Daily Ards Research Analysis
Three studies highlight advances across acute and neonatal respiratory failure: a prospective ARDS cohort identifies angiopoietin-2 as a predictor of rapidly improving ARDS; a randomized neonatal study shows diaphragmatic ultrasound outperforms thoracic fluid content in predicting NIV failure; and a small antenatal RCT suggests melatonin may reduce intubation among preterm neonates with RDS despite no significant reduction in RDS incidence.
Summary
Three studies highlight advances across acute and neonatal respiratory failure: a prospective ARDS cohort identifies angiopoietin-2 as a predictor of rapidly improving ARDS; a randomized neonatal study shows diaphragmatic ultrasound outperforms thoracic fluid content in predicting NIV failure; and a small antenatal RCT suggests melatonin may reduce intubation among preterm neonates with RDS despite no significant reduction in RDS incidence.
Research Themes
- ARDS phenotyping and vascular biomarkers
- Point-of-care ultrasound for neonatal respiratory failure risk stratification
- Antenatal interventions for prevention of neonatal RDS
Selected Articles
1. The utility of angiopoietin-2 and blood cell-derived biomarker indices in differentiating rapidly improving acute respiratory distress syndrome (RIARDS) phenotype from persistent-ARDS: a prospective observational study.
In a prospective ARDS cohort (n=193), lower plasma angiopoietin-2 independently predicted the rapidly improving ARDS phenotype and was associated with better ICU survival. A cut-off of 5896 pg/mL yielded AUC 0.731 with high specificity (88.9%), supporting early biomarker-based prognostic enrichment.
Impact: Identifying RIARDS at presentation using a vascular leakage biomarker enables precision phenotyping, trial enrichment, and tailored ventilatory strategies. It addresses prognostic heterogeneity in ARDS.
Clinical Implications: Early Ang-2 measurement could guide expectations for rapid improvement, inform ventilator weaning trials, and prioritize resources, while supporting stratification in interventional studies.
Key Findings
- RIARDS occurred in 18.6% overall, most frequent in mild ARDS (52.9%) versus moderate (19.2%) and severe (10.4%).
- Angiopoietin-2 independently predicted RIARDS; a 5896 pg/mL cut-off achieved AUC 0.731 with 88.9% specificity and 57.3% sensitivity.
- Patients with Ang-2 <5896 pg/mL were more likely to experience RIARDS (86.1% vs 13.9%, p<0.001).
- RIARDS phenotype showed significantly better ICU survival on Kaplan–Meier analysis.
Methodological Strengths
- Prospective, consecutively enrolled cohort with standardized day-1 biomarker sampling
- Multivariable regression and ROC analysis with clinically interpretable cut-off
Limitations
- Single-center study without external validation; moderate AUC and modest sensitivity
- Observational design precludes causal inference; potential confounding remains
Future Directions: External validation, integration into multimarker panels and clinical scores, and use for prognostic enrichment in ARDS interventional trials.
BACKGROUND: Rapidly improving acute respiratory distress syndrome (RIARDS) is defined as normalization of oxygenation (PaO RESEARCH DESIGN AND METHODS: In this prospective observational study (June 2023-January 2025) at a 2032-bedded tertiary centre, 193 consecutively enrolled mechanically ventilated ARDS patients were assessed. Demographic, clinical, and laboratory data were recorded on Day 1. Plasma Ang-2 was measured using a high-sensitivity ELISA. Primary outcome was RIARDS; secondary outcome was ICU survival. RESULTS: RIARDS occurred in 18.6% of patients, highest in mild ARDS (52.9%) versus moderate (19.2%) and severe (10.4%). Multivariable regression identified Ang-2 as an independent predictor. A cut-off of 5896 pg/mL yielded an AUC of 0.731 (sensitivity 57.3%, specificity 88.9%). Patients with Ang-2 < 5896 pg/mL were more likely to develop RIARDS (86.1% vs. 13.9%, p-value < 0.001). Kaplan-Meier analysis showed significantly better ICU survival in RIARDS. CONCLUSIONS: Early Ang-2 measurement may help differentiate RIARDS from persistent ARDS, enabling prognostic enrichment and personalized management.
2. Diaphragmatic ultrasound and thoracic fluid content for prediction of non-invasive ventilation failure in neonates: a randomized controlled trial.
In a randomized neonatal cohort (n=90), diaphragmatic thickening fraction and excursion measured within 3 hours of life accurately predicted NIV failure, outperforming thoracic fluid content, with a combined DTF+TFC model reaching AUC 0.93. Findings support early bedside ultrasound to stratify risk during initial NIV.
Impact: This work operationalizes a practical, non-invasive prediction strategy leveraging point-of-care ultrasound, potentially reducing delayed intubation and complications in preterm RDS.
Clinical Implications: Incorporating early diaphragmatic ultrasound into standard neonatal NIV assessment may guide escalation decisions, optimize monitoring, and allocate higher-acuity care to high-risk infants.
Key Findings
- DTF and DE were significantly higher in NIV successes than failures (all p<0.001).
- DTF and DE achieved AUCs of 0.90 and 0.89, outperforming TFC (AUC 0.81).
- DTF (adjusted OR 0.89, 95% CI 0.83–0.96) and DE (adjusted OR 0.38, 95% CI 0.20–0.73) independently predicted NIV failure.
- Combined DTF+TFC model provided the highest discrimination (AUC 0.93, 95% CI 0.89–0.97).
Methodological Strengths
- Randomized allocation to NIV modes with standardized early measurements
- Use of objective ultrasound and electrical cardiometry with multivariable modeling and ROC analyses
Limitations
- Single-center, small sample size; limited power for clinical outcomes
- Trial registered late (August 22, 2025), raising concerns about preregistration and potential bias; external validation lacking
Future Directions: Multicenter validation, integration into decision algorithms for NIV escalation, and assessment of impact on clinical outcomes (intubation, BPD, mortality).
