Survival prediction of trauma patients: a study on US National Trauma Data Bank

Background

Exceptional circumstances like major incidents or natural disasters may cause a huge number of victims that might not be immediately and simultaneously saved. In these cases it is important to define priorities avoiding to waste time and resources for not savable victims. Trauma and Injury Severity Score (TRISS) methodology is the well-known and standard system usually used by practitioners to predict the survival probability of trauma patients. However, practitioners have noted that the accuracy of TRISS predictions is unacceptable especially for severely injured patients. Thus, alternative methods should be proposed.

Methods

In this work we evaluate different approaches for predicting whether a patient will survive or not according to simple and easily measurable observations. We conducted a rigorous, comparative study based on the most important prediction techniques using real clinical data of the US National Trauma Data Bank.

Results

Empirical results show that well-known Machine Learning classifiers can outperform the TRISS methodology. Based on our findings, we can say that the best approach we evaluated is Random Forest: it has the best accuracy, the best area under the curve, and k-statistic, as well as the second-best sensitivity and specificity. It has also a good calibration curve. Furthermore, its performance monotonically increases as the dataset size grows, meaning that it can be very effective to exploit incoming knowledge. Considering the whole dataset, it is always better than TRISS. Finally, we implemented a new tool to compute the survival of victims. This will help medical practitioners to obtain a better accuracy than the TRISS tools.

Conclusion

Random Forests may be a good candidate solution for improving the predictions on survival upon the standard TRISS methodology.

     

自体血清滴眼液对屈光性角膜切削术后角膜上皮愈合的影响

目的：研究自体血清滴眼液对屈光性角膜切削术(PRK)后角膜上皮愈合的影响。

方法：本研究共纳入20例40眼近视及近视散光患者,其中男性9例,女性11例。每例患者随机选取一眼作为研究组应用20%含自体血清的人工泪液,另一眼为对照组应用常规人工泪液。PRK 术中,40眼均于角膜表面居中放置直径8 mm的酒精储槽, 20%的酒精作用20s。术后每天观察直到角膜上皮愈合后,分别于1mo,6mo,12mo进行随访。上皮愈合时间为主要观察指标,并记录裸眼视力(UCVA),显然验光和混浊度。

结果：两组间术前小瞳检影结果无明显差异。术后1d,2d,3d,研究组平均疼痛评分均显著低于对照组(P<0.05)。术后1d,3d,研究组的平均水平和垂直上皮缺损低于对照组(P<0.05)。研究组上皮完全愈合的平均时间比对照组短约0.7d(3.15±0.366d vs 3.85±0.587d, P=0.00)。

结论：研究表明,应用自体血清滴眼液,通过加速角膜上皮愈合和减轻疼痛,从而缩短视力恢复时间,降低屈光性角膜切削术术后不适、混浊度和感染风险。     

The comparison of total capacity antioxidant in the serum of people with pterygium and control subjects

AIM: To evaluate the effects of genipin cross-linking on bullous keratopathy in rabbits. METHODS: Nine female New Zealand white rabbits with bullous keratopathy were used as an experimental model. They were randomized into three groups. Corneas in Group A (treatment group, n=3) were immersed in 0.25% genipin at 24℃ for 40min; those in Group B (control group, n=3) were immersed in 0.9% sodium chloride solution at 24℃ for 40min; and those in Group C (blank control group, n=3) received no treatment. Follow-up examinations were performed within 2wk after treatment, including slit-lamp microscopy, central corneal thickness (CCT), evaluations of body weight and stress responses, histopathological analyses, and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) for detecting stromal cell apoptosis. RESULTS: Compared to Groups B and C, remission of corneal edema, corneal healing, disappearance of epithelial bullae, a significant decrease in CCT (P<0.05), and a significant increase in body weight (P<0.05) were found in Group A. Animals in Group A became more active and showed less aggression and violent resistance behavior. More regular and dense arrangement of collagen fibers in the corneal stroma and formation of blue strips of cross-linking products were observed in Group A. Cell apoptosis occasionally occurred in the corneal stroma of Group A, while no cell apoptosis was observed in Groups B and C. CONCLUSION: Genipin cross-linking treatment for bullous keratopathy in rabbits results in remission of corneal edema and relief of pain. We hypothesize that genipin cross-linking strengthens collagen fibers in corneal stroma to avoid the formation of corneal edema and bullae.     

