Comparative outcomes between COVID-19 and influenza patients placed on veno-venous extracorporeal membrane oxygenation for severe ARDS

Background ECMO is an established supportive adjunct for patients with severe, refractory ARDS from viral pneumonia. However, the exact role and timing of ECMO for COVID-19 patients remains unclear. Methods We conducted a retrospective comparison of the first 32 patients with COVID-19-associated ARDS to the last 28 patients with influenza-associated ARDS placed on V-V ECMO. We compared patient factors between the two cohorts and used survival analysis to compare the hazard of mortality over sixty days post-cannulation.Results COVID-19 patients were older (mean 47.8 vs. 41.2 years, p = 0.033), had more ventilator days before cannulation (mean 4.5 vs. 1.5 days, p < 0.001). Crude in-hospital mortality was significantly higher in the COVID-19 cohort at 65.6% (n = 21/32) versus 36.3% (n = 11/28, p = 0.041). The adjusted hazard ratio over sixty days for COVID-19 patients was 2.81 (95% CI 1.07, 7.35) after adjusting for age, race, ECMO-associated organ failure, and Charlson Comorbidity Index. Conclusion ECMO has a role in severe ARDS associated with COVID-19 but providers should carefully weigh patient factors when utilizing this scarce resource in favor of influenza pneumonia

Time to Cannulation after ICU Admission Increases Mortality for Patients Requiring Veno-Venous ECMO for COVID-19 Associated Acute Respiratory Distress Syndrome

Objective: COVID-19 can cause acute respiratory distress syndrome (ARDS) that is rapidly progressive, severe, and refractory to conventional therapies. Extracorporeal membrane oxygenation (ECMO) can be used as a supportive therapy to improve outcomes but evidence-based guidelines have not been defined. Summary Background Data: Initial mortality rates associated with ECMO for ARDS in COVID-19 were high, leading some to believe that there was no role for ECMO in this viral illness. With more experience, outcomes have improved. The ideal candidate, timing of cannulation, and best post-cannulation management strategy, however, has not yet been defined. Methods: We conducted a retrospective review from April 1 to July 31 2020 of the first 25 patients with COVID-19 associated ARDS placed on V-V ECMO at our institution. We analyzed the differences between survivors to hospital discharge and those who died. Modified Poisson regression was used to model adjusted risk factors for mortality. Results: 44% of patients (11/25) survived to hospital discharge. Survivors were significantly younger (40.5 years vs. 53.1 years; p < 0.001) with no differences between cohorts in mean body mass index, diabetes, or PaO2:FiO2 at cannulation. Survivors had shorter duration from symptom onset to cannulation (12.5 days vs. 19.9 days, p = 0.028) and shorter duration of intensive care unit (ICU) length of stay (LOS) prior to cannulation (5.6 days vs. 11.7 days, p = 0.045). Each day from ICU admission to cannulation increased the adjusted risk of death by 4% and each year increase in age increased the adjusted risk 6%. Conclusions: ECMO has a role in severe, refractory ARDS associated with COVID-19. Increasing age and time from ICU admission were risk factors for mortality and should be considered in patient selection. Further studies are needed to define best practices for V-V ECMO use in COVID-19

Posthospitalization outcomes after extracorporeal membrane oxygenation (ECMO) for COVID-19

BACKGROUND: Critical illness from COVID-19 is associated with prolonged hospitalization and high mortality rates. Extracorporeal membrane oxygenation is used for refractory severe acute respiratory distress syndrome in COVID-19 with outcomes comparable to other indications for extracorporeal membrane oxygenation. However, long-term functional outcomes have yet to be fully elucidated. METHODS: We performed a retrospective chart review of 24 consecutive patients who required extracorporeal membrane oxygenation due to COVID-19 associated severe acute respiratory distress syndrome and survived to hospital discharge. After hospitalization, we contacted patients and administered the Patient-Reported Outcomes Measurement Information System (PROMIS) Global-10 tool to assess longer-term outcomes. We abstracted demographics, clinical course, outcomes, and disposition variables from the electronic medical record. Descriptive statistical analysis was used on the retrospective data collection. RESULTS: Inpatient data were analyzed for 24 patients, and 21 of 24 (88%) patients completed the Patient-Reported Outcomes Measurement Information System tool at an average of 8.8 months posthospitalization. At hospital discharge, 62.5% of patients had ongoing oxygen requirements (nasal cannula, trach collar, or mechanical ventilation); 70.8% were discharged to a location other than home. However, at the time of follow-up, only 9.5% of patients required supplemental oxygen, all tracheostomies had been removed, and all patients resided at home. Patients reported relatively high levels of global physical function, and though there was a high reported incidence of fatigue, overall pain scores were low. CONCLUSION: Long-term outcomes after extracorporeal membrane oxygenation for severe acute respiratory distress syndrome from coronavirus disease 2019 are promising. Extracorporeal membrane oxygenation therapy may confer morbidity benefits in patients with coronavirus disease and remains a valuable modality with excellent functional outcomes and preserved quality of life for survivors

Sediment Delivery to Sustain the Ganges-Brahmaputra Delta Under Climate Change and Anthropogenic Impacts

