The pathophysiology of fluid and electrolyte balance in the older adult surgical patient

Background & aims: Age-related physiological changes predispose even the healthy older adult to fluid and electrolyte abnormalities which can cause morbidity and mortality. The aim of this narrative review is to highlight key aspects of age-related pathophysiological changes that affect fluid and electrolyte balance in older adults and underpin their importance in the perioperative period. Methods: The Web of Science, MEDLINE, PubMed and Google Scholar databases were searched using key terms for relevant studies published in English on fluid balance in older adults during the 15 years preceding June 2013. Randomised controlled trials and large cohort studies were sought; other studieswere used when these were not available. The bibliographies of extracted papers were also searched for relevant articles. Results: Older adults are susceptible to dehydration and electrolyte abnormalities, with causes ranging from physical disability restricting access to fluid intake to iatrogenic causes including polypharmacy and unmonitored diuretic usage. Renal senescence, as well as physical and mental decline, increase this susceptibility. Older adults are also predisposed to water retention and related electrolyte abnormalities, exacerbated at times of physiological stress. Positive fluid balance has been shown to be an independent risk factor for morbidity and mortality in critically ill patients with acute kidney injury. Conclusions: Age-related pathophysiological changes in the handling of fluid and electrolytes make older adults undergoing surgery a high-risk group and an understanding of these changes will enable better management of fluid and electrolyte therapy in the older adult

Low urine pH and acid excretion do not predict bone fractures or the loss of bone mineral density: a prospective cohort study

<p>Abstract</p> <p>Background</p> <p>The acid-ash hypothesis, the alkaline diet, and related products are marketed to the general public. Websites, lay literature, and direct mail marketing encourage people to measure their urine pH to assess their health status and their risk of osteoporosis.</p> <p>The objectives of this study were to determine whether 1) low urine pH, or 2) acid excretion in urine [sulfate + chloride + 1.8x phosphate + organic acids] minus [sodium + potassium + 2x calcium + 2x magnesium mEq] in fasting morning urine predict: a) fragility fractures; and b) five-year change of bone mineral density (BMD) in adults.</p> <p>Methods</p> <p>Design: Cohort study: the prospective population-based Canadian Multicentre Osteoporosis Study. Multiple logistic regression was used to examine associations between acid excretion (urine pH and urine acid excretion) in fasting morning with the incidence of fractures (6804 person years). Multiple linear regression was used to examine associations between acid excretion with changes in BMD over 5-years at three sites: lumbar spine, femoral neck, and total hip (n = 651). Potential confounders controlled included: age, gender, family history of osteoporosis, physical activity, smoking, calcium intake, vitamin D status, estrogen status, medications, renal function, urine creatinine, body mass index, and change of body mass index.</p> <p>Results</p> <p>There were no associations between either urine pH or acid excretion and either the incidence of fractures or change of BMD after adjustment for confounders.</p> <p>Conclusion</p> <p>Urine pH and urine acid excretion do not predict osteoporosis risk.</p

Schulische Netzwerke als Professionalisierungsstrategie. Erfahrungen und Forschungsbefunde aus dem Projekt „Schulen im Team“.

Berkemeyer N, Järvinen H, Otto J. Schulische Netzwerke als Professionalisierungsstrategie. Erfahrungen und Forschungsbefunde aus dem Projekt „Schulen im Team“. In: Kobarg M, Fischer C, Dalehefte M, Trepke F, Menk M, eds. Lehrerprofessionalisierung wissenschaftlich begleiten. Strategien und Methoden. Münster: Waxmann; 2012: 117-130

Stärkung der Bildungsqualität durch Regionalisierung?

Otto J, Sendzik N, Berkemeyer N, Manitius V. Stärkung der Bildungsqualität durch Regionalisierung? In: Ratermann M, Stöbe-Blossey S, eds. Governance von Schul- und Elementarbildung. Vergleichende Betrachtungen und Ansätze der Vernetzung. Wiesbaden: VS Verlag für Sozialwissenschaften; 2012: 193-211

Highly Dispersive Optical Soliton Perturbation, with Maximum Intensity, for the Complex Ginzburg–Landau Equation by Semi-Inverse Variation

This work analytically recovers the highly dispersive bright 1–soliton solution using for the perturbed complex Ginzburg–Landau equation, which is studied with three forms of nonlinear refractive index structures. They are Kerr law, parabolic law, and polynomial law. The perturbation terms appear with maximum allowable intensity, also known as full nonlinearity. The semi-inverse variational principle makes this retrieval possible. The amplitude–width relation is obtained by solving a cubic polynomial equation using Cardano’s approach. The parameter constraints for the existence of such solitons are also enumerated

Das Regionale Bildungsbüro als Boundary-Spanner? Eine Betrachtung des kommunalen Managements interschulischer Netzwerke.

Sendzik N, Otto J, Berkemeyer N, Bos W. Das Regionale Bildungsbüro als Boundary-Spanner? Eine Betrachtung des kommunalen Managements interschulischer Netzwerke. In: Hornberg S, Parreira do Amaral M, eds. Deregulierung im Bildungswesen. Münster: Waxmann; 2012: 331-350