Sapan S. Desai

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

Predicted shortfall in open aneurysm experience for vascular surgery trainees

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

The effect of hospital factors on mortality rates after abdominal aortic aneurysm repair

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.

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

OBJECTIVE Since the introduction of endovascular aneurysm repair (EVAR), the volume of open aneurysm repair (OAR) has steadily declined since 2000. The introduction of next-generation devices and branched and fenestrated endograft technology continues to increase the anatomic applicability of EVAR, further decreasing the need for OAR. This study models the decline in OAR and uses historical trends to forecast future decline in volume and its potential effect on vascular surgery training. METHODS An S-curve modified logistic function was used to model the effect of introducing a new technology (EVAR) on the standard management of abdominal aortic aneurysm (AAA) with OAR starting in the year 2000, when an International Classification of Diseases, Ninth Revision, code was first introduced for EVAR. Patients who underwent EVAR and OAR for AAA were determined using the Nationwide Inpatient Sample from 1998 to 2011. Weighted samples and data from the United States Census Bureau were used to extrapolate these numbers to estimate population statistics. The number of cases completed at teaching hospitals was calculated using the Nationwide Inpatient Sample, and Accreditation Council for Graduate Medical Education case logs were used to forecast the number of cases completed by vascular surgery trainees. RESULTS The highest number of OAR cases in this study was 42,872 in 2000 compared with just 10,039 in 2011. This was mirrored by a rise in EVAR from 2358 cases in 2000 (5.2%) to 35,028 in 2011 (76.5% by volume). Of the OAR volume in 2011, 6055 cases (60.3%) were completed at teaching institutions. An S-curve model with a correlation coefficient of R2 = 0.982 predicted 3809 open AAA cases at teaching hospitals by 2015, 2162 by 2020, and 1231 by 2025. When compared with the 2011 Accreditation Council for Graduate Medical Education National Resident Report, vascular surgery residents had 44.4% utilization with regard to OAR (2690 cases covered of 6055 total). When combined with the increase in vascular surgery trainees and lower number of open repairs, vascular fellows will complete about 10 OAR cases in 2015 and five OAR cases in 2020. CONCLUSIONS The decreasing number of OAR cases will limit exposure for vascular trainees, who may be ill equipped to treat patients who require open repair beyond 2015. Additional methods for providing OAR training should be explored.

National Trends in the Adoption of Laparoscopic Cholecystectomy over 7 Years in the United States and Impact of Laparoscopic Approaches Stratified by Age

BACKGROUND Patient factors that contribute to mortality from abdominal aortic aneurysm (AAA) repair have been previously described, but few studies have delineated the hospital factors that may be associated with an increase in patient mortality after AAA. This study used a large national database to identify hospital factors that affect mortality rates after open repair (OAR) and endovascular AAA repair (EVAR) of elective and ruptured AAA. METHODS A retrospective analysis was completed using the Nationwide Inpatient Sample from 1998 to 2011. International Classification of Disease, Ninth Revision codes were used to identify patients who underwent elective or ruptured AAA repair by OAR or EVAR. The association between mortality and hospital covariates, including ownership, bed size, region, and individual hospital volume for these patients was statistically delineated by analysis of variance, χ(2), and Mann-Kendall trend analysis. RESULTS A total of 128,232 patients were identified over the 14-year period, of which 88.5% were elective procedures and 11.5% were performed acutely for rupture. Most hospitals that complete elective OAR do between one and 50 cases, with mortality between 0% and 40%. Hospitals with mortality >40% uniformly complete fewer than five elective OAR cases annually and fall in the bottom 2.5% of all hospitals for mortality. Most hospitals that complete elective EVAR do between one and 70 cases, with mortality between 0% and 13%. Hospitals with mortality >13% uniformly complete fewer than eight elective EVAR cases annually and fall in the bottom 2.5% of all hospitals for mortality. The majority of hospitals that complete OAR or EVAR for ruptured AAA have between 0% to 100% for mortality, indicative of the high mortality risk associated with rupture. CONCLUSIONS Hospitals that complete fewer than five OARs or eight EVARs annually have significantly greater mortality compared with their counterparts. Improved implementation of best practices, more detailed informed consent to include hospital mortality data, and better regional access to health care may improve survival after elective AAA repair.

