Can latent heat safely warm blood? – in vitro testing of a portable prototype blood warmer

This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.Background Trauma/retrieval patients are often in shock and hypothermic. Treatment of such patients usually involves restoring their blood volume with transfusion of blood (stored at 2°C – 6°C) and/or crystalloids or colloids (stored at ambient temperature). Rapid infusion of these cold fluids can worsen or even induce hypothermia in these patients. Warming of intravenous fluids at accident sites has traditionally been difficult due to a lack of suitable portable fluid warmers that are not dependent on mains electrical or battery power. If latent heat, the heat released when a liquid solidifies (an inherently temperature limiting process) can warm intravenous fluids, portable devices without a reliance on electrical energy could be used to reduce the incidence of hypothermia in trauma patients. Methods Rapid infusion of red cells into patients was timed to sample typical clinical flow rates. An approved dry heat blood warmer was compared with a prototype blood warmer using a supercooled liquid latent heat storage material, to warm red cells whilst monitoring inlet and outlet temperatures. To determine the effect of warming on red cell integrity compared to the normal storage lesion of blood, extracellular concentrations of potassium, lactate dehydrogenase and haemoglobin were measured in blood which had been warmed after storage at 2°C – 6°C for 1 to 42 days. Results A prototype latent heat fluid warmer consistently warmed red cells from approximately 4°C to approximately 35°C at typical clinical flow rates. Warming of stored blood with latent heat did not affect red cell integrity more than the approved dry heat blood warmer. Conclusion Using latent heat as an energy source can satisfactorily warm cold blood or other intravenous fluids to near body temperature, without any adverse affects

CMS physics technical design report : Addendum on high density QCD with heavy ions

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Correction to: Cluster identification, selection, and description in Cluster randomized crossover trials: the PREP-IT trials

An amendment to this paper has been published and can be accessed via the original article

Trends and Disparities Among Diabetes-Complicated Births in Minnesota, 1993–2003

We used Minnesota birth certificate data from 1993–2003 to test 2 hypotheses: rates of diabetes-complicated pregnancy are increasing, and disparities between more and less socially advantaged groups are widening. Significant increases occurred in rates (per 1000 live births) of prepregnancy and gestational diabetes mellitus (from 2.6 to 4.9 and 25.6 to 34.8, respectively). Increases were significant in all demographic groups except gestational diabetes among American Indian mothers, and disparities worsened among all groups. Targeted interventions and surveillance improvements are needed