Daily Respiratory Research Analysis

BACKGROUND: There is uncertainty whether the use of selective decontamination of the digestive tract (SDD) as a preventive antimicrobial strategy reduces mortality in adult patients receiving mechanical ventilation in the intensive care unit (ICU). Following the publication of new data from a contemporary randomized clinical trial, an updated systematic review and meta-analysis was conducted to determine whether the use of SDD reduced hospital mortality compared to standard care. METHODS: An updated systematic review of a previously published meta-analysis was conducted including a search from September 12, 2022, to August 18, 2025, for randomized clinical trials (RCTs) of adults receiving mechanical ventilation in an ICU that compared SDD to standard care. Data were pooled using a Bayesian framework. The primary outcome was hospital mortality or closest approximation. RESULTS: One additional trial was identified, giving a total of 32 RCTs (27,687 participants), with 30 of the 32 RCTs (27,332 participants) contributing data to the primary outcome. The pooled estimated relative risk of hospital mortality for SDD compared to usual care or placebo was 0.91; 95% credible interval, 0.82 to 0.99, CONCLUSIONS: There is a high probability that in mechanically ventilated adults in the ICU, SDD, compared to standard care, is associated with a reduction in the risk of in-hospital death.

STUDY OBJECTIVES: To elucidate the neural mechanisms underlying hypercapnia triggered micro-arousal events during sleep apnea, focusing on neuronal activation and synaptic functions in medial parabrachial nucleus (MPB). METHODS: Mice underwent hypercapnic challenges to induce micro-arousal events, which were recognized by cortical EEG and hippocampal local field potential (LFP) during NREM sleep. Neuronal activation was quantified via Fos immunohistochemistry in MPB. Neuronal excitability and spontaneous excitatory postsynaptic current (sEPSC) under hypercapnia in MPB slices were assessed by whole-cell patch-clamp recording. RESULTS: Hypercapnia was proved to trigger micro-arousal events in vivo experiment, which were characterized by rapid cortical EEG/hippocampal LFP desynchronization. We found reduced delta and theta cortical power and suppressed hippocampal gamma and ripple oscillations with elevated EMG activity after hypercapnia. Moreover, hypercapnia increased Fos expressions in MPB neurons of mice. Furthermore, in vitro experiment, hypercapnic ACSF enhanced firing frequency and increased sEPSC frequency. However, the effects were abolished by NMDA/AMPA receptor blockade in the MPB slices. CONCLUSIONS: The differential cortical-hippocampal spectral responses and MPB activation reveal hypercapnia effects during sleep apnea, which suggests therapeutic targets for sleep breathing-related disorders.

BACKGROUND: It remains uncertain whether type 2 (T2) inflammation is associated with clinical outcomes during triple therapy in Chronic obstructive pulmonary disease (COPD) and whether asthma-COPD overlap (ACO) definitions add prognostic value beyond T2 biomarkers. METHODS: This prospective cohort enrolled 201 stable COPD patients scheduled to initiate triple therapy. Patients were classified into T2-high and T2-low groups based on blood eosinophils, FeNO, and sputum eosinophils. Outcomes at 1 year included CAT, SGRQ-C, FEV RESULTS: Within this cohort, T2-high was independently associated with better 1-year outcomes: lower CAT (AMD -2.31, 95% CI -3.73 to -0.88) and SGRQ-C (AMD -7.54, -11.38 to -3.70), and higher FEV CONCLUSION: Baseline T2-high status was associated with more favorable 1-year clinical outcomes during triple therapy, whereas adding ACO definitions to T2 stratification provided limited incremental prognostic value.