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51.
Introduction
and aim. Poor functional status is associated with increased mortality in cirrhosis patients awaiting liver transplantation (LT); however, the optimal assessment of functional status remains unknown. This study sought to determine the relationship between 6-minute walk distance (6MWD) and Karnofsky Performance Status (KPS) and their association with waitlist mortality in LT candidates.Material and methods
Two hundred seventy-eight consecutive patients listed for LT were included. KPS and 6MWD were assessed at the time of evaluation. KPS was recorded as a percentage from 0 to 100, with 0 representing death and 100 representing no presence of disease. Patients were followed from time of listing until transplantation, death, removal from the waitlist or end of the study period.Results
The mean KPS and 6MWD were 77.4 ± 13.5 and 323.6 ± 163.9 m, respectively. A mild correlation between 6MWD and KPS was demonstrated (Spearman ρ = 0.4317, P < .0001). KPS was significantly lower in patients with 6MWD < 250 meters (P < .0001). The 6MWD was significantly lower in patients who suffered waitlist mortality (266.1 vs 331.8 m, P = .05).Conclusion
In conclusion, 6MWD is a better predictor of waitlist mortality than KPS score in candidates for LT. The addition of 6MWD as a standard assessment may help to identify patients at risk of dying on the waitlist. 相似文献52.
Fenton H. McCarthy Sreekanth Vemulapalli Zhuokai Li Vinod Thourani Roland A. Matsouaka Nimesh D. Desai Ajay Kirtane Saif Anwaruddin Matthew L. Williams Jay Giri Prashanth Vallabhajosyula Robert H. Li Howard C. Herrmann Joseph E. Bavaria Wilson Y. Szeto 《The Annals of thoracic surgery》2018,105(4):1121-1128
53.
54.
55.
Gina L. Griffith Barbara Wirostko Hee-Kyoung Lee Lauren E. Cornell Jennifer S. McDaniel David O. Zamora Anthony J. Johnson 《Burns : journal of the International Society for Burn Injuries》2018,44(5):1179-1186
Purpose
The study objective was to test the utilization of a crosslinked, thiolated hyaluronic acid (CMHA-S) film for treating corneal chemical burns.Methods
Burns 5.5 mm in diameter were created on 10 anesthetized, male New Zealand white rabbits by placing a 1N NaOH soaked circular filter paper onto the cornea for 30 s. Wounds were immediately rinsed with balanced salt solution (BSS). CMHA-S films were placed in the left inferior fornix of five injured and five uninjured animals. Five animals received no treatment. At 0 h, 48 h, 96 h, and on day 14 post chemical burn creation, eyes were evaluated by white light imaging, fluorescein staining, and optical coherence tomography (OCT). Corneal histology was performed using H&E and Masson's Trichrome stains.Results
Image analysis indicated biocompatible CMHA-S treatment resulted in significant decreases in the areas of corneal opacity at 48 h, 96 h, and on day 14 postoperatively. A significant increase in re-epithelialization was seen 14 days post injury. CMHA-S treated corneas showed significantly less edema than untreated burns. No pathological differences were observed in corneal histological samples as a result of CMHA-S treatment.Conclusions
CMHA-S films facilitate re-epithelialization and decrease the area of corneal opacity in our corneal alkali burn rabbit model. 相似文献56.
