Browsing by Subject "health sciences"

Now showing 1 - 4 of 4
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    A descriptive study of the relationship between preoperative body temperature and intraoperative core temperature change in adults under general anaesthesia
    (2022) Steyn, Francois; Du Toit, Leon; Ross, Hofmeyr
    Background: Despite numerous guidelines on perioperative temperature management, perioperative hypothermia remains common. Prewarming to prevent redistribution hypothermia is supported by evidence, but not widely practiced. We investigate the measurement of preoperative mean body temperature as a potential tool for individualising the practise of prewarming. Methods: We hypothesised that patients who experience intraoperative hypothermia have a lower preoperative mean body temperature. A longitudinal study was conducted in adult patients presenting for ophthalmological surgery under general anaesthesia, to describe the relationship between the incidence of hypothermia within the first hour of anaesthesia and preoperative mean body temperature. Results: Sixty-five patients were enrolled. Twelve participants (18%) presented to the operating theatre hypothermic (core temperature <36.0°C). A further twenty-eight (43%) became hypothermic during the procedure. All hypothermia events occurred within sixty minutes after induction of anaesthesia, and half of the events occurred within nineteen minutes. The difference in preoperative mean body temperature between those with- and without intraoperative hypothermia was only -0.2°C (95% CI -0.4, 0.1). This is neither clinically relevant nor statistically noteworthy. In Cox proportional hazards analysis, BMI and ASA status compounded the observed association between preoperative mean body temperature and the incidence of intraoperative hypothermia. A higher BMI and ASA are associated with a lower incidence of hypothermia. Conclusion: We conclude that intraoperative hypothermia is common and occurs early after induction of anaesthesia. We observed no useful difference in preoperative mean body temperature to help distinguish between patients who become hypothermic and those who do not. Without a useful risk prediction tool, a generic approach to prewarming remains appropriate. Preoperative screening for pre-existing hypothermia should be practiced, even in cases considered as low risk.
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    Advanced internet searching to find Open Educational Resources and Creative Commons
    (2012) Southgate, Nicole
    Open Educational Resources are resources which are accessed freely and can be used for teaching, learning and research. This resource is aimed at teaching second year medical students how to do an advanced search for open educational resources (OER) and images, videos and audio clips with a Creative Commons license. It also provides a list of links to useful online resources.
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    Digital professionalism
    (2012) Mitchell, Veronica; Southgate, Nicole
    The rapid, expansive and evolving use of social media has prompted the need to interrogate its impact for future health professionals. A new initiative teaching first year health science students about their online identity has proven valuable. The importance of communication skills and respect for others through social media is identified and explained.
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    Investigating neuroinflammation in schizophrenia: a proton magnetic resonance spectroscopy (1H-MRS) and cytokine study
    (2022) Burger, Antoinette; Stein, Dan; Howells, Fleur
    Introduction: There are similarities in the phenomenology and psychobiology of schizophrenia and methamphetamine psychosis, with evidence of alterations in glutamatergic function in both conditions, and of involvement of inflammatory pathways in schizophrenia and methamphetamine abuse. Few studies have directly compared glutamatergic and inflammatory metabolites in thalamo-cortical circuitry across schizophrenia and methamphetamine-induced psychosis or assessed the relationship between such metabolites and inflammatory markers in either disorder. This study aimed to 1) compare glutamatergic and neuroinflammatory metabolites in thalamo-cortical circuitry in schizophrenia and methamphetamine-induced psychosis, and 2) to investigate associations between glutamatergic metabolites, neuroinflammatory metabolites, and peripheral cytokine levels in both disorders. Methods: One hundred and sixteen participants were recruited – 44 with schizophrenia, 34 with methamphetamine-induced psychosis, and 38 healthy controls. All participants underwent a magnetic resonance imaging scan, which included magnetic resonance spectroscopy with voxels located in the anterior cingulate cortex (ACC) and left thalamus as well as a chemical-shift imaging 2-dimensional slice. Neurometabolites obtained included glutamatergic metabolites (glutamate (Glu), glutamine (Gln) and glutamate plus glutamine (Glx)) and neuroinflammatory metabolites (myo-inositol (mI), n-acetyl-aspartate (NAA), and n-acetyl aspartate plus n-acetyl-aspartyl glutamate (NAA+NAAG)). Absolute metabolite concentrations are reported. Serum cytokine concentrations were measured. For group differences, parametric data were analysed with one-way analysis of variance and nonparametric data analysed with Kruskal Wallis tests, followed by relevant post-hoc tests. Associations were determined using Spearman's rank-order coefficient. Significant associations were followed by comparison of correlations of independent samples. Results: There were no differences between neurometabolites in schizophrenia and healthy controls. The methamphetamine-induced psychotic disorder group had lower relative nacetyl-aspartate plus n-acetyl-aspartyl glutamate in left dorsolateral prefrontal cortex and left frontal white matter, compared to healthy controls. In schizophrenia, positive associations were found between absolute glutamatergic metabolites and absolute inflammatory metabolites in the anterior cingulate cortex (n-acetyl-aspartate with glutamate, lower n-acetylaspartate with n-acetyl-aspartyl glutamate plus glutamate, myo-inositol with glutamate, myoinositol with glutamate plush glutamine). Several positive relationships were found in mI between different brain areas of the thalamo-cortical circuitry in the methamphetamineinduced psychosis group. Conclusion: In schizophrenia, the associations between lower glutamatergic and lower neuroinflammatory metabolites suggest dysfunction in neuronal tissues in the glutamateglutamine cycle within the thalamo-cortical circuit. In methamphetamine-induced psychosis, lower NAA+NAAG/Cr+PCr in the left dorsolateral prefrontal cortex and left frontal white mattersuggest compromised neuronal integrity associated with chronic disease progression. Furthermore, in this group the associations of mI between brain areas in the thalamo-cortical 6 circuit suggest that neuroinflammatory pathways in this circuit are dysfunctional. Taken together, there may be important differences in the neurobiology of schizophrenia and methamphetamine-induced psychosis.