Solar photocatalysis application in UWWTP outlets - simulations based on predictive models in flat-plate reactors and pollutant degradation studies with in silico toxicity assessment

The application of the solar photocatalysis for the degradation of residual pollutants found in surface water was demonstrated. Semi-pilot scale flat-plate cascade reactor (FPCR) was used to study the degradation of model organic pollutants: enrofloxacin (ENRO), 17β-estradiol (E2) and 1H-benzotriazole (1H-BT) over TiO2 thin-film supported on glass fibers. A modular panel with full-spectra solar lamps with appropriate UVB and UVA irradiation levels was used as a simulation of sunlight. Pollutant degradation in FPCR was estimated using predictive models; intrinsic reaction rate constants (ki) for ENRO, E2 and 1H-BT independent of the reactor size, flow rate and irradiation conditions were determined: 9.60, 3.35 and 0.37 109 s-1 W-0.5 m1.5, respectively. Main degradation products (DPs), formed upon hydroxylation, ring opening and oxidation, were identified using LC-QTOF-MS. The ecotoxicological impact was assessed via T.E.S.T. and ECOSAR open-source tools showing the formation of less harmful DPs after sufficient reaction time. Pollutant degradation was simulated at four locations of interest, i.e. exhausts from urban wastewater treatment plants (UWWTPs) in Zagreb, Croatia (45°N), Krakow, Poland (50°N), Sevilla, Spain (37°N) and Ioannina, Greece (39.6°N). Results have proved that a simple flat-plate system with supported photocatalysts can be easily scaled up and incorporated at the outlet of UWWTP for the reduction of pollutant load and related toxicity. The exhaust canal in Zagreb with the estimated length of a photocatalytic layer of 122 m for the > 90% degradation of all target pollutants was discussed as the best installation site among studied locations. ENVIRONMENTAL IMPLICATION: A multi-disciplinary approach to the tentative application of TiO2 solar photocatalysis outdoors to reduce pollutant loads and toxicity in surface waters was demonstrated. Possible application at four selected locations in Europe, as an additional step in water treatment after urban wastewater treatment plants (UWWTPs) was discussed. Target pollutants were studied under environmentally relevant conditions (sunlight levels, water matrix, simulation of process on a real scale at selected geographical location), at both higher and low concentrations.

Intravenous infusion of angiotensin II for treatment of cardiopulmonary bypass-induced vasoplegic shock after implantation of left ventricular assist device: a case report

We report on the first successful treatment of severe pharmacoresistant vasoplegic syndrome with angiotensin II acetate (ATII) in Croatia. ATII is a novel drug used to treat severe vasoplegic shock resistant to the administration of catecholamines or alternative vasopressors such as vasopressin or methylene blue. A 44-year-old patient with secondary toxic cardiomyopathy developed severe cardiopulmonary bypass-induced vasoplegic shock after scheduled implantation of a left-ventricular assist device. The cardiac output was maintained, but systemic vascular resistance (SVR) was extremely low. The patient had an inadequate reaction to the administration of high doses of norepinephrine (up to 0.7 µg/kg/min) and vasopressin (0.03 IU/min). At postoperative intensive care unit (ICU) admission, serum renin levels were unmeasurably high (>330 ng/L), and infusion of ATII 20 ng/kg/min was initiated. Soon after the start of the infusion, blood pressure increased. Vasopressin infusion was stopped, while the norepinephrine dose was decreased from 0.7 to 0.15 µg/kg/min. Serum lactate, mixed venous saturation, and glomerular filtration rate markedly improved. The patient was extubated 16 h after the ICU admission. Twenty-four hours after the start of the ATII infusion, serum renin dropped to 255 ng/L, and laboratory findings further improved. On postoperative day 3, the norepinephrine infusion was stopped. On day 6, renin further dropped to 136 ng/L, and the patient was hemodynamically stable and discharged from the ICU. In conclusion, ATII favorably affected the patient’s vascular tone, enabling rapid hemodynamic stabilization and shortening the ICU and hospital stay.

Inflammatory Biomarkers Affecting Survival Prognosis in Patients Receiving Veno-Venous ECMO for Severe COVID-19 Pneumonia

Severe COVID-19 pneumonia in which mechanical ventilation is unable to achieve adequate gas exchange can be treated with veno-venous ECMO, eliminating the need for aggressive mechanical ventilation which might promote ventilator-induced lung injury and increase mortality. In this retrospective observational study, 18 critically ill COVID-19 patients who were treated using V-V ECMO during an 11-month period in a tertiary COVID-19 hospital were analyzed. Biomarkers of inflammation and clinical features were compared between survivors and non-survivors. Survival rates were compared between patients receiving ECMO and propensity matched mechanically ventilated controls. There were 7 survivors and 11 non-survivors. The survivors were significantly younger, with a higher proportion of females, higher serum procalcitonin at ICU admission, and before initiation of ECMO they had significantly lower Murray scores, PaCO₂, WBC counts, serum ferritin levels, and higher glomerular filtration rates. No significant difference in mortality was found between patients treated with ECMO compared to patients treated using conventional lung protective ventilation. Hypercapnia, leukocytosis, reduced glomerular filtration rate, and increased serum ferritin levels prior to initiation of V-V ECMO in patients with severe COVID-19 pneumonia may be early warning signs of reduced chance of survival. Further multicentric studies are needed to confirm these findings.