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PurposeAfter trauma and surgery, upper gastrointestinal bleeding (UGIB) is the most common condition that can require massive transfusion (MT). The present study aimed to analyze and compare the prognostic performance of the Glasgow-Blatchford (GB), pre-endoscopy Rockall (PER), and modified early warning (MEW) scores for predicting MT in patients with unstable UGIB.Materials and MethodsThis retrospective observational study included patients with UGIB from March 2016 to February 2018. Receiver operating characteristics analysis was performed to examine the prognostic performance of the GB, PER, and MEW scoring systems. Logistic regression analysis was used to identify independent risk factors for MT, after adjusting for relevant covariates. The primary outcome was MT.ResultsOf the 484 included patients with unstable UGIB, 19 (3.9%) received an MT. The areas under the curves (AUCs) of the GB, PER, and MEW scores for MT were 0.577 [95% confidence interval (CI), 0.531–0.621], 0.570 (95% CI, 0.525–0.615), and 0.767 (95% CI, 0.727–0.804), respectively. The AUC of the MEW score was significantly different from those of the GB and PER scores. In multivariate analysis, MEW score was independently associated with MT in patients with unstable UGIB (odds ratio, 1.495; 95% CI, 1.100–2.033; p=0.010).ConclusionIn unstable UGIB patients, MEW score had the best prognostic performance for MT among three scoring systems.

Pralidoxime is a common antidote for organophosphate poisoning; however, studies have also reported pralidoxime's pressor effect, which may facilitate the restoration of spontaneous circulation (ROSC) after cardiac arrest by improving coronary perfusion pressure (CPP). We investigated the immediate cardiovascular effects of pralidoxime in anaesthetised normal rats and the effects of pralidoxime administration during cardiopulmonary resuscitation (CPR) in a pig model of cardiac arrest. To evaluate the immediate cardiovascular effects of pralidoxime, seven anaesthetised normal rats received saline or pralidoxime (20 mg/kg) in a randomised crossover design, and the responses were determined using the conductance catheter technique. To evaluate the effects of pralidoxime administration during CPR, 22 pigs randomly received either 80 mg/kg of pralidoxime or an equivalent volume of saline during CPR. In the rats, pralidoxime significantly increased arterial pressure than saline (P = .044). The peak effect on arterial pressure was observed in the first minute. In a pig model of cardiac arrest, CPP during CPR was higher in the pralidoxime group than in the control group (P = .002). ROSC was attained in three animals (27.3%) in the control group and nine animals (81.8%) in the pralidoxime group (P = .010). Three animals (27.3%) in the control group and eight animals (72.2%) in the pralidoxime group survived the 6‐hour period (P = .033). In conclusion, pralidoxime had a rapid onset of pressor effect. Pralidoxime administered during CPR led to significantly higher rates of ROSC and 6‐hour survival by improving CPP in a pig model.

Resin transfer molding is a popular process to fabricate polymer composites reinforced with a large amount of glass or carbon fibers. In general, fiber reinforcements are put in a mold, and a liquid resin such as epoxy resin is injected into the mold after preheating. For successful production of polymer composites via a resin transfer molding process, the filling and curing stages of the liquid resin as well as the mold design should be optimized. Recently, polymer composites reinforced with nanoparticles are attracting attention of researchers in academia and industries because efficient reinforcement can be achieved by small loading of nanoparticles such as carbon nanotubes and exfoliated clays. In this work, as an effort to develop light weight automotive parts, graphenes were investigated as a nano size reinforcement of epoxy resin for resin transfer molding. Graphenes were prepared from graphites by microwave irradiation. Addition of graphenes to bisphenol A based epoxy resins such as YD-128 from Kukdo Chemical results in an increase in viscosity and shear thinning behavior, affecting the filling process. The curing of epoxy resins is also affected by graphenes. In order to develop a model for simulation of the filling and curing of epoxy resins containing different amounts of graphenes in the resin transfer molding, FLUENT and MATLAB have been used in this study, which are a finite element based computational fluid dynamics analysis tool and a general purpose numerical analysis tool, respectively. The effects of graphenes on the mold filling pattern and curing profile are discussed for the resin transfer molding of bisphenol A based epoxy resins.