CXCL8 and acute lung injury: Zhao et al. [27] developed a model based on APACHE III, age, surfactant protein D and interleukin (IL)-8 based on the cohort of the Assessment of Low tidal Volume and elevated End-expiratory volume to Obviate Lung Injury (ALVEOLI) study with external validation in the Fluid and Catheter Treatment Trial (FACTT) and Validating Acute Lung Injury biomarkers for Diagnosis (VALID) studies and found a moderate discrimination of the model; however, the use of surfactant protein D and IL-8 is not routinely practiced in intensive care units, making their application difficult in daily practice.