Comparison of military and civilian popliteal artery trauma outcomes

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.

Outcomes of surgical paraclavicular thoracic outlet decompression

Introduction. The aim of this study was to characterize national trends in adoption of laparoscopic cholecystectomy and determine differences in outcome based on type of surgery and patient age. Methods. Retrospective cross-sectional study of patients undergoing cholecystectomy. Trends in open versus laparoscopic cholecystectomy by age group and year were analyzed. Differences in outcomes including in-hospital mortality, complications, discharge disposition, length of stay (LOS), and cost are examined. Results. Between 1999 and 2006, 358,091 patients underwent cholecystectomy. In 1999, patients aged ≥80 years had the lowest rates of laparoscopic cholecystectomy, followed by those aged 65–79, 64–50, and 49–18 years (59.7%, 65.3%, 73.2%, and 83.5%, resp., P < 0.05). Laparoscopic cholecystectomy was associated with improved clinical and economic outcomes across all age groups. Over the study period, there was a gradual increase in laparoscopic cholecystectomy performed among all age groups during each year, though elderly patients continued to lag significantly behind their younger counterparts in rates of laparoscopic cholecystectomy. Conclusion. This is the largest study to report trends in adoption of laparoscopic cholecystectomy in the US in patients stratified by age. Elderly patients are more likely to undergo open cholecystectomy. Laparoscopic cholecystectomy is associated with improved clinical outcomes.

Recent Developments in Antithrombotic Therapy: Will Sodium Warfarin Be a Drug of the Past?

OBJECTIVE Popliteal artery injury has historically led to high amputation rates in both the military and civilian setting. Military and civilian popliteal injury patterns differ in mechanism and severity of injury, prompting us to compare modern management and report differences in outcomes between these two patient groups. We hypothesized that whereas amputation rates may be higher in the military, this would correlate with worse overall injury severity. METHODS Military casualties from 2003-2007 with a popliteal artery injury identified from the Joint Theater Trauma Registry were compared retrospectively with civilian patients presenting to a single level I institution from 2002-2009 with popliteal arterial injury. Demographics, mechanism of injury, coinjuries, Injury Severity Score (ISS), Mangled Extremity Severity Scores (MESS), interventions, and secondary amputation rates were reviewed. Descriptive statistics and unpaired t-tests were used to compare data. Statistical significance was P < .05. RESULTS The study group of 110 patients consisted of 46 (41.8%) military and 64 (58.2%) civilians with 48 and 64 popliteal artery injuries, respectively. The military population was younger (28 vs 35 years; P < .004), entirely male (46 [100%] vs 51 [80%]; P < .0001), and had more penetrating injuries (44 [96%] vs 19 [30%]; P < .0001). ISS (18.7 vs 13.9; P < .005) and MESS (7.3 vs 5.1; P < .0001) were higher in the military group. Limb revascularizations in both military and civilian populations were mostly by autogenous bypass (65% vs 77%) followed by primary repair (26% vs 16%), covered stent (0% vs 6%), or other procedure (ligation and/or thrombectomy) (9% vs 1%). Fasciotomy (20 [42%] vs 37 [58%]; P = .14), compartment syndrome (10 [21%] vs 15 [23%]; P = .84), and concomitant venous repair rates (14 [29%] vs 15 [23%]; P = .42) were not different between cohorts. There was no difference in the fracture rate (26 [54%] vs 41 [64%]; P = .43), but the civilian group had a higher rate of dislocation (1 [2%] vs 19 [30%]; P < .0001). Secondary amputation rates were significantly higher in the military (14 [29%] vs 8 [13%]; P < .03). CONCLUSIONS Although both civilian and military cohorts have high amputation rates for popliteal arterial injury, the rate of amputation appears to be higher in the military and is associated with a penetrating mechanism of injury primarily from improvised explosive devices resulting in a higher MESS and ISS.

