Daily Ards Research Analysis
Analyzed 12 papers and selected 3 impactful papers.
Summary
Among 12 ARDS-related papers, three stood out: a large prospective cohort clarifying perioperative pulmonary risk after recent COVID-19, an in vivo porcine study showing dose-dependent benefits of intrabronchial surfactant after lung contusion, and a dual-center retrospective analysis indicating physiologic gains but no survival benefit with APRV. Together, they refine perioperative timing, suggest a translational surfactant strategy in trauma-related lung injury, and underscore the need for protocolized ventilation trials.
Research Themes
- Perioperative pulmonary risk after recent COVID-19 (including ARDS as a PPC)
- Translational surfactant therapy for trauma-related lung injury
- Optimization and timing of APRV (TCAV protocol) in ARDS management
Selected Articles
1. Association between preoperative COVID-19 and major postoperative pulmonary complications: a multicentre observational cohort study in China.
In a prospective multicentre cohort of 3211 elective surgery patients during the Omicron wave, preoperative COVID-19 within 12 weeks did not increase major PPC risk overall. However, surgery within 3 weeks of infection was independently associated with higher PPC risk, with cardiothoracic procedures showing elevated risk up to 7 weeks.
Impact: This study refines perioperative timing after COVID-19 by showing no overall risk increase within 12 weeks but identifying very short infection-to-surgery intervals and cardiothoracic surgery as higher-risk scenarios.
Clinical Implications: Use individualized perioperative risk assessment rather than blanket delays: consider deferring elective surgery at least 3 weeks after COVID-19, and up to 7 weeks for cardiothoracic cases, while optimizing baseline pulmonary risk and operative duration.
Key Findings
- No overall increase in 30-day major PPC with preoperative COVID-19 within 12 weeks (adjusted OR 0.89; 95% CI 0.69–1.13).
- Infection-to-surgery interval <3 weeks independently increased PPC risk (OR 3.44; 95% CI 1.37–8.68).
- Cardiothoracic surgery strongly associated with PPC (OR 12.47; 95% CI 8.11–19.17), with elevated risk within 7 weeks of infection.
- No significant differences in hospital LOS, reoperation, or mortality by preoperative COVID-19 status.
Methodological Strengths
- Prospective multicentre cohort design with large sample size (n=3211).
- Robust statistical adjustment including IPTW and multivariable analyses.
Limitations
- Observational design with potential residual confounding.
- Conducted during the Omicron wave in Beijing; generalizability to other settings/variants may be limited.
Future Directions: External validation in diverse regions and variants, integration of vaccination status and severity, and surgery-type–specific risk models to refine timing recommendations.
OBJECTIVE: To evaluate the relationship between preoperative COVID-19 infection and major postoperative pulmonary complications (PPC) risk after major elective surgeries during the Omicron wave. DESIGN: A multicentre, prospective, observational cohort study. SETTING: Four tertiary medical centres in Beijing, China. PARTICIPANTS: All adult patients who underwent major elective surgeries under general anaesthesia from 30 December 2022 to 18 May 2023 were screened for eligibility. A total of 3211 patients were included. PRIMARY AND SECONDARY MEASURES: The primary outcome was 30-day major PPC, defined as pneumonia, acute respiratory distress syndrome or unexpected postoperative ventilation. The secondary outcomes included length of hospital stay (LOS), reoperation and mortality. RESULTS: Major PPC occurred in 3.5% of patients with preoperative COVID-19 and 3.3% of those without. Inverse probability of treatment weighting-adjusted analysis showed no significant association between preoperative COVID-19 within 12 weeks and PPC risk (adjusted OR, 0.89; 95% CI 0.69 to 1.13). However, multivariable analysis revealed that COVID-19 infection within 3 weeks was independently associated with an increased PPC risk (OR, 3.44; 95% CI 1.37 to 8.68). Cardiothoracic surgery (OR, 12.47; 95% CI 8.11 to 19.17) and longer duration of surgery (OR, 1.24 per hour; 95% CI 1.13 to 1.37) were significant risk factors. In the cardiothoracic subgroup, PPC risk was significantly elevated within 7 weeks of infection. No significant differences were observed in LOS, reoperation rates or mortality between patients with and without preoperative COVID-19 infection. CONCLUSIONS: Preoperative COVID-19 infection within 12 weeks was not associated with an increased overall risk of major PPC during the Omicron wave. Although very short infection-to-surgery intervals and cardiothoracic surgery showed exploratory signals of higher risk, these findings should be interpreted cautiously and support an individualised approach to perioperative risk assessment. TRIAL REGISTRATION NUMBER: ChiCTR2200067250.
2. Dose-dependent effects of intrabronchially administered exogenous surfactant in a porcine model of lung contusion.
In a randomized porcine lung contusion model, intrabronchial Curosurf 10 mg/kg improved regional ventilation and reduced ventilatory ratio and PaCO2 over 6 hours, with a trend toward better oxygenation; 5 mg/kg had no significant effect.
Impact: Provides dose-response and regional ventilation evidence supporting early intrabronchial surfactant as a mechanistically rational intervention after chest trauma, informing design of translational trials.
