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991.
Two case reports in which a ventilating tube exchanger was used during tracheostomy in patients with potential for difficult reintubation are presented. We recommend leaving the ventilating tube exchanger in place for 48 hours to allow reintubation from above in the event of inadvertent decannulation in cases where difficult intubation is anticipated.Ventilating tube exchangers have been used to assist in the management of difficult airways in a variety of ways. These methods include the use of ventilating tube exchangers as malleable stylets, endotracheal tube exchangers and conduits through which oxygen can be delivered. We present two cases in which a ventilating tube exchanger was used as an adjunct to airway management in a novel fashion.  相似文献   
992.
Morbid results of prolonged intubation after coronary artery bypass surgery   总被引:3,自引:0,他引:3  
Cohen AJ  Katz MG  Frenkel G  Medalion B  Geva D  Schachner A 《Chest》2000,118(6):1724-1731
OBJECTIVES: This study evaluated the morbid results of prolonged intubation after coronary artery bypass grafting (CABG). METHODS: Over 30 months, 66 of 1,112 patients undergoing CABG required prolonged intubation. They were matched with 66 patients who did not require prolonged intubation. Preoperative and operative variables were evaluated to determine which would predict prolonged intubation. The postoperative courses were then compared to evaluate the effect of prolonged intubation. The study population was divided into three groups: those who underwent early extubation, but required reintubation (n = 24); those who required initial prolonged intubation, but no reintubation (n = 22); and those who required initial prolonged intubation and reintubation (n = 20). RESULTS: Univariate analysis revealed unstable angina (p = 0.037), elevated creatinine (p = 0.001), reduced FEV(1) (p = 0.019), longer cardiopulmonary bypass time (p = 0.009), and a greater positive fluid balance at 24 h (p = 0.0001) as predictors of postoperative prolonged intubation. Multivariate regression analysis revealed elevated creatinine (p = 0.011), FEV(1) (p = 0.022), and fluid balance (p = 0.001) as predictors of prolonged intubation. The study population had longer ICU and hospital stays (p = 0.0001), with more infectious complications (p = 0.0001) and higher mortality (p = 0. 001). In the subgroups of the study population, patients not requiring reintubation had shorter ICU (p = 0.001) and hospital stays (p = 0.0001), fewer infectious complications (p = 0.0001), and reduced mortality (p = 0.0001). CONCLUSIONS: Patients undergoing CABG with reduced FEV(1), renal failure, and positive fluid balance 24 h postoperatively are at risk for prolonged intubation. Prolonged intubation results in significant acute and midterm morbidity and mortality. Early extubation followed by reintubation further increases morbidity and mortality rates in these patients.  相似文献   
993.
Migration is one of the structural factors associated with HIV infections, but the dynamic and complex role of migrant situations as determinants of HIV-related vulnerability is still a major issue for social science research. Moreover, interventions to address the specific structural and contextual factors inherent in this association are limited and many do not take into account the cultural components. This paper presents a multi-level framework for analysis of the links between migration and HIV. It includes the association of migration with structural macro factors-lower socio-economic status and limited power in the new society; intermediate structural factors-limited social capital and bi-directional interaction of cultural norms; and individual-level factors-stressors unique to the migration context, depleted psychosocial resources, loss of cultural beliefs and low use of health services. All these factors affect risky sexual behaviour and transmission of HIV. The paper utilises those elements of the framework that are relevant to the specific needs of immigrant populations from the former Soviet Union and from Ethiopia in Israel. We demonstrate their application to integrated, multi-level HIV prevention interventions and propose several special principles for development of migration-related HIV prevention programmes.  相似文献   
994.
995.
In children, even minor trauma to the chest can result in cardiac injury. We describe a case of a 13-year-old boy who received blunt chest trauma during a motorcycle accident. He was initially symptom-free but later complained of persistent chest pain and a murmur was noted. An anterior muscular ventricular septal defect was detected one day after the accident, and a left ventricular pseudo-aneurysm developed days later. Both were successfully repaired 3 weeks after the injury.  相似文献   
996.
We have used human brain-derived endothelial cells (HBECs) maintained under basal culture conditions in a Boyden chamber assay system as an in vitro model of migration of cells of systemic immune origin across the blood brain barrier (BBB) during the initiation of a CNS-directed inflammatory response. In this study we evaluated the molecular mechanisms that regulate passage of ex vivo peripheral blood-derived monocytes across this barrier and the effects of such migration on the properties of both the HBECs and the monocytes. Our results indicate that monocytes can migrate across HBECs in the absence of inflammatory conditions, at rates exceeding those of lymphocytes. Monocyte migration could be significantly inhibited by the addition of blocking antibodies to intercellular adhesion molecule (ICAM)-1, very late antigen (VLA)-4 integrin, and monocyte chemoattractant protein (CCL-2/MCP-1), or treatment with tissue inhibitor of metalloproteinase (TIMP-1). Following monocyte migration there was a significant increase in permeability of soluble molecules and an enhanced rate of T cell migration across HBECs. The enhanced permeability could be partially prevented with anti-TNF-alpha antibody. The migration process did not induce the upregulation of either co-stimulatory molecules or chemokine receptors on the monocytes. These studies emphasize the functional role of monocyte-endothelial interactions in permitting target access of a CNS-directed cell-mediated immune response.  相似文献   
997.
