Recruitment of actin modifiers to TrkA endosomes governs retrograde NGF signaling and survival.

The neurotrophins NGF and NT3 collaborate to support development of sympathetic neurons. Although both promote axonal extension via the TrkA receptor, only NGF activates retrograde transport of TrkA endosomes to support neuronal survival. Here, we report that actin depolymerization is essential for initiation of NGF/TrkA endosome trafficking and that a Rac1-cofilin signaling module associated with TrkA early endosomes supports their maturation to retrograde transport-competent endosomes. These actin-regulatory endosomal components are absent from NT3/TrkA endosomes, explaining the failure of NT3 to support retrograde TrkA transport and survival. The inability of NT3 to activate Rac1-GTP-cofilin signaling is likely due to the labile nature of NT3/TrkA complexes within the acidic environment of TrkA early endosomes. Thus, TrkA endosomes associate with actin-modulatory proteins to promote F-actin disassembly, enabling their maturation into transport-competent signaling endosomes. Differential control of this process explains how NGF but not NT3 supports retrograde survival of sympathetic neurons.

Claims Variability in Charges and Payments for Common Open and Endovascular Procedures.

BACKGROUND: Cost-effectiveness in healthcare is being increasingly scrutinized. Data regarding claims variability for vascular operations are lacking. Herein, we aim to describe variability in charges and payments for aortoiliac (AI) and infrainguinal (II) revascularizations. METHODS: We analyzed 2012-2014 claims data from a statewide claims database for procedures grouped by Current Procedural Terminology codes into II-open (II-O), II-endovascular (II-E), AI-open (AI-O), and AI-endovascular interventions (AI-E). We compared charges and payments in urban (≥50,000 people, UAs) versus rural areas (<50,000 people, RAs). Amounts are reported in $US as median with interquartile range. Cost-to-charge ratios (CCRs) as a measure of reimbursement were calculated as the percentage of the charges covered by the payments. Wilcoxon rank-sum tests were performed to determine significant differences. RESULTS: A total of 5,239 persons had complete claims data. There were 7,239 UA and 6,891 RA claims, and 1,057 AI claims (AI-E = 879, AI-O = 178) and 4,182 II claims (II-E = 3,012, II-0 = 1,170). Median charges were $5,357 for AI [$1,846-$27,107] and $2,955 for II [$1,484-$9,338.5] (P < 0.0001). Median plan payment was $454 for AI [$0-$1,380] and $454 for II [$54-$1,060] (P = 0.67). For AI and II, charges were significantly higher for UA than RA (AI: UA $9,875 [$2,489-$34,427], RA $3,732 [$1,450-$20,595], P < 0.0001; II: UA $3,596 [$1,700-$21,664], RA $2,534 [$1,298-$6,169], P < 0.0001). AI-E charges were higher than AI-O (AI-E $7,960 [$1,699-$32,507], AI-O $4,774 [$2,636-$7,147], P < 0.0001), but AI-O payments were higher (AI-E $424 [$0-$1,270], AI-O $869 [$164-$1,435], P = 0.0067). II-E charges were higher (II-E $2,994 [$1,552-$22,164], II-O $2,873 [$1,108-$5,345], P < 0.0001), but II-O payments were higher (II-E $427 [$50-$907], II-O $596 [$73-$1,299], P < 0.0001). CCRs were highest for II operations and UAs. CONCLUSIONS: Wide variability in claim charges and payments exists for vascular operations. AI procedures had higher charges than II, without any difference in payments. UA charged more than RA for both AI and II operations, but RA had higher payments and CCRs. Endovascular procedures had higher charges, while open procedures had higher payments. Charge differences may be related to endovascular device costs, and further research is necessary to determine the reasons behind consistent claims variability between UA and RA.

Inferior Vena Cava Filter Resulting in Perforation and Massive Retroperitoneal Hematoma Presenting as Acute Onset of Lower Extremity Weakness.

