Highlights
– Between 2007 and 2019, ARDS incidence among mechanically ventilated adult trauma patients documented in the NTDB fell from ~22 to ~3 per 100 ventilated patients, but crude ARDS mortality increased (15.1% to 29.7%).
– After multivariable adjustment, ARDS independently predicted 30‑day in‑hospital mortality (OR 1.32; 95% CI, 1.27–1.37). Key patient-level correlates included severe sepsis, ventilator‑associated pneumonia (VAP), and acute kidney injury (AKI); plasma and platelet transfusion volumes were associated with ARDS in the transfused subset.
– Care in centers affiliated with the Prevention and Early Treatment of Acute Lung Injury (PETAL) network and Extracorporeal Life Support Organization (ELSO) was associated with lower mortality (OR 0.78).
Background / Disease burden
Acute respiratory distress syndrome (ARDS) remains a major cause of morbidity and mortality in critically ill patients. Trauma is a well‑recognized precipitant of ARDS, with mechanisms including direct pulmonary contusion, transfusion‑related lung injury, systemic inflammatory responses, and secondary infections. Understanding temporal trends and determinants of ARDS in trauma populations is essential to target prevention and treatment strategies and to allocate regional critical care resources, including extracorporeal support.
Study design
This retrospective cohort study used the American College of Surgeons National Trauma Data Bank (NTDB) to examine adult injured patients (age ≥18) who received mechanical ventilation (MV) for ≥2 days between 2007 and 2019. Patients documented as having ARDS were compared with those without. A transfusion subset (patients with detailed transfusion data) was analyzed to evaluate associations between blood product exposure and ARDS. Multivariable logistic regression models adjusted for patient demographics, injury characteristics, center features, and blood products (in the transfusion subset). Primary endpoints included factors associated with an ARDS diagnosis and 30‑day in‑hospital mortality. No interventions were applied; this is an observational study of registry data.
Key findings
Incidence and temporal trends
Among 384,032 injured adults on MV for ≥2 days, ARDS was documented in 29,359 patients (approximately 8 per 100 ventilated patients overall). The documented incidence decreased substantially over the study period: roughly 22 per 100 ventilated patients in 2007 versus approximately 3 per 100 ventilated patients in 2019 (p < 0.001).
Independent risk factors for ARDS
After multivariable adjustment, several patient‑level factors were independently associated with higher odds of ARDS: blunt mechanism of injury (OR 1.25; 95% CI, 1.20–1.30), severe sepsis (OR 2.16; 95% CI, 2.06–2.27), ventilator‑associated pneumonia (VAP) (OR 2.91; 95% CI, 2.82–3.00), and acute kidney injury (AKI) (OR 2.98; 95% CI, 2.85–3.12). These associations were robust across annual models and highlight both primary injury patterns and common critical care complications as correlates of ARDS development.
Transfusion and ARDS
In the transfusion subset, increasing volumes of plasma and platelets administered within 24 hours were independently associated with ARDS (plasma OR 1.02 per unit; 95% CI, 1.01–1.04; platelets OR 1.03 per unit; 95% CI, 1.02–1.05). These findings are consistent with prior literature linking blood product exposure—particularly plasma and platelet transfusions—with heightened risk of transfusion‑related acute lung injury (TRALI) and ARDS in trauma patients.
Mortality trends and ARDS as an outcome predictor
Crude mortality among patients with ARDS increased during the study period—from 15.1% in 2007 to 29.7% in 2019 (p < 0.001). After adjusting for an array of confounders, ARDS remained independently associated with 30‑day in‑hospital mortality (OR 1.32; 95% CI, 1.27–1.37), indicating a persistent adverse prognostic impact attributable to ARDS beyond baseline injury severity and comorbidities.
Risk factors for mortality among patients with ARDS
Within the ARDS cohort, independent predictors of increased 30‑day mortality included head injury (OR 1.54; 95% CI, 1.43–1.66), severe sepsis (OR 1.48; 95% CI, 1.34–1.63), and AKI (OR 2.72; 95% CI, 2.50–2.96). These associations indicate that multisystem organ dysfunction and severe neurologic injury compound the mortality risk among patients who develop ARDS after trauma.
Center‑level associations
Management at centers affiliated with the PETAL network and ELSO was associated with lower odds of death (OR 0.78; 95% CI, 0.72–0.84). This suggests that institutional expertise, adherence to evidence‑based ARDS care pathways, and availability of advanced supportive therapies (including extracorporeal membrane oxygenation, ECMO) may confer survival benefits for selected patients.
Expert commentary and interpretation
The study leverages a large national registry to provide a detailed, longitudinal portrait of ARDS in the modern era of trauma care. Several interpretive points deserve emphasis.
Why might ARDS incidence fall while mortality rises?
