Pooled analysis of WHO Surgical Safety Checklist use and mortality after emergency laparotomy

Background The World Health Organization (WHO) Surgical Safety Checklist has fostered safe practice for 10 years, yet its place in emergency surgery has not been assessed on a global scale. The aim of this study was to evaluate reported checklist use in emergency settings and examine the relationship with perioperative mortality in patients who had emergency laparotomy. Methods In two multinational cohort studies, adults undergoing emergency laparotomy were compared with those having elective gastrointestinal surgery. Relationships between reported checklist use and mortality were determined using multivariable logistic regression and bootstrapped simulation. Results Of 12 296 patients included from 76 countries, 4843 underwent emergency laparotomy. After adjusting for patient and disease factors, checklist use before emergency laparotomy was more common in countries with a high Human Development Index (HDI) (2455 of 2741, 89.6 per cent) compared with that in countries with a middle (753 of 1242, 60.6 per cent; odds ratio (OR) 0.17, 95 per cent c.i. 0.14 to 0.21, P <0001) or low (363 of 860, 422 per cent; OR 008, 007 to 010, P <0.001) HDI. Checklist use was less common in elective surgery than for emergency laparotomy in high-HDI countries (risk difference -94 (95 per cent c.i. -11.9 to -6.9) per cent; P <0001), but the relationship was reversed in low-HDI countries (+121 (+7.0 to +173) per cent; P <0001). In multivariable models, checklist use was associated with a lower 30-day perioperative mortality (OR 0.60, 0.50 to 073; P <0.001). The greatest absolute benefit was seen for emergency surgery in low- and middle-HDI countries. Conclusion Checklist use in emergency laparotomy was associated with a significantly lower perioperative mortality rate. Checklist use in low-HDI countries was half that in high-HDI countries.Peer reviewe

Global variation in anastomosis and end colostomy formation following left-sided colorectal resection

Background End colostomy rates following colorectal resection vary across institutions in high-income settings, being influenced by patient, disease, surgeon and system factors. This study aimed to assess global variation in end colostomy rates after left-sided colorectal resection. Methods This study comprised an analysis of GlobalSurg-1 and -2 international, prospective, observational cohort studies (2014, 2016), including consecutive adult patients undergoing elective or emergency left-sided colorectal resection within discrete 2-week windows. Countries were grouped into high-, middle- and low-income tertiles according to the United Nations Human Development Index (HDI). Factors associated with colostomy formation versus primary anastomosis were explored using a multilevel, multivariable logistic regression model. Results In total, 1635 patients from 242 hospitals in 57 countries undergoing left-sided colorectal resection were included: 113 (6·9 per cent) from low-HDI, 254 (15·5 per cent) from middle-HDI and 1268 (77·6 per cent) from high-HDI countries. There was a higher proportion of patients with perforated disease (57·5, 40·9 and 35·4 per cent; P < 0·001) and subsequent use of end colostomy (52·2, 24·8 and 18·9 per cent; P < 0·001) in low- compared with middle- and high-HDI settings. The association with colostomy use in low-HDI settings persisted (odds ratio (OR) 3·20, 95 per cent c.i. 1·35 to 7·57; P = 0·008) after risk adjustment for malignant disease (OR 2·34, 1·65 to 3·32; P < 0·001), emergency surgery (OR 4·08, 2·73 to 6·10; P < 0·001), time to operation at least 48 h (OR 1·99, 1·28 to 3·09; P = 0·002) and disease perforation (OR 4·00, 2·81 to 5·69; P < 0·001). Conclusion Global differences existed in the proportion of patients receiving end stomas after left-sided colorectal resection based on income, which went beyond case mix alone

PROTOTYPING OF PHOTOCATALYTIC MICROREACTOR AND TESTING OF PHOTODEGRADATION OF ORGANIC DYE

A photocatalytic microreactor is defined as a microfluidic device, which is integrated with a photocatalytic coating of TiO2 deposited on the inner surface of microchannels. This device is capable of degradation of organic dye solution in water in a continuous flow under the action of ultraviolet light. The objectives of this work were to present a rapid and economically viable approach for the prototyping photocatalytic microfluidic devices and to evaluate their photodegradation capability for organic dyes by ultravioletvisible spectrophotometry. Prototyping of polydimethylsiloxane PDMS/TiO2/glass microreactors includes several procedures such as mold preparation, microchannel confection on PDMS surface, deposition of TiO2 on these microchannels, O-2 plasma treatment of PDMS/TiO2 and glass surface for sealing these two parts. The efficiency of the photocatalytic microreactors was evaluated by fluxing two organic dye solutions, rhodamine B and methylene blue, with different flow rates of between 2 and 4 mL h(-1). When the flow rate at 2 mL h(-1) was applied, discoloration of similar to 65% was achieved for both dye solutions, while PDMS/glass microchannels, without TiO2 film, demonstrated much lower discoloration of between 24 and 42% for rhodamine B and methylene blue, respectively. This confirmed that TiO2 was successfully deposited onto PDMS microchannels

