Comparison of the Results of Transcutaneous Carbon Dioxide and Oxygen Pressure in Premature Neonates Who Underwent Minimally Invasive Surfactant Therapy (MIST) Under Heated Respiratory Support With Nasal Cannula High Flow Air Support (HHHFNC) or Nasal Continuous Airway Pressure (CPAP) Methods

In premature babies (born before 37th week of pregnancy), surfactant production is insufficient since lung maturation has not been completed yet. Accordingly, surface tension increases in alveoli and it is difficult to keep the alveoli open, gas exchange is insufficient, and as a result, respiratory distress syndrome (RDS) occurs in premature babies. Severe respiratory failure occurs in the baby, it must be connected to the mechanical ventilator, even if hypoxia cannot be corrected, the baby may be lost. Intratracheal surfactant treatment is applied in the treatment of respiratory distress syndrome, which develops due to surfactant deficiency. With surfactant treatment, death due to RDS, mechanical ventilation requirement, morbidity due to lung disease, hospitalization times in neonatal intensive care units have been reduced and survival rates of premature babies have increased.

Intraracheal surfactant treatment is applied in RDS treatment. In recent clinical studies, two similar methods have been studied with a thin catheter without endotracheal intubation in the application of surfactant. One of these methods; Developed in Germany, it is LISA (the application of surfactant, which is less invasive), which is currently widely used in Europe. In the LISA(Less invasive surfactant administration) method, surfactant is given after placing a thin flexible catheter into the trachea with the help of a laryngoscope (Magill's forceps may or may not be used) while the baby is in CPAP. The second method is the application of surfactant, which was developed in Australia and given by using a hard thin vascular catheter into the trachea while the baby is being followed up in CPAP only under direct laryngoscope without using forceps. This method is called MIST (minimally invasive surfactant treatment). In both methods, the aim is to give the surfactant warmed up to body temperature slowly in a few minutes with the help of an injector in a baby with spontaneous breathing under CPAP.

In the current RDS review (2019), it was emphasized that noninvasive respiratory support is the most appropriate way to support the breathing of preterm infants. Non invasive methods; CPAP is specified as bi-level CPAP, HHHFNC, positive pressure ventilation with nasal interval. CPAP devices provide gas flow under controlled pressure with probes firmly placed in the nose. Through the distension pressure; Supporting the opening of the upper airway, continued lung expansion and prevention of end-expiratory alveolar collapse (lung closure at the end of breath). Thus, it is easier to release the endogenous surfactant.

Heated high flow air support (HHHFNC) moistened with nasal cannula; It has been used as an alternative to nasal CPAP since 2013 RDS guideline. The utility mechanism allows the removal of carbon dioxide in the nasopharyngeal area, provides the anatomical dead space to be washed with air flow, reduces the disadvantage of the anatomical dead space. It also provides CPAP-like support thanks to its high flow rates. It reduces breathing work. It helps to reduce the FiO2 level, typically using a flow rate of 4-8 L / min.

According to the RDS review updated in 2019, early surfactant should be applied in infants with RDS. According to the latest recommendation, surfactant should be given if the baby's FiO2 (fraction of inspired oxygen) need is over 30%.