Jonathan L. Eliason Dawn M. Coleman Adam Gumushian James C. Stanley 《Journal of vascular surgery》2018,67(4):1207-1216
Objective
Chronic lower extremity ischemia in pediatric patients is uncommon. The intent of this study was to better define the arterial reconstructive options and their long-term durability in preadolescent and adolescent children having clinically relevant arterial occlusions affecting the lower extremity.Methods
The medical records of 33 consecutive pediatric patients who underwent lower extremity revascularization for chronic ischemia at the University of Michigan from 1974 to 2016 were reviewed. Patients were categorized by age, clinical manifestation, surgical intervention undertaken, and outcomes.Results
Operative treatments involved 26 preadolescent children (mean age, 6.1 years; range, 3-9 years) and 7 adolescent children (mean age, 13.9 years; range, 10-17 years). Occlusions were due to earlier injury related to catheter (14), cannula (2), or both catheter and cannula (14); penetrating trauma (2); and vasculitis (1). Preoperative manifestations included symptomatic extremity ischemia (25), growth retardation manifested by documented limb length discrepancies (21), and scoliosis (5). Primary arterial reconstructions were delayed after the precipitating vascular event an average of 5.3 and 11.2 years in the preadolescent and adolescent children, respectively. Primary procedures involved revascularizations of 36 extremities (in preadolescents and adolescents) including autologous vein (26/5), polyethylene terephthalate (Dacron; 1/0), and expanded polytetrafluoroethylene (0/3) bypasses and vein patch angioplasty (0/1). Vein grafts traversing the abdominal cavity (15) were wrapped with a synthetic mesh. Excluding one early graft occlusion, there were no major early postoperative complications after the primary procedures. Secondary operations followed 31% of the primary operations, being performed an average of 8.8 and 6.7 years later (in 8 preadolescent and 3 adolescent children, respectively) for late graft occlusions (6), graft stenoses (3), aneurysmal vein grafts (2), and anastomotic pseudoaneurysm (1). The unassisted primary graft patency rate was 69%, and the assisted secondary graft patency rate was 94%. Symptomatic ischemia resolved in all but two children. Mean postoperative ankle-brachial indices improved to 1.08 from 0.76 preoperatively. Among children having postoperative documentation of limb lengths, the limb length discrepancies became less (11), were unchanged (1), or progressed (3). Follow-up averaged 8.0 years. There was no operative mortality in this experience.Conclusions
Primary lower extremity arterial reconstructions in children with chronic lower extremity ischemia can be successfully undertaken with excellent results. Nevertheless, the potential for late primary graft failures, evident in nearly a third of this experience, mandates careful long-term follow-up and may necessitate secondary interventions to maintain satisfactory outcomes. 相似文献57.
Palma M. Shaw Venita Chandra Guillermo A. Escobar Nicholas Robbins Vincent Rowe Robyn Macsata 《Journal of vascular surgery》2018,67(3):960-969
Objective
Hispanics account for approximately 17% of the U.S. population. They are one of the fastest growing racial/ethnic groups, second only to Asians. This heterogeneous population has diverse socioeconomic conditions, making the prevention, diagnosis, and management of vascular disease difficult. This paper discusses the cultural, racial, and social aspects of the Hispanic community in the United States and assesses how they affect vascular disease within this population. Furthermore, it explores risk factors, medical and surgical treatments, and outcomes of vascular disease in the Hispanic population; generational evolution of these conditions; and the phenomenon called the Hispanic paradox.Methods
A systematic search of the literature was performed to identify all English-language publications from 1991 to 2014 using PubMed, which draws from the National Institutes of Health and U.S. National Library of Medicine, with the words “cardiovascular disease,” “prevalence,” “vascular,” and “Hispanic.” An additional search was performed using “cardiovascular disease and Mexico,” “cardiovascular disease and Cuba,” “cardiovascular disease and Puerto Rico,” and “cardiovascular disease and Latin America” as well as for complications, management, outcomes, surgery, vascular disease, and Hispanic paradox. The resulting publications were queried for generational data (spanning multiple well-defined age groups) regarding cardiovascular disease, and cross-references were obtained from their bibliographies. Results are segmented by country of origin.Results
Compared with non-Hispanic whites, Hispanics face higher risks of cardiovascular diseases because of a high prevalence of high blood pressure, obesity, diabetes mellitus, and ischemic stroke. However, the incidence of peripheral arterial disease and carotid disease appears to be significantly lower than in whites. The Hispanic paradox (lower mortality in spite of higher cardiovascular risk factors) may relate to challenges in ascribing life expectancy and cause of death in this diverse population. Low socioeconomic status and high prevalence of concomitant diseases negatively influence the outcomes of all patients, independent of being Hispanic.Conclusions
Understanding the cultural diversity in Hispanics is important in terms of targeting preventive measures to modify cardiovascular risk factors, which affect development and outcomes of vascular disease. The available literature regarding vascular disease in the Hispanic population is limited, and further longitudinal study is warranted to improve health care delivery and outcomes in this group. 相似文献58.