A preliminary study of neuroSPECT evaluation of patients with post-traumatic smell impairment

Background

Attenuation correction is generally used to PET images to achieve count rate values independent from tissue densities. The goal of this study was to provide a qualitative comparison of attenuation corrected PET images produced by a PET-CT device (CT, 120 kV, 40 mAs, FOV 600 mm) with and without segmentation of transmission data (ACseg⁺ and ACseg^-respectively). Methods: The reconstructed images were compared to attenuation corrected images obtained with a high-energy transmission source (Cs-137 – 662 keV). Thirty oncologic patients were studied using CT and ¹³⁷Cs for attenuation correction. All image data were acquired using the Gemini PET-CT scanner (Philips Medical Systems). It is an open PET-CT system that consists of the MX8000 multislice CT and the Allegro PET scanner arranged in a separable configuration. Images with ACseg⁺ and ACseg^- were analyzed simultaneously in coronal, sagittal and transaxial planes. Two nuclear medicine physicians reviewed the image sets. Results: The image quality in the area of metal implants was better with ACseg⁺ than ACseg^-, without metal induced artifacts generally observed in CT corrected images. Further the images with ACseg⁺ were qualitatively comparable to those obtained with ¹³⁷Cs attenuation correction. Conclusions: In case of metal implants, PET studies corrected by CT should preferably use the ACseg⁺ method to avoid the image artifacts.     

Novel <Emphasis Type="Italic">UBR1</Emphasis> gene mutation in a patient with typical phenotype of Johanson–Blizzard syndrome

Johanson–Blizzard syndrome is a rare autosomal recessive disorder, characterized by exocrine pancreatic deficiency and a wide range of other abnormalities. We present here an infant with failure to thrive, exocrine pancreatic deficiency, short stature and developmental delay, cutis aplasia on the scalp, aplasia of alae nasi, hypospadias, hypothyroidism, myxomatous mitral valve, and patent ductus arteriosus. Molecular studies revealed a novel homozygous nonsense mutation in exon 38 of the UBR1 gene, which confirmed the diagnosis of Johanson–Blizzard syndrome. It should be acknowledged that the combination of exocrine pancreatic insufficiency and nasal wing hypo-aplasia is pathognomonic for this syndrome. Prompt diagnosis and exact monitoring of the patients with JBS are required to avoid further complications.     

Short-Term Result of Ductus Arteriosus Stent Implantation Compared With Surgically Created Shunts

This report aims to compare the researchers?? early experience with the safety, efficacy, short-term outcomes, and complications of patent ductus arteriosus (PDA) stents in neonates having duct-dependent pulmonary circulation with those of surgically created shunts. Between April 2009 and April 2011, 18 infants with duct-dependent pulmonary circulation underwent cardiac catheterization for PDA stenting as the first palliative procedure in a referral center. For comparison, 20 infants who underwent surgical aortopulmonary shunt placement in another center were used. Follow-up assessment included clinical examination, echocardiography, oxygen saturation, and cardiac catheterization studies. Access and stenting for the PDA were successful in 15 patients (83.3?%). The mean procedure time was 58.43?±?41.25?min, and the mean fluoroscopy time was 18.81?±?5.64?min. Three patients (20?%) in the stented group and 6 patients (30?%) in the surgical group died (P?=?0.09). After a 6-month follow-up period, none of the patients had significant stent stenosis requiring reintervention. The oxygen saturation increase did not differ significantly between the two groups either immediately after the procedure or 6?months later (P?>?0.5). The left pulmonary artery diameter, McGoon ratio, and Nakata index did not differ significantly between the two groups (P?>?0.05), but the right pulmonary diameter was larger in the stented group (5.01?±?0.45 vs 4.1?±?0.49?mm; P?=?0.0001). Stenting for the PDA is an appropriate alternative to surgical shunt creation in many patients with duct-dependent circulation. In our sample, the two groups did not differ significantly in terms of outcome or mortality.     

Anti-CD38 autoimmunity in patients with chronic autoimmune thyroiditis or Graves' disease.

