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41.
Carlos E Rodriguez Martinez Maria C Guzman Juan M Castillo Monica P Sossa Paulina Ojeda 《Pediatric critical care medicine》2006,7(4):335-339
OBJECTIVE: The primary goal of this study was to evaluate the validity of the North American-European Consensus Committee (NAECC) definition for acute respiratory distress syndrome (ARDS) in pediatric patients. A secondary aim was to evaluate the threshold value for the PaO2/FiO2 ratio, used to determine which pediatric patients have ARDS. DESIGN: Retrospective cohort study. SETTING: Pediatric intensive care unit. PATIENTS: Pediatric intensive care unit patients who required mechanical ventilation, died, and underwent autopsy between January 1, 1996, and December 31, 2002 (n = 34). INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Clinical and chest radiograph information was collected retrospectively through chart review using a standardized data collection tool. Data included the criteria specified in the NAECC definition of ARDS and demographic information. We calculated the sensitivity, specificity, positive predictive value, negative predictive value, and likelihood ratio of clinical diagnosis of ARDS compared with a pathologic diagnosis. The threshold value of PaO2/FiO2 was identified by plotting receiver operating characteristics curves and comparing the areas under the curves. The NAECC definition yielded a sensitivity of 80.7% (95% confidence interval 60-92%), specificity of 71.4% (95% confidence interval 30-95), positive predictive value of 91.3% (95% confidence interval 70-98), negative predictive value of 50.0% (95% confidence interval 20-78), and likelihood ratio of 2.82. A PaO2/FiO2 <150 had a slightly higher (but not significantly different) specificity for ARDS than a value >200 (71% vs. 86%, p = .15) without changing sensitivity. CONCLUSIONS: Our study suggests the need for further research with larger number of children to identify an optimal Pao2/Fio2 threshold for identifying ARDS in this population. 相似文献
42.
Experience with hemoperfusion for organophosphate poisoning. 总被引:6,自引:0,他引:6
J Martinez-Chuecos M del Carmen Jurado M Paz Gimenez D Martinez M Menendez 《Critical care medicine》1992,20(11):1538-1543
OBJECTIVE: To evaluate the usefulness of extracorporeal clearance techniques in the treatment of organophosphate poisoning, particularly hemoperfusion. DESIGN: Retrospective study. SETTING: An ICU of a general hospital. PATIENTS: Ten patients with organophosphate poisoning initially received classic treatment with gastric lavage and washing of the whole skin surface, as well as the administration of cathartics, activated charcoal, atropine, and obidoxime or pralidoxime. All patients underwent one to three hemoperfusions. MEASUREMENTS AND MAIN RESULTS: Plasma insecticide concentrations and cholinesterase activity were determined daily. Two to three biopsies of fat tissue were carried out at 1- to 2-wk intervals. The amount of the insecticide removed during hemoperfusions was also determined. Five patients presented with a prolonged nicotinic syndrome. Two of these patients showed sequelae of delayed neurotoxicity. Another two of the five patients died and the remaining patient recovered without sequelae. In none of the patients could > 0.1% of the total absorbed poison be removed by hemoperfusion. No changes in symptoms were observed after these procedures. Fat tissue concentrations of the insecticide were 20 to 50 times higher than the concentrations in plasma. Atropine decreased the intestinal transit time, and 10 days after poisoning, a powerful cathartic treatment indicated the persistence of gut content, which probably caused prolonged absorption of the toxin. CONCLUSIONS: Extracorporeal cleansing mechanisms did not remove any clinically important amount of insecticide from our patients due to the high lipid solubility of these agents and no changes in symptoms were observed after these methods. The use of atropine decreases bowel peristalsis. Early use of powerful cathartics could avoid protracted absorption of the poison stored in the gut, although the potential benefits of this therapy require confirmation by the performance of prospective, controlled investigations. 相似文献
43.
I Pascual-Castroviejo M C Roche V Martinez Fernndez M Perez-Romero R M Escudero J J Garcia-Peas M Sanchez 《AJNR. American journal of neuroradiology》1994,15(8):1521
PURPOSETo describe the MR findings in eight girls and women with incontinentia pigmenti, from two families. Four had skin lesions and neurologic disease, and four had only skin lesions.METHODSEight patients had physical examination, family history, electroencephalogram and MR examination of the brain. MR was repeated in the two cases with more severe changes several years after the first study.RESULTSMR revealed brain changes only in the four patients who had neurologic disease associated with the cutaneous lesions of incontinentia pigmenti. Abnormalities were located in the cerebral hemisphere contralateral to the most affected side of the body. In two cases, the MR changes were subjacent to the scalp areas where the most severe cutaneous lesions were located in the neonatal period. Hypoplasia of the corpus callosum, probably secondary to atrophy of one or both cerebral hemispheres, and abnormal signal and atrophy of the lateral regions of one of the cerebellar hemispheres also were found in all four cases. Although the changes were seen in both the T1- and T2-weighted images, they were most evident in the latter. The four patients in the fourth stage who had only cutaneous lesions without neurologic problems did not reveal any MR abnormalities.CONCLUSIONSThis study demonstrates MR signal changes and focal atrophy of the cerebrum, cerebellum, and corpus callosum in patients with incontinentia pigmenti and neurologic disorders. The MR images appear normal in patients with incontinentia pigmenti who have no neurologic abnormalities. 相似文献
44.
45.
Stable isotope methodologies offer a number of possibilities for the nutritional assessment of many different processes and metabolic pathways. The application of stable isotopes has been boosted by the development of new mass spectrometers, lower costs of probes, and the risks associated with radioactive tracers. The use of 13 C as a tracer offers all the advantages of stable isotopes and has been widely applied for measuring various types of metabolic processes. This review is focused on clinical and nutritional assessments using 13 C breath tests. 相似文献
46.
47.
M Espada C Pedregal A Alonso C López L Salazar M M Martinez J L Guillén A R Martinez 《Il Farmaco; edizione pratica》1990,45(11):1237-1243
The synthesis of new N3-arylciclohexanespiroimidazolidine-2,4-diones, N3-arylciclohexanespiroimidazolidine-2-tio-4-ones and the 4-hydroxy derivatives is described and their structures discussed on the basis of I.R. and 1H-N.R.M. data. The anthelmintic activity of these compounds was tested. 相似文献
48.
49.
Student near-peer co-tutors in PBL groups 总被引:1,自引:0,他引:1
50.