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Methods: Thirty-six elective surgical patients were initially enrolled. Conditions approximating steady state were obtained for sevoflurane and target-controlled propofol infusions. Patients were sequentially evaluated for LOC (loud voice plus mild prodding) and immobility to surgical incision. The study was designed using the Dixon up-down method.
Results: The observed propofol effect target with 50% response plus sevoflurane (0.46% end-tidal concentration) was 1.2 [mu]g/ml (95% confidence interval, 1.1-1.3 [mu]g/ml). It was not significantly different from that predicted (1.5 [mu]g/ml; 95% confidence interval, 1.2-1.7 [mu]g/ml) by simple additivity. The effective plasma concentration of propofol that suppressed movement to skin incision in 50% of patients was 5.4 [mu]g/ml (95% confidence interval, 4.8-6.0 [mu]g/ml) plus sevoflurane (0.86%) and was not significantly different from that predicted by additivity (5.4 [mu]g/ml; 95% confidence interval, 4.8-5.9 [mu]g/ml). Both analyses had adequate power (90%) to detect a significant change (+/-19 to 25%) from predicted value. Repeated-measures analysis of variance identified a Bispectral Index value of 70 as the break point between those who responded at LOC or did not. 相似文献
Background
Due to improved surgical techniques and more efficient decision making in treating severely injured patients, survival rates have increased over the years. This study was initiated to evaluate the incidence and identify risk factors for developing posttraumatic stress symptoms, using both extensive trauma-related data and data assessing the psychological trauma, in a population of severely injured patients.Patients and methods
79 patients admitted to the Department of Multitrauma and Spinal Cord Injury at Sunnaas Rehabilitation Hospital from 2003 to 2005, prospectively completed semistructured psychological interviews and questionnaires, such as Impact of Event Scale-Revised. In addition, extensive injury-related data, such as injury severity score (ISS), new injury severity score (NISS), and probability of survival (PS) were collected.Results
39% had multiple trauma, 34% had multiple injuries including spinal cord injuries, and 27% had isolated spinal cord injuries. Mean NISS was 31.5 (S.D. 13.7). 6% met diagnostic criteria for posttraumatic stress disorder (PTSD) and 9% met the criteria for subsyndromal PTSD. Injury-related data did not influence the prevalence of posttraumatic stress symptoms, however, some psychosocial variables did have a significant impact.Conclusions
We found a low incidence of PTSD and subsyndromal PTSD. No significant differences were found between the patients suffering from posttraumatic stress symptoms and the non-symptoms group in relation to injury-related data such as ISS/NISS, PS, or multiple trauma versus spinal cord injury. The most evident risk factors for developing posttraumatic stress symptoms were symptoms of anxiety, female gender and negative attitudes toward emotional expression. 相似文献Objective: To characterize polysensitized patients regarding occurrence, duration and course of dermatitis, and examine potential risk factors for polysensitization, including atopic eczema.
Methods: A questionnaire case–control study of 562 polysensitized and 1124 single/double-sensitized individuals was performed.
Results: The results show that 45% of polysensitized and 31% of single/double-sensitized patients had or had had atopic eczema, and atopic eczema was identified as a risk factor for polysensitization. Patients with leg ulcer constituted only a minor part of the polysensitized group and leg ulcers were not identified as a risk factor for polysensitization in this study. The influence of contact allergies on duration and course of disease diverged between the group of patients with atopic eczema and the group without atopic eczema.
Conclusion: Patients with atopic eczema were overrepresented in the group of polysensitized patients and polysensitized patients should be viewed in the light of occurrence or lack of atopic eczema. 相似文献