Clinical Implications: While preclinical, findings support testing targeted intrabronchial surfactant (around 10 mg/kg) alongside lung-protective ventilation in severe chest trauma at high risk for ARDS.
Key Findings
- 10 mg/kg intrabronchial Curosurf improved regional ventilation in the contused lung.
- Ventilatory ratio and PaCO2 were lower with 10 mg/kg, indicating more efficient ventilation.
- Trend toward improved PaO2 at FiO2=1 at later time points in the 10 mg/kg group.
- No significant physiologic effects were observed with 5 mg/kg.
Methodological Strengths
- Randomized allocation to three groups with standardized lung contusion model.
- Use of electrical impedance tomography for real-time regional ventilation assessment over 6 hours.
Limitations
- Short 6-hour follow-up limits assessment of durability and outcomes.
- Small sample size and preclinical animal model may limit generalizability to humans.
Future Directions: Evaluate optimal dose, timing, and delivery in larger preclinical models and proceed to early-phase clinical trials in severe chest trauma/at-risk ARDS populations.
BACKGROUND: Surfactant dysfunction contributes to acute respiratory failure following lung contusion. Our experimental study aimed to determine whether exogenous surfactant administration improves regional ventilation and gas exchange in a porcine model of lung contusion. METHODS: Lung contusion was induced in pigs (n=21) using a custom forceps instrument. Animals were randomized into three equal groups. The two treated groups received Curosurf® intrabronchially (5 mg/kg or 10 mg/kg) 30 minutes post-contusion, while the third group served as a control. Vital signs, blood gases, and regional tidal volume distribution via electrical impedance tomography (primary outcome) were monitored for 6 hours. RESULTS: A sustained improvement in regional ventilation of the contused lung region, accompanied by more efficient ventilation, evidenced by a lower ventilatory ratio and PaCO2, was observed in the 10 mg/kg group. A trend toward improvement in systemic oxygenation (PaO2 at FiO2=1) was also noted in this group at later time points. The 5 mg/kg dose showed no significant effects. CONCLUSIONS: Early intrabronchial surfactant administration (10 mg/kg) was associated with improved regional ventilation and overall ventilation efficiency in the porcine lung contusion model. These findings suggest potential benefits for managing lung mechanics after severe chest trauma. (J Trauma Acute Care Surg. 2026;00: 000-000. Copyright © 2026 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the American Association for the Surgery of Trauma.).
3. Influence of airway pressure release ventilation on pulmonary gas exchange using ventilatory ratio.
In a dual-center retrospective cohort (n=107), APRV showed no survival advantage over LTVV as a primary strategy (44% vs 42% survival). When applied for ≥72 hours and according to TCAV, APRV improved gas exchange and ventilatory efficiency metrics, suggesting potential benefits if used early and protocolized.
Impact: Provides pragmatic, negative-yet-informative evidence that APRV may improve physiology without improving survival, underscoring the need for standardized early application and prospective trials.
Clinical Implications: APRV can be considered early and with TCAV protocol to improve gas exchange in ARDS but should not be expected to confer survival benefit; careful patient selection and monitoring of ventilatory ratio and oxygenation are warranted.
Key Findings
- No significant survival difference between APRV (44%) and LTVV (42%) as primary ventilation strategies.
- APRV often used late or as rescue; early, TCAV-adherent use improved gas exchange and ventilation efficiency.
- Physiologic metrics (e.g., ventilatory ratio, PaO2/FiO2) improved over ≥72 hours in APRV subgroup.
Methodological Strengths
- Dual-center dataset with defined APRV duration subgroup (≥72 h) and protocol adherence (TCAV).
- Use of ventilatory ratio and oxygenation indices as objective physiologic endpoints.
Limitations
- Retrospective design with selection bias and heterogeneity in APRV application.
- Small subgroup sizes and potential confounding limit inference on survival.
Future Directions: Prospective, protocolized RCTs comparing early TCAV-guided APRV versus LTVV with standardized implementation and patient-centered outcomes.
BACKGROUND: The COVID-19 pandemic led to a surge in Acute Respiratory Distress Syndrome (ARDS) cases. Despite important advances in ventilation strategies, ARDS mortality remains high. Airway Pressure Release Ventilation (APRV), especially when used according to the Time-Controlled Adaptive Ventilation (TCAV) protocol, has shown potential in improving oxygenation and reducing mortality in ARDS. METHODS: This retrospective dual-center study included patients with moderate to severe ARDS, who were treated with APRV or Low Tidal Volume Ventilation (LTVV) between January 2018 and March 2022. Individuals receiving APRV for at least 72 h after previously receiving LTVV were analyzed in further detail. PaO RESULTS: Out of 107 patients, 48 received APRV. In 27 cases, APRV was applied according to TCAV-protocol. APRV was often used late in treatment or as a rescue therapy. Regarding the primary ventilation strategy, there was no significant difference in survival between APRV (44%) and LTVV (42%). In patients receiving APRV for at least 72 h after being initially ventilated with LTVV ( CONCLUSION: APRV demonstrated potential in improving gas exchange and ventilation efficiency in ARDS patients, particularly when used early and according to TCAV. However, no survival benefit was observed. The study's retrospective design and heterogeneity in APRV application limit its conclusions.