Is endoanal, introital or transperineal ultrasound diagnosis of sphincter defects more strongly associated with anal incontinence?

INTRODUCTION AND HYPOTHESIS: Our aim was to explore the association between anal incontinence (AI) and persistent anal sphincter defects diagnosed with 3D endoanal (EAUS), introital (IUS) and transperineal ultrasound (TPUS) in women after obstetric anal sphincter injury (OASI) and study the association between sphincter defects and anal pressure. METHODS: We carried out a cross-sectional study of 250 women with OASI recruited during the period 2013-2015. They were examined 6-12 weeks postpartum or in a subsequent pregnancy with 3D EAUS, IUS and TPUS and measurement of anal pressure. Prevalence of urgency/solid/liquid AI or flatal AI and anal pressure were compared in women with a defect and those with an intact sphincter (diagnosed off-line) using Chi-squared and Mann-Whitney U test. RESULTS: At a mean of 23.6 (SD 30.1) months after OASI, more women with defect than those with intact sphincters on EAUS had AI; urgency/solid/liquid AI vs external defect: 36% vs 13% and flatal AI vs internal defect: 27% vs 13%, p < 0.05. On TPUS, more women with defect sphincters had flatal AI: 32% vs 13%, p = 0.03. No difference was found on IUS. Difference between defect and intact sphincters on EAUS, IUS and TPUS respectively was found for mean [SD] maximum anal resting pressure (48 [13] vs 55 [14] mmHg; 48 [12] vs 56 [13] mmHg; 50 [13] vs 54 [14] mmHg) and squeeze incremental pressure (33 [17] vs 49 [28] mmHg; 37 [23] vs 50 [28] mmHg; 36 [18] vs 50 [30] mmHg; p < 0.01). CONCLUSIONS: Endoanal ultrasound had the strongest association with AI symptoms 2 years after OASI. Sphincter defects detected using all ultrasound methods were associated with lower anal pressure

Acceptability and usability of smartphone-based brainwave entrainment technology used by individuals with chronic pain in a home setting

Background: Brainwave entrainment (BWE) using rhythmic visual or auditory stimulation has many potential clinical applications, including the management of chronic pain, where there is a pressing need for novel, safe and effective treatments. The aim of this study was to gain qualitative feedback on the acceptability and usability of a novel BWE smartphone application, to ensure it meets the needs and wishes of end users. Methods: Fifteen participants with chronic pain used the application at home for 4 weeks. Semi-structured telephone interviews were then carried out. A template analysis approach was used to interpret the findings, with an initial coding template structured around the constructs of a theoretical framework for assessing acceptability of healthcare interventions. Structured data analysis generated a final modified coding structure, capturing themes generated across participants’ accounts. Results: The four main themes were ‘approach to trying out the app: affective attitude and ethicality’, ‘perceived effectiveness’, ‘opportunity costs and burden’ and ‘intervention coherence and self-efficacy’. All participants were willing to engage with the technology and welcomed it as an alternative approach to medications. Participants appreciated the simplicity of design and the ability to choose between visual or auditory stimulation. All the participants felt confident in using the application. Conclusion: The findings demonstrate preliminary support for the acceptability and usability of the BWE application. This is the first qualitative study of BWE to systematically assess these issues

Dynamic thermodynamics with internal energy, volume, and amount of moles as states: Application to liquefied gas tank

Dynamic models for process design, optimization, and control usually solve a set of heat and/or mass balances as a function of time and/or position in the process. To obtain more robust dynamic models and to minimize the amount of assumptions, internal energy, volume, and amount of moles are chosen as states for the conservation laws of the dynamic model. Temperature, pressure, and the amount and composition of the phases are calculated on the basis of these states at every time step. The Redlich-Kwong and Peng-Robinson (RK-PR) cubic equation of state is used as the thermodynamic model. This study describes the aspects of this approach and additionally gives a wide view over the whole internal energy and volume surface in specific phase diagrams. A complete separation between the dynamic balance model and the thermodynamic model is achieved. Several examples show the application of this approach for a liquefied gas tank and demonstrate that the method is applicable to one and two phases in a wide temperature and pressure range, from liquid and/or gas phase to supercritical conditions. © 2009 American Chemical Society.