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Objectives: Mild therapeutic hypothermia (MTH) is being used to improve neurological outcome and survival in patients successfully resuscitated after cardiac arrest. The impact on coagulation may be difficult to assess since most coagulation parameters are measured at 37°C and not at actual body core temperature. Therefore we investigated the effects of MTH both at body core (target) temperature of 32°C and at 37°C., Methods: Patients admitted at the ICU after cardiac arrest treated with MTH. Baseline blood samples, measured at 37°C were taken directly at arrival. The second and third samples were drawn within 1h and 24h after reaching target temperature and were measured at 32°C and 37°C. A final sample was drawn when the patient returned to normotemperature (measured at 37°C). Clotting time (CT) and maximum clotting formation (MCF) were measured with thromboelastometry., Results: Upon reaching target temperature (32°C) Extem and Intem CT were increased compared to baseline with 57s (49-75) to 65s (59-72) and 165s (144-183) to 193s (167-212) respectively (median with IQR; P<0.05), with a further significant increase after 24h of hypothermia with 68s (57-80) and 221s (196-266). Samples analyzed at 32°C showed a significant longer CT of 12s in Extem and 33s in Intem compared to 37°C. MCF was not affected by MTH or adjustment of temperature., Conclusion: The mild effect of MTH on coagulation parameters remains unidentified when measured at 37°C. Although measurements at 32°C differ from those at 37°C, this does not appear to be of clinical relevance as all values were still within the reference range., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

Objectives: Dilutional coagulopathy as a consequence of cardiopulmonary bypass (CPB) system priming may also be affected by the composition of the priming solution. The direct effects of distinct priming solutions on fibrinogen, one of the foremost limiting factors during dilutional coagulopathy, have been minimally evaluated. Therefore, the authors investigated whether hemodilution with different priming solutions distinctly affects the fibrinogen-mediated step in whole blood clot formation., Design: Prospective observational laboratory study., Setting: University hospital laboratory., Participants: Eight male healthy volunteers., Interventions: Blood samples diluted with gelatin-, albumin-, or hydroxyethyl starch (HES)-based priming solutions were ex-vivo evaluated for clot formation by rotational thromboelastometry., Measurements and Main Results: The intrinsic pathway (INTEM) coagulation time increased from 186 +/- 19 seconds to 205 +/- 16, 220 +/- 17, and 223 +/- 18 seconds after dilution with gelatin-, albumin-, or HES-containing prime solutions (all p < 0.05 v baseline). The extrinsic pathway (EXTEM) coagulation time was only minimally affected by hemodilution. Moreover, all 3 priming solutions significantly reduced the INTEM and EXTEM maximum clot firmness. The HES-containing priming solution induced the largest decrease in the maximum clot firmness attributed to fibrinogen, from 13 +/- 1 mm (baseline) to 6 +/- 1 mm (p < 0.01 v baseline)., Conclusions: All studied priming solutions prolonged coagulation time and decreased clot formation, but the fibrinogen-limiting effect was the most profound for the HES-containing priming solution. These results suggest that the composition of priming solutions may distinctly affect blood clot formation, in particular with respect to the fibrinogen component in hemostasis., (Copyright 2010 Elsevier Inc. All rights reserved.)

The international Brain Trauma Foundation guidelines recommend prehospital endotracheal intubation in all patients with traumatic brain injury (TBI) and a Glasgow Coma Scale (GCS)< or =8. Close adherence to these guidelines is associated with improved outcome, but not all severely injured TBI patients receive adequate prehospital airway support. Here we hypothesized that guideline adherence varies when skills are involved that rely on training and expertise, such as endotracheal intubation. We retrospectively studied the medical records of CT-confirmed TBI patients with a GCS< or =8 who were referred to a level 1 trauma centre in Amsterdam (n=127). Records were analyzed for demographic parameters, prehospital treatment modalities, involvement of an emergency medical service (EMS) and respiratory and metabolic parameters upon arrival at the hospital. Patients were mostly male, aged 45+/-21 years with a median injury severity score (ISS) of 26. Of all patients for whom guidelines recommend endotracheal intubation, only 56% were intubated. In 21 out of 106 severe cases an EMS was not called for, suggesting low guideline adherence. Especially those TBI patients treated by paramedics tended to develop higher levels of stress markers like glucose and lactate. We observed a low degree of adherence to intubation guidelines in a Dutch urban area. Main reasons for low adherence were the unavailability of specialized care, scoop and run strategies and absence of a specialist physician in cases where intubation was recommended. The discrepancy between guidelines and reality warrants changing practice to improve guideline compliance and optimize outcome in TBI patients.

We present a preliminary analysis of the 1-10 keV spectrum of the massive X-ray binary Cygnus X-3, obtained with the high-energy transmission grating spectrometer on the Chandra X-Ray Observatory. The source reveals a richly detailed discrete emission spectrum, with clear signatures of photoionization-driven excitation. Among the spectroscopic novelties in the data are the first astrophysical detections of a number of He-like "triplets" (Si, S, Ar) with emission-line ratios characteristic of photoionization equilibrium, fully resolved narrow radiative recombination continua of Mg, Si, and S, the presence of the H-like Fe Balmer series, and a clear detection of an approximately 800 km s-1 large-scale velocity field as well as an approximately 1500 km s-1 FWHM Doppler broadening in the source. We briefly touch on the implications of these findings for the structure of the Wolf-Rayet wind.

We present the first X-ray spectrum obtained by the Low-Energy Transmission Grating Spectrometer (LETGS) aboard the Chandra X-Ray Observatory. The spectrum is of Capella and covers a wavelength range of 5-175 Å (2.5-0.07 keV). The measured wavelength resolution, which is in good agreement with ground calibration, is Deltalambda approximately 0.06 Å (FWHM). Although in-flight calibration of the LETGS is in progress, the high spectral resolution and unique wavelength coverage of the LETGS are well demonstrated by the results from Capella, a coronal source rich in spectral emission lines. While the primary purpose of this Letter is to demonstrate the spectroscopic potential of the LETGS, we also briefly present some preliminary astrophysical results. We discuss plasma parameters derived from line ratios in narrow spectral bands, such as the electron density diagnostics of the He-like triplets of carbon, nitrogen, and oxygen, as well as resonance scattering of the strong Fe xvii line at 15.014 Å.

The Einstein Observatory, a large satellite dedicated to x-ray astronomy, carried the first large x-ray telescope to be placed in orbit and an objective grating spectrometer with two sets of gratings. This paper lists prelaunch calibration results and describes the derivation of spectrometer efficiency and resolution. Several calibration spectra are shown, and theoretical grating parameters are derived from the calibration results.

Efficiency and resolution measurements are reported of an x-ray transmission grating to be flown on board the European X-ray Observatory Satellite (EXOSAT). By optimizing the thickness of the grating bars, very high efficiencies can be obtained over a limited energy range. An absolute efficiency of 20% at 7.1 A decreasing to 10% above 15 A has been achieved, including all effects of support structure and mounting necessary to withstand space qualification. This means that 10% of the incoming radiation at 7.1 A results in the minus first spectral order and 10% in the plus first order. The measured resolution at the short wavelength end of the range (lambda > 20 A) is determined by the mirror resolution; at the longer wavelengths (300 A), the effects of coma and astigmatism dominate. The measured resolution at 304 A for the EXOSAT-mirror-grating system is 4.5 A in agreement with theoretical predictions.