Impact of Early Tracheostomy Versus Late or No Tracheostomy in Nonneurologically Injured Adult Patients: A Systematic Review and Meta-Analysis.

OBJECTIVE: The optimal timing of tracheostomy in nonneurologically injured mechanically ventilated critically ill adult patients is uncertain. We conducted a systematic review of randomized controlled trials to evaluate the effect of early versus late tracheostomy or prolonged intubation in this population. DATA SOURCES: We searched MEDLINE, Embase, CENTRAL, CINAHL, and Web of science databases for randomized controlled trials comparing early tracheostomy (<10 d of intubation) with late tracheostomy or prolonged intubation in adults. DATA SELECTION: We selected trials comparing early tracheostomy (defined as being performed less than 10 d after intubation) with late tracheostomy (performed on or after the 10th day of intubation) or prolonged intubation and no tracheostomy in nonneurologically injured patients. The primary outcome was overall mortality. Secondary outcomes included ventilator-associated pneumonia, duration of mechanical ventilation, ICU, and hospital length of stay. DATA EXTRACTION: Two reviewers screened citations, extracted data, assessed the risk of bias, and classification of Grading of Recommendations, Assessment, Development, and Evaluation independently. DATA SYNTHESIS: Our search strategy yielded 8,275 citations, from which nine trials (n = 2,457) were included. We did not observe an effect on the overall mortality of early tracheostomy compared with late tracheostomy or prolonged intubation (risk ratio, 0.91, 95% CI, 0.82-1.01; I2 = 18%). Our results were consistent in all subgroup analyses. No differences were observed in ICU and hospital length of stay, duration of mechanical ventilation, incidence of ventilator-acquired pneumonia, and complications. Our trial sequential analysis showed that our primary analysis on mortality was likely underpowered. CONCLUSION: In our systematic review, we observed that early tracheostomy, as compared with late tracheostomy or prolonged intubation, was not associated with a reduction in overall mortality. However, we cannot exclude a clinically relevant reduction in mortality considering the level of certainty of the evidence. A well-designed trial is needed to answer this important clinical question.

Tau positron emission tomography, cerebrospinal fluid and plasma biomarkers of neurodegeneration, and neurocognitive testing: an exploratory study of participants with myotonic dystrophy type 1.

OBJECTIVE: To investigate Tau pathology using multimodal biomarkers of neurodegeneration and neurocognition in participants with myotonic dystrophy type 1 (DM1). METHODS: We recruited twelve participants with DM1 and, for comparison, two participants with Alzheimer's Disease (AD). Participants underwent cognitive screening and social cognition testing using the Dépistage Cognitif de Québec (DCQ), among other tests. Biomarkers included Tau PET with [18F]-AV-1451, CSF (Aß, Tau, phospho-Tau), and plasma (Aß, Tau, Nf-L, GFAP) studies. RESULTS: Of the twelve DM1 participants, seven completed the full protocol (Neurocognition 11/12; PET 7/12, CSF 9/12, plasma 12/12). Three DM1 participants were cognitively impaired (CI). On average, CI DM1 participants had lower scores on the DCQ compared to cognitively unimpaired (CU) DM1 participants (75.5/100 vs. 91.4/100) and were older (54 vs. 44 years old) but did not differ in years of education (11.3 vs. 11.1). The majority (6/7) of DM1 participants had no appreciable PET signal. Only one of the CI participants presented with elevated Tau PET SUVR in bilateral medial temporal lobes. This participant was the eldest and most cognitively impaired, and had the lowest CSF Aß 1-42 and the highest CSF Tau levels, all suggestive of co-existing AD. CSF Tau and phospho-Tau levels were higher in the 3 CI compared to CU DM1 participants, but with a mean value lower than that typically observed in AD. Nf-L and GFAP were elevated in most DM1 participants (9/11 and 8/11, respectively). Finally, CSF phospho-Tau was significantly correlated with plasma Nf-L concentrations. CONCLUSIONS AND RELEVANCE: We observed heterogenous cognitive and biomarker profiles in individuals with DM1. While some participants presented with abnormal PET and/or CSF Tau, these patterns were highly variable and only present in a small subset. Although DM1 may indeed represent a non-AD Tauopathy, the Tau-PET tracer used in this study was unable to detect an in vivo Tau DM1 signature in this small cohort. Interestingly, most DM1 participants presented with elevated plasma Nf-L and GFAP levels, suggestive of other, possibly related, central brain alterations which motivate further research. This pioneering study provides novel insights towards the potential relationship between biomarkers and neurocognitive deficits commonly seen in DM1.