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41.

Background

Left ventricular assist devices (LVADs) have become common as a bridge to heart transplant as well as destination therapy. Acute care surgical (ACS) problems in this population are prevalent but remain ill-defined. Therefore, we reviewed our experience with ACS interventions in LVAD patients.

Methods

A total of 173 patients who received HeartMate® XVE or HeartMate® II (HMII) LVADs between December 2001 and March 2010 were studied. Patient demographics, presentation of ACS problem, operative intervention, co-morbidities, transplantation, complications, and survival were analyzed.

Results

A total of 47 (27 %) patients underwent 67 ACS procedures at a median of 38 days after device implant (interquartile range 15–110), with a peri-operative mortality rate of 5 % (N = 3). Demographics, device type, and acuity were comparable between the ACS and non-ACS groups. A total of 21 ACS procedures were performed emergently, eight were urgent, and 38 were elective. Of 29 urgent and emergent procedures, 28 were for abdominal pathology. In eight patients, the cause of the ACS problem was related to LVADs or anticoagulation. Cumulative survival estimates revealed no survival differences if patients underwent ACS procedures (p = 0.17). Among HMII patients, transplantation rates were unaffected by an ACS intervention (p = 0.2).

Conclusions

ACS problems occur frequently in LVAD patients and are not associated with adverse outcomes in HMII patients. The acute care surgeon is an integral member of a comprehensive approach to effective LVAD management.  相似文献   
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Uncertainty as to the functional role of the D(3) dopamine receptor, due primarily to a paucity of selective agonists or antagonists, is being addressed in mice with targeted gene deletion ("knockout") thereof. This study describes, for the first time, the phenotype of congenic D(3)-null mice. Initially, 129/Sv x C57BL/6 D(3)-null mice were backcrossed 14 times onto C57BL/6; they were then assessed using an ethologically based approach which resolves all topographies of behaviour within the mouse repertoire. The ethogram of D(3)-null mice, on comparison with wildtypes, was characterised by no alteration in any topography of behaviour over an initial period of exploration; subsequent assessment over several hours revealed only increased rearing among females due to delayed habituation. Low doses of the selective D(2)-like agonist RU 24213 (0.016-0.25 mg/kg) inhibited topographies of exploratory behaviour; this effect was diminished in D(3)-null mice only when investigated following prolonged habituation, and then only for certain topographies of behaviour, primarily sniffing and rearing. High doses of RU 24213 (0.1-12.5 mg/kg) induced stereotyped sniffing and "ponderous" locomotion, while the selective D(1)-like agonist SK&F 83959 (0.016-2.0 mg/kg) promoted characteristic grooming syntax; these effects did not differ materially between the genotypes. When examined topographically on an essentially congenic C57BL/6 background (<0.005% 129/Sv), the resultant phenotype indicated essential conservation of the mouse ethogram, high-dose D(2)-like stimulatory effects, and D(1)-like stimulatory effects in the absence of D(3) receptors. A role for D(3) receptors in inhibitory processes appeared topographically circumscribed and only when baseline levels of behaviour were low.  相似文献   
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Cohen I  Azaria R  Shapira J  Yigael D  Tepper R 《Cancer》2002,94(12):3101-3106
BACKGROUND: Ultrasonography has a limited value in endometrial assessment for identification of endometrial pathologies in postmenopausal tamoxifen-treated patients. METHODS: We compared the rate of endometrial pathologies and the mean +/- SD of endometrial thickness diagnosed after the first and second transvaginal ultrasonographic studies performed on 55 postmenopausal tamoxifen-treated patients with secondary endometrial thickening (Group I). This rate was also compared with 46 similar patients without secondary thickening (Group II). We also compared the mean +/- SD of endometrial thickness detected in various ultrasonographic studies, as well as various clinical features. RESULTS: A significantly higher rate of endometrial