INTRODUCTION
Approximately 80% of extremely preterm (gestational age <28 weeks) infants receive mechanical ventilation (MV) to maintain oxygenation and ventilation.1 A long cumulative duration of MV in preterm infants hospitalized in the Neonatal Intensive Care Unit (NICU) has been associated with higher rates of death and various neonatal morbidities, including bronchopulmonary dysplasia (BPD), upper airway injury, neurodevelopmental impairment, and nosocomial infections.1-5 An early extubation may reduce the risk of some of these complications.3, 4, 6However, about 25%-40% of elective extubations in preterm infants are not successful.7-11 Unsuccessful extubations lead to a substantial proportion of infants receiving multiple courses of MV before first discharge from NICUs.12 Failed extubation has been independently associated with an increased risk of mortality, BPD, death or BPD, severe intracranial hemorrhage, longer hospitalization, and longer duration of supplemental oxygen and ventilator support.7, 11, 13-15 It is not known if the higher rate of morbidities noted among infants who fail extubation, compared to infants who are successfully extubated, are just associations due to inherent differences among infants who fail or succeed extubation and failure of extubation is just a marker of immaturity and sickness; or whether failed extubation is independently associated with a setback in the respiratory status of these infants. The aim of this study was to evaluate the pre-extubation and post reintubation respiratory status of infants who failed an extubation attempt and to assess the time taken for these infants to achieve the pre-extubation respiratory status after reintubation.