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D MacDonald

Publications and source records attributed to D MacDonald.

162 records · Page 9Linked to original sources
PubMedDate not supplied

The PTL, Combitube, laryngeal mask, and oral airway: a randomized prehospital comparative study of ventilatory device effectiveness and cost-effectiveness in 470 cases of cardiorespiratory arrest.

PURPOSE: A prehospital study was conducted to assess and compare three alternative airway devices and the oral airway for use by non-Advanced Life Support emergency medical assistants (EMAs). METHOD: A modified randomized crossover design was used. The Pharyngeal Tracheal Lumen Airway (PTL), the laryngeal mask (LM), and the esophageal tracheal Combitube (Combi) were compared objectively for success of insertion, ventilation, and arterial blood gas and spirometry measurements performed upon hospital arrival. Subjective assessment was carried out by EMAs and receiving physicians at the time of device use, and an eight-question comparative evaluation of all devices was completed by EMAs at study conclusion. A comparative cost analysis was performed. Operating room training was compared with mannequin training for the LM. Autopsy findings and survival to hospital discharge were analyzed. The study took place in four non-ALS communities over four and a half years, and involved 470 patients in cardiac and/or respiratory arrest. EMAs had automatic external defibrillator training but no endotracheal intubation skills. RESULTS: Successful insertion and ventilation: Combi, 86%; PTL, 82%; LM, 73% (p = 0.048). No significant difference was found for objective measurements of ventilatory effectiveness (ABGs and spirometry). Significant comparative differences in subjective evaluation were found. CONCLUSIONS: The PTL, LM, and Combi appear to offer substantial advances over the OA/BVM system. Although the most costly, the Combitube was associated with the least problems with ventilation and was the most preferred by a majority of EMAs.

Aged↗
PubMedDate not supplied

Human cingulate and paracingulate sulci: pattern, variability, asymmetry, and probabilistic map.

Recent advances in functional neuroimaging of the human cerebral cortex revived interest in the study of the cortical morphology at both macro- and microscopic levels. By means of high-resolution magnetic resonance imaging (MRI), in vivo images of the human brain can be acquired and used to aid localization of the functional maps. The goal of the present study was to determine variability in the occurrence and location of the cingulate sulcus (CS) and the paracingulate sulcus (PCS). Brain MRIs of 247 healthy young volunteers were obtained and transformed into a standardized stereotaxic space (Talairach and Tournoux, 1988). The CS and PCS were marked in 494 hemispheres using software capable of real-time movement through a 3-D volume. The markers were used to generate a probabilistic map of the CS and PCS. The individual MRI images were also evaluated for the presence and location of the following morphological features: the continuity of the CS, the presence of vertically oriented branches of the CS, the presence of the PCS, and the presence of the intralimbic sulcus. The results revealed considerable variability in the location of some of the above morphological features and a striking hemispheric asymmetry in the prominence of the PCS. The results of four previous blood-flow activation studies of speech control were used to illustrate the relevance of our morphological findings for functional neuroimaging of the human anterior cingulate cortex.

Adolescent↗
PubMedDate not supplied

Detection and mapping of abnormal brain structure with a probabilistic atlas of cortical surfaces.

