39 research outputs found
COVID-19 infection is a significant risk factor for death in patients presenting with acute cholecystitis: a secondary analysis of the ChoCO-W cohort study
Background: During the coronavirus disease (COVID-19) pandemic, there has been a surge in cases of acute cholecystitis. The ChoCO-W global prospective study reported a higher incidence of gangrenous cholecystitis and adverse outcomes in COVID-19 patients. Through this secondary analysis of the ChoCO-W study data, we aim to identify significant risk factors for mortality in patients with acute cholecystitis during the COVID-19 pandemic, emphasizing the role of COVID-19 infection in patient outcomes and treatment efficacy.” Methods: The ChoCO-W global prospective study reported data from 2546 patients collected at 218 centers from 42 countries admitted with acute cholecystitis during the COVID-19 pandemic, from October 1, 2020, to October 31, 2021. Sixty-four of them died. Nonparametric statistical univariate analysis was performed to compare patients who died and patients who survived. Significant factors were then entered into a logistic regression model to define factors predicting mortality. Results: The significant independent factors that predicted death in the logistic regression model with were COVID-19 infection (p < 0.001), postoperative complications (p < 0.001), and type (open/laparoscopic) of surgical intervention (p = 0.003). The odds of death increased 5 times with the COVID-19 infection, 6 times in the presence of complications, and it was reduced by 86% with adequate source control. Survivors predominantly underwent urgent laparoscopic cholecystectomy (52.3% vs. 23.4%). Conclusions: COVID-19 was an independent risk factor for death in patients with acute cholecystitis. Early laparoscopic cholecystectomy has emerged as the cornerstone of treatment for hemodynamically stable patients
Goodbye Hartmann trial: a prospective, international, multicenter, observational study on the current use of a surgical procedure developed a century ago
Background: Literature suggests colonic resection and primary anastomosis (RPA) instead of Hartmann's procedure (HP) for the treatment of left-sided colonic emergencies. We aim to evaluate the surgical options globally used to treat patients with acute left-sided colonic emergencies and the factors that leading to the choice of treatment, comparing HP and RPA. Methods: This is a prospective, international, multicenter, observational study registered on ClinicalTrials.gov. A total 1215 patients with left-sided colonic emergencies who required surgery were included from 204 centers during the period of March 1, 2020, to May 31, 2020. with a 1-year follow-up. Results: 564 patients (43.1%) were females. The mean age was 65.9 ± 15.6 years. HP was performed in 697 (57.3%) patients and RPA in 384 (31.6%) cases. Complicated acute diverticulitis was the most common cause of left-sided colonic emergencies (40.2%), followed by colorectal malignancy (36.6%). Severe complications (Clavien-Dindo ≥ 3b) were higher in the HP group (P < 0.001). 30-day mortality was higher in HP patients (13.7%), especially in case of bowel perforation and diffused peritonitis. 1-year follow-up showed no differences on ostomy reversal rate between HP and RPA. (P = 0.127). A backward likelihood logistic regression model showed that RPA was preferred in younger patients, having low ASA score (≤ 3), in case of large bowel obstruction, absence of colonic ischemia, longer time from admission to surgery, operating early at the day working hours, by a surgeon who performed more than 50 colorectal resections. Conclusions: After 100 years since the first Hartmann's procedure, HP remains the most common treatment for left-sided colorectal emergencies. Treatment's choice depends on patient characteristics, the time of surgery and the experience of the surgeon. RPA should be considered as the gold standard for surgery, with HP being an exception
Recovery of energy and chemicals from carbonaceous materials
Biomass is the most common form of carbonaceous materials, widely used in the third world. In this study, methods of recovery of organic wastes are evaluated. These methods are mainly hydrogenation, pyrolysis, thermal and/or catalytic cracking, gasification and bioconversion. These methods are compared with each other. During these processes, the polymeric structure is broken down, producing smaller intermediate species, which can further react and produce a mixture of smaller hydrocarbon molecules, liquids and gases. These hydrocarbons could be used as fuel or as chemical raw materials for several industries. Thus, plastic wastes are recovered by using alternative energy sources
Biorefineries for biofuel upgrading: A critical review
This study reviews the biofuel valorization facilities as well as the future importance of biorefineries. Biomass can be converted into useful biofuels and bio-chemicals via biomass upgrading and biorefinery technologies. A biorefinery is a facility that integrates biomass conversion processes to produce fuels, power, and chemicals from biomass. Biomass upgrading processes include fractionation, liquefaction, pyrolysis, hydrolysis, fermentation, and gasification. Upgraded bio-oil from biomass pyrolysis can be used in vehicle engines as fuel. The benefits of an integrated biorefinery are numerous because of the diversification in feedstocks and products. There are currently several different levels of integration in biorefineries which adds to their sustainability, both economically and environmentally. Economic and production advantages increase with the level of integration in the biorefinery.Biomass Biofuel Fractionation Upgrading Biorefining
Importance of algae oil as a source of biodiesel
Algae are the fastest-growing plants in the world. Industrial reactors for algal culture are open ponds, photobioreactors and closed systems. Algae are very important as a biomass source. Algae will some day be competitive as a source for biofuel. Different species of algae may be better suited for different types of fuel. Algae can be grown almost anywhere, even on sewage or salt water, and does not require fertile land or food crops, and processing requires less energy than the algae provides. Algae can be a replacement for oil based fuels, one that is more effective and has no disadvantages. Algae are among the fastest-growing plants in the world, and about 50% of their weight is oil. This lipid oil can be used to make biodiesel for cars, trucks, and airplanes. Microalgae have much faster growth-rates than terrestrial crops. the per unit area yield of oil from algae is estimated to be from 20,000 to 80,0001 per acre, per year; this is 7-31 times greater than the next best crop, palm oil. The lipid and fatty acid contents of microalgae vary in accordance with culture conditions. Most current research on oil extraction is focused on microalgae to produce biodiesel from algal oil. Algal-oil processes into biodiesel as easily as oil derived from land-based crops. (C) 2010 Elsevier Ltd. All rights reserved
Biomass pyrolysis for liquid fuels and chemicals: A review
797-804Biomass pyrolysis produces fuels and chemicals. Pyrolysis (conventional, fast and flash) can produce solid (charcoal),
liquid (tar and other organics), and gaseous products (H₂, CO₂, CO) between 625 and 775 K. Charcoal yield decreases as
temperature increases. Production of liquid products is maximum between 625-725 K
