Heart-Brain 346-7 Score: the development and validation of a simple mortality prediction score for carbon monoxide poisoning utilizing deep learning.

INTRODUCTION: Acute mortality from carbon monoxide poisoning is 1-3%. The long-term mortality risk of survivors of carbon monoxide poisoning is doubled compared to age-matched controls. Cardiac involvement also increases mortality risk. We built a clinical risk score to identify carbon monoxide-poisoned patients at risk for acute and long-term mortality. METHODS: We performed a retrospective analysis. We identified 811 adult carbon monoxide-poisoned patients in the derivation cohort, and 462 adult patients in the validation cohort. We utilized baseline demographics, laboratory values, hospital charge transactions, discharge disposition, and clinical charting information in the electronic medical record in Stepwise Akaike's Information Criteria with Firth logistic regression to determine optimal parameters to create a prediction model. RESULTS: In the derivation cohort, 5% had inpatient or 1-year mortality. Three variables following the final Firth logistic regression minimized Stepwise Akaike's Information Criteria: altered mental status, age, and cardiac complications. The following predict inpatient or 1-year mortality: age > 67, age > 37 with cardiac complications, age > 47 with altered mental status, or any age with cardiac complications and altered mental status. The sensitivity of the score was 82% (95% confidence interval: 65-92%), the specificity was 80% (95% confidence interval: 77-83%), negative predictive value was 99% (95% confidence interval: 98-100%), positive predictive value 17% (95% confidence interval: 12-23%), and the area under the receiver operating characteristic curve was 0.81 (95% confidence interval: 0.74-0.87). A score above the cut-off point of -2.9 was associated with an odds ratio of 18 (95% confidence interval: 8-40). In the validation cohort (462 patients), 4% had inpatient death or 1-year mortality. The score performed similarly in the validation cohort: sensitivity was 72% (95% confidence interval: 47-90%), specificity was 69% (95% confidence interval: 63-73%), negative predictive value was 98% (95% confidence interval: 96-99%), positive predictive value was 9% (95% confidence interval: 5-15%) and the area under the receiver operating characteristic curve was 0.70 (95% confidence interval: 60%-81%). CONCLUSIONS: We developed and validated a simple, clinical-based scoring system, the Heart-Brain 346-7 Score to predict inpatient and long-term mortality based on the following: age > 67, age > 37 with cardiac complications, age > 47 with altered mental status, or any age with cardiac complications and altered mental status. With further validation, this score will hopefully aid decision-making to identify carbon monoxide-poisoned patients with higher mortality risk.

COVID-19 and the Early-Career Physician-Scientist. Fostering Resilience beyond the Pandemic.

The coronavirus disease (COVID-19) pandemic has created significant stressors for the academic and scientific community, with unique challenges for early-career physician-scientists. The pandemic-related disruptions have significantly affected research productivity, access to mentoring, professional development and networking opportunities, funding, and personal wellness. This is especially true for pulmonary and critical care medicine faculty because of the burden of specialized clinical care responsibilities that the COVID-19 pandemic has demanded. Departmental, institutional, and national leadership should foster open dialogue to identify and mitigate these challenges to promote ongoing career development of early-career physician-scientists. Implementation of thoughtful interventions to address these challenges will provide essential support for junior faculty and help retain a generation of physician-scientists.

Clinical Outcomes and Mortality Impact of Hyperbaric Oxygen Therapy in Patients With Carbon Monoxide Poisoning.

OBJECTIVES: Carbon monoxide poisoning affects 50,000 per year in the United States alone. Mortality is approximately 3%, and up to 40% of survivors suffer from permanent neurocognitive and affective deficits. Hyperbaric oxygen therapy has shown benefit on reducing the long-term neurologic sequelae of carbon monoxide poisoning but has not demonstrated improved survival. The objective of this study is to assess the efficacy of hyperbaric oxygen for acute and long-term mortality in carbon monoxide poisoning using a large clinical databank. DESIGN: Retrospective analysis. SETTING: University of Pittsburgh Medical Center healthcare system (Pittsburgh, PA). PATIENTS: One-thousand ninety-nine unique encounters of adult patients with carbon monoxide poisoning. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Baseline demographics, laboratory values, hospital charge transactions, discharge disposition, and clinical information from charting were obtained from the electronic medical record. In propensity-adjusted analysis, hyperbaric oxygen therapy was associated with a reduction in inpatient mortality (absolute risk reduction, 2.1% [3.7-0.9%]; p = 0.001) and a reduction in 1-year mortality (absolute risk reduction, 2.1% [3.8-0.4%]; p = 0.013). CONCLUSIONS: These data demonstrate that hyperbaric oxygen is associated with reduced acute and reduced 1-year mortality. Further studies are needed on the mortality effects of hyperbaric oxygen therapy in carbon monoxide poisoning.

IRF5 distinguishes severe asthma in humans and drives Th1 phenotype and airway hyperreactivity in mice.

Severe asthma (SA) is a significant problem both clinically and economically, given its poor response to corticosteroids (CS). We recently reported a complex type 1-dominated (IFN-γ-dominated) immune response in more than 50% of severe asthmatics despite high-dose CS treatment. Also, IFN-γ was found to be critical for increased airway hyperreactivity (AHR) in our model of SA. The transcription factor IRF5 expressed in M1 macrophages can induce a Th1/Th17 response in cocultured human T cells. Here we show markedly higher expression of IRF5 in bronchoalveolar lavage (BAL) cells of severe asthmatics as compared with that in cells from milder asthmatics or healthy controls. Using our SA mouse model, we demonstrate that lack of IRF5 in lymph node migratory DCs severely limits their ability to stimulate the generation of IFN-γ- and IL-17-producing CD4+ T cells and IRF5-/- mice subjected to the SA model displayed significantly lower IFN-γ and IL-17 responses, albeit showing a reciprocal increase in Th2 response. However, the absence of IRF5 rendered the mice responsive to CS with suppression of the heightened Th2 response. These data support the notion that IRF5 inhibition in combination with CS may be a viable approach to manage disease in a subset of severe asthmatics.

Nitrite reductase and nitric-oxide synthase activity of the mitochondrial molybdopterin enzymes mARC1 and mARC2.

Mitochondrial amidoxime reducing component (mARC) proteins are molybdopterin-containing enzymes of unclear physiological function. Both human isoforms mARC-1 and mARC-2 are able to catalyze the reduction of nitrite when they are in the reduced form. Moreover, our results indicate that mARC can generate nitric oxide (NO) from nitrite when forming an electron transfer chain with NADH, cytochrome b5, and NADH-dependent cytochrome b5 reductase. The rate of NO formation increases almost 3-fold when pH was lowered from 7.5 to 6.5. To determine if nitrite reduction is catalyzed by molybdenum in the active site of mARC-1, we mutated the putative active site cysteine residue (Cys-273), known to coordinate molybdenum binding. NO formation was abolished by the C273A mutation in mARC-1. Supplementation of transformed Escherichia coli with tungsten facilitated the replacement of molybdenum in recombinant mARC-1 and abolished NO formation. Therefore, we conclude that human mARC-1 and mARC-2 are capable of catalyzing reduction of nitrite to NO through reaction with its molybdenum cofactor. Finally, expression of mARC-1 in HEK cells using a lentivirus vector was used to confirm cellular nitrite reduction to NO. A comparison of NO formation profiles between mARC and xanthine oxidase reveals similar Kcat and Vmax values but more sustained NO formation from mARC, possibly because it is not vulnerable to autoinhibition via molybdenum desulfuration. The reduction of nitrite by mARC in the mitochondria may represent a new signaling pathway for NADH-dependent hypoxic NO production.