Dyspnea and Dyspnea-Associated Anxiety in the ICU Patient Population: A Narrative Review for CL Psychiatrists.

BACKGROUND: Consultation-liaison psychiatrists frequently address dyspnea in intensive care unit (ICU) patients. Dyspnea is common in this patient population, but is frequently misunderstood and underappreciated in noncommunicative ICU patients. OBJECTIVE: This paper provides an updated review on dyspnea specifically in the ICU population, including its pathophysiology and management, pharmacological and nonpharmacological, aimed at consultation-liaison psychiatrists consulting in ICU. METHODS: A literature review was conducted with PubMed, querying published articles for topics associated with dyspnea and dyspnea-associated anxiety in ICU patient populations. When literature in ICU populations was limited, information was deduced from dyspnea and anxiety management from non-ICU populations. Articles discussing the definition of dyspnea, mechanistic pathways, screening tools, and pharmacologic and nonpharmacologic management were included. RESULTS: A reference guide was created to help consultation-liaison psychiatrists and intensivists in the screening and treatment of dyspnea and dyspnea-associated anxiety in critically ill patients. CONCLUSIONS: Dyspnea is frequently associated with anxiety, prolonged days on mechanical ventilation, and worse quality of life after discharge. It can also increase the risk of posttraumatic stress disorder post-ICU discharge. However, it is not routinely screened for, identified, or addressed in the ICU. This manuscript provides an updated review on dyspnea and dyspnea-associated anxietyin the ICU population, including its pathophysiology and management, and offers a useful reference for consultation-liaison psychiatrists to provide treatment recommendations.

Diagnostic Accuracy of Thoracic Ultrasonography to Differentiate Transudative From Exudative Pleural Effusion.

BACKGROUND: There are limited data examining the diagnostic accuracy of thoracic ultrasonography (TUS) in distinguishing transudative from exudative pleural effusions. RESEARCH QUESTION: What is the diagnostic accuracy of TUS in distinguishing transudative from exudative effusions in consecutive patients with pleural effusion? STUDY DESIGN AND METHODS: Consecutive patients who underwent TUS and subsequently a diagnostic thoracentesis with a pleural fluid analysis were identified. TUS images of the pleural effusions were interpreted by previously published criteria. We evaluated the diagnostic performance of TUS findings in predicting a transudative vs exudative pleural effusions and specific pleural diagnoses. RESULTS: We evaluated 300 consecutive pleural effusions in 285 patients. The pleural effusions were classified as exudative in 229 of 300 cases (76%). TUS showed anechoic effusions in 122 of 300 cases (40%) and complex effusions in 178 of 300 cases (60%). An anechoic appearance on TUS was associated with exudative effusions (68/122; 56%) as compared with transudative effusions (54/122; 44%). The presence of a complex-appearing effusion on TUS was highly predictive of an exudative effusion (positive predictive value of 90%). However, none of the four TUS characteristics were highly specific of a pleural diagnosis. INTERPRETATION: Thoracic ultrasonography is inadequate to diagnose a transudative pleural effusion reliably. Although the TUS findings of a complex effusion may suggest an exudative pleural effusion, specific pleural diagnoses cannot be predicted confidently.

Temporal and spatial variations of greenhouse gas fluxes from a tidal mangrove wetland in Southeast China.

Tidal mangrove wetlands are a source of methane (CH4) and nitrous oxide (N2O); but considering the high productivity of mangroves, they represent a significant sink for carbon dioxide (CO2). An exotic plant Spartina alterniflora has invaded east China over the last few decades, threatening these coastal mangrove ecosystems. However, the atmospheric gas fluxes in mangroves are poorly characterized and the impact of biological invasion on greenhouse gas (GHG) fluxes in the wetland remains unclear. In this study, the temporal and spatial dynamics of key GHG fluxes (CO2, CH4, and N2O) at an unvegetated mudflat, cordgrass (S. alterniflora), and mangrove (Kandelia obovata) sites along an estuary of the Jiulong River in Southeast China were investigated over a 2-year period. The CO2 and CH4 fluxes demonstrated a seasonal and vegetation-dependent variation while N2O fluxes showed no such dependent pattern. Air temperature was the main factor influencing CO2 and CH4 fluxes. Cumulative global warming potential (GWP) ranked in the order of mangrove > cordgrass > mudflat and summer > spring > autumn > winter. Moreover, CH4 accounted for the largest proportion (68%) of GWP, indicating its dominant contribution to the warming potential in mangroves. Notwithstanding the lack of information on plant coverage, cordgrass invasion exhibited a minor influence on GHG emissions. These findings support the notion that mangrove forests are net accumulation sites for GHGs. As vegetation showed considerable effects on fluxes, more information about the significance of vegetation type with a special emphasis on the effects of invasive plants is crucial.