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21.
OBJECTIVE: To help the clinician bridge the gap between research and practice in determining ways to minimize side effects of endotracheal suctioning. DATA SOURCES: This article summarizes four previous reviews of research and studies published between 1984 and 1991 related to oxygenation techniques before, during and after endotracheal suctioning, and hemodynamic consequences of the suctioning procedure. STUDY SELECTION: Studies were reviewed by type of subject: animals, human subjects with normal lung function, and human subjects with abnormal lung function. Research of pediatric and head-injured populations was excluded from this review. DATA EXTRACTION: Oxygenation protocol, endotracheal suction characteristics, outcomes and measurement times, sample and setting, and findings were presented. CONCLUSIONS: Conclusions relate to the effectiveness of various endotracheal suction protocols on prevention of hypoxemia and hemodynamic compromise in intubated patients. DATA SYNTHESIS: An algorithm to guide clinical decision making is presented based on the conclusions of this review of the research. 相似文献
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Dr. Beck Walter 《Virchows Archiv : an international journal of pathology》1939,305(2):521-530
Ohne Zusammenfassung 相似文献
25.
In a prospective outcome study, 76 of 116 patients were examined 1 year after reduction and internal fixation of a dislocated humeral head fracture with an antegrade straight intramedullary nailing system using angular and sliding stable interlocking screws. Of these patients, 77% had three- or four-segment fractures according to the Neer classification. The mean absolute Constant-Murley score 1 year after trauma was 70.0±19.7 points. During the observation period, 51 complications occurred in 44 of 76 patients; of these 44 patients, only 27 required therapeutic interventions. The highest frequency of complications was apparent in those with Neer IV fractures (73.7%), while those with Neer III and Neer IV/III fractures had complication rates of 50% and 52.5%, respectively. Patients without complications showed good or excellent functional results, ranging from 78% to 96% (relative Constant-Murley score of the contralateral noninjured side). In patients with complications, the relative Constant-Murley score ranged from 51% to 65%. Despite the high complication rate, the antegrade angular and sliding stable interlocking nail can be considered effective for treating dislocated humeral head fractures. Modifications of the surgical technique for stabilizing the tubercles (additional suture cerclage fixation of fragmented tubercles) and a polyetheretherketone (PEEK) insert in the proximal segment of the nail to prevent the fixation screws from backing out can substantially decrease some of the most frequent complications. 相似文献
26.
Michelle K Nurzenski N Kathryn Briffa Roger I Price Benjamin C C Khoo Amanda Devine Thomas J Beck Richard L Prince 《Journal of bone and mineral research》2007,22(3):416-424
A population-based study on 1008 postmenopausal women identified that the 24% of women achieving high levels of PA and CI had 3.4-4.4% higher femoral bone strength in axial compression and 1.7-5.2% in bending than those achieving low levels, indicating that lifestyle factors influence bone strength in the proximal femur. INTRODUCTION: Extensive research has shown that increased physical activity (PA) and calcium intake (CI) decrease the rate of bone loss; however, there is little research on how these lifestyle variables affect bone geometry. This study was designed to investigate the effects of modifiable lifestyle variables, habitual PA and dietary CI, on femoral geometry in older women. MATERIALS AND METHODS: Femoral geometry, habitual PA, and dietary CI were measured in a population-based sample of 1008 women (median age+/-interquartile range, 75+/-4years) enrolled in a randomized controlled trial (RCT) of calcium supplementation. Baseline PA and CI were assessed by validated questionnaires, and 1-year DXA scans (Hologic 4500A) were analyzed using the hip structural analysis technique. Section modulus (Z), an index of bending strength, cross-sectional area (CSA), an index of axial compression strength, subperiosteal width (SPW), and centroid position, the position of the center of mass, were measured at the femoral neck (NN), intertrochanter (IT), and femoral shaft (FS) sites. These data were divided into tertiles of PA and CI, and the results were compared using analysis of covariance (ANCOVA), with corrections for age, height, weight, and treatment (calcium/placebo). RESULTS AND CONCLUSIONS: PA showed a significant dose-response effect on CSA all hip sites (p<0.03) and Z at the narrow neck and intertrochanter sites (p<0.02). For CI, there was a dose-response effect for centroid position at the intertrochanter (p=0.03). These effects were additive, such that the women (n=240) with PA in excess of 65.5 kcal/day and CI in excess of 1039 mg/day had significantly greater CSA (NN, 4.4%; IT, 4.3%; FS, 3.4%) and Z (NN, 3.9%; IT, 5.2%). These data show a favorable association between PA and aspects of bone structural geometry consistent with better bone strength. Association between CI and bone structure was only evident in 1 of 15 variables tested. However, there was evidence that there may be additive effects, whereby women with high levels of PA and CI in excess of 1039 mg/day had significantly greater CSA (NN, 0.4%; FS, 2.1%) and Z (IT, 3.0%) than women with high PA but low CI. These data show that current public health guidelines for PA and dietary CI are not inappropriate where bone structure is the health component of interest. 相似文献
27.