PURPOSE: We have devised, implemented, and tested a technique for creating a comprehensive probabilistic atlas of the human cerebral cortex, based on high-dimensional fluid transformations. The goal of the atlas is to detect and quantify subtle and distributed patterns of deviation from normal cortical anatomy, in a 3D brain image from any given subject. METHOD: Given a 3D MR image of a new subject, a high-resolution surface representation of the cerebral cortex is automatically extracted. The algorithm then calculates a set of high-dimensional volumetric maps, fluidly deforming this surface into structural correspondence with other cortical surfaces, selected one by one from an anatomic image database. The family of volumetric warps so constructed encodes statistical properties of local anatomical variation across the cortical surface. Additional strategies are developed to fluidly deform the sulcal patterns of different subjects into structural correspondence. A probability space of random transformations, based on the theory of anisotropic Gaussian random fields, is then used to encode information on complex variations in gyral and sulcal topography from one individual to another. A complete system of 256(2) probability density functions is computed to reflect the observed variability in stereotaxic space of the points whose correspondences are found by the warping algorithm. Confidence limits in stereotaxic space are determined for cortical surface points in the new subject's brain. RESULTS: Color-coded probability maps are generated, which highlight and quantify regional patterns of deformity in the anatomy of new subjects. These maps indicate locally the probability of each anatomic point being as unusually situated, given the distributions of corresponding points in the scans of normal subjects. 3D MRI volumes are analyzed, from subjects with clinically determined Alzheimer disease and age-matched normal subjects. CONCLUSION: Applications of the random fluid-based probabilistic atlas include the transfer of multisubject 3D functional, vascular, and histologic maps onto a single anatomic template, the mapping of 3D atlases onto the scans of new subjects, and the rapid detection, quantification, and mapping of local shape changes in 3D medical images in disease and during normal or abnormal growth and development.

Aged↗
PubMedDate not supplied

A four-dimensional probabilistic atlas of the human brain.

The authors describe the development of a four-dimensional atlas and reference system that includes both macroscopic and microscopic information on structure and function of the human brain in persons between the ages of 18 and 90 years. Given the presumed large but previously unquantified degree of structural and functional variance among normal persons in the human population, the basis for this atlas and reference system is probabilistic. Through the efforts of the International Consortium for Brain Mapping (ICBM), 7,000 subjects will be included in the initial phase of database and atlas development. For each subject, detailed demographic, clinical, behavioral, and imaging information is being collected. In addition, 5,800 subjects will contribute DNA for the purpose of determining genotype- phenotype-behavioral correlations. The process of developing the strategies, algorithms, data collection methods, validation approaches, database structures, and distribution of results is described in this report. Examples of applications of the approach are described for the normal brain in both adults and children as well as in patients with schizophrenia. This project should provide new insights into the relationship between microscopic and macroscopic structure and function in the human brain and should have important implications in basic neuroscience, clinical diagnostics, and cerebral disorders.

Adolescent↗
PubMedDate not supplied

Hope and Hanukkah.

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Attitude of Health Personnel↗
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Portrait of Jake.

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Aged↗
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Empowering the eyes and ears of hospice: The Aide Specialist program.

Home aides are the critical link between the goals of hospice and their implementation. They spend greater periods of time in the home than other hospice team members, and often enjoy a privileged relationship of trust and openness with the patient and family. In order to optimize the contribution hospice aides can make. The Hospice of Central New York developed a program designed to improve hospice care quality by enhancing the skills, sensitivity, and self-esteem of the home health aides who most regularly provide this care. This article describes the components of a successful hospice aide training and support program, discusses the techniques used and the evaluation measures employed, and summarizes the benefits, limitations and challenges of initiating and maintaining a program of this kind.

Clinical Competence↗
PubMedDate not supplied

The struggle for the soul of hospice: stress, coping, and change among hospice workers.

This article reports preliminary findings from an ongoing study of occupational stress, coping, and change among employees at a hospice in New York state. The study sought to identify those aspects of hospice work that direct-service and middle-management staff considered unique and rewarding, and also to examine those conditions that created problematic levels of stress. A qualitative methodology was employed, based on heuristic principles of grounded theory and action research. Techniques included field observation and participation, 38 semi-structured interviews, and group discussion and review of data by research participants. The authors elaborate upon established models of occupational stress and coping, and identify hospice-specific stressors and resources for coping. The research highlights "support" as a critically important, multidimensional element for successful coping. A re-examination and reinterpretation of "coping" as it applies to stress in hospice work is suggested.

Adaptation, Psychological↗
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Making waves.

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First Aid↗