Surfactant Therapy Using INSURE Method (Intubation- SURfactant- Extubation) In Management of Respiratory Distress Syndrome and Risk Factors Contributing to Failure of This Method

Abstract

Background: The INSURE method (Intubation- SURfactant- Extubation) is increasingly being used to treat the respiratory distress syndrome in preterm infants and associated with declining the necessity for mechanical ventilation and reducing it is associated adverse events. Objectives: To evaluate the effectiveness of surfactant therapy using INSURE method in the management of respiratory distress syndrome and to identify the risk factors associated with its failure.Patients and methods: A retrospective descriptive cross sectional study was conducted in neonatal intensive care unit in Al- Yarmook Teaching Hospital, Baghdad, Iraq from April through October 2014. All preterm neonates (Gestational age 24- 34 weeks) with clinical signs and chest X- ray findings suggestive of respiratory distress syndrome and received surfactant by INSURE method were enrolled in this study and allocated into INSURE success and INSURE failure group depending whether they need re- intubation and mechanical ventilation or not.Results: The total number of neonates enrolled in this study was one hundred five; of whom number of males was 60 patients (57.1%) compared with 45 females (42.9%). The INSURE method was successful in 71 neonates (67.6%). The mean birth weight and gestational age in the failure group were 1135(± 296) grams and 28.47(± 2.402) weeks respectively, and were significantly lower than the success group (1426(± 327) grams and 30.5(± 1.969) weeks respectively. This study also showed that the INSURE method was successful in 36 among 42 (85.7%) neonates with gestational age > 30 weeks while succeed in 35 among 63(55.6 %) neonates with gestational age ≤ 30 weeks. The Apgar scores at 5 min where significantly lower in the failure group up in comparison with success group (the Apgar score between 4- 6 was present in 31.4% of success group where as 68.6% of failure group). Severe respiratory distress syndrome was significantly more common in the failure group (75.7%) than in the success group (24.3%).Severe radiological finding on CXR was significantly more common in the failure group than in success group (83.9% vs. 16.1%). The need for second dose of surfactant was significantly more common in failure group than in success group (81.1% vs. 18.9%). This study showed that the more prolonged CPAP (continuous positive airway pressure) treatment after surfactant administration, the more the INSURE method failed. Sepsis, recurrent apnea and pneumothorax were significantly more common in the failure group.Conclusion: INSURE method is very effective method in the management of respiratory distress syndrome. It is associated with decrease the need for mechanical ventilation and decline in the neonatal mortality rate. There is an increased risk of failure of this method among those preterm neonates with low birth weight, lower gestational age, lower Apgar score, severe respiratory distress syndrome with severe radiological findings on CXR and with prolonged CPAP treatment duration after surfactant administration. Complications during the course of treatment such as Sepsis, recurrent apnea and pneumothorax may adversely affect the INSURE method success.