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Study Type: Prospective multicenter observational cohort study

Key Question: Does capnography-derived airway opening index (AOI) during paediatric CPR correlate with survival and neurological outcomes?

Key Findings:

• Among 99 cardiac arrest events, event-level AOI ≥0.35 was associated with improved survival to discharge (aRR 1.53, 95% CI 1.03–2.28, p=0.04) and favourable neurological outcome (aRR 1.56, 95% CI 1.01–2.41, p=0.04).
• Findings remained robust after excluding extracorporeal CPR cases.
• Post-arrest peak lactate was lower with AOI ≥0.35 (6.0 vs 11.5 mmol/L, p=0.006), despite similar CPR durations.

Clinical Relevance: AOI could serve as a real-time, capnography-based CPR quality metric guiding airway management and ventilation optimisation during paediatric resuscitation, relevant to UK PICU and resuscitation practice standards.

Limitations: Small sample size (99 events) from a non-UK cohort limits generalisability and precludes causal inference regarding AOI and outcome.

Study Type: Prospective, sham-controlled randomised trial (2:1 allocation)

Key Question: Does bronchoscopic metered cryospray (MCS) treatment improve quality of life and reduce exacerbations in COPD patients with chronic bronchitis compared with sham bronchoscopy plus mucus clearance?

Key Findings:

• MCS produced significantly greater improvement in SGRQ total score (treatment difference -5.9; 95% CI -11.6 to -0.2; p=0.042) and CAT score (-3.4; 95% CI -5.8 to -1.0; p=0.005) versus control.
• Severe AECOPD rates were numerically lower with MCS (21.3% vs 26.9%), though overall AECOPD rates were similar (70.6% vs 67.2%).
• Periprocedural pneumothorax occurred in 3.6% of MCS treatments; 8 deaths overall, none device/procedure-related.

Clinical Relevance: Offers a novel bronchoscopic option for symptomatic chronic bronchitis in COPD, a population with limited device-based therapies within current NHS respiratory pathways, though cost-effectiveness and NICE evaluation would be needed before adoption.

Limitations: Modest sample size and unblinded outcome assessment for exacerbations limit certainty around the modest treatment effect sizes and exacerbation benefit.

Study Type: Retrospective real-world cohort study (multinational registry analysis)

Key Question: Does smoking status (current/ex-smoker vs never-smoker) affect biologic treatment response in severe asthma, and does this influence prescribing practice across Europe?

Key Findings:

• Across all groups (never-, ex-, and current-smokers, n=3,876), 1-year biologic therapy improved symptom control (ACT/ACQ), reduced exacerbations, improved AQLQ, and reduced oral corticosteroid use, with no statistically significant difference in magnitude of improvement between groups.
• Current-smokers were under-represented among biologic recipients (n=141 vs 2,383 never-smokers).
• 29% of countries reported reluctance to prescribe biologics to current smokers; 59% expressed dissatisfaction with existing guideline recommendations on this issue.

Clinical Relevance: UK severe asthma services should not withhold biologics from smokers on efficacy grounds alone, as real-world data show comparable benefit, though smoking cessation support remains essential and current guidelines may need revision.

Limitations: Retrospective, non-randomised design with potential confounding and selection bias, limiting causal inference; RCTs in smokers are needed to confirm findings.

Study Type: Combined analysis of two replicate phase 3 RCTs (double-blind, placebo-controlled)

Key Question: Does inhaled treprostinil slow lung function decline and improve clinical outcomes in patients with idiopathic pulmonary fibrosis (IPF)?

Key Findings:

• FVC decline at 52 weeks was significantly attenuated with treprostinil vs placebo (-45.4 mL vs -161.7 mL; between-group difference 111.8 mL, 95% CI 79.7–144.0, p<0.0001).
• Treprostinil showed superiority in 5 of 6 secondary endpoints: time to clinical worsening, time to IPF exacerbation, K-BILD quality of life, ppDLCO and ppFVC.
• Fewer deaths with treprostinil (6.9% vs 9.4%); cough was the most frequent adverse event.

Clinical Relevance: These results, from the largest IPF pharmacotherapy trials to date, position inhaled treprostinil as a potential new disease-modifying option alongside antifibrotics, relevant to future NICE appraisal and UK ILD service commissioning.

Limitations: The abstract does not detail background antifibrotic use, blinding integrity (given cough as a side effect), or long-term safety beyond 52 weeks.