pathologies, including two cases of endometrial cancer identified in gynecologically asymptomatic patients (3.6%), was diagnosed in Group I after the second study compared with the first study (52.7% and 9.1%, respectively; P = 0.001) and compared with those diagnosed after the second study in Group II (30.4%; P = 0.03). There was a significant increase (74.7 +/- 115%) in endometrial thickness after the second study compared with the first study performed on Group I (10.7 +/- 5.53 mm and 16.59 +/- 5.53 mm, respectively; P = 0.0001) and a significant difference in endometrial thickness demonstrated in the second study performed on Groups I and II (16.59 +/- 5.53 mm and 11.4 +/- 3.91 mm, respectively; P = 0.001).There were no significant differences in the time elapsed since the diagnosis of breast carcinoma and from the beginning of tamoxifen treatment to the performance of the first ultrasonographic study as well as the time elapsed between the first and second studies performed. CONCLUSIONS: A significant increase (> 50%) in secondary endometrial thickening, measured ultrasonographically, in postmenopausal tamoxifen-treated patients, is associated with a high rate of endometrial pathologies, including endometrial cancer.  相似文献   
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Context  The sixth Joint National Committee (JNC-VI) classification system of blood pressure emphasizes both systolic blood pressure (SBP) and diastolic blood pressure (DBP) for cardiovascular disease risk assessment. Pulse pressure may also be a valuable risk assessment tool. Objective  To compare relationships of SBP, DBP, and pulse pressure, separately and jointly, with cardiovascular disease-related mortality in men. Design and Setting  Data from the Multiple Risk Factor Intervention Trial (MRFIT), which screened men aged 35 to 57 years from 1973 through 1975 at 22 US centers, was used to assess cardiovascular disease-related mortality through 1996. Participants  A total of 342 815 men without diabetes or a history of myocardial infarction were divided into 2 groups based on their age at MRFIT screening (35- to 44-year-olds and 45- to 57-year olds). Participant blood pressure levels were classified into a JNC-VI blood pressure category based on SBP and DBP (optimal, normal but not optimal, high normal, stage 1 hypertension, stage 2-3 hypertension), and pulse pressure was calculated. Main Outcome Measure  Cardiovascular disease-related mortality. Results  There were 25 721 cardiovascular disease-related deaths. Levels of SBP and DBP were more strongly related to cardiovascular disease than pulse pressure. Relationships of SBP, DBP, and pulse pressure to cardiovascular disease-related mortality varied within JNC-VI category. Concordant elevations of SBP and DBP were associated with a greater risk of cardiovascular disease-related mortality for both age groups of men. Among men aged 45 to 57 years, higher SBP and lower DBP (discordant elevations) also yielded a greater risk of cardiovascular disease-related mortality. Conclusion  In both age groups, cardiovascular disease risk assessment was improved by considering both SBP and DBP, not just SBP, DBP, or pulse pressure separately.   相似文献   
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Dyslipidemia, and inflammatory markers: high-sensitivity C-reactive protein (hs-CRP), myeloperoxidase (MPO), lipoprotein associated phospholipase A2(Lp-PLA2), and lipid peroxides (LP) are insufficient to predict the onset, extent, and prognosis of CHD. Lipoxins (LXs), resolvins, and protectins are derived from ω-3 fatty acids: eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), and ω-6 arachidonic acid in the presence of aspirin; whereas nitrolipids are formed due to the interaction between polyunsaturated fatty acids and nitric oxide (NO). LXs, resolvins, protectins, and nitrolipids are endogenous anti-inflammatory lipid molecules that inhibit production of interleukin-6 (IL-6) and tumor necrosis factor- α (TNF-α), suppress free radical generation, enhance NO generation; and accelerate tissue repair. Thus, beneficial actions of EPA/DHA and aspirin in CHD could be attributed to the formation of LXs, resolvins, protectins, and nitrolipids and suggest that their plasma levels aid in the prediction and prognosis of CHD.  相似文献   
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