The declining documented incidence could reflect improvements in early trauma resuscitation (e.g., damage control resuscitation, balanced transfusion strategies), broader adoption of lung‑protective ventilation outside randomized trials, prophylactic measures against VAP and sepsis, and perhaps evolving definitions or recognition thresholds over time. Conversely, rising crude ARDS mortality may reflect several, non‑mutually exclusive trends: survivors of the most severe early injuries may be living longer and thus are at risk of later ARDS with higher comorbidity burden; changes in coding or reporting that selectively capture sicker ARDS patients; concentration of care for the sickest patients at tertiary centers; or greater use of mechanical ventilation in patients with preexisting frailty. The adjusted association between ARDS and 30‑day mortality confirms that ARDS itself contributes to excess risk rather than being merely a marker of injury severity.
Transfusion findings and implications
The observed link between early plasma and platelet transfusion volumes and ARDS supports earlier signals that blood product exposure increases pulmonary risk. This reinforces ongoing efforts in trauma systems to optimize transfusion practices—minimizing unnecessary products, using pathogen‑reduced or male‑only plasma where appropriate, and continuing research into mechanisms of TRALI versus transfusion‑associated circulatory overload (TACO) and inflammation‑mediated lung injury.
Center expertise matters
Lower mortality at PETAL and ELSO centers suggests benefit from system‑level processes: protocolized ARDS care, multidisciplinary teams, access to ECMO, and participation in clinical networks that diffuse best practices. This finding supports regionalization or formal referral pathways for high‑risk trauma patients with refractory respiratory failure.
Limitations to consider
Important limitations temper causal inference. The NTDB relies on registry fields and clinical documentation; ARDS ascertainment was not necessarily standardized to the Berlin definition across centers or over time. The inclusion criterion of MV ≥2 days may introduce selection bias by excluding rapidly improving or early dying patients. Residual confounding is likely, particularly for unmeasured physiologic variables (ventilator settings, PaO2/FiO2 ratios, fluid balance) and illness severity metrics not uniformly captured. Temporal changes in diagnostic coding and center participation could influence trends. Finally, causality between transfusion volumes and ARDS cannot be established in this observational design.
Clinical and research implications
The analysis supports targeted, implementable strategies to reduce ARDS‑related mortality in trauma populations:
- Prioritize sepsis prevention and early recognition; aggressive source control and adherence to sepsis bundles may reduce ARDS risk and mortality.
- Maintain robust VAP prevention programs (e.g., ventilator bundles, subglottic secretion drainage) given the strong association between VAP and ARDS.
- Continued adherence to lung‑protective ventilation strategies and conservative fluid management where clinically feasible.
- Optimize transfusion practice: use balanced resuscitation protocols, minimize unnecessary plasma/platelet exposure, and implement hemovigilance measures.
- Develop regional care pathways to ensure timely access to high‑volume ARDS/ECMO centers and to disseminate PETAL‑network best practices.
Prospective studies should focus on mechanistic links between transfusion, inflammation, and lung injury; the impact of specific ventilator‑management protocols in trauma populations; and randomized or quasi‑experimental evaluation of system‑level interventions to reduce ARDS mortality.
Conclusion / Summary
This large NTDB cohort study (2007–2019) reports a marked decline in documented ARDS incidence among ventilated trauma patients but a paradoxical rise in crude ARDS mortality. ARDS independently predicted 30‑day in‑hospital death after adjustment for confounders. Key modifiable correlates include sepsis, VAP, AKI, and transfusion exposures; center characteristics and access to advanced support correlated with outcomes. These findings argue for intensified prevention efforts, optimization of transfusion and ventilator practices, and policies that promote rapid access to specialized ARDS care.
Funding and clinicaltrials.gov
Funding details and trial registration were not provided in the abstract. See the original publication for full disclosures.
References
1. Geng Z, Hynes AM, Moren AM, Christie JD, Mangalmurti NS, Li P, Gallagher JJ, Abella BS, Nam JJ, Schmulevich D, Nathens AB, Reilly PM, Zonies DH, Kaplan LJ, Cannon JW. Acute Respiratory Distress Syndrome in Trauma 2007-2019: Comprehensive Patient and Center-Level Retrospective Cohort Analysis. Crit Care Med. 2025 Nov 12. doi: 10.1097/CCM.0000000000006936. Epub ahead of print. PMID: 41222422.
2. Ranieri VM, Rubenfeld GD, Thompson BT, et al.; ARDS Definition Task Force. Acute respiratory distress syndrome: the Berlin Definition. JAMA. 2012;307(23):2526–2533.
3. Peek GJ, Mugford M, Tiruvoipati R, et al.; CESAR Trial Collaboration. Efficacy and economic assessment of conventional ventilatory support versus extracorporeal membrane oxygenation for severe adult respiratory failure (CESAR): a multicentre randomised controlled trial. Lancet. 2009;374(9698):1351–1363.
Additional relevant literature on transfusion‑related lung injury, ventilator bundles, and trauma resuscitation should be consulted for protocol development and local quality improvement initiatives.