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31.
Background. Emphasis on cost containment in coronary artery bypass surgery is becoming increasingly important in modern hospital management. The revival of interest in off-pump (beating heart) coronary artery bypass surgery may influence the economic outcome. This study examines these effects.

Methods. Two hundred patients undergoing first-time coronary artery bypass surgery were prospectively randomized to either conventional cardiopulmonary bypass and cardioplegic arrest or off-pump surgery. Variable and fixed direct costs were obtained for each group during operative and postoperative care. The data were analyzed using parametric methods.

Results. There was no difference between the groups with respect to pre- and intraoperative patient variables. Off-pump surgery was significantly less costly than conventional on-pump surgery with respect to operating materials, bed occupancy, and transfusion requirements (total mean cost per patient: on pump, $3,731.6 ± 1,169.7 vs off-pump, $2,615.13 ± 953.6; p < 0.001). Morbidity was significantly higher in the on-pump group, which was reflected in an increased cost.

Conclusions. Off-pump revascularization offers a safe, cost-effective alternative to conventional coronary revascularization with cardiopulmonary bypass and cardioplegic arrest.  相似文献   

32.
We have validated ECG-gated emission tomography using technetium-99m methoxyisobutylisonitrile for the assessment of regional ventricular function by comparing it with cine magnetic resonance imaging (MRI). Gated tomography was performed at rest in 24 patients referred for myocardial perfusion imaging [17 males and seven females with a mean age of 58 years, nine of whom had had a previous myocardial infarction (MI)]. Scores were assigned to each of nine myocardial segments for wall motion and for thickening. Cine MRI was analysed in an identical fashion. Four out of 216 (2%) segments were uninterpretable by gated tomography because of inadequate tracer uptake. In eight patients without coronary artery disease (CAD), wall motion and thickening were normal by both methods. Gated tomography showed abnormal wall motion or thickening in all patients with previous MI and in five of seven patients with CAD but no prior MI. Association between wall motion and thickening was good (r s=0.86). Overall, there was good agreement between gated tomography and MRI for both wall motion (178/212 segments, =0.66) and wall thickening (184/212 segments, =0.69). In segments with severely reduced perfusion, however, there was poorer agreement (=0.31). Interobserver and intraobserver agreement was high ( from 0.61 to 0.78). Thus, in patients investigated for CAD, there is good overall agreement between gated tomography and MRI but the agreement is lower in segments with severe perfusion defects.  相似文献   
33.
This study assesses the influence of left ventricular hypertrophy (LVH) on the accuracy of myocardial perfusion imaging using pharmacologic coronary vasodilation. Seventy-five patients without previous infarction, and with known coronary anatomy, were studied by echocardiography and PET. LVH (defined by mass greater than 131 g/m2 in males or greater than 100 g/m2 in females) was identified in 25 patients; this group did not differ significantly from the remainder in terms of clinical or angiographic parameters. Twenty patients with hypertrophy had significant coronary artery stenoses, which were identified correctly by PET in 11 (55%), in contrast to 29 of 34 patients (85%, p = 0.03) with coronary disease but normal LV mass. Normal perfusion images were obtained in three of five patients (60%) with hypertrophy but no coronary disease; in contrast, 14 of 16 patients without either coronary disease or hypertrophy (88%, p = ns) had normal scans. The accuracy of PET was 14/25 (56%) in those with hypertrophy, and 43/50 (86%, p = 0.01) in patients with normal LV mass. In this group, the presence of hypertrophy was associated with reduction in the diagnostic accuracy of PET using dipyridamole stress. These findings may account for the phenomenon of "dipyridamole nonresponsiveness" in some patients.  相似文献   
34.
BACKGROUND: We sought to investigate the effect of multiple coronary artery bypass grafting (CABG) with or without cardiopulmonary bypass (CPB) on the perioperative inflammatory response. METHODS: Sixty patients undergoing CABG were randomly assigned to one of two groups: (A) on pump with conventional CPB and cardioplegic arrest, and (B) off pump on the beating heart. Serum samples were collected for estimation of neutrophil elastase, interleukin 8 (IL-8), C3a, and C5a preoperatively and at 1, 4, 12, and 24 hours postoperatively. Furthermore, white blood cell (WBC), neutrophil, and monocyte counts were carried out preoperatively and at 1, 12, 36 and 60 hours postoperatively. Overall incidence of infection and perioperative clinical outcome were also recorded. RESULTS: The groups were similar in terms of age, weight, gender ratio, extent of coronary disease, left ventricular function, and number of grafts per patient. Neutrophil elastase concentration peaked early after CPB in the on-pump group, with a decline with time. Repeated-measures analysis of variance between groups and comparisons at each time point (modified Bonferroni) showed elastase concentrations were significantly higher in the on-pump than the off-pump group (both p < 0.0001). IL-8 increased significantly after surgery in the on-pump group, with no decline during the observation period (p = 0.01 vs off pump). C3a and C5a rose early after surgery in both groups when compared with baseline values. Postoperative WBC, neutrophil, and monocyte counts were significantly higher in the on-pump than the off-pump group (p < 0.01). Finally, the incidence of postoperative overall infections was significantly higher in the on-pump group (p < 0.0001 vs off pump). CONCLUSIONS: CABG on the beating heart is associated with a significant reduction in inflammatory response and postoperative infection when compared with conventional revascularization with CPB and cardioplegic arrest.  相似文献   