Perforation of inferior vena cava (IVC) filter struts is a common incidental finding on postoperative computed tomography (CT) scans that is not associated with bleeding or major complications. However, in rare circumstances, it can be associated with hemorrhage requiring immediate removal. We present a case of a 62-year-old man who developed abdominal pain and right lower extremity weakness 2 weeks after treatment of a pulmonary embolism with IVC filter placement and anticoagulation. A CT scan revealed a large right-sided retroperitoneal hematoma with active extravasation from the IVC filter struts that had perforated the IVC wall. He underwent a hybrid operation with endovascular retrieval of the IVC filter and concomitant IVC primary repair combined with evacuation of the hematoma, causing nerve compression. Postoperatively, he regained normal sensory and motor function. Perforation of IVC filter struts is usually asymptomatic, but in rare circumstances, it can cause hemorrhage requiring immediate removal and IVC repair. Surgical intervention is indicated in the setting of a large hematoma with nerve or vessel compression and may require a combined endovascular and open approach.

Treatment of thoracoabdominal aortic disease in patients with connective tissue disorders.

OBJECTIVE: Aneurysmal degeneration of the entire aorta is common in patients with connective tissue disorders (CTDs). Potential treatment options of these aneurysms include open repair and endovascular repair. Our objective herein was to review available evidence for different approaches to treatment of thoracoabdominal aortic disease in patients with CTDs. METHODS: We performed a systematic literature review using PubMed and referenced manuscripts on open and endovascular treatment of thoracoabdominal aortic aneurysms and dissections in patients with CTDs. RESULTS: A total of 28 studies were identified for inclusion in this review, 8 reporting on outcomes after open thoracoabdominal aortic aneurysm repair in patients with CTD, 8 on open branched graft use, and 12 on endovascular aortic repair in this population of patients. Reported outcomes were characterized by low perioperative morbidity and mortality, good branch patency, and low rate of reintervention for open repair and significant rates of endograft-related complications and substantial need for secondary endovascular interventions and open conversions for endovascular repair. CONCLUSIONS: There is a lack of high-quality evidence to support any particular approach to aortic repair in patients with CTD and a dearth of comparative data between open repair and endovascular repair. There are distinct differences in the published lengths of follow-up between the two repair approaches as well as in the prevalence of their use in an acute vs elective setting. It is evident that endovascular interventions for aortic disease in patients with CTDs are associated with many device- and aorta-related complications both in the short term and in the long term. Despite the lack of level 1 evidence, open repair currently remains the standard approach to treatment of aortic disease due to CTDs. Open branched graft repair in particular is the preferred technique. Endovascular interventions may be cautiously used in patients with CTDs in selective circumstances.

Suprageniculate Approach to Release of Popliteal Entrapment without Distal Bypass Despite Preoperative Runoff Thrombosis.

BACKGROUND: Popliteal artery entrapment syndrome is an uncommon condition in which anatomic or functional popliteal artery compression causes arterial insufficiency. We present a case of popliteal entrapment with runoff thrombosis treated with suprageniculate release of entrapment without distal bypass. RESULTS: A 15-year old boy with Klinefelter syndrome presented with right leg claudication severely limiting his activity. He had a palpable femoral pulse, but no palpable popliteal or foot pulses on the right. Noninvasive testing showed a partially thrombosed popliteal artery with an ankle-brachial index (ABI) of 0.69. Computed tomography scan revealed type III popliteal entrapment with distal thromboses and abnormal insertion of gastrocnemius muscle. Popliteal entrapment release was performed via a medial suprageniculate approach in consideration for distal bypass. The soleus was released first; intraoperative angiography showed continued popliteal compression with forced dorsiflexion. This was followed by release of the gastrocnemius and found caudal and medial to the soleus as a tight band. Repeat angiography showed cessation of popliteal artery compression with dorsiflexion. Bypass was not performed due to improvement of distal flow seen on angiography. Postoperative recovery was unremarkable. On 1-month and 9-month follow-up, he had a normal ABI and arterial duplex, was asymptomatic, and had returned to normal activities. CONCLUSIONS: We describe suprageniculate approach to popliteal release that may be useful if a distal bypass is planned. In this case, bypass was unnecessary despite the abnormal appearance of distal runoff on preoperative imaging, as the child's perfusion improved with entrapment release alone, and arterial remodeling over time resulted in normal perfusion and arterial appearance on duplex imaging.

Temporal Trends, Determinants, and Outcomes of Inpatient versus Outpatient Arteriovenous Fistula Operations.

