Karen K. Evans
MedStar Georgetown University Hospital
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Publication
Featured researches published by Karen K. Evans.
Plastic and Reconstructive Surgery | 2006
Christopher E. Attinger; Karen K. Evans; Erwin J. Bulan; Peter A. Blume; Paul R. Cooper
Background: Ian Taylor introduced the angiosome concept, separating the body into distinct three-dimensional blocks of tissue fed by source arteries. Understanding the angiosomes of the foot and ankle and the interaction among their source arteries is clinically useful in surgery of the foot and ankle, especially in the presence of peripheral vascular disease. Methods: In 50 cadaver dissections of the lower extremity, arteries were injected with methyl methacrylate in different colors and dissected. Preoperatively, each reconstructive patients vascular anatomy was routinely analyzed using a Doppler instrument and the results were evaluated. Results: There are six angiosomes of the foot and ankle originating from the three main arteries and their branches to the foot and ankle. The three branches of the posterior tibial artery each supply distinct portions of the plantar foot. The two branches of the peroneal artery supply the anterolateral portion of the ankle and rear foot. The anterior tibial artery supplies the anterior ankle, and its continuation, the dorsalis pedis artery, supplies the dorsum of the foot. Blood flow to the foot and ankle is redundant, because the three major arteries feeding the foot have multiple arterial-arterial connections. By selectively performing a Doppler examination of these connections, it is possible to quickly map the existing vascular tree and the direction of flow. Conclusions: Detailed knowledge of the vascular anatomy of the foot and ankle allows the plastic surgeon to plan vascularly sound reconstructions, the foot and ankle surgeon to design safe exposures of the underlying skeleton, and the vascular surgeon to choose the most effective revascularization for a given wound.
Plastic and Reconstructive Surgery | 2014
Paul J. Kim; Christopher E. Attinger; John S. Steinberg; Karen K. Evans; Kelly Powers; Rex W. Hung; Jesse R. Smith; Zinnia M. Rocha; Lawrence A. Lavery
Background: Negative-pressure wound therapy with instillation is a novel wound therapy that combines negative pressure with instillation of a topical solution. Methods: This retrospective, historical, cohort-control study examined the impact of negative-pressure wound therapy with and without instillation. Results: One hundred forty-two patients (negative-pressure wound therapy, n = 74; therapy with instillation, 6-minute dwell time, n = 34; and therapy with instillation, 20-minute dwell time, n = 34) were included in the analysis. Number of operative visits was significantly lower for the 6- and 20-minute dwell time groups (2.4 ± 0.9 and 2.6 ± 0.9, respectively) compared with the no-instillation group (3.0 ± 0.9) (p ⩽ 0.05). Hospital stay was significantly shorter for the 20-minute dwell time group (11.4 ± 5.1 days) compared with the no-instillation group (14.92 ± 9.23 days) (p ⩽ 0.05). Time to final surgical procedure was significantly shorter for the 6- and 20-minute dwell time groups (7.8 ± 5.2 and 7.5 ± 3.1 days, respectively) compared with the no-instillation group (9.23 ± 5.2 days) (p ⩽ 0.05). Percentage of wounds closed before discharge and culture improvement for Gram-positive bacteria was significantly higher for the 6-minute dwell time group (94 and 90 percent, respectively) compared with the no-instillation group (62 and 63 percent, respectively) (p ⩽ 0.05). Conclusion: The authors’ results suggest that negative-pressure wound therapy with instillation (6- or 20-minute dwell time) is more beneficial than standard negative-pressure wound therapy for the adjunctive treatment of acutely and chronically infected wounds that require hospital admission. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.
