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Abstract. Objectives:To describe the outcomes of a mass carbon monoxide (CO) intoxication, and to calculate the CO half-life in a pediatric school-aged population.
Methods:A retrospective chart review was performed based on Regional Poison Center database information, hospital laboratory data, and medical records of the pediatric patients who sought care at one of 3 St. Louis area hospitals, after exposure to high levels of CO. Exposures occurred on January 5, 1996, after evidence of a CO leak was discovered at an area elementary school. Charts were reviewed for major demographics, symptoms reported, carboxyhemoglobin (COHb) levels and times, and level of effect.
Results:Information about 177 (35%) of the 504 children in attendance at school that day was available. Mean age was 8.7 ± 1.8 years (range 4–12 years). Symptoms were present in 155 (88%) of the 177 children for whom data were available. Initial COHb levels were obtained for 147 (83.1%) of the 177 children. First mean COHb level was 7.0% (95% CI = 6.6–7.5%). Second COHb level was obtained for 26 children with a mean of 2.7% (95% CI = 2.2–3.2%). Calculated half-life of COHb, on 100% 02 at 1 atm, was 44.0 minutes (95% CI = 39.6–48.2 minutes).
Conclusion:Some children had symptoms at COHb levels that traditionally have been considered nontoxic. The elimination of COHb was found to be more rapid in this population of children than reported in other studies.  相似文献   
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Background  

Cerebrospinal fluid (CSF) pleocytosis may be seen in asymptomatic HIV-infected individuals. This finding complicates interpretation of CSF abnormalities when such individuals are evaluated for other central nervous system infections. The goal of this study was to determine the relationship between CSF pleocytosis, central nervous system (CNS) antiretroviral penetration, adherence to antiretroviral medication regimens, neurological symptoms and performance on neuropsychological tests.  相似文献   
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BACKGROUND AND AIMS: Assessment of health-related quality of life (HRQOL) is not routinely reported in the literature on chronic liver disease (CLD). Few studies have examined quality of life (QOL) in patients with primary biliary cirrhosis (PBC) despite its significant functional impact. One of the reasons for the lack of HRQOL measurement in patients with PBC may be the absence of a well-recognized and widely used measure that clinicians can use in ordinary clinical practice. The aim of this study is to evaluate HRQOL measures used in patients with PBC and examine the suitability of the measures for these patients. METHODS: A literature search identified reports that focused on any aspect of QOL in patients with PBC. Key texts were identified containing generic, domain-specific, and condition-specific measures. The identified measures were systematically evaluated for appropriateness, acceptability, reliability, validity, precision, and responsiveness. RESULTS: Twenty measures were identified from 9 key texts. Six of the measures were previously validated generic measures; 10 were domain-specific measures previously used to measure fatigue, depression, and psychological distress in general and psychiatric populations; and 4 measures had been developed in patients with CLD. Reporting of reliability and validity generally was consistent for all measures used. However, reporting of the remaining criteria was variable, particularly in relation to responsiveness over time and acceptability of the measures to patients with PBC. CONCLUSIONS: A clearer and more rigorous approach is needed in reporting the properties of HRQOL measures used in patients with PBC to help clinicians decide which measures are most suitable for these patients.  相似文献   
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Information about how Thai school-age children perceive fear is necessary for the development of culturally appropriate anxiety or fear measures. The purpose of this study was to describe Thai school-age children's perceptions of fear from their own perspective. Qualitative data from 13 Thai students in Grades 3 to 6 in three schools in Bangkok were obtained by semistructured, formal interviews, combined with drawings. The data were analyzed using content analysis within the frame of category development in the grounded theory method. Several culturally specific aspects of fear were revealed. This information is useful for health care providers caring for Thai children. The results of this study also illustrate the importance of carefully assessing children from culturally diverse backgrounds related to manifestations of anxiety or fear.  相似文献   
79.
OBJECTIVE: To identify the etiology and impact of preterm delivery in twin gestations. STUDY DESIGN: Twin gestations delivered at 33.0 to 36.9 weeks were identified in a perinatal database, and categorized by indication for delivery. Deliveries were identified as indicated, or non-indicated (discretionary). Neonatal outcomes were measured by birth weight, length of stay, NICU admission, and ventilator utilization. Data were divided and analyzed by indicated or discretionary delivery, and gestational age at delivery. RESULTS: Analyzed were 3252 twin gestations (6504 infants), with 78% having indicated delivery. Of the 22% with discretionary delivery, nearly 40% required NICU admission. With each advancing week of gestation, there was a significant decrease in incidence of NICU admission and nursery days. CONCLUSION: The majority of preterm deliveries were indicated, though 22% were discretionary. It is vital to consider neonatal morbidity and costs related to gestational age when choosing discretionary delivery.  相似文献   
80.
BACKGROUND: We have observed that dosimeter-run nebulizers have a much smaller output when manually activated than when breath activated; however, this has not been adequately investigated. OBJECTIVE: To evaluate the effect of different calibration methods on nebulizer output. METHODS: Six healthy subjects performed all calibrations. The nebulizers were operated by 2 different dosimeters and were calibrated to produce 9 microL per actuation by breath activation followed by exhalation to the room. The nebulizers were then operated at these identical settings, and the output determined in 3 ways: (1) breath activation followed by exhalation to the room, (2) breath activation with exhalation into the nebulizer, and (3) manual activation (with no subject using the nebulizer). These 3 methods were termed regular, rebreathe, and manual, respectively. RESULTS: There was a large and statistically significant difference in nebulizer output among the 3 methods. The measured rebreathe outputs (5.6 and 5.7 microL per actuation) were approximately two thirds and the manual outputs (3.2 and 3.9 microL per actuation) were approximately one third of the regular calibration outputs (8.6 and 8.9 microL per actuation); the 2 values are for the 2 dosimeters. The results were highly statistically significant (P < .001). CONCLUSIONS: The method by which a nebulizer-dosimeter system is calibrated results in different nebulizer outputs. This has a high likelihood of influencing the concentration of methacholine causing a 20% decrease in volume in the first second of forced expiration.  相似文献   
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