HIGHLIGHTING INTRACRANIAL-PRESSURE MONITORING IN PATIENTS WITH SEVERE ACUTE BRAIN TRAUMA

Intrcranial pressure (ICP) monitoring was carried out in 100 patients with severe acute brain trauma, primarily by means of a subarachnoid catheter. Statistical associations were evaluated between maximum ICP values and: 1) Glasgow Coma Scale (GCS) scores; 2) findings on computed tomography (CT) scans of the head; and 3) mortality. A significant association was found between low GCS scores (3 to 5) and high ICP levels, as well as between focal lesions on CT scans and elevated ICP. Mortality was significantly higher in patients with ICP > 40 mm Hg than in those;vith ICP less than or equal to 20 mm Hg.533A39039

Remote Sensing Image Representation based on Hierarchical Histogram Propagation

International audienceMany methods have been recently proposed to deal with the large amount of data provided by high- resolution remote sensing technologies. Several of these methods rely on the use of image segmentation algorithms for delineating target objects. However, a common issue in geographic object-based applications is the definition of the appropriate data representation scale, a problem that can be addressed by exploiting multiscale segmentation. The use of multiple scales, however, raises new challenges related to the definition of effective and efficient mechanisms for extracting features. In this paper, we address the problem of extracting histogram-based features from a hierarchy of regions for multiscale classification. The strategy, called H-Propagation, exploits the existing relation- ships among regions in a hierarchy to iteratively prop- agate features along multiple scales. The proposed method speeds up the feature extraction process and yields good results when compared with global low- level extraction approaches

Remote Sensing Image Representation based on Hierarchical Histogram Propagation

International audienceMany methods have been recently proposed to deal with the large amount of data provided by high- resolution remote sensing technologies. Several of these methods rely on the use of image segmentation algorithms for delineating target objects. However, a common issue in geographic object-based applications is the definition of the appropriate data representation scale, a problem that can be addressed by exploiting multiscale segmentation. The use of multiple scales, however, raises new challenges related to the definition of effective and efficient mechanisms for extracting features. In this paper, we address the problem of extracting histogram-based features from a hierarchy of regions for multiscale classification. The strategy, called H-Propagation, exploits the existing relation- ships among regions in a hierarchy to iteratively prop- agate features along multiple scales. The proposed method speeds up the feature extraction process and yields good results when compared with global low- level extraction approaches

Cerebral hemometabolism: variability the acute phase of traumatic coma

Objective: to evaluate the interrelationships between cerebral and systemic hemometabolic alterations in patients with severe traumatic brain injury managed according to a standardized therapeutic protocol. Design: prospective, interventional study in patients with traumatic coma. Setting: a general Intensive Care Unit in a teaching hospital. Patients and methods: twenty-seven patients (21M e 6F), aging 14-58 years, with severe acute brain trauma, presenting with three to eight points on the Glasgow Coma Scale, were prospectively evaluated according to a cumulative protocol for the management of acute intracranial hypertension, where intracranial pressure (ICP) and cerebral extraction of oxygen (CEO3) were routinely measured. Hemometabolic interrelationships involving mean arterial pressure (MAP), ICP, arterial carbon dioxide tension (PaCO2), CEO2, cerebral perfusion pressure (CPP) and systemic extraction of oxygen (SEO2) were analyzed. Interventions: routine therapeutic procedures. Results. no correlation was found between CEO2 and CPP (r = -0.07; p = 0.41). There was a significant negative correlation between PaCO2 and CEO2 (r = -0.24; p = 0.005) and a positive correlation between SEO2 and CEO2 (r = 0.24; p = 0 01). The mortality rate in this group of patients was 25.9% (7/27). Conclusion: 1) CPP and CEO2 are unrelated; 2) CEO2 and PaCO2 ore closely related; 3) during optimized hyperventilation, CEO2 and SEO2 are coupled.583B87788

Vasopressin serum levels in patients with severe brain lesions and in brain-dead patients

Introduction: Patients with severe brain lesions (SBL) and brain-dead patients (BD) frequently present with vasopressin (AVP) secretion disorders. Objective: To evaluate AVID serum levels in SBL and BD patients. Design: Prospective, open label, observational trial. Setting: A general teaching hospital. Method: Three groups of adult subjects (age greater than or equal to 18y) of both sexes were included in this study: control group: 29 healthy volunteers; SBL group: 17 patients with Glasgow Coma Scale (GCS): less than or equal to8; and BD group: 11 brain-dead patients. Samples of venous blood were collected in the morning at rest from healthy volunteers and at 8 hourly intervals over a period of 24h from SBL and BID patients for AVP determinations. Concomitantly, some clinical and laboratorial variables were also recorded. Results: AVP serum levels (pg/ml) were [mean (SD); median]: control [2.2(1.1); 2.01; SBL [5.7(6.3); 2.9]; and BID [2.6(1.0); 2.81. AVID serum levels varied greatly in SBL patients, but without statistically significant difference in relation to the other groups (p=0.06). Hypotension (p=0.02), hypernatremia (p=0.0001), serum hyperosmolarity (p=0.0001) and urinary hypoosmolarity (p=0.003) were outstanding in BD patients when compared with SBL. Conclusions: The AVP serum levels did not demonstrate significant statistical difference between the groups, only showing a greater variability in SBL patients (manifested as serum spike levels). Hypernatremia and hyperosmolarity were present in BD patients, indicating a failure of the hypothalamic-pituitary system in AVP production and release.622A22623