Lung Ultrasound Targeted Recruitment (Lustr): a Novel Protocol to Optimize Open Lung Ventilation in Critically Ill Neonates

Purpose: The objective of this study was to investigate the effectiveness of an original Lung UltraSound Targeted Recruitment (LUSTR) protocol to improve the success of lung recruitment maneuvers (LRMs), performed as a rescue approach in critically ill neonates, as compared to the standard oxygenation-guided LRM. Methods: All the LUSTR maneuvers, performed in infants with oxygen saturation/fraction of inspired oxygen (S/F) ratio below 200, were included in this case-control study (LUSTR-group). The LUSTR-group was matched by the initial S/F ratio (which is inversely proportional to the severity of the respiratory insufficiency) and underlying respiratory disease with a control group of lung recruitments performed following the standard oxygenation-guided procedure (Ox-group). The primary outcome was the improvement of the S/F ratio (Delta S/F) throughout the LRM. Secondary outcomes included the variation of the Oxygen Saturation Index (OSI) and the rate of air-leaks. Results: Each group was constituted of fourteen LRMs. As compared to the standard approach, the LUSTR protocol was associated with a higher success of the procedure in terms of delta S/F (110±47.3 vs 64.1±54.6, p = 0.02), and delta OSI (8.2±6.8 vs 2.8±2.2, p = 0.01). These results remained significant after adjusting for confounding variables through multiple linear regressions. All the LRMs in the LUSTR group obtained the sonographic resolution of the lung derecruitment. Patient position before and during LRM was modified more frequently in the LUSTR group. The incidence of pneumothorax was lower, although not reaching statistical significance, in the LUSTR-group (0 vs 14.3%, p = 0.15). Conclusion: The LUSTR protocol may be a more effective and potentially safer option than the oxygenation-based procedure to guide open lung ventilation in neonates.