Journal of Diabetes and Its Complications | 2011
Karen K. Evans; Christopher E. Attinger; Ali Al-Attar; Christopher J. Salgado; Carrie K. Chu; Samir Mardini; Richard F. Neville
OBJECTIVE Limb salvage in the diabetic population is complex, controversial, costly and variable throughout the world. Within the diabetic population, the indications and morbidity surrounding major leg amputation have not been well defined. RESEARCH DESIGN AND METHODS A retrospective study of the Georgetown Limb Salvage Registry was conducted to determine outcomes in diabetic patients undergoing proximal forefoot/midfoot (PF/M) amputations and to help define the indications for major leg amputation in ambulatory diabetic patients. RESULTS Of the 937 ambulatory diabetic patients identified during this time period, 808 who presented with superficial ulcers or distal forefoot disease and who did not go on to PF/M or higher amputation were eliminated. Records of 88 patients (92 limbs) in the PF/M amputation group and 25 patients in the below the knee amputation (BKA) group were reviewed (no above knee amputations were performed). At 2 years in the PF/M amputation group, 80% (70/88) of patients were still alive, 73% (68/92) of the limbs remained intact, and 64% of patients (56/88) were ambulatory. In contrast, in the BKA population at 2 years, 52% (13/25) of patients were deceased and 64% (16/25) were ambulating with a prosthetic limb (or had been ambulating at the time of death). The only statistically significant difference between these two groups was the presence of Charcot collapse and rear-foot disease in the BKA group. CONCLUSION Aggressive efforts at salvage with PF/M amputation procedures should be entertained prior to higher level amputations due to the increased morbidity and mortality evidenced.
Plastic and Reconstructive Surgery | 2013
Paul J. Kim; Christopher E. Attinger; John S. Steinberg; Karen K. Evans; Burkhard Lehner; Christian Willy; Lawrence A. Lavery; Tom Wolvos; Dennis P. Orgill; William J. Ennis; John Lantis; Allen Gabriel; Gregory Schultz
Background: Negative-pressure wound therapy with instillation is increasingly utilized as an adjunct therapy for a wide variety of wounds. Despite its growing popularity, there is a paucity of evidence and lack of guidance to provide effective use of this therapy. Methods: A panel of experts was convened to provide guidance regarding the appropriate use of negative-pressure wound therapy with instillation. A face-to-face meeting was held where the available evidence was discussed and individual clinical experience with this therapy was shared. Follow-up communication among the panelists continued until consensus was achieved. The final consensus recommendations were derived through more than 80 percent agreement among the panelists. Results: Nine consensus statements were generated that address the appropriate use of negative-pressure wound therapy with instillation. The question of clinical effectiveness of this therapy was not directly addressed by the consensus panel. Conclusion: This document serves as preliminary guidelines until more robust evidence emerges that will support or modify these consensus recommendations.
Wound Repair and Regeneration | 2013
Michael A. Howard; Reto Asmis; Karen K. Evans; Thomas A. Mustoe
While the importance of oxygen to the wound healing process is well accepted, research and technological advances continue in this field and efforts are ongoing to further utilize oxygen as a therapeutic modality. In this paper, the authors briefly review the role of oxygen in wound healing and discuss the distinct mechanism of action as well as the advantages and disadvantages of the three major oxygen‐based therapies currently in clinical use (Hyperbaric Oxygen and Topical Oxygen and Continuous Diffusion of Oxygen), as well as review the existing literature regarding these distinct therapeutic modalities.
Seminars in Plastic Surgery | 2011
Karim Bakri; Samir Mardini; Karen K. Evans; Brian T. Carlsen; Phillip G. Arnold
Large and life-threatening thoracic cage defects can result from the treatment of traumatic injuries, tumors, infection, congenital anomalies, and radiation injury and require prompt reconstruction to restore respiratory function and soft tissue closure. Important factors for consideration are coverage with healthy tissue to heal a wound, the potential alteration in respiratory mechanics created by large extirpations or nonhealing thoracic wounds, and the need for immediate coverage for vital structures. The choice of technique depends on the size and extent of the defect, its location, and donor site availability with consideration to previous thoracic or abdominal operations. The focus of this article is specifically to describe the use of the pectoralis major, latissimus dorsi, and rectus abdominis muscle flaps for reconstruction of thoracic defects, as these are the workhorse flaps commonly used for chest wall reconstruction.