Study Type: Prospective community-based cohort study

Key Question: Are CT-detected airway mucus plugs associated with future respiratory outcomes in individuals with preserved spirometry and with COPD (including mild/asymptomatic disease)?

Key Findings:

• In preserved spirometry participants, ≥3 mucus plugs vs none: higher exacerbation risk (RR 1.42, 95%CI 1.11–1.81) and higher risk of developing spirometry-defined COPD (18.2% vs 7.6%; RR 1.71, 95%CI 1.05–2.78), plus faster FEV1/FVC decline.
• 1–2 mucus plugs also associated with modestly increased exacerbation risk (RR 1.22, 95%CI 1.01–1.48).
• In COPD (including mild-to-moderate and asymptomatic subgroups), ≥3 mucus plugs predicted greater total and moderate-to-severe exacerbation risk.

Clinical Relevance: Incidental mucus plugging on chest CT may identify pre-COPD/preserved-spirometry patients at risk of disease progression and exacerbations, supporting consideration of mucus plug burden as an early risk stratifier relevant to UK COPD case-finding and CT lung screening pathways.

Limitations: Observational Chinese cohort with potential residual confounding and uncertain generalisability to other ethnic populations and healthcare settings.

Study Type: Prospective cohort study (SPIROMICS)

Key Question: Does one-year progression of quantitative CT (QCT) emphysema measures predict subsequent FEV₁ decline in smokers with and without COPD?

Key Findings:

• In 880 participants, mean FEV₁ decline was -30.4 mL/year (95% CI -34.5, -26.3).
• Each SD increase in one-year progression of machine-learned emphysema subtypes predicted accelerated FEV₁ decline: combined bronchitic-apical emphysema (CBaE) -4.2 mL/year (95% CI -8.3, -0.2); diffuse emphysema -6.2 mL/year (95% CI -10.7, -1.8).
• Standard QCT emphysema metrics also predicted decline, but lost significance when modelled alongside CBaE and diffuse emphysema, which remained independent predictors.

Clinical Relevance: These CT-based emphysema subtypes could serve as short-term intermediate endpoints to accelerate COPD trial design and outcome assessment, relevant to UK respiratory research and future NHS-based imaging biomarker adoption.

Limitations: Observational design with QCT-based surrogate endpoints limits causal inference and generalisability to interventional trial settings.

Study Type: Qualitative study (secondary analysis of semi-structured interviews, directed content analysis)

Key Question: Does clinician regret influence VV ECMO candidacy decision-making?

Key Findings:

• Clinicians favour utility-based reasoning but often cannot apply it consistently due to uncertainty.
• Both regret of omission (not offering ECMO) and commission (offering ECMO) shape candidacy decisions.
• Clinicians use identifiable coping strategies to minimise anticipated and past regret, which may partly drive within-centre inconsistency in decisions.

Clinical Relevance: Understanding regret as a hidden driver of ECMO candidacy decisions is relevant to UK ECMO centres seeking to standardise selection criteria and reduce unwarranted variation in resource allocation.

Limitations: Small, international sample (n=24) using retrospective self-report limits generalisability and risks recall/social desirability bias.

Study Type: Retrospective registry-based cohort study (US CF Foundation Patient Registry, 2011–2019)

Key Question: Does inhaled antibiotic use in people with CF affect infection risk and lung function differently by Pseudomonas aeruginosa (Pa) status, and has this changed across CFTR-modulator eras?

Key Findings:

• Inhaled antibiotics were associated with increased risk of Aspergillus (HR 1.33, 95% CI 1.26–1.41), Stenotrophomonas maltophilia (HR 1.21, 1.14–1.29), and Achromobacter (HR 1.26, 1.14–1.39), with highest risk in Pa-negative patients.
• Lung function benefit from inhaled antibiotics was seen only in chronic Pa patients; Pa-negative patients showed lower lung function with treatment.
• Antibiotic-associated lung function benefit in chronic Pa patients diminished progressively across successive CFTR-modulator eras.

Clinical Relevance: Supports reassessment of chronic inhaled antibiotic prescribing in UK CF centres, particularly de-escalation in Pa-negative patients and modulator-treated populations, given diminishing benefit and rising non-fermenter/fungal infection risk.

Limitations: Observational registry design with potential residual confounding by indication despite inverse probability weighting.