Comparing HHHFNC and nCPAP Ventilation Methods for the Prevention of Extubation Failure in Preterm Infants

Purpose is to show that HHHFNC method is as effective and safe as nCPAP and even more comfortable than it as non-invasive respiratory support for the prevention of extubation failure in preterm with gestational age of 26-32 weeks. Method Primary Outcome Measures: The effectiveness of HHHFNC and nCPAP techniques for the prevention of extubation failure within 7 days following the first extubation in preterms in need of mechanical ventilation within the first 7 postnatal days Secondary Outcome Measures: * the total duration of invasive and non-invasive respiratory support and the duration of free oxygen demand of patients * Premature morbidities such as PDA, NEC, ROP, IVH, BPDand sepsis * The degree of nasal trauma score and the degree of nasal mucosal injury * FiO2 levels first before extubation and 6 hours after extubation * The causes of reintubation such as apnea, acidosis, and increased need of FiO2 * The reintubation predisposing factors such as pneumothorax, atelectasis, PDA after extubation * The weight change in the first 7-day period after extubation * The two groups in terms of neurodevelopmental changes Study design Patients requiring mechanical ventilation for at least 6 hours on the first 7 postnatal days will be included in the study. When patients were Fi O2 \< 0,40, Pa CO2 \< 65 mmHg, pH\> 7.20, MAP (mean airway pressure) \<7 cm H2O, they will be extubated if statistically stable. Oxygen-air mixture of 4-6 l / min flow rate will be set in HHHFNC group, and pressure will be set to 5-8 cm H2O in NCPAP group. When flow is 2 l / min, FiO2 is\<0.30 at 24 hours and above, free oxygen will be introduced. In NCPAP group, when pressure is 5 cm H2O and FiO2 \< 0.30 at 24 hours and above, free oxygen will be introduced. Reintubation criteria is set as; * FiO2 of ≥ 0.50 in order to keep oxygen saturation measured by pulse oximetry above 90 % and higher, * Apnea requiring more than 6 alerts in a 24 -hour period in 6 consecutive hours or more than 1 apnea requiring positive pressure ventilation, * Persistent acidosis; presence of pH \< 7.20 and PCO2 \> 65 mmHg in two different blood gases drawn with an interval of at least 30 minutes or treatment-resistant metabolic acidosis, * Severe respiratory distress, * Pulmonary haemorrhage and cardiopulmonary arrest.