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991.
Conclusions Although much attention is being given to the design of the anesthesia workstation of the next century, significant opportunities exist to improve current systems. There have been sufficient technological advances that enable immediate improvement on current techniques and methodologies. As this team realized, much can be done to improve the workstation of the immediate future.  相似文献   
992.
Background: For local anesthetics, the process of removal from the site of administration influences the duration of anesthesia and the risk for systemic toxicity to develop. The systemic absorption of epidural ropivacaine and the time profile of sensory and motor block were studied in healthy volunteers.

Methods: Nine persons simultaneously received 150 mg ropivacaine hydrochloride (7.5 mg/ml) epidurally and 40 mg deuterium-labeled (sup 2 H sub 3)ropivacaine hydrochloride (0.25 mg/ml) intravenously. Peripheral arterial and venous plasma samples were collected, and assessments of sensory and motor block were made.

Results: The arterial plasma concentrations increased faster than the venous concentrations, with 50% higher maximum concentrations after both intravenous and epidural administration. The absorption was biphasic. A correlation was seen between the duration of sensory block and the slower absorption half-life; that is, the longer the half-life, the longer the duration. The extent of spread varied among the volunteers, with the median upper block level not exceeding T12. The motor block (Bromage score 1) was of slower onset (median, 0.4 h) and of shorter duration (median, 4.1 h) than the sensory block (onset, 0.2 h; duration, 6.5 h at L2 medians).  相似文献   

993.
Objective: To determine which characteristics of older patients who use a hospital ED are associated with repeat visits during the 90 days following the index visit.
Methods: The study was conducted in the ED of a 400-bed university-affiliated acute care community hospital in Montreal. Patients aged ≥75 years who visited the ED between 08:00 and and 16:00 on a convenience sample of days over an 8-week period (July and August 1994) were assessed using a questionnaire, physical and cognitive status instruments, and a functional problem checklist. The hospital's administrative database was used to identify repeat visits during the 90 days following the ED visit. The representativeness of the sample was assessed by analyses of ED visits made by 4,466 persons aged ≥65 years during a 12-month period (September 1993 to August 1994) using the hospital's administrative database.
Results: 256 patients aged ≥75 years visited the ED during the study period and 167 were assessed. Of these, 54 (32%) were admitted to the hospital. Among the 113 patients released from the ED, 27 (24%) made repeat visits during the next 90 days. In univariate analyses, repeat visits were significantly associated with the number of functional problems, cognitive impairment, and previous ED visits. In multiple logistic regression, male gender, living alone, and number of functional problems were independent predictors of repeat visits. In the administrative data analyses, nighttime arrival to the ED for the index visit was significantly associated with repeat visits.
Conclusions: Self-reported risk factors can help to identify a group of elders likely to make repeated ED visits; the development of a screening instrument incorporating questions on these problems and implementation of appropriate interventions might improve these patients' quality of life and reduce the demand for further ED care in this age group.  相似文献   
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Extracardiac Direct Total Cavopulmonary Connection   总被引:2,自引:0,他引:2  
We report a successful extracardiac direct total cavopulmonary connection without prosthetic materials performed in a 3-year-old boy with tricuspid atresia, infundibular pulmonary stenosis, and normally positioned great arteries. The transected pulmonary trunk was bought down posterolaterally with respect to the right atrium and was anastomosed end-to-end with the inferior vena cava.  相似文献   
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