associated with SLI and early CPAP, neither an increase in pulmonary air leaks nor mortality was noted concluding the safety of this practice. The incidence of IVH, NEC and PDA did not differ between our both study groups. Upon comparing IL-1β levels both cord blood and after 2 hours, rise in IL-1β levels that doesn’t reach a significant level was noted in group I although there was highly significant rise in IL-1β level after 2 hours in group II. Comparing TNF-α levels both cord blood and after 2 hours didn't show any difference in both groups. While trying to find factors that predict MV before 72 hrs (failure), we found that these factors were those related to low gestational age, low birth weight and severity of RDS. Neonates who failed and were ventilated in the first 72 hours in group I had statistically significant lower 5 min. Apgar score compared to those succeeded. Lower pH occurred in the first blood gases in neonates who failed and were ventilated in the first 72 hrs in both studied groups than succeeded neonates although PCO2 did not differ significantly. Infants who were ventilated before 72 hrs of age showed significantly longer duration of ventilation, higher rates of mortality, pneumothorax, BPD, IVH, NEC and PDA. Upon comparing cytokine levels both baseline cord blood and after 2 hours in the success and failure groups, the mean serum IL-1β level after 2 hrs was significantly higher than mean baseline cord blood IL-1β in neonates who failed as well as those succeeded in group II with borderline significance among failed neonates in group I. However, we found no significant difference between mean plasma TNF-α levels after 2 hrs and mean baseline cord blood TNF -α in neonates who failed and who succeeded in both groups. We found positive correlation between IL1 β level after 2 hrs in group I and duration of ventilatory support with no correlation between TNF-α level after 2 hrs and duration of ventilatory support. By this we can conclude that higher IL1 β levels in the first day of life might be useful in predicting the severity of RDS, duration of ventilatory support and the possibility of BPD.