The effect of titanate nanotube/Y2W3O12 hybrid fillers on mechanical and thermal properties of HDPE-based composites

Hybrid fillers have triggered significant research in the field of polymer-based composites because they offer a range of properties that cannot be achieved by a single filler. Here a novel hybrid filler comprised of titanate nanotubes (TTNT) and Y2W3O12, a thermomiotic ceramic, was incorporated into a high density polyethylene matrix (HDPE) at an extremely low concentration (2 mass %). The influence of TTNT/Y2W3O12 mass ratio (1:1, 1:2 and 2:1), surface treatment of hybrid filler with cetyltrimethylammonium bromide (CTAB) and chemical modification of HDPE with polyethylene-grafted maleic anhydride (PE-g-MA), on the resulting mechanical and thermal properties of HDPE-based composites was investigated. The largest increase (25%) in Young's modulus and the greatest reduction (23%) in coefficient of thermal expansion (CTE) of HDPE was achieved for 2:1 TTNT/Y2W3O12 mass ratio, without significant alteration of thermal degradation beginning or thermal conductivity of HDPE. At this optimum TTNT/Y2W3O12 mass ratio, CTAB treatment of fillers was more efficient than PE-g-MA modification of matrix promoting a better dispersion of TTNT/Y2W3O12, leading to an increase of 34% in composite stiffness and a CTE reduction of 18%, although both treatments improved hybrid filler-matrix interfaces, as judged by a rise of 6% in yield strength

Lepidocrocite-like ferrititanate nanosheets and their full exfoliation with quaternary ammonium compounds

Efficient methods for the synthesis of layered structure nanomaterials (nanosheets), their complete exfoliation (delamination) into the layers of atomic thickness and design of organic-inorganic nanohybrids present important stages toward development of improved polymer-based nanocomposites and pillared heterostructures with potential application in purification technologies such as photocatalysis. A rapid and efficient exfoliation process of protonated layered ferrititanates with lepidocrocite-like structure and formation of organic-inorganic nanohybrids is performed starting from the nanosheets composed of only a few host layers and nanometric lateral dimensions using quaternary ammonium compounds. These nanosheets are initially synthesized from a highly abundant precursor through an alkaline hydrothermal route. We demonstrated that climethyldioctadecylammonium cations strongly interact with the exfoliated single host layers (075 nm thick) providing thermal stability (-500 "C) to the as-prepared organic-inorganic nanohybrid over the temperature range commonly applied for the processing of thermoplastic nanocomposites. (C) 2015 Elsevier Ltd. All rights reserved

Visible light sensitive mesoporous nanohybrids of lepidocrocite-like ferrititanate coupled to a charge transfer complex: Synthesis, characterization and photocatalytic degradation of NO

The efficiency of photo-oxidation of pollutants catalysed by semiconductors is still limited for real-world applications due to several drawbacks, such as a) insufficient absorption of visible radiation, which predominates in solar spectrum, b) rapid free electron to hole recombination, c) small surface area, built from equilibrium crystallographic facets with low adsorption capacities and d) photo-corrosion. The present study disclosures new mesoporous heterostructures, built from exfoliated lepidocrocite-like ferrititanates and TiO2 (anatase)-acetylacetone charge transfer complex, capable of reducing free electron-to-hole recombination rate through a robust charge separation and sensitive to the visible light spectrum. The synthesis route is based on soft-chemistry and low temperature calcination at 300 °C. Two different partially pillarized heterostructures, denoted as HM-1 and HM-2, have been synthesized. It was observed that the heterostructure HM-1 was four times more active toward photocatalytic degradation of NO gas in comparison to the benchmark photocatalytic material P25. The lower activity of the heterostructure HM-2, comparable to that of P-25, was attributed to the high value of Urbach energy that indicates high number of defect sites within energy band-gap of the constituent semiconductor components. [Ti] anatase/[Ti] ferrititanate mol ratio might also play a role in photocatalytic efficiency