Organic geochemistry

Organic geochemical research on origin of lif

Hyperoxia after cardiac arrest may not increase ischemia-reperfusion injury

In the last decade, moderate hypothermia has become the mainstay of treatment in the post-resuscitation period. However, for the damaged brain, optimizing oxygen transport, including arterial oxygenation, may also be important. The current view states that hyperoxia in the immediate post-resuscitation period may worsen cerebral outcome, and international guidelines recommend a target arterial oxygen saturation of 94% to 98%. An article in the previous issue of Critical Care challenges this viewpoint. In an elegant study using a Cox proportional hazards model combined with sensitivity analyses and time period matching, the authors show no independent association between hyperoxia and in-hospital mortality. The present commentary discusses these contradictory findings and suggests a practical solution to solve these differences

Pricing in the hotel and catering sector

A model explaining gross margins in the hotel and catering sector is developed. A cost-mark-up model for the retail sector is used as a starting point. Although we have to reject the hypothesis of mark-up pricing in the hotel and catering sector, the model proves a useful instrument to discriminate between such influences as sales composition, costs and their various components, scale and demand conditions on price setting. Our empirical evidence stems from the Dutch hotel and catering sector (1977 through 1981)

Intravenous magnesium in subarachnoid hemorrhage

Contains fulltext : 97062.pdf (publisher's version ) (Open Access

Comparison of cooling methods to induce and maintain normo- and hypothermia in intensive care unit patients: a prospective intervention study

Contains fulltext : 52086.pdf ( ) (Open Access)BACKGROUND: Temperature management is used with increased frequency as a tool to mitigate neurological injury. Although frequently used, little is known about the optimal cooling methods for inducing and maintaining controlled normo- and hypothermia in the intensive care unit (ICU). In this study we compared the efficacy of several commercially available cooling devices for temperature management in ICU patients with various types of neurological injury. METHODS: Fifty adult ICU patients with an indication for controlled mild hypothermia or strict normothermia were prospectively enrolled. Ten patients in each group were assigned in consecutive order to conventional cooling (that is, rapid infusion of 30 ml/kg cold fluids, ice and/or coldpacks), cooling with water circulating blankets, air circulating blankets, water circulating gel-coated pads and an intravascular heat exchange system. In all patients the speed of cooling (expressed as degrees C/h) was measured. After the target temperature was reached, we measured the percentage of time the patient's temperature was 0.2 degrees C below or above the target range. Rates of temperature decline over time were analyzed with one-way analysis of variance. Differences between groups were analyzed with one-way analysis of variance, with Bonferroni correction for multiple comparisons. A p < 0.05 was considered statistically significant. RESULTS: Temperature decline was significantly higher with the water-circulating blankets (1.33 +/- 0.63 degrees C/h), gel-pads (1.04 +/- 0.14 degrees C/h) and intravascular cooling (1.46 +/- 0.42 degrees C/h) compared to conventional cooling (0.31 +/- 0.23 degrees C/h) and the air-circulating blankets (0.18 +/- 0.2 degrees C/h) (p < 0.01). After the target temperature was reached, the intravascular cooling device was 11.2 +/- 18.7% of the time out of range, which was significantly less compared to all other methods. CONCLUSION: Cooling with water-circulating blankets, gel-pads and intravascular cooling is more efficient compared to conventional cooling and air-circulating blankets. The intravascular cooling system is most reliable to maintain a stable temperature