The principal nature-based solution for offsetting relative sea-level rise in the Ganges-Brahmaputra delta is the unabated delivery, dispersal, and deposition of the rivers’ ~1 billion-tonne annual sediment load. Recent hydrological transport modeling suggests that strengthening monsoon precipitation in the 21st century could increase this sediment delivery 34-60%; yet other studies demonstrate that sediment could decline 15-80% if planned dams and river diversions are fully implemented. We validate these modeled ranges by developing a comprehensive field-based sediment budget that quantifies the supply of Ganges-Brahmaputra river sediment under varying Holocene climate conditions. Our data reveal natural responses in sediment supply comparable to previously modeled results and suggest that increased sediment delivery may be capable of offsetting accelerated sea-level rise. This prospect for a naturally sustained Ganges-Brahmaputra delta presents possibilities beyond the dystopian future often posed for this system, but the implementation of currently proposed dams and diversions would preclude such opportunities

Cytokine Combination Therapy with Erythropoietin and Granulocyte Colony Stimulating Factor in a Porcine Model of Acute Myocardial Infarction

PurposeErythropoietin (EPO) and granulocyte colony stimulating factor (GCSF) have generated interest as novel therapies after myocardial infarction (MI), but the effect of combination therapy has not been studied in the large animal model. We investigated the impact of prolonged combination therapy with EPO and GCSF on cardiac function, infarct size, and vascular density after MI in a porcine model.MethodsMI was induced in pigs by a 90&nbsp;min balloon occlusion of the left anterior descending coronary artery. 16 animals were treated with EPO+GCSF, or saline (control group). Cardiac function was assessed by echocardiography and pressure-volume measurements at baseline, 1 and 6&nbsp;weeks post-MI. Histopathology was performed 6&nbsp;weeks post-MI.ResultsAt week 6, EPO+GCSF therapy stabilized left ventricular ejection fraction, (41 ± 1% vs. 33 ± 1%, p &lt; 0.01) and improved diastolic function compared to the control group. Histopathology revealed increased areas of viable myocardium and vascular density in the EPO+GCSF therapy, compared to the control. Despite these encouraging results, in a historical analysis comparing combination therapy with monotherapy with EPO or GCSF, there were no significant additive benefits in the LVEF and volumes overtime using the combination therapy.ConclusionOur findings indicate that EPO+GCSF combination therapy promotes stabilization of cardiac function after acute MI. However, combination therapy does not seem to be superior to monotherapy with either EPO or GCSF

Time to Cannulation after ICU Admission Increases Mortality for Patients Requiring Veno-Venous ECMO for COVID-19 Associated Acute Respiratory Distress Syndrome

COVID-19 can cause ARDS that is rapidly progressive, severe, and refractory to conventional therapies. ECMO can be used as a supportive therapy to improve outcomes but evidence-based guidelines have not been defined. SUMMARY BACKGROUND DATA: Initial mortality rates associated with ECMO for ARDS in COVID-19 were high, leading some to believe that there was no role for ECMO in this viral illness. With more experience, outcomes have improved. The ideal candidate, timing of cannulation, and best postcannulation management strategy, however, has not yet been defined. METHODS: We conducted a retrospective review from April 1 to July 31, 2020 of the first 25 patients with COVID-19 associated ARDS placed on V-V ECMO at our institution. We analyzed the differences between survivors to hospital discharge and those who died. Modified Poisson regression was used to model adjusted risk factors for mortality. RESULTS: Forty-four patients (11/25) survived to hospital discharge. Survivors were significantly younger (40.5 years vs 53.1 years; P < 0.001) with no differences between cohorts in mean body mass index, diabetes, or PaO2:-FiO2 at cannulation. Survivors had shorter duration from symptom onset to cannulation (12.5 days vs 19.9 days, P = 0.028) and shorter duration of intensive care unit (ICU) length of stay before cannulation (5.6 days vs 11.7 days, P = 0.045). Each day from ICU admission to cannulation increased the adjusted risk of death by 4% and each year increase in age increased the adjusted risk 6%. CONCLUSIONS: ECMO has a role in severe, refractory ARDS associated with COVID-19. Increasing age and time from ICU admission were risk factors for mortality and should be considered in patient selection. Further studies are needed to define best practices for V-V ECMO use in COVID-19

Combined Flux Chamber and Genomics Approach Links Nitrous Acid Emissions to Ammonia Oxidizing Bacteria and Archaea in Urban and Agricultural Soil

Nitrous acid (HONO) is a photochemical source of hydroxyl radical and nitric oxide in the atmosphere that stems from abiotic and biogenic processes, including the activity of ammonia-oxidizing soil microbes. HONO fluxes were measured from agricultural and urban soil in mesocosm studies aimed at characterizing biogenic sources and linking them to indigenous microbial consortia. Fluxes of HONO from agricultural and urban soil were suppressed by addition of a nitrification inhibitor and enhanced by amendment with ammonium (NH₄⁺), with peaks at 19 and 8 ng m^–2 s^–1, respectively. In addition, both agricultural and urban soils were observed to convert ¹⁵NH₄⁺ to HO¹⁵NO. Genomic surveys of soil samples revealed that 1.5–6% of total expressed 16S rRNA sequences detected belonged to known ammonia oxidizing bacteria and archaea. Peak fluxes of HONO were directly related to the abundance of ammonia-oxidizer sequences, which in turn depended on soil pH. Peak HONO fluxes under fertilized conditions are comparable in magnitude to fluxes reported during field campaigns. The results suggest that biogenic HONO emissions will be important in soil environments that exhibit high nitrification rates (e.g., agricultural soil) although the widespread occurrence of ammonia oxidizers implies that biogenic HONO emissions are also possible in the urban and remote environment