UNLABELLED: Non-invasive ventilation (NIV) remains the standard of care for preterm infants with respiratory distress syndrome (RDS); however, NIV failure is frequent and often linked to adverse outcomes. This study evaluated diaphragmatic ultrasound and thoracic fluid content (TFC) as early predictors of NIV failure in preterm neonates. In this prospective randomized controlled trial, 90 preterm neonates (28-34 gestational weeks) with RDS requiring NIV as initial respiratory support were randomized into three groups: (1) nasal continuous positive airway pressure (nCPAP), (2) nasal intermittent positive pressure ventilation (NIPPV), and (3) nasal high-frequency oscillatory ventilation (NHFOV). Diaphragmatic thickening fraction (DTF) and excursion (DE) were measured by ultrasound, while TFC was assessed using electrical cardiometry (EC). Measurements were obtained within the first 3 h of life and repeated either at 24 h in successful cases or immediately before intubation in failed cases. DTF and DE were significantly higher in neonates with successful NIV compared with those who failed (all p < 0.001), while TFC was significantly higher in failed cases within NIPPV and NHFOV groups (p < 0.001). DTF and DE showed excellent predictive accuracy (AUC 0.90 and 0.89), outperforming TFC (AUC 0.81, p < 0.01). Both DTF (adjusted OR = 0.89, 95% CI 0.83-0.96) and DE (adjusted OR = 0.38, 95% CI 0.20-0.73) independently predicted NIV failure. The combined DTF-TFC model provided the highest discrimination (AUC 0.93, 95% CI 0.89-0.97). CONCLUSIONS: Diaphragmatic ultrasound and TFC-derived EC represent simple, non-invasive, and reliable tools for predicting NIV failure in preterms with RDS. CLINICAL TRIAL REGISTRATION: clinicaltrials.gov/ NCT07148102; registered August 22, 2025. WHAT IS KNOWN: • NIV is widely used in preterm neonates with RDS, but predicting NIV failure remains challenging. Lung ultrasound score and thoracic fluid content have been explored as bedside predictors of NIV outcomes, with variable accuracy.. • Diaphragmatic ultrasound parameters (DTF and DE) have shown potential in assessing respiratory function in neonates. WHAT IS NEW: • DTF and DE measured by ultrasound show a strong correlation with TFC obtained by EC in predicting NIV failure. Additionally, DTF and DE have higher predictive accuracy than TFC in identifying preterm neonates at risk of NIV failure. • Early assessment of DTF and DE may serve as a valuable bedside tool for monitoring lung function during early application of NIV in preterm infants.
3. Efficacy of Melatonin Administration in Pregnancy in Prevention of Neonatal Respiratory Distress Syndrome in Preterm Neonates: A Randomized Controlled Trial.
In a single-blind RCT among women with placenta accreta spectrum (n=60), antenatal melatonin did not significantly reduce neonatal RDS incidence but was associated with lower intubation rates among infants who developed RDS. Findings are hypothesis-generating and warrant larger multicenter trials.
Impact: Despite a negative primary endpoint, the reduction in intubation among RDS cases suggests a clinically meaningful signal for an inexpensive, safe antenatal adjunct.
Clinical Implications: If validated, antenatal melatonin could be considered as an adjunct to corticosteroids in high-risk preterm deliveries to reduce invasive ventilation needs.
Key Findings
- RDS incidence: 16.7% with melatonin vs 30.0% control (p=0.228).
- Among neonates with RDS, intubation was 0% in melatonin vs 66.7% in control (p=0.016).
- Single-blind RCT design with 10 mg/day melatonin for two weeks before elective cesarean.
Methodological Strengths
- Randomized, controlled design with defined dosing protocol alongside standard antenatal steroids
- Clinically relevant outcomes assessed (RDS diagnosis, intubation)
Limitations
- Small sample size and single-blind design; primary outcome not statistically significant
- Specific high-risk population (placenta accreta spectrum) limits generalizability; short follow-up
Future Directions: Conduct adequately powered, multicenter, double-blind RCTs with longer follow-up to assess respiratory and neurodevelopmental outcomes.
OBJECTIVE: Respiratory Distress Syndrome (RDA) is a common complication in premature neonates due to immature lungs, and antenatal corticosteroid administration could reduce its incidence. We aim to investigate the role of antenatal melatonin administration in preventing RDS among women with placenta accrete spectrum who usually mandate early delivery. MATERIALS AND METHODS: This is a single-blinded randomized controlled trial performed in a tertiary hospital among women with placenta accrete spectrum. The melatonin group received Melatonin 10 mg/daily for two weeks before elective cesarean section in addition to corticosteroids, and the control group just received corticosteroids. The RDS occurrence was compared between two groups. RESULTS: In total, 60 participants were involved in the study (30 in the melatonin group and 30 in the control group). RDS was diagnosed for five (16.7%) neonates in the melatonin group and nine (30.0%) neonates in the control group (P-value= 0.228). Among neonates with RDS, no neonate in the melatonin group required intubation, and six (66.7%) neonates intubation needed in the control group (P = 0.016). CONCLUSION: Antenatal melatonin administration may reduce the need for intubation in preterm neonates with RDS, though the lower incidence of RDS observed in the melatonin group was not statistically significant. The small number of RDS cases limits the ability to draw definitive conclusions regarding intubation rates and hospitalization duration. Larger-scale, multicenter studies with long-term follow-up are needed to validate these findings and better understand melatonin's role in neonatal respiratory care.