Clinical characteristics and early predictors of post-drowning acute respiratory distress syndrome in children: A retrospective cohort study in Hainan

<title>Abstract</title> <p> <bold>Background:</bold> This study characterized the clinical features of post-drowning acute respiratory distress syndrome (ARDS) in children. <bold>Methods:</bold> We retrospectively enrolled 212 drowning patients treated in the pediatric intensive care units (PICUs) of two large tertiary referral centers, namely Sanya Maternal and Child Hospital and Hainan General Hospital, Hainan Province, China, between January 2016 and December 2025. Patients were divided into ARDS and non-ARDS groups and their clinical data collected and compared. Variables showing intergroup differences were screened based on clinical experience, published evidence, least absolute shrinkage and selection operator (LASSO) regression, and variance inflation factor (VIF) assessment and subsequently subjected to multivariable analysis. <bold>Results:</bold> Children in the ARDS versus non-ARDS group had a longer drowning duration, higher proportion of seawater drownings, and greater overall disease severity manifested by irregular breathing, a prolonged capillary refill time, elevated inflammatory markers, and decompensated metabolic acidosis (all P &lt; 0.05). Patients in the ARDS group were more likely to show a white-out appearance on chest radiography and develop concomitant infections. Moreover, they were more likely to have multiple organ dysfunction syndrome (MODS), require invasive mechanical ventilation, and have a long PICU stay and had a higher mortality rate than those in the non-ARDS group (all P &lt; 0.05). After LASSO, VIF, and manual screenings, six key variables were included in the binary logistic regression, of which five were associated with post-drowning ARDS: drowning duration ≥ 5 min (odds ratio [OR], 2.731; 95% confidence interval [CI], 1.132–6.589; P = 0.025), Pediatric Critical Illness Score (PCIS) (OR, 0.889; 95% CI, 0.848–0.933; P &lt; 0.001), neutrophil-to-lymphocyte ratio (NLR) (OR, 1.536; 95% CI, 1.208–1.952; P &lt; 0.001), lactate level (OR, 1.929; 95% CI, 1.465–2.540; P &lt; 0.001), and a white-out appearance on chest radiography (OR, 5.369; 95% CI, 1.990–14.482; P &lt; 0.001). <bold>Conclusions:</bold> Children with versus without post-drowning ARDS have more severe illness and are more likely to develop concomitant infections and MODS. Greater vigilance for post-drowning ARDS is warranted in children with a drowning duration ≥ 5 min, elevated NLR, elevated lactate level, lower PCIS, and white-out appearance on chest radiography. </p>