Neonatal pneumothorax from the perspective of a pediatric surgeon: classification and management protocol. Preliminary algorithm. Background and aim: Current neonatal pneumothorax classifications based on air volume escaping in pleural space have no contribution on the treatment. Therefore, our aim was to classify neonatal pneumothorax to guide treatment management based on our experiences. Material and methods: The records of all neonates admitted to our clinics from March 2017 to August 2020 were reviewed. The patients with pneumothorax were identified through neonatology department patient database search. The study included only the patients with symptomatic pneumothorax and these patients were evaluated into three groups based on the changes in peripheral oxygen saturation (SpO2) and clinical features immediately after tube thoracostomy (TT) procedure. Accordingly, neonatal pneumothorax was divided into three types: Patients with SpO2 increasing immediately after TT were included in Type I, patients whose SpO2 did not change after TT were included in Type II, and patients with SpO2 decreasing immediately after TT were included in Type III pneumothorax. Results: A total of 82 patients were included in the study. Sixty-one percent of these patients had Type I, 24% had Type II, and 15% had Type III pneumothorax. None of the neonates died in type I and II pneumothoraces while nine of twelve neonates (75%) died within the neonatal period in type III pneumothorax. Although we applied treatments such as high-frequency oscillatory ventilation, selective intubation, continuous negative aspiration, surgical treatment to our patients that were lost due to type III pneumothorax, we could not achieve success. We successfully managed our surviving type III pneumothorax patients with a simple pressure cycle ventilator, using a combination of high rates, modest peak airway pressures [18 to 22 cm H2O and no positive endexpiratory pressure (PEEP)] and an autologous blood patch. Conclusion: Classification of pneumothoraces into different types significantly contributes to patient treatment planning through a predetermined strategy, not through trial-and-error. High frequency and zero PEEP ventilation can provide significant improvement in risky cases.