Cheong J. Lee

Epidemiology of aortic aneurysm repair in the United States from 2000 to 2010

OBJECTIVE Broad application of endovascular aneurysm repair (EVAR) has led to a rapid decline in open aneurysm repair (OAR) and improved patient survival, albeit at a higher overall cost of care. The aim of this report is to evaluate national trends in the incidence of unruptured and ruptured abdominal aortic aneurysms (AAAs), their management by EVAR and OAR, and to compare overall patient characteristics and clinical outcomes between these two approaches. METHODS A retrospective analysis of the cross-sectional National Inpatient Sample (2000-2010) was used to evaluate patient characteristics and outcomes related to EVAR and OAR for unruptured and ruptured AAAs. Data were extrapolated to represent population-level statistics through the use of data from the U.S. Census Bureau. Comparisons between groups were made with the use of descriptive statistics. RESULTS There were 101,978 patients in the National Inpatient Sample affected by AAAs over the 11-year span of this study; the average age was 73 years, 21% were women, and 90% were white. Overall in-hospital mortality rate was 7%, with a median length of stay (LOS) of 5 days and median hospital charges of

Evidence for a Standardized Preadmission Showering Regimen to Achieve Maximal Antiseptic Skin Surface Concentrations of Chlorhexidine Gluconate, 4%, in Surgical Patients

58,305. In-hospital mortality rate was 13 times greater for ruptured patients, with a median LOS of 9 days and median charges of

Epidemiology of Peripheral Arterial Disease and Critical Limb Ischemia

84,744. For both unruptured and ruptured patients, EVAR was associated with a lower in-hospital mortality rate (4% vs 1% for unruptured and 41% vs 27% for ruptured; P < .001 for each), shorter median LOS (7 vs 2; 9 vs 6; P < .001) but a 27%-36% increase in hospital charges. CONCLUSIONS The overall use of EVAR has risen sharply in the past 10 years (5.2% to 74% of the total number of AAA repairs) even though the total number of AAAs remains stable at 45,000 cases per year. In-hospital mortality rates for both ruptured and unruptured cases have fallen by more than 50% during this time period. Lower mortality rates and shorter LOS despite a 27%-36% higher cost of care continues to justify the use of EVAR over OAR. For patients with suitable anatomy, EVAR should be the preferred management of both ruptured and unruptured AAAs.

Secondary interventions after elective thoracic endovascular aortic repair for degenerative aneurysms

IMPORTANCE To reduce the amount of skin surface bacteria for patients undergoing elective surgery, selective health care facilities have instituted a preadmission antiseptic skin cleansing protocol using chlorhexidine gluconate. A Cochrane Collaborative review suggests that existing data do not justify preoperative skin cleansing as a strategy to reduce surgical site infection. OBJECTIVES To develop and evaluate the efficacy of a standardized preadmission showering protocol that optimizes skin surface concentrations of chlorhexidine gluconate and to compare the findings with the design and methods of published studies on preoperative skin preparation. DESIGN, SETTING, AND PARTICIPANTS A randomized prospective analysis in 120 healthy volunteers was conducted at an academic tertiary care medical center from June 1, 2014, to September, 30, 2014. Data analysis was performed from October 13, 2014, to October 27, 2014. A standardized process of dose, duration, and timing was used to maximize antiseptic skin surface concentrations of chlorhexidine gluconate applied during preoperative showering. The volunteers were randomized to 2 chlorhexidine gluconate, 4%, showering groups (2 vs 3 showers), containing 60 participants each, and 3 subgroups (no pause, 1-minute pause, or 2-minute pause before rinsing), containing 20 participants each. Volunteers used 118 mL of chlorhexidine gluconate, 4%, for each shower. Skin surface concentrations of chlorhexidine gluconate were analyzed using colorimetric assay at 5 separate anatomic sites. Individual groups were analyzed using paired t test and analysis of variance. INTERVENTION Preadmission showers using chlorhexidine gluconate, 4%. MAIN OUTCOMES AND MEASURES The primary outcome was to develop a standardized approach for administering the preadmission shower with chlorhexidine gluconate, 4%, resulting in maximal, persistent skin antisepsis by delineating a precise dose (volume) of chlorhexidine gluconate, 4%; duration (number of showers); and timing (pause) before rinsing. RESULTS The mean (SD) composite chlorhexidine gluconate concentrations were significantly higher (P < .001) in the 1- and 2-minute pause groups compared with the no-pause group in participants taking 2 (978.8 [234.6], 1042.2 [219.9], and 265.6 [113.3] µg/mL, respectively) or 3 (1067.2 [205.6], 1017.9 [227.8], and 387.1 [217.5] µg/mL, respectively) showers. There was no significant difference in concentrations between 2 and 3 showers or between the 1- and 2-minute pauses. CONCLUSIONS AND RELEVANCE A standardized preadmission shower regimen that includes 118 mL of aqueous chlorhexidine gluconate, 4%, per shower; a minimum of 2 sequential showers; and a 1-minute pause before rinsing results in maximal skin surface (16.5 µg/cm2) concentrations of chlorhexidine gluconate that are sufficient to inhibit or kill gram-positive or gram-negative surgical wound pathogens. This showering regimen corrects deficiencies present in current nonstandardized preadmission shower protocols for patients undergoing elective surgery.

