The future of paediatric acute respiratory distress syndrome

Heterogeneity is a familiar concept to paediatric intensive care physicians, because patients, pathologies, and treatments vary both within the paediatric intensive care unit (PICU) and within a given disease process. Paediatric acute respiratory distress syndrome (ARDS) typifies this problem. Children with ARDS vary in terms of age (and therefore lung development), underlying cause (pneumonia, sepsis, or trauma), pre-existing comorbid conditions, and baseline immunological state. There is not one pathway by which ARDS occurs or manifests, as indicated by the identification of hyperinflammatory and hypoinflammatory subtypes in adults and children. 1 Calfee CS Delucchi KL Sinha P et al. Acute respiratory distress syndrome subphenotypes and differential response to simvastatin: secondary analysis of a randomised controlled trial. Lancet Respir Med. 2018; 6: 691-698 Google Scholar , 2 Dahmer MK Yang G Zhang M et al. Identification of phenotypes in paediatric patients with acute respiratory distress syndrome: a latent class analysis. Lancet Respir Med. 2022; 10: 289-297 Google Scholar Furthermore, treatments probably differ in their effectiveness, with interventions that are beneficial in some patients but harmful in others, leading to a null population average treatment effect. 3 Prescott HC Calfee CS Thompson BT Angus DC Liu VX Toward smarter lumping and smarter splitting: rethinking strategies for sepsis and acute respiratory distress syndrome clinical trial design. Am J Respir Crit Care Med. 2016; 194: 147-155 Google Scholar Thus, important questions need to be addressed to improve the management and outcomes of paediatric ARDS. In a Series paper in The Lancet Respiratory Medicine, 4 Kneyber MCJ Khemani RG Bhalla A et al. Understanding clinical and biological heterogeneity to advance precision medicine in paediatric acute respiratory distress syndrome. Lancet Respir Med. 2022; (published online Dec 22.)https://doi.org/10.1016/S2213-2600(22)00483-0 Google Scholar Martin Kneyber and colleagues—a multinational group of paediatric ARDS experts—provide a welcome summary of where we are now as a field, and what tools are available to address challenges for the next generation of paediatric ARDS trials. Two key questions need to be considered to improve the management and outcomes of paediatric ARDS. First, can we improve outcomes by identifying mechanisms or pathways to target therapeutically within specific subgroups? And second, can this be done through a nuanced approach rather than through the use of blunt, pleiotropic instruments? Understanding clinical and biological heterogeneity to advance precision medicine in paediatric acute respiratory distress syndromePaediatric acute respiratory distress syndrome (PARDS) is a heterogeneous clinical syndrome that is associated with high rates of mortality and long-term morbidity. Factors that distinguish PARDS from adult acute respiratory distress syndrome (ARDS) include changes in developmental stage and lung maturation with age, precipitating factors, and comorbidities. No specific treatment is available for PARDS and management is largely supportive, but methods to identify patients who would benefit from specific ventilation strategies or ancillary treatments, such as prone positioning, are needed. Full-Text PDF