Effects of short-term hyperoxia on erythropoietin levels and microcirculation in critically Ill patients: a prospective observational pilot study

BACKGROUND: The normobaric oxygen paradox states that a short exposure to normobaric hyperoxia followed by rapid return to normoxia creates a condition of 'relative hypoxia' which stimulates erythropoietin (EPO) production. Alterations in glutathione and reactive oxygen species (ROS) may be involved in this process. We tested the effects of short-term hyperoxia on EPO levels and the microcirculation in critically ill patients.METHODS: In this prospective, observational study, 20 hemodynamically stable, mechanically ventilated patients with inspired oxygen concentration (FiO2) \ue2\u89\ua40.5 and PaO2/FiO2\ue2\u80\u89\ue2\u89\ua5\ue2\u80\u89200\uc2\ua0mmHg underwent a 2-hour exposure to hyperoxia (FiO2 1.0). A further 20 patients acted as controls. Serum EPO was measured at baseline, 24\uc2\ua0h and 48\uc2\ua0h. Serum glutathione (antioxidant) and ROS levels were assessed at baseline (t0), after 2\uc2\ua0h of hyperoxia (t1) and 2\uc2\ua0h after returning to their baseline FiO2 (t2). The microvascular response to hyperoxia was assessed using sublingual sidestream dark field videomicroscopy and thenar near-infrared spectroscopy with a vascular occlusion test.RESULTS: EPO increased within 48\uc2\ua0h in patients exposed to hyperoxia from 16.1 [7.4-20.2] to 22.9 [14.1-37.2] IU/L (p\ue2\u80\u89=\ue2\u80\u890.022). Serum ROS transiently increased at t1, and glutathione increased at t2. Early reductions in microvascular density and perfusion were seen during hyperoxia (perfused small vessel density: 85% [95% confidence interval 79-90] of baseline). The response after 2\uc2\ua0h of hyperoxia exposure was heterogeneous. Microvascular perfusion/density normalized upon returning to baseline FiO2.CONCLUSIONS: A two-hour exposure to hyperoxia in critically ill patients was associated with a slight increase in EPO levels within 48\uc2\ua0h. Adequately controlled studies are needed to confirm the effect of short-term hyperoxia on erythropoiesis.TRIAL REGISTRATION: ClinicalTrials.gov ( www.clinicaltrials.gov ), NCT02481843 , registered 15th June 2015, retrospectively registered

Air Pollution, Aeroallergens, and Emergency Room Visits for Acute Respiratory Diseases and Gastroenteric Disorders among Young Children in Six Italian Cities

Past studies reported evidence of associations between air pollution and respiratory symptoms and morbility for children. Few studies examined associations between air pollution and emergency room (ER) visits for wheezing, and even fewer for gastroenteric illness. We conducted a multicity analysis of the relationship between air pollution and ER visits for wheezing and gastroenteric disorders in children 0-2 years of age.BACKGROUND: Past studies reported evidence of associations between air pollution and respiratory symptoms and morbidity for children. Few studies examined associations between air pollution and emergency room (ER) visits for wheezing, and even fewer for gastroenteric illness. We conducted a multicity analysis of the relationship between air pollution and ER visits for wheezing and gastroenteric disorder in children 0-2 years of age. METHODS: We obtained ER visit records for wheezing and gastroenteric disorder from six Italian cities. A cityspecific case-crossover analysis was applied to estimate effects of particulate matter (PM), nitrogen dioxide, sulfur dioxide, ozone, and carbon monoxide, adjusting for immediate and delayed effects of temperature. Lagged effects of air pollutants up to 6 prior days were examined. The cityspecific results were combined using a random-effect meta-analysis. RESULTS: CO and SO2 were most strongly associated with wheezing, with a 2.7% increase [95% confidence interval (CI), 0.5-4.9] for a 1.04 \u3bcg/m3 increase in 7day average CO and a 3.4% (95% CI, 1.5-5.3) increase for an 8.0 \u3bcg/m3 increase in SO2. Positive associations were also found for PM with aerodynamic diameter 64 10 \u3bcg and NO2. We found a significant association between the 3day moving average CO and gastroenteric disorders [3.8% increase (95% CI, 1.0-6.8)]. When data were stratified by season, the associations were stronger in summer for wheezing and in winter for gastroenteric disorders. CONCLUSION: Air pollution is associated with triggering of wheezing and gastroenteric disorders in children 0-2 years of age; more work is needed to understand the mechanisms to help prevent wheezing in children

LIBER AMICORUM PER ANTONIO MATACENA

Vi sono professori che per spessore scientifico, capacit\ue0 divulgativa e carisma personale si distinguono da tutti gli altri e divengono \u201cmaestri\u201d, proprio come l\u2019etimo della parola richiederebbe. Per questi \u2013 e solo per questi \u2013 \ue8 consuetudine che nell\u2019ultimo anno accademico di ruolo venga curato un libro collettaneo, per celebrare i contributi scientifici e la figura accademica del maestro. La forma pi\uf9 diffusa e istituzionale \ue8 quella degli Scritti in onore di. Chi conosce Antonio Matacena, tuttavia, sa bene che le soluzioni istituzionali e pi\uf9 rassicuranti mal si adattano alla sua personalit\ue0 e al suo impegno intellettuale, sempre attento alla \u201calterit\ue0\u201d e spesso anticonvenzionale. Abbiamo quindi ritenuto che un liber amicorum \u2013 in grado di ospitare contributi eterogenei e non solo accademici \u2013 fosse la soluzione pi\uf9 efficacie per rappresentare la passione per l\u2019insegnamento e la gioia della condivisione che, insieme all\u2019innovazione scientifica, hanno caratterizzato la vita del nostro Maestro Antonio Matacena. In particolare, questo volume pi\uf9 che essere un liber amicorum, vuole essere un liber ab amicis, ossia una testimonianza dagli amici per il prof. Matacena, per ringraziarlo del ruolo che ha saputo svolgere nella vita di ciascuno, come studioso e come docente