Can Cardiothymic Thoracic Ratio be a Marker of Mortality in Preterm Neonates with Respiratory Distress Syndrome?

Abstract

Introduction: Thymic size is measured as Cardiothymic: Thoracic ratio (CT/T ratio) in chest X-ray. In a state of stress, the thymus tissue rapidly involutes, owing principally to the thymocytolytic effect of glucocorticosteroids. Different pre and postnatal factors affect thymic size in neonates. Aim: To determine the thymic size in preterm neonates with Respiratory Distress Syndrome (RDF), its relation to survival to determine which antenatal and postnatal factors influence thymic size. Materials and Methods: This prospective observational study was carried out in neonatal units of tertiary care hospital in North India from May 2018 to September 2019. Premature (0.361 has sensitivity 59.09% and specificity 68.18% for non survivor group. Logical regression analysis for probability of survival showed that as CT/T ratio increases probability of survival decreases. Mean CT/T ratio was not affected by gestational age, sex, mode of delivery, use of antenatal steroid, pre-eclampsia, mother’s parity, perinatal asphyxia and sepsis. Conclusion: The mean CT/T ratio was higher in non surviving neonates with RDS as compared to those who survived. Mean CT/T ratio is a poor predictor for mortality in premature neonates with RDS.

Keywords

• newborns
• predictor
• prematurity
• thymic tissue