Moh H Malek Dale E Berger William D Marelich Jared W Coburn Travis W Beck Terry J Housh 《European journal of cardio-thoracic surgery》2006,30(4):637-643
The purpose of this study was to use a meta-analytical technique to examine the efficacy of surgical repair of pectus excavatum on pulmonary function. Studies were retrieved via computerized literature searches, cross-referencing from original and review articles. Inclusion criteria were as follows: (1) reporting quantitative measures of preoperative and postoperative pulmonary function; (2) published in the English language; (3) indexed between January 1960 and September 2005; (4) reporting the duration between which preoperative and postoperative assessments were conducted; and (5) describing the pulmonary assessment procedures. The titles and abstracts of potentially relevant articles were reviewed to determine whether they met the criteria for inclusion. Twelve studies representing 313 pectus excavatum patients met the inclusion criteria and were used for the meta-analysis. Random-effects modeling yielded a mean weighted effect size (ES) for pulmonary function which was statistically nonsignificant (ES=0.08, 95% CI=-0.20 to 0.35; P=0.58). The findings of the present study indicated that surgical repair of pectus excavatum does not significantly improve pulmonary function. These findings, however, may be a result of testing pulmonary function under conditions in which pectus excavatum does not manifest itself. 相似文献
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D R Luke J E Beck K Vadiei M Yousefpour C F LeMaistre J C Yau 《Journal of clinical pharmacology》1990,30(2):163-169
The metabolic effects of intravenous cyclosporine on lipids and lipoproteins were studied in 29 allogeneic bone marrow recipients compared with 13 autologous bone marrow patients not requiring cyclosporine therapy. Patients were monitored continuously from 5 days prior to 27 days following transplantation; cyclosporine treatment was initiated 4 days before transplantation. Fasting lipid and lipoprotein levels were measured in serial blood samples throughout the study period. Nutritional supplementation, conditioning regimens and concomitant medications were not significantly different between groups. Furthermore, no significant differences in age, weight, lipid, or lipoprotein levels were found at baseline between the patient groups. Cholesterol, triglyceride, low-density lipoprotein cholesterol, and very low-density lipoprotein cholesterol levels remained unchanged in autologous patients. As compared with baseline values, plasma total cholesterol increased by an average of 26 percent in allogeneic transplantation patients receiving cyclosporine. Similarly, the ratio of low-density lipoprotein to high-density lipoprotein cholesterol was fourfold greater in those patients treated with cyclosporine compared to the autologous group. We conclude that cyclosporine appears to elevate cholesterol levels. Neither acute graft vs host disease nor changes in hepatic function could explain the differences in plasma cholesterol levels between groups. 相似文献
30.
L H Beck 《Hospital practice (Office ed.)》1988,23(8):75-81, 85-90