The biomechanical efficacy of a dressing with a soft cellulose fluff core in protecting prone surgical patients from chest injuries on the operating table

A Polyelectrolyte Colloidal Brush Based on Cellulose: Perspectives for Future Applications

This feature article is devoted to the evaluation of different techniques for producing colloidal polyelectrolyte brushes (CPEBs) based on cellulose nanofibers modified with grafted polyacrylates. The paper also reviews the potential applications of these CPEBs in designing electrode materials and as reinforcing additives. Additionally, we discuss our own perspectives on investigating composites with CPEBs. Herein, polyacrylic acid (PAA) was grafted onto the surface of cellulose nanofibers (CNFs) employing a "grafting from" approach. The effect of the PAA shell on the morphological structure of a composite with polypyrrole (PPy) was investigated. The performance of as-obtained CNF-PAA/PPy as organic electrode material for supercapacitors was examined. Furthermore, this research highlights the ability of CNF-PAA filler to act as an additional crosslinker forming a physical sub-network due to the hydrogen bond interaction inside chemically crosslinked polyacrylamide (PAAm) hydrogels. The enhancement of the mechanical properties of the material with a concomitant decrease in its swelling ratio compared to a pristine PAAm hydrogel was observed. The findings were compared with the recent theoretical foundation pertaining to other similar materials.

An anatomically-realistic computational framework for evaluating the efficacy of protective plates in mitigating non-penetrating ballistic impacts

BACKGROUND

A major threat in combat scenarios is the 'behind armor blunt trauma' (BABT) of a non-penetrating ballistic impact with a ballistic protective plate (BPP). This impact results in pressure waves that propagate through tissues, potentially causing life-threatening damage. To date, there is no standardized procedure for rapid virtual testing of the effectiveness of BPP designs. The objective of this study was to develop a novel, anatomically-accurate, finite element modeling framework, as a decision-making tool to evaluate and rate the biomechanical efficacy of BPPs in protecting the torso from battlefield-acquired non-penetrating impacts.

METHODS

To simulate a blunt impact with a BPP, two types of BPPs representing generic designs of threat-level III and IV plates, and a generic 5.56 mm bullet were modeled, based on their real dimensions, physical and mechanical characteristics (plate level-III is smaller, thinner, and lighter than plate level-IV). The model was validated by phantom testing.

RESULTS

Plate level-IV induced greater strains and stresses in the superficial tissues post the ballistic impact, due to the fact that it is larger, thicker and heavier than plate level-III; the shock wave which is transferred to the superficial tissues behind the BPP is greater in the case of a non-penetrating impact. For example - the area under volumetric tissue exposure histograms of strains and stresses for the skin and adipose tissues were 16.6-19.2% and 17.3-20.3% greater in the case of plate level-IV, for strains and stresses, respectively. The validation demonstrates a strong agreement between the physical phantom experiment and the simulation, with only a 6.37% difference between them.

CONCLUSIONS

Our modelling provides a versatile, powerful testing framework for both industry and clients of BPPs at the prototype design phase, or for quantitative standardized evaluations of candidate products in purchasing decisions and bids.

The incidence of intraoperatively acquired pressure injuries in the park-bench position was reduced by applying soft silicone multilayer foam dressings

The Park-Bench Position (PBP) is associated with a high incidence rate of intraoperatively acquired pressure injuries (IAPIs). Preventive measures must be established to prevent the development of IAPIs. We investigated the risk factors for PBP by applying a soft silicone multilayered foam dressing (SMD) under core temperature management to prevent IAPIs. We conducted a prospective, single-centre, open-label observational study of patients undergoing elective neurosurgery operations using PBP in a university hospital in Japan. The incidence rate of IAPIs in this study was compared with that in our two previous studies, in which a film dressing was applied and core temperature management was not performed. IAPIs developed in 90 patients (6.7%); in the lateral thoracic region in five patients and the iliac crest region in one patient. The operative time (every 1 h: p = 0.0001, OR: odds ratio 3.62, 95% CI: confidence interval 1.73-11.42) was significantly associated with the incidence of IAPIs. In our two previous studies, the incidence rate of IAPIs was 11.0% and 24.1%, respectively, when film dressing was used. SMD may weaken the involvement of risk factors in IAPIs.