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

BACKGROUND Thoracic outlet syndrome (TOS) is a constellation of signs and symptoms caused by compression of the neurovascular structures in the thoracic outlet. These structures include the brachial plexus, the subclavian vein, and the subclavian artery, resulting in neurogenic (NTOS), venous (VTOS), and arterial (ATOS) types of TOS, respectively. The purpose of this study was to evaluate the outcomes of paraclavicular surgical decompression for TOS. METHODS A prospective analysis of patients who underwent surgical decompression for TOS at a newly established center was performed. Diagnosis of TOS was based on clinical history, a physical examination, and additional diagnostic studies. The indication for surgery in patients diagnosed with NTOS was the presence of persistent symptoms after a trial of physical therapy. Primary outcomes were assessed according to Derkashs classification as excellent, good, fair, and poor. Secondary outcomes included mortality, complications, and duration of hospital stay. RESULTS Between August 2004 and June 2011, 40 paraclavicular decompression procedures were performed on 36 patients (16 men) with TOS. The mean age was 36.5 years (range: 15-68). Bilateral decompression was performed on 4 patients. The types were NTOS (n = 19; 48%), VTOS (n = 16; 40%), and ATOS (n = 5; 12%). In addition to pain, the most common presenting symptom was numbness in NTOS, swelling in VTOS, and coolness in ATOS. A history of trauma was present in 22.2%. Two patients suffered from recurrent symptoms after previous transaxillary first rib resection for VTOS at another institution. Diagnostic tests performed included nerve conduction studies (43%), venogram (40%), and arteriogram (20%). All patients underwent paraclavicular decompression, which included radical anterior and partial middle scalenectomy, brachial plexus neurolysis, and first rib resection. The first rib resection was partial, through a supraclavicular only approach in NTOS and ATOS patients (60%) or complete, through a supra- and infraclavicular approach for VTOS patients (40%). Functional outcomes were excellent, good, fair, and poor in 74.4%, 15.4%, 10.3%, and 0% of cases, respectively. One patient was lost to follow-up. Two patients with incomplete relief of symptoms after paraclavicular decompression for NTOS underwent pectoralis minor decompression. There were no deaths. Complications included pleural effusion requiring evacuation (n = 4), neuropraxia (n = 1), and lymph leak (n = 1) treated with tube thoracostomy. No patients experienced injury to the long thoracic or phrenic nerves. The mean duration of hospital stay was 4.4 days. The mean follow-up was 10.3 months. CONCLUSIONS In our experience, surgical paraclavicular decompression can provide safe and effective relief of NTOS, VTOS, and ATOS symptoms. Functional outcomes were excellent or good in the majority of patients, with minimal complications.

Development of a scoring system to estimate mortality in abdominal aortic aneurysms management

Warfarin and heparin have formed the mainstay in the prophylaxis of deep vein thrombosis (DVT), stroke prevention in atrial fibrillation, and treatment of thromboembolic disease (TED). However, these choices are hampered by difficult administration, interactions with other medications, side effect profile, and limited indications for treatment. Anti-factor Xa (anti-Xa) inhibitors have already entered the drug market with the drug Fondaparinux being the first anti-Xa inhibitor to be approved for use in the U.S. by the Food and Drug Administration (FDA), and other drugs such as idraparinux being currently in development. A new class of medications, known as direct thrombin inhibitors (DTI), includes the parental agents lepirudin, argatroban and bivalirudin which have been approved by the FDA and the oral agents ximelagatran, melagatran and dabigatran. The latter three drugs which are oral DTIs may soon replace warfarin and heparin as the preferred medications for DVT prophylaxis and for reducing the relative risk of stroke. These drugs do not rely on blocking serine proteases nor do they require a co-factor (antithrombin III) like unfractionated heparin (UFH) or low molecular weight heparin (LMWH). DTIs are rapid in onset, easy to administer, do not interact with other medications or foods, have limited side effects, and can be administered in a fixed dose. The DTI ximelagatran has already been approved in several European and Asian countries, and over a dozen randomized clinical trials have been conducted demonstrating its performance to be on par with warfarin. However, approval by the FDA in the U.S. remains pending in view of reported incidences of elevations in hepatic enzymes that are currently under evaluation. This review examines the role of DTIs in the prevention and treatment of TED and the recent patents reported in the literature.