(a) Based on mechanistic meta-analyses in patients with sleep apnea, acetazolamide primarily causes a left-shift of the chemosensitivity line thus lowering plant gain without substantially affecting ...

Hematopoietic stem cell transplants (HSCT) are becoming more widespread as a result of optimization of conditioning regimens and prevention of short-term complications with prophylactic antibiotics and antifungals. However, pulmonary complications post-HSCT remain a leading cause of morbidity and mortality and are a challenge to clinicians in both diagnosis and treatment. This comprehensive review provides a primer for non-pulmonary healthcare providers, synthesizing the current evidence behind common infectious and non-infectious post-transplant pulmonary complications based on time (peri-engraftment, early post-transplantation, and late post-transplantation). Utilizing the combination of timing of presentation, clinical symptoms, histopathology, and radiographic findings should increase rates of early diagnosis, treatment, and prognostication of these severe illness states.

Our data provide important insights into obesity-related obstructive sleep apnea (OSA) pathogenesis, thereby validating, and extending, prior research findings. This is the largest sample size study to examine the relationships between obesity and gender on OSA pathogenesis. The influence of obesity on sleep apnea severity is mediated by different mechanistic traits (endotypes).

Rationale: Randomized trials have shown inconsistent cardiovascular benefits from obstructive sleep apnea (OSA) therapy. Intermittent hypoxemia can increase both sympathetic nerve activity and loop gain (“ventilatory instability”), which may thus herald cardiovascular treatment benefit. Objectives: To test the hypothesis that loop gain predicts changes in 24-hour mean blood pressure (MBP) in response to OSA therapy and compare its predictive value against that of other novel biomarkers. Methods: The HeartBEAT (Heart Biomarker Evaluation in Apnea Treatment) trial assessed the effect of 12 weeks of continuous positive airway pressure (CPAP) versus oxygen versus control on 24-hour MBP. We measured loop gain and hypoxic burden from sleep tests and identified subjects with a sleepy phenotype using cluster analysis. Associations between biomarkers and 24-h MBP were assessed in the CPAP/oxygen arms using linear regression models adjusting for various covariates. Secondary outcomes and predictors were analyzed similarly. Results: We included 93 and 94 participants in the CPAP and oxygen arms, respectively. Overall, changes in 24-hour MBP were small, but interindividual variability was substantial (mean [standard deviation], −2 [8] and 1 [8] mm Hg in the CPAP and oxygen arms, respectively). Higher loop gain was significantly associated with greater reductions in 24-hour MBP independent of covariates in the CPAP arm (−1.5 to −1.9 mm Hg per 1-standard-deviation increase in loop gain; P ⩽ 0.03) but not in the oxygen arm. Other biomarkers were not associated with improved cardiovascular outcomes. Conclusions: To our knowledge, this is the first study suggesting that loop gain predicts blood pressure response to CPAP therapy. Eventually, loop gain estimates may facilitate patient selection for research and clinical practice. Clinical trial registered with www.clinicaltrials.gov (NCT01086800).

Introduction The recent continuous positive airway pressure (CPAP) crisis has highlighted the need for alternative obstructive sleep apnea (OSA) therapies. This article serves to review OSA pathophysiology and how sleep apnea mechanisms may be utilized to individualize alternative treatment options. Areas covered: The research highlighted below focuses on 1) mechanisms of OSA pathogenesis and 2) CPAP alternative therapies based on mechanism of disease. We reviewed PubMed from inception to July 2022 for relevant articles pertaining to OSA pathogenesis, sleep apnea surgery, as well as sleep apnea alternative therapies. Expert opinion: Although the field of individualized OSA treatment is still in its infancy, much has been learned about OSA traits and how they may be targeted based on a patient’s physiology and preferences. While CPAP remains the gold-standard for OSA management, several novel alternatives are emerging. CPAP is a universal treatment approach for all severities of OSA. We believe that a personalized approach to OSA treatment beyond CPAP lies ahead. Additional research is needed with respect to implementation and combination of therapies longitudinally, but we are enthusiastic about the future of OSA treatment based on the data presented here.