35.
INTRODUCTION: Sentinel lymph node biopsy (SLNB) has become increasingly accepted as a diagnostic method to stage the axilla in breast cancer, selecting women with a positive sentinel node for completion axillary clearance. As SLNB became established, many surgeons supplemented SLNB to sample a minimum of four lymph nodes, on the assumption that the four-node technique is supported by randomised trial data. We hypothesised that the practice of undirected sampling to supplement SLNB adds little information to the status of the residual axilla. METHODS: One hundred and sixty-five patients with early breast cancer were studied. Following successful identification of the sentinel node, 84 women had completion axillary dissection and 81 women had an axillary sample with at least four nodes available for pathological assessment. RESULTS: Following successful identification of the sentinel node in 165 patients, the false negative rate (FNR) was 2/44=4.5% (95% CI 0.6-15.5), sensitivity 42/44=95.5% (84.5-99.4) and negative predictive value (NPV) 121/123=98.4% (94.2-99.8). In the axillary dissection cohort, the FNR was 2/26=7.7% (0.9-25.1), sensitivity 24/26=92.3% (74.9-99.1) and NPV 58/60=96.7% (88.5-100). In the axillary sample group, the FNR was 0/18=0% (0-18.5), sensitivity 18/18=100% (81.5-100) and NPV 63/63=100% (94.3-100). The SLNB was the only positive node in 12/26 (46.2%) in the axillary dissection group and 10/18 (55.6%) in the axillary sampling group. There was no patient in the axillary sampling group where the sample node was positive and the sentinel node negative. CONCLUSION: Once SLNB is validated within the multidisciplinary unit, undirected sampling of the axilla following identification of the sentinel node(s) is unnecessary. The additional sampling of non-sentinel nodes has no role to play either in the assessment of a potential false negative SLNB nor as predictive information on the status of the residual axillary nodes.  相似文献   
36.
Premature infants in neonatal intensive care units (NICUs) are highly susceptible to infection due to the immaturity of their immune systems, and nosocomial infections are a significant risk factor for death and poor neurodevelopmental outcome in this population. To investigate the impact of cleaning within a NICU, a high-throughput short-amplicon-sequencing approach was used to profile bacterial and fungal surface communities before and after cleaning. Intensive cleaning of surfaces in contact with neonates decreased the total bacterial load and the percentage of Streptococcus species with similar trends for total fungal load and Staphylococcus species; this may have clinical relevance since staphylococci and streptococci are the most common causes of nosocomial NICU infections. Surfaces generally had low levels of other taxa containing species that commonly cause nosocomial infections (e.g., Enterobacteriaceae) that were not significantly altered with cleaning. Several opportunistic yeasts were detected in the NICU environment, demonstrating that these NICU surfaces represent a potential vector for spreading fungal pathogens. These results underline the importance of routine cleaning as a means of managing the microbial ecosystem of NICUs and of future opportunities to minimize exposures of vulnerable neonates to potential pathogens and to use amplicon-sequencing tools for microbial surveillance and hygienic testing in hospital environments.  相似文献   
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39.
ObjectiveTo evaluate the wound healing effect of aqueous extract of Crotalaria verrucosa (C. verrucosa) in rats.MethodsThree wound models including incision, excision and dead space wounds were used in this study. The parameters studied were breaking strength in incision models, granulation tissue dry weight, breaking strength and hydroxyproline content in dead space wounds, percentage of wound contraction and period of epithelialization in excision wound model.ResultsTwo doses of the extract with and without dexamethasone showed significant increases in mean hydroxyproline, total protein content and dry weight of granulation tissue but it was higher with dose 800 mg/kg comparing with the control. The dexamethasone treated group showed a significant (P<0.001) reduction in the wound breaking strength when compared to control group in incision type of wound model. Coadministration of C. verrucosa with dexamethasone significantly (P<0.001) increased the breaking strength compared to the dexamethasone treated only group. In excision wound model, the percentage of the wound contraction was significantly (P<0.01) increased by two doses of test extract on all the days except the lower dose which exhibited only on 12 th, 16 th days of drug treatment and it also reversed the dexamethasone suppressed wound contraction. It significantly (P <0.001) reduced the time required for epithelialization and reversed the epithelialization delaying effect of dexamethasone (P<0.001).ConclusionsC. verrucosa was found to possess significant wound healing property. This was evident by decrease in the period of epithelialization, increase in the rate of wound contraction, skin breaking strength, and granulation tissue dry weight content. Hence C. verrucosa could be a good wound healing agent.  相似文献   
40.
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