BACKGROUND: As high healthcare costs are increasing scrutinized, a movement toward reducing patient hospital admissions and lengths of stay has emerged, particularly for operations that may be performed safely in the outpatient setting. Our aim is to describe recent temporal trends in the proportion of dialysis access procedures performed on an inpatient versus outpatient basis and to determine the effects of these changes on perioperative morbidity and mortality. METHODS: The 2005-2008 American College of Surgeons National Surgical Quality Improvement Program database was queried for all primary arteriovenous fistula (AVF) procedures using current procedural terminology codes. Changes in the proportions of inpatient versus outpatient operations performed by year, as well as the associated 30-day postoperative morbidity and mortality, were analyzed using univariable statistics and multivariable logistic regression. RESULTS: Two thousand nine hundred fifty AVF procedures were performed over the study period. Overall, 71.7% (n = 2,114) were performed on an outpatient basis. Inpatient procedures were associated with higher 30-day morbidity (10.5% vs. 4.5%) and mortality (2.8% vs. 0.7%) than outpatient procedures (both, P < 0.001). There was a significant increase in the proportion of procedures performed on an outpatient basis over time (2005: 56% vs. 2008: 75%; P < 0.001). There were no changes in postoperative morbidity or mortality for inpatient or outpatient AVF over time (P ≥ 0.36). Independent determinants of having an inpatient procedure included younger age (OR 0.99), increasing ASA class (ASA IV OR 1.56), congestive heart failure (OR 3.32), recent ascites (OR 3.25), poor functional status (OR 3.22), the presence of an open wound (OR 1.91), and recent sepsis (OR 6.06) (all, P < 0.01). Acute renal failure (OR 2.60) and current dialysis (OR 1.44) were also predictive (P < 0.001). After correcting for baseline differences between groups, the adjusted OR for both morbidity (aOR 1.93, 95% CI 1.38-2.69) and mortality (aOR 2.85, 95% CI 1.36-5.95) remained significantly higher for inpatient versus outpatient AVF. CONCLUSIONS: Dialysis access operations are increasingly being performed on an outpatient basis, with stable perioperative outcomes. Inpatient procedures are associated with worse outcomes, likely because they are reserved for patients with acute illnesses, serious comorbidities, and poor functional status. Overall, for appropriately selected patients, the movement toward performing more elective dialysis access operations on an outpatient basis is associated with acceptable outcomes.

Partnerships between podiatrists and vascular surgeons in building effective wound care centers.

This practice memo, a collaborative effort between the Young Physicians' Program of the American Podiatric Medical Association and the Young Surgeons Committee of the Society for Vascular Surgery, is intended to aid podiatrists and vascular surgeons in the early years of their respective careers, especially those involved in the care of patients with chronic wounds. During these formative years, learning how to successfully establish an interprofessional partnership is crucial to provide the best possible care to this important population of patients.

A 10-year institutional experience with open branched graft reconstruction of aortic aneurysms in connective tissue disorders versus degenerative disease.

OBJECTIVE: Aortic reconstruction for complex thoracoabdominal aortic aneurysms (TAAAs) can be challenging, especially in patients with connective tissue disorders (CTDs) in whom tissue fragility is a major concern. Branched graft reconstruction is a more complex operation compared with inclusion patch repair of the aorta but is frequently necessary in patients with CTDs or other pathologies because of anatomic reasons. We describe our institutional experience with open branched graft reconstruction of aortic aneurysms and compare outcomes for patients with CTDs vs degenerative pathologies. METHODS: We retrospectively analyzed all patients undergoing open aortic reconstruction using branched grafts at our institution between July 2006 and December 2015. Postoperative outcomes, including perioperative morbidity and mortality, midterm graft patency, and the development of new aneurysms, were compared for patients with CTD vs degenerative disease. RESULTS: During the 10-year study period, 137 patients (CTD, 29; degenerative, 108) underwent aortic repair with branched graft reconstruction. CTD patients were significantly younger (39 ± 1.9 vs 68 ± 1.0 years; P < .001) and had fewer comorbidities (hypertension, chronic obstructive pulmonary disease, coronary artery disease; P < .05) but a higher prevalence of aortic dissections (55% vs 16%; P < .001) and aneurysms involving the thoracic aorta (90% vs 60%; P = .003) than patients with degenerative disease. Perioperative mortality (CTD: 10% [n = 3] vs degenerative: 6% [n = 6]; P = .40) and any complication (62% vs 55%; P = .47) were similar between groups. At a median follow-up time of 14.5 months (interquartile range: 6.5, 43.9 months), CTD patients were more likely to develop both new aortic (21%) and nonaortic (14%) aneurysms compared with the degenerative group (7% and 4% for aortic and nonaortic aneurysms, respectively; P = .02). Loss of branch graft patency occurred in 0 of 99 grafts (0%) in CTD patients and in 13 of 167 grafts (7.8%) in degenerative disease patients (P = .005). Loss of branch graft patency occurred most commonly in left renal artery bypass grafts (77%) and was clinically asymptomatic (creatinine: 1.77 ± 0.13 mg/dL currently vs 1.41 ± 0.25 preoperatively; P = .22). CONCLUSIONS: CTD patients with aortic aneurysms who undergo open branched graft reconstruction have reasonable outcomes compared with patients with degenerative pathology, including better branched graft patency and a similar risk of perioperative mortality and complications. Open repair of aortic aneurysms with branched graft reconstruction can be performed safely in both populations with low perioperative mortality, but ongoing surveillance is critical for the detection of new aneurysms, especially among patients with CTD.

Morbidity of endovascular abdominal aortic aneurysm repair is directly related to diameter.

OBJECTIVE: Previous randomized controlled trials have defined specific size thresholds to guide surgical decision-making in patients presenting with an abdominal aortic aneurysm (AAA). With recent advances in endovascular techniques, the anatomic considerations of AAA repair are rapidly changing. Our specific aims were to evaluate the most recent national population data to compare anatomic differences and perioperative outcomes in patients with AAA. METHODS: The American College of Surgeons National Surgical Quality Improvement Program was queried from 2011 to 2015 using the targeted vascular public use file. Patients with AAA undergoing elective open or endovascular repair were included. Risk factors and outcomes were stratified by size and divided into quartiles for categorical comparison. A logistic regression model was used to compare the impact of size on morbidity and mortality with each technique. A risk adjustment model used all preoperative criteria to generate observed and expected values for open and endovascular repair. RESULTS: There were 10,026 patients who underwent elective AAA repair, 8182 (81.6%) endovascular and 1844 (18.4%) open. Repairs were divided into density quartiles for a logistic analysis: smallest quartile, 3.5 to 5 cm; second quartile, 5.01 to 5.5 cm; third quartile, 5.51 to 6.2 cm; and largest quartile, >6.2 cm. Patients with larger aneurysms (>6.2 cm) were more likely to be male, to have a dependent functional status, and to have increased blood urea nitrogen concentration and American Society of Anesthesiologists score (P < .05). Larger aneurysms had longer operative time (162 vs 135 minutes) and greater extension toward the renal and iliac vessels (all P < .05). Risk adjustment revealed an observed/expected morbidity plot that favored endovascular repair throughout the size range but confirmed lack of size effect within the open repair category. The adjusted increase in morbidity with endovascular repair is 9.7% per centimeter increase in size of AAA. These trends remained true with an infrarenal subgroup analysis. CONCLUSIONS: Patients with a larger AAA have comorbidities and anatomic factors associated with a more difficult repair. The higher morbidity seen with larger aneurysms represents both anatomic and patient factors but seems to have a greater impact on endovascular repairs. However, endovascular repair still results in fewer near-term complications than open repair across all size strata.

Operative variables are better predictors of postdischarge infections and unplanned readmissions in vascular surgery patients than patient characteristics.

OBJECTIVE: Although postoperative readmissions are frequent in vascular surgery patients, the reasons for these readmissions are not well characterized, and effective approaches to their reduction are unknown. Our aim was to analyze the reasons for vascular surgery readmissions and to report potential areas for focused efforts aimed at readmission reduction. METHODS: The 2012 to 2013 American College of Surgeons National Quality Improvement Program (ACS NSQIP) data set was queried for vascular surgery patients. Multivariable models were developed to analyze risk factors for postdischarge infections, the major drivers of unplanned 30-day readmissions. RESULTS: We identified 86,403 vascular surgery patients for analysis. Thirty-day readmission occurred in 8827 (10%), of which 8054 (91%) were unplanned. Of the unplanned readmissions, 61% (n = 4951) were related to the index vascular surgery procedure. Infectious complications were the most common reason for a surgery-related readmission (1940 [39%]), with surgical site infection being the most common type of infection related to unplanned readmission. Multivariable analysis showed the top five preoperative risk factors for postdischarge infections were the presence of a preoperative open wound, inpatient operation, obesity, work relative value unit, and insulin-dependent diabetes (but not diabetes managed with oral medications). Cigarette smoking was a weak predictor and came in tenth in the mode (overall C index, 0.657). When operative and postoperative factors were included in the model, total operative time was the strongest predictor of postdischarge infectious complications (odds ratio [OR] 1.2 for each 1-hour increase in operative time), followed by presence of a preoperative open wound (OR, 1.5), inpatient operation (OR, 2), obesity (OR, 1.8), and discharge to rehabilitation facility (OR, 1.7; P < .001 for all). Insulin-dependent diabetes, cigarette smoking, dialysis dependence, and female gender were also predictive, albeit with smaller effects (OR, 1.1-1.3 for all; P < .001). The overall fit of the multivariable model was fair (C statistic, 0.686). CONCLUSIONS: Infectious complications dominate the reasons for unplanned 30-day readmissions in vascular surgery patients. We have identified preoperative, operative, and postoperative risk factors for these infections with the goal of reducing these complications and thus readmissions. Expected patient risk factors, such as diabetes, obesity, renal insufficiency, and cigarette smoking, were less important in predicting infectious complications compared with operative time, presence of a preoperative open wound, and inpatient operation. Our findings suggest that careful operative planning and expeditious operations may be the most effective approaches to reducing infections and thus readmissions in vascular surgery patients.

Medical therapy and intervention do not improve uncomplicated isolated mesenteric artery dissection outcomes over observation alone.

OBJECTIVE: Isolated dissection of the mesenteric vessels is rare but increasingly recognized. This study aimed to evaluate patient characteristics, primary treatment, and subsequent outcomes of mesenteric dissection using multi-institutional data. METHODS: All patients at participant hospitals between January 2003 and December 2015 with dissection of the celiac artery (or its branches) or dissection of the superior mesenteric artery (SMA) were included. Patients with an aortic dissection were excluded. Demographic, treatment, and follow-up data were collected. The primary outcomes included late vessel thrombosis (LVT) and aneurysmal degeneration (AD). RESULTS: Twelve institutions identified 227 patients (220 with complete treatment records) with a mean age of 55 ± 12.5 years. Median time to last follow up was 15 months (interquartile range, 3.8-32). Most patients were men (82% vs 18% women) and symptomatic at presentation (162 vs 65 asymptomatic). Isolated SMA dissection was more common than celiac artery dissection (n = 158 and 81, respectively). Concomitant dissection of both arteries was rare (n = 12). The mean dissection length was significantly longer in symptomatic patients than in asymptomatic patients in both the celiac artery (27 vs 18 mm; P = .01) and the SMA (64 vs 40 mm; P < .001). Primary treatment was medical in 146 patients with oral anticoagulation or antiplatelet therapy (n = 76 and 70, respectively), whereas 56 patients were observed. LVT occurred in six patients, and 16 patients developed AD (3% and 8%, respectively). For symptomatic patients without evidence of ischemia (n = 134), there was no difference in occurrence of LVT with medical therapy compared with observation alone (9% vs 0%; P = .35). No asymptomatic patient (n = 64) had an episode of LVT at 5 years. AD rates did not differ among symptomatic patients without ischemia treated with medical therapy or observed (9% vs 5%; P = .95). Surgical or endovascular intervention was performed in 18 patients (3 ischemia, 13 pain, 1 AD, 1 asymptomatic). Excluding the patients treated for ischemia, there was no difference in LVT with surgical intervention vs medical management (one vs five; P = .57). CONCLUSIONS: Asymptomatic patients with isolated mesenteric artery dissection may be observed and followed up with intermittent imaging. Symptomatic patients tend to have longer dissections than asymptomatic patients. Symptomatic isolated mesenteric artery dissection without evidence of ischemia does not require anticoagulation and may be treated with antiplatelet therapy or observation alone.

A Fourteen-Year Experience with Vascular Anomalies Encountered during Transaxillary Rib Resection for Thoracic Outlet