Wound Repair and Regeneration | 2013
Michael A. Howard; Reto Asmis; Karen K. Evans; Thomas A. Mustoe
While the importance of oxygen to the wound healing process is well accepted, research and technological advances continue in this field and efforts are ongoing to further utilize oxygen as a therapeutic modality. In this paper, the authors briefly review the role of oxygen in wound healing and discuss the distinct mechanism of action as well as the advantages and disadvantages of the three major oxygen‐based therapies currently in clinical use (Hyperbaric Oxygen and Topical Oxygen and Continuous Diffusion of Oxygen), as well as review the existing literature regarding these distinct therapeutic modalities.
Annals of Plastic Surgery | 2005
Karen K. Evans; Yvonne Rasko; Joanne J. Lenert; Michael Olding
Numerous studies have shown that the final stage in breast reconstruction, creation of the nipple-areolar complex, correlates highly with patient satisfaction and acceptance of body image. There are many different techniques, including nipple sharing, free-composite grafts, and local “pull-out” flaps, all of which are vulnerable to an unpredictable degree of loss of projection and possible need for reoperation. This leads to problems with symmetry and overbuilding the initial reconstruction with wider-based, larger flaps, which may cause breast-contour changes. We have used calcium hydroxylapatite (Radiesse, Bioform Inc., Franksville, WI) following nipple-areolar reconstruction to maintain or restore projection in selected breast-reconstruction patients. Approximately 0.4–1 mL of calcium hydroxylapatite was injected subdermally using a 27-gauge needle in 6 selected patients. All patients tolerated the office procedure well without the need for local anesthesia. We report initial short-term success, with 100% patient satisfaction, minimal loss of projection, and no complications. Semipermanent injectable soft-tissue fillers such as calcium hydroxylapatite may be useful in selected patients as a simple solution to the difficult problem of the lack of nipple projection following reconstruction.
Plastic and Reconstructive Surgery | 2016
Paul J. Kim; Christopher E. Attinger; Noah Oliver; Caitlin Garwood; Karen K. Evans; John S. Steinberg; Lawrence A. Lavery
Background: Negative-pressure wound therapy with instillation is an adjunctive treatment that uses periodic instillation of a solution and negative pressure for a wide diversity of wounds. A variety of solutions have been reported, with topical antiseptics as the most frequently chosen option. The objective of this study was to compare the outcomes of normal saline versus an antiseptic solution for negative-pressure wound therapy with instillation for the adjunctive treatment of infected wounds. Methods: This was a prospective, randomized, effectiveness study comparing 0.9% normal saline versus 0.1% polyhexanide plus 0.1% betaine for the adjunctive treatment of infected wounds that required hospital admission and operative débridement. One hundred twenty-three patients were eligible, with 100 patients randomized for the intention-to-treat analysis and 83 patients for the per-protocol analysis. The surrogate outcomes measured were number of operative visits, length of hospital stay, time to final surgical procedure, proportion of closed or covered wounds, and proportion of wounds that remained closed or covered at the 30-day follow-up. Results: There were no statistically significant differences in the demographic profiles in the two cohorts except for a larger proportion of male patients (p = 0.004). There was no statistically significant difference in the surrogate outcomes with the exception of the time to final surgical procedure favoring normal saline (p = 0.038). Conclusion: The authors’ results suggest that 0.9% normal saline may be as effective as an antiseptic (0.1% polyhexanide plus 0.1% betaine) for negative-pressure wound therapy with instillation for the adjunctive inpatient management of infected wounds. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, II.
Journal of Vascular Surgery | 2013
Paul J. Kim; Karen K. Evans; John S. Steinberg; Mark E. Pollard; Christopher E. Attinger
There are a growing number of wound care centers being established globally. The emergence of these centers reflects the increasing incidence and prevalence of chronic wounds as well as the cost to the health care systems these patients represent. A systematic approach to the development and implementation of a comprehensive wound care program is necessary to provide quality wound care as well as to establish a financially viable enterprise. A wound care center can take shape in various forms from small free-standing clinics to large hospital-based programs. Regardless of the physical location, the most important factor for the success of the wound care center is a strong commitment by the members of the multidisciplinary team. The capacity to effectively manage certain wounds can be limited by the absence of key specialties within the team. The physical space and financial support from the sponsoring institution are also important components. This article reviews the critical elements to building and sustaining a successful multidisciplinary wound care center.