Dotan ZA  Hana R  Simon D  Geva D  Pfeffermann RA  Ezri T 《Anesthesia and analgesia》2003,96(3):750-4, table of contents
We compared the effect of two doses of gentamicin versus no gentamicin (NG) given before surgery on the neuromuscular relaxant effect of vecuronium. Seventy patients (intraabdominal procedures) were randomly allocated to receive preoperative large-dose (4 mg/kg) gentamicin (LD), a modest dose (1.2 mg/kg) of gentamicin (MD), or NG. No more than one dose of gentamicin was given before the vecuronium administration. Serum gentamicin levels, the time for 25% recovery of the first twitch in the train-of-four after a bolus of vecuronium, and the time from cessation of the vecuronium infusion to extubation of the trachea were estimated. Serum gentamicin levels were higher (P < 0.001) for LD than MD. The time for 25% recovery of the first twitch after the vecuronium bolus was slightly longer with LD than MD (P = 0.06) and longer in LD than NG (P = 0.001) (42.9 +/- 23.6 min versus 36.2 +/- 17 min and 27.4 +/- 9 min, respectively). The time to extubation was similar with LD and MD and longer for LD than NG (P = 0.008) (34.7 +/- 19.2 min versus 27.4 +/- 19.3 min and 19.4 +/- 10.1 min, respectively). The differences in these times were insignificant between MD and NG. Gentamicin administered as a LD rather than MD enhanced the neuromuscular blockade of vecuronium as compared with NG given before surgery. IMPLICATIONS: We demonstrated that the neuromuscular relaxant effect of vecuronium is enhanced by a large (4 mg/kg) rather than a modest (1.2 mg/kg) dose of gentamicin as compared with no gentamicin given before surgery.  相似文献   
998.
BACKGROUND: Vacuum-assisted closure therapy is a novel treatment employed to aid wound healing in different areas of the body and recently also in sternotomy wounds. Aggressive vacuum-assisted closure treatment of the sternum in postoperative deep wound infection enhances sternal preservation and the rate of possible rewiring. METHODS: The records of 40 consecutive patients with deep sternal wound infection were reviewed. Sternal bone sparing was achieved by using layers of paraffin gauze (Jelonet; Smith and Nephew Medical, Hull, UK) at the bottom of the wound in order to cover and protect visible parts of the right ventricle, lung tissue, and grafts from the sternal edges. Two separate layers of polyurethane foam (KCI, Copenhagen, Denmark) were placed so as to fit between the sternal edges and subcutaneously. A continuous negative pressure of 125 mm Hg was applied and subsequent revision was made exclusively in nongranulation areas. RESULTS: There were no deaths during the 90 days of follow-up. Three late deaths unrelated to the infection and three subcutaneous fistulas occurred during the total follow-up period (3 to 41 months). The median duration of the vacuum-assisted closure therapy was 10 days (range, 3 to 34). The series represents a total of 474 days with the vacuum-assisted closure device without serious adverse events. CONCLUSIONS: In our opinion this modified vacuum-assisted closure therapy is a safe and reproducible option to bridge patients with postoperative deep sternal wound infection to complete healing. Reconstruction of the sternum was achieved in all patients without the use of muscle or omental flap surgery.  相似文献   
999.
Prenatal exposure to nicotine significantly increases enkephalin mRNA levels in the rat adrenal medulla prenatally, and postnatally the normal up-regulation is obliterated. This may lead to a disturbed modulation or regulation of catecholamine release in the adrenal and may be one factor contributing to the attenuated capacity of nicotine-treated pups to survive severe hypoxia. We speculate that this may be part of the mechanism underlying the relation between maternal smoking and sudden infant death syndrome.  相似文献   
1000.
We present a case of unilateral terminal transverse forearm deficiency with subterminal digit-like nubbins, identified in a fetus from a pregnancy terminated electively in the second trimester because the distal right arm and hand could not be seen by ultrasound and were presumed to be absent. Pathologic evaluation showed distal transverse shortening, tapering to a point in the mid-forearm. Five primitive digital nubbins were present, located just proximal to the tapered point. The arm vessels appeared normal histologically, and the amnion showed no evidence of intrauterine disruption. Histologic examination of the nubbins revealed osteocartilaginous tissue, never described previously within digital nubbins. This fetus has the rare phenotype of terminal transverse limb defects with residual nubbins, but differs in that the nubbins are not at the tip of the terminal transverse limb defect.  相似文献   
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