Autoantibodies directed against human CD38 (an enzyme catalysing the interconversion of NAD(+) and cyclic ADP-ribose) have been demonstrated recently in patients with type 2 diabetes. We tested 220 consecutive Caucasian patients with autoimmune chronic thyroiditis, 104 patients with Graves' disease, 220 subjects from the general population (control I) and 78 healthy control subjects not affected by thyroid autoimmune disorders (control II) for the presence of anti-CD38 autoimmunity. Using Western blot analysis and optical densitometry, a specific band corresponding to human recombinant CD38 was identified in the serum of several subjects. By defining anti-CD38 positivity as a standardized optical reading > 3 s.d. higher than the mean value of control I, 10.4% of patients with thyroiditis and 7.7% of Graves' patients were anti-CD38 positive (P = 0.0009 versus 1.8% of control I). Similarly, 13.1% of patients with thyroiditis and 10.5% of Graves' patients had a standardized optical reading > 3 s.d. higher than the mean value of the subjects not affected by thyroid autoimmune disorders (P = 0.002 versus 1.2% of control II). Anti-CD38 autoimmunity did not differ between euthyroid, hyperthyroid or hypothyroid patients or between patients with or without thyroid hypoechogenicity. Anti-CD38 autoantibodies were associated with higher levels of circulating antithyroid-peroxidase antibodies (P = 0.03) and they were more frequent in Graves' patients with ophthalmopathy (P < 0.05). Anti-CD38 autoantibodies are a new autoimmune marker in chronic autoimmune thyroiditis and Graves' disease. The specific role of CD38 and its autoantibodies in the modulation of thyroid cell function or growth remains to be investigated.     

Nonreducible rotational head tilt and lateral mass collapse. a prospective study of frequency,radiographic findings,and clinical features in patients with rheumatoid arthritis

Of 126 hospitalized, but otherwise unselected, patients with rheumatoid arthritis, 12 (10%) had a persisting nonreducible rotational head tilt deformity (NRRHT). These 12 were grouped with an additional 12 similar subjects, previously found to have the same condition, and all 24 were compared with the remaining 114 who did not have head tilt. Patients with NRRHT differed significantly from the others in that the former were more likely to have a destructive peripheral arthritis, headache, limited neck motion, and various cervical subluxations. All 24 subjects with NRRHT had predominately unilateral collapse of the lateral masses of the atlas and/or axis, compared with only 2 of the 114 with normal head position. The head always tilted to the side of the lateral mass collapse, which appeared to be the sole or major cause of the abnormal head position.     

Preparation and Characterization of Novel Microgels Containing Nano-SiO2 and Copolymeric Hydrogel Based on Poly (Acrylamide) and Poly (Acrylic Acid): Morphological,Structural and Swelling Studies

In this paper, novel microgels containing nano-SiO₂ were prepared by in situ copolymerization using nano-SiO₂ particles as a reinforcing agent, nanosilica functional monomer (silane-modified nano-SiO₂) as a structure and morphology director, acrylamide (AAm) as a monomer, acrylic acid (AAc) as a comonomer, potassium persulfate (KPS) as a polymerization initiator, and N,N′-methylene bis (acrylamide) (MBA) as a crosslinker. In addition, a conventional copolymeric hydrogel based on poly (acrylamide/acrylic acid) was synthesized by solution polymerization. The microgel samples, hydrogel and nanoparticles were characterized by transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM), Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). A FESEM micrograph of copolymeric hydrogel showed the high porosity and 3D interconnected microstructure. Furthermore, FESEM results demonstrated that when nano-SiO₂ particles were used in the AAm/AAc copolymerization process, the microstructure and morphology of product changed from porous hydrogel to a nanocomposite microgel with cauliflower-like morphology. According to FESEM images, the copolymerization of AAm and AAc monomers with a nanosilica functional monomer or polymerizable nanosilica particle as a seed led to a microgel with core–shell structure and morphology. These results demonstrated that the polymerizable vinyl group on nano-SiO₂ particles have controlled the copolymerization and the product morphology. FTIR analysis showed that the copolymeric chains of polyacrylamide (PAAm) and poly (acrylic acid) (PAAc) were chemically bonded to the surfaces of the nano-SiO₂ particles and silane-modified nano-SiO₂. The particulate character of microgel samples and the existence of long distance among aggregations of particles led to rapid swelling and increasing of porosity and therefore increasing of degree of swelling.