Amir A. Ghaffarian Claire L. Griffin Larry W. Kraiss Mark R. Sarfati Benjamin S. Brooke 《Journal of vascular surgery》2018,67(2):529-535.e1
Objective
Basilic vein transposition (BVT) fistulas may be performed as either a one-stage or two-stage operation, although there is debate as to which technique is superior. This study was designed to evaluate the comparative clinical efficacy and cost-effectiveness of one-stage vs two-stage BVT.Methods
We identified all patients at a single large academic hospital who had undergone creation of either a one-stage or two-stage BVT between January 2007 and January 2015. Data evaluated included patient demographics, comorbidities, medication use, reasons for abandonment, and interventions performed to maintain patency. Costs were derived from the literature, and effectiveness was expressed in quality-adjusted life-years (QALYs). We analyzed primary and secondary functional patency outcomes as well as survival during follow-up between one-stage and two-stage BVT procedures using multivariate Cox proportional hazards models and Kaplan-Meier analysis with log-rank tests. The incremental cost-effectiveness ratio was used to determine cost savings.Results
We identified 131 patients in whom 57 (44%) one-stage BVT and 74 (56%) two-stage BVT fistulas were created among 8 different vascular surgeons during the study period that each performed both procedures. There was no significant difference in the mean age, male gender, white race, diabetes, coronary disease, or medication profile among patients undergoing one- vs two-stage BVT. After fistula transposition, the median follow-up time was 8.3 months (interquartile range, 3-21 months). Primary patency rates of one-stage BVT were 56% at 12-month follow-up, whereas primary patency rates of two-stage BVT were 72% at 12-month follow-up. Patients undergoing two-stage BVT also had significantly higher rates of secondary functional patency at 12 months (57% for one-stage BVT vs 80% for two-stage BVT) and 24 months (44% for one-stage BVT vs 73% for two-stage BVT) of follow-up (P < .001 using log-rank test). However, there was no significant difference between groups in use of interventions (58% for one-stage BVT vs 51% for two-stage BVT; P = .5) to maintain patency. These findings were confirmed in multivariate analysis, in which two-stage BVTs were associated with a significantly lower rate of failure (hazard ratio, 0.39; 95% confidence interval, 0.2-0.8; P < .05) than one-stage BVTs after controlling for confounding variables. Finally, the two-stage BVT was more cost-effective (3.74 QALYs for two-stage BVT vs 3.32 QALYs for one-stage BVT) during 5 years, with an incremental cost-effectiveness ratio of $4681 per QALY.Conclusions
Our data show that two-stage BVTs are more durable and cost-effective than one-stage procedures, with significantly higher patency and lower rates of failure among comparable risk-stratified patients. These findings suggest that additional upfront costs and resources associated with creating two-stage BVTs are justified by their long-term outcomes. 相似文献59.
Hillary B. Alberta Toshio Takayama Annalise Panthofer Richard P. Cambria Mark A. Farber William D. Jordan Jon S. Matsumura 《Journal of vascular surgery》2018,67(2):382-388
Objective
We evaluated images of patients undergoing a thoracic endovascular aortic repair procedure using two reference points as a means for differentiating stent graft migration from aortic elongation. Conventional standards define migration of a stent graft as an absolute change in the distance from the distal graft ring to a distal landmark ≥10 mm compared with a baseline measurement. Aortic elongation occurs over time in both healthy individuals and patients with aortic disease. Aortic elongation in patients with stent grafts may result in increased distal thoracic aortic lengths over time. False-positive stent graft migration would be defined when these patients meet the standard definition for migration, even if the stent has not moved in relation to the elongating aorta.Methods
This retrospective study evaluated the aortic length of 23 patients treated with the conformable GORE TAG thoracic endoprosthesis (W. L. Gore & Associates, Flagstaff, Ariz) in three clinical trials (dissection, traumatic injury, and aneurysm). Patients who met the standard definition for migration were selected. A standardized protocol was used to measure aortic centerline lengths, including the innominate artery (IA) to the most distal device ring, the IA to the celiac artery (CA), and the distal ring to the CA. Baseline lengths obtained from the first postoperative image were compared with length measurements obtained from the first interval at which they met the standard definition for migration. The conventional standards for migration using a single reference point were compared with the use of dual reference points.Results
Of the 23 patients with endograft changes, 20 were deemed to have aortic elongation rather than true migration. The remaining three patients were deemed to have migration on the basis of the IA to distal ring position compared with the IA to CA length change. The IA to CA interval length change was markedly greater in those with elongation compared with migration (23.8 ± 8.4 mm vs ?3.5 ± 5.4 mm, respectively; P < .05). The distal ring to CA interval length change was greater in patients showing elongation rather than migration (18.5 ± 6.6 mm vs ?9.8 ± 5.4 mm, respectively; P < .05). The distance between the IA and distal ring was similar for elongation and migration.Conclusions
These results highlight the dynamic changes that can occur in the aorta as a natural consequence of age. Employing two landmarks can account for these changes and proves to be an important factor, among others, in the differentiation of aortic elongation from true stent graft migration. 相似文献60.