Oxygen systems and quality of care for children with pneumonia, malaria and diarrhoea: Analysis of a stepped-wedge trial in Nigeria

Objectives To evaluate the effect of improved hospital oxygen systems on quality of care (QOC) for children with severe pneumonia, severe malaria, and diarrhoea with severe dehydration. Design Stepped-wedge cluster randomised trial (unblinded), randomised at hospital-level. Setting 12 hospitals in south-west Nigeria. Participants 7,141 children (aged 28 days to 14 years) admitted with severe pneumonia, severe malaria or diarrhoea with severe dehydration between January 2014 and October 2017. Interventions Phase 1 (pulse oximetry) introduced pulse oximetry for all admitted children. Phase 2 (full oxygen system) (i) standardised oxygen equipment package, (ii) clinical education and support, (iii) technical training and support, and (iv) infrastructure and systems support. Outcome measures We used quantitative QOC scores evaluating assessment, diagnosis, treatment, and monitoring practices against World Health Organization and Nigerian standards. We evaluated mean differences in QOC scores between study periods (baseline, oximetry, full oxygen system), using mixed-effects linear regression. Results 7,141 eligible participants; 6,893 (96.5%) had adequate data for analysis. Mean paediatric QOC score (maximum 6) increased from 1.64 to 3.00 (adjusted mean difference 1.39; 95% CI 1.08–1.69, p<0.001) for severe pneumonia and 2.81 to 4.04 (aMD 1.53; 95% CI 1.23–1.83, p<0.001) for severe malaria, comparing the full intervention to baseline, but did not change for diarrhoea with severe dehydration (aMD -0.12; 95% CI -0.46–0.23, p = 0.501). After excluding practices directly related to pulse oximetry and oxygen, we found aMD 0.23 for severe pneumonia (95% CI -0.02–0.48, p = 0.072) and 0.65 for severe malaria (95% CI 0.41–0.89, p<0.001) comparing full intervention to baseline. Sub-analysis showed some improvements (and no deterioration) in care processes not directly related to oxygen or pulse oximetry. Conclusion Improvements in hospital oxygen systems were associated with higher QOC scores, attributable to better use of pulse oximetry and oxygen as well as broader improvements in clinical care, with no negative distortions in care practices. Trial registration ACTRN12617000341325

Synthesis of grafted polybutyl acrylate copolymer on fish collagen

Increasingly, scientists are turning to the study of marine, or fish, collagen, which is increasingly replacing collagen of terrestrial animals, due to the fact that it is hypoallergenic, since it is 96% identical to human protein. Materials based on fish collagen have a number of advantages over their analogue of animal origin: it is not a carrier of infectious diseases of animals transmitted to humans, it has a greater structural similarity to human collagen, which provides a higher level of biocompatibility. Materials based on collagen copolymers with synthetic monomers are promising. The use of hybrid materials also helps to reduce the consumption of non-renewable natural resources. Synthesis of grafted collagen copolymers with polybutyl acrylate was carried out at azobisisobutyronitrile initiation and triethyl borane – oxygen system initiation under comparable conditions under intensive stirring of aqueous solution dispersion of collagen and butyl acrylate. After the synthesis, the aqueous and organic phases of the reaction mixture were analyzed by composition and molecular weight parameters using infrared spectroscopy and size-exclusion chromatography. Changes indicating the formation of a copolymer are observed in the copolymer isolated from the aqueous phase, more pronounced in the triethyl borane – oxygen system. It is assumed that the formation of copolymer macromolecules for azobisisobutyronitrile and organoelement initiator takes place according to different schemes. Schemes for the formation of copolymer macromolecules for AIBN and an organoelement initiator are proposed. Only polybutyl acrylate is present in the organic phase. Biological studies were carried out for fungal resistance and bactericidal activity of the obtained copolymers.

Design performance requirements and failure analysis of oxygen system on civil aircraft

As an important system for maintaining the respiration and safety of people on board, the oxygen system is widely used in modern civil aircraft. This paper provides a complete overview of the system design performance requirements, starting from the basic design theory of the civil aircraft oxygen system. It also analyzes the failure causes of the oxygen system from the perspective of test flight and operation, and provides some references for the analysis of the failure of the civil aircraft oxygen system and the debugging methods.