The predictive role of serum magnesium in prognosis of critically ill medical patients

Introduction: Magnesium deficiency is a common disorder, but easily ignored as compared to other electrolyte abnormalities. Other studies are showing varied prevalence and increased association with morbidity and mortality. Aims & Objectives: The aim of our study is to find out the prevalence of hypomagnesemia among the critically ill medical patients and to correlate the serum magnesium levels with the mortality and morbidity outcome considering the length of ICU stay, duration of ventilatory support, APACHE 2 score, SOFA score, primary medical conditions in critically ill patients in medical ICU. Methodology: This prospective observational study was conducted in Medical intensive care unit of a tertiary care hospital. After the approval from Institutional ethical committee patients admitted to the medical intensive care unit with age more than 12 years and admitted for more than 2 days were included in the study after obtaining written informed consent. Laboratory tests and radiological investigations were done. APACHE 2(acute physiology and chronic health evaluation) score, SOFA score, total ICU stay, hospital stay, need of mechanical ventilation, duration of ventilatory assistance and associated medical conditions like diabetes, sepsis and electrolyte abnormalities were followed up to assess the relation with mortality and morbidity. Results: Among total of 170 critically ill medical patients were included in the study, prevalence of hypomagnesemia was 56.8 %. The morbidity was higher in hypomagnesaemic patients (48.5% vs 23.4%), longer ICU stay (6.96 ± 3.85 vs 5.12 ± 1.31) and need of mechanical ventilation was also more (68.9% vs 40.4 % p value < 0.003). Sepsis and maximum SOFA score indicate being the predominant underlying factor for hypomagnesemia. Even though association was there between mortality and hypomagnesemia, mortality has not correlated significantly [beta -0.041, t -0.473, 95 % CI -0.219 and 0.138]. Conclusion: Hypomagnesemia is more prevalent among the critically ill medical patients. Hypomagnesemia was also associated with increased mortality, longer ICU stay, higher APACHE 2 score, SOFA score, frequent ventilatory support and significant electrolyte abnormalities also

Stress, genotype and norepinephrine in the prediction of mouse behavior using reinforcement learning

Individual behavioral performance during learning is known to be affected by modulatory factors, such as stress and motivation, and by genetic predispositions that influence sensitivity to these factors. Despite numerous studies, no integrative framework is available that could predict how a given animal would perform a certain learning task in a realistic situation. We found that a simple reinforcement learning model can predict mouse behavior in a hole-box conditioning task if model metaparameters are dynamically controlled on the basis of the mouse's genotype and phenotype, stress conditions, recent performance feedback and pharmacological manipulations of adrenergic alpha-2 receptors. We find that stress and motivation affect behavioral performance by altering the exploration-exploitation balance in a genotype-dependent manner. Our results also provide computational insights into how an inverted U-shape relation between stress/arousal/norepinephrine levels and behavioral performance could be explained through changes in task performance accuracy and future reward discounting