The effect of Surgical Care Improvement Project measures on national trends on surgical site infections in open vascular procedures.

With a rise in the aging popluation, the prevalence of peripheral arterial disease (PAD) is markedly increasing. The overall disease prevalence of PAD is in the range of 3%-10%, which increases to 15%-20% in persons older than 70 years of age. Given this upward trend in disease prevalence, the economic and societal burden of PAD would be considerable. The subgroup of patients who develop critical limb ischemia (CLI) represents the most challenging population to manage medically, surgically, and endovascularly. Patients with symptomatic PAD and CLI have an increased risk for death and cardiovascular events, especially in those with CLI who carry with them a substantial risk of limb loss. Advances in medical, surgical, and endovascular techniques have shown excellent outcomes in the treatment of these patients, however the optimal management paradigm has not been elucidated. This article reviews the classification and epidemiology, risk factors, natural history, and health care costs associated with PAD and CLI.

Progressive shortfall in open aneurysm experience for vascular surgery trainees with the impact of fenestrated and branched endovascular technology

OBJECTIVE We assessed the incidence and outcomes of graft-related secondary interventions (ie, open conversion or proximal or distal extensions) after elective thoracic endovascular aortic repair (TEVAR) for aneurysmal disease. METHODS An institutional review of TEVAR for descending thoracic aortic aneurysms (DTAAs), between 2000 and 2011, was performed. Only elective TEVAR for DTAA using commercially available endografts was selected. Emergent cases, nonaneurysmal aortic pathology (ie, transection, pseudoaneurysm, dissection), and cases that used physician-modified devices were excluded. The incidence of unplanned graft-related secondary interventions was examined and outcomes were analyzed. RESULTS During the study period, 83 patients underwent elective TEVAR for DTAA that met the inclusion criteria. Subsequent graft-related secondary interventions were required in eight patients (10%). The mean interval to the secondary intervention was 31.8 months. Endoleak was the most common indication. Patients who required secondary interventions were significantly younger (mean age, 58 ± 12 vs 69 ± 11 years; P < .05). Operative mortality (<30 day) was zero, with one aneurysm-related late death occurring at 2 years after the secondary intervention. Factors that predisposed the need for secondary interventions were fusiform morphology of the aneurysm (P = .05) and extent of graft coverage in the proximal landing zone <3 cm (P < .05). Size of the aneurysm treated and the type of device used were not significant factors leading to secondary intervention. CONCLUSIONS Intermediate and long-term results of elective TEVAR for DTAA demonstrate good durability, with acceptable rates of graft-related secondary interventions. Age, fusiform aneurysm morphology, and extent of proximal landing zones <3 cm were significant factors that led to subsequent secondary interventions.

Preadmission Application of 2% Chlorhexidine Gluconate (CHG): Enhancing Patient Compliance While Maximizing Skin Surface Concentrations.

OBJECTIVE The Surgical Care Improvement Project (SCIP) is a national initiative to reduce surgical complications, including postoperative surgical site infection (SSI), through protocol-driven antibiotic usage. This study aimed to determine the effect SCIP guidelines have had on in-hospital SSIs after open vascular procedures. METHODS The Nationwide Inpatient Sample (NIS) was retrospectively analyzed using International Classification of Diseases, Ninth Revision, diagnosis codes to capture SSIs in hospital patients who underwent elective carotid endarterectomy, elective open repair of an abdominal aortic aneurysm (AAA), and peripheral bypass. The pre-SCIP era was defined as 2000 to 2005 and post-SCIP was defined as 2007 to 2010. The year 2006 was excluded because this was the transition year in which the SCIP guidelines were implemented. Analysis of variance and χ(2) testing were used for statistical analysis. RESULTS The rate of SSI in the pre-SCIP era was 2.2% compared with 2.3% for carotid endarterectomy (P = .06). For peripheral bypass, both in the pre- and post-SCIP era, infection rates were 0.1% (P = .22). For open, elective AAA, the rate of infection in the post-SCIP era increased significantly to 1.4% from 1.0% in the pre-SCIP era (P < .001). Demographics and in-hospital mortality did not differ significantly between the groups. CONCLUSIONS Implementation of SCIP guidelines has made no significant effect on the incidence of in-hospital SSIs in open vascular operations; rather, an increase in SSI rates in open AAA repairs was observed. Patient-centered, bundled approaches to care, rather than current SCIP practices, may further decrease SSI rates in vascular patients undergoing open procedures.

Assessment of an innovative antimicrobial surface disinfectant in the operating room environment using adenosine triphosphate bioluminescence assay

Background: In 2014, we published a series of articles in the Journal of Vascular Surgery that detailed the decrease in volume of open aneurysm repair (OAR) completed for abdominal aortic aneurysm (AAA) by vascular surgery trainees. At that time, only data points from 2000 through 2011 were available, and reliable predictions could only be made through 2015. Lack of data on endovascular aneurysm repair (EVAR) using fenestrated (FEVAR) and branched (BrEVAR) endografts also affected our findings. Despite these limitations, our predictions for OAR completed by vascular trainees were accurate for 2012 to 2014. This report uses updated data points through 2014 in conjunction with data on FEVAR and BrEVAR obtained from industry to predict trends in OAR and how it will affect vascular surgery training through 2020. Methods: An S‐curve modified logistic function was used to model the effect of introducing new technologies (EVAR, FEVAR, BrEVAR) on the standard management of AAA with OAR starting in the year 2000, similar to the technique that we have previously described. Weighted samples and data from the United States Census Bureau were used in conjunction with volume estimates derived from the National Inpatient Sample, State Inpatient Databases, and industry sources to determine trends in OAR and EVAR. The number of cases completed at teaching hospitals was calculated using the National Inpatient Sample, and Accreditation Council for Graduate Medical Education case logs were used to forecast the number of cases completed by vascular surgery trainees through 2020. Sensitivity analysis and trend analysis were completed. Results: Approximately 45,000 AAA repairs are completed annually in the United States, but only 15% of these are now completed using OAR compared with >50% just a decade ago. Further, with the accelerating adoption of FEVAR and BrEVAR, and expanding indications for standard EVAR, our model predicts that <3000 OARs will be completed annually by 2020. Because only a subset of these cases are completed at teaching institutions, our model predicts that a vascular surgery trainee in a fellowship program will complete only one to two OARs, whereas trainees in a 0+5 program may complete two to three OARs. Conclusions: Our initial prediction in the 2014 report was that vascular trainees would complete approximately five OARs by 2020. After incorporating new data on BrEVAR, FEVAR, and the accelerating pace of EVAR use between 2012 and 2014, it now appears that vascular trainees will complete one to three OARs during their training.

High-Risk Anatomic Variables and Plaque Characteristics in Carotid Artery Stenting

OBJECTIVE Surgical site infections (SSIs) are responsible for significant morbidity and mortality. Preadmission skin antisepsis, while controversial, has gained acceptance as a strategy for reducing the risk of SSI. In this study, we analyze the benefit of an electronic alert system for enhancing compliance to preadmission application of 2% chlorhexidine gluconate (CHG). DESIGN, SETTING, AND PARTICIPANTS Following informed consent, 100 healthy volunteers in an academic, tertiary care medical center were randomized to 5 chlorhexidine gluconate (CHG) skin application groups: 1, 2, 3, 4, or 5 consecutive applications. Participants were further randomized into 2 subgroups: with or without electronic alert. Skin surface concentrations of CHG (μg/mL) were analyzed using a colorimetric assay at 5 separate anatomic sites. INTERVENTION Preadmission application of chlorhexidine gluconate, 2% RESULTS Mean composite skin surface CHG concentrations in volunteer participants receiving EA following 1, 2, 3, 4, and 5 applications were 1,040.5, 1,334.4, 1,278.2, 1,643.9, and 1,803.1 µg/mL, respectively, while composite skin surface concentrations in the no-EA group were 913.8, 1,240.0, 1,249.8, 1,194.4, and 1,364.2 µg/mL, respectively (ANOVA, P<.001). Composite ratios (CHG concentration/minimum inhibitory concentration required to inhibit the growth of 90% of organisms [MIC90]) for 1, 2, 3, 4, or 5 applications using the 2% CHG cloth were 208.1, 266.8, 255.6, 328.8, and 360.6, respectively, representing CHG skin concentrations effective against staphylococcal surgical pathogens. The use of an electronic alert system resulted in significant increase in skin concentrations of CHG in the 4- and 5-application groups (P<.04 and P<.007, respectively). CONCLUSION The findings of this study suggest an evidence-based standardized process that includes use of an Internet-based electronic alert system to improve patient compliance while maximizing skin surface concentrations effective against MRSA and other staphylococcal surgical pathogens.

Ruptured Mycobacterial Aneurysm of the Carotid Artery

Terminal cleaning in the operating room is a critical step in preventing the transmission of health care-associated pathogens. The persistent disinfectant activity of a novel isopropyl alcohol/organofunctional silane solution (ISO) was evaluated in 4 operating rooms after terminal cleaning. Adenosine triphosphate bioluminescence documented a significant difference (P < .048) in surface bioburden on IOS-treated surfaces versus controls. RODAC plate cultures revealed a significant (P < .001) reduction in microbial contamination on IOS-treated surfaces compared with controls. Further studies are warranted to validate the persistent disinfectant activity of ISO within selective health care settings.