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BACKGROUND A new software has recently been incorporated in almost all new anaesthesia machines to enable automatic lung recruitment manoeuvres. To date, no studies have assessed the safety and efficacy of these automatic software programs in the neonatal population. AIMS We aimed to evaluate the safety and efficacy of the lung recruitment manoeuvre performed using the automatic stepwise recruitment manoeuvre software of the FLOW-i 4.3 Anesthesia System® in a healthy and live neonatal model. METHODS Eight male newborn piglets were included in the study. The lung recruitment manoeuvre was performed in pressure-controlled ventilation with a constant driving pressure (15 cmH2 O) in a stepwise increasing positive end-expiratory pressure (PEEP) model. The target peak inspiratory pressure (PIP) was 30 cmH2 O and PEEP was 15 cmH2 O. The manoeuvre lasted for 39 seconds. The haemodynamic variables were monitored using the PICCO® system. The following respiratory parameters were monitored: oxygen saturation, fraction of inspired oxygen, partial pressure of oxygen and carbon dioxide in the arterial blood, end-tidal carbon dioxide pressure, PIP, plateau pressure, PEEP, static compliance (Cstat ), and dynamic compliance (Cdyn ). Safety was evaluated by assessing the accuracy of the software, need for not interrupting the manoeuvre, haemodynamic stability, and absence of adverse respiratory events with the lung recruitment manoeuvre. Efficacy was evaluated by improvement in Cstat and Cdyn after performing the lung recruitment manoeuvre. RESULTS All lung recruitment manoeuvres were safely performed as scheduled without any interruptions. No pneumothorax or other side effects were observed. Haemodynamic stability was maintained during the lung recruitment manoeuvre. We observed an improvement of 33% in Cdyn and 24% in Cstat after the manoeuvre. CONCLUSIONS The automatic stepwise recruitment manoeuvre software of the FLOW-i 4.3 Anesthesia System® is safe and efficacious in a healthy neonatal model. We did not observe any adverse respiratory or haemodynamic events during the implementation of the lung recruitment manoeuvre in the pressure-controlled ventilation mode using a stepwise increasing PEEP (30/15 cmH2 O) approach.