Chest
-
Bronchial thermoplasty (BT) involves the application of radiofrequency energy to visible proximal airways to selectively ablate airway smooth muscle. BT is the first nonpharmacologic interventional therapy approved by the US Food and Drug Administration (FDA) for severe asthma. This approval was based on the results of the pivotal Asthma Intervention Research (AIR)-2 trial, which is the only randomized, double-blind, sham-controlled trial of BT. ⋯ Did the AIR-2 trial include patients with a low FEV1, oral steroid dependence, or frequent exacerbations? Did the trial show efficacy for any of the primary or secondary end points? The FDA approved the device based on the reduction in severe asthma exacerbations. However, were the rates of asthma exacerbations, ED visits, or hospitalizations truly different between the two groups, and was this type of analysis even justified given the original study design? This commentary is designed to specifically answer these questions and help the practicing clinician navigate the thermoplasty literature with confidence and clarity. We carefully dissect the design, conduct, and results of the AIR-2 trial and raise serious questions about the efficacy of bronchial thermoplasty.
-
Randomized Controlled Trial Multicenter Study
Ventilator-associated pneumonia during weaning from mechanical ventilation: role of fluid management.
Pulmonary edema may alter alveolar bacterial clearance and infectivity. Manipulation of fluid balance aimed at reducing fluid overload may, therefore, influence ventilator-associated pneumonia (VAP) occurrence in intubated patients. The objective of the present study was to assess the impact of a depletive fluid-management strategy on ventilator-associated complication (VAC) and VAP occurrence during weaning from mechanical ventilation. ⋯ Using proper competing risk analyses, we found that a depletive fluid-management strategy, when initiating the weaning process, has the potential for lowering VAP risk in patients who are mechanically ventilated.
-
The advent of techniques such as microarrays and high-throughput sequencing has revolutionized our ability to examine messenger RNA (mRNA) expression within the respiratory system. Importantly, these approaches have also uncovered the widespread expression of "noncoding RNAs," including microRNAs and long noncoding RNAs, which impact biologic responses through the regulation of mRNA transcription and/or translation. To date, most studies of the role of noncoding RNAs have focused on microRNAs, which regulate mRNA translation via the RNA interference pathway. ⋯ Because these investigations into long noncoding RNAs were performed almost exclusively in non-small cell lung cancer, future work will need to extend these into other respiratory diseases and to analyze how microRNAs and long noncoding RNAs interact to regulate mRNA expression. From a clinical perspective, the targeting of noncoding RNAs as a novel therapeutic approach will require a deeper understanding of their function and mechanism of action. However, in the short term, changes in miRNA and long noncoding RNA expression are likely to be of use as biomarkers for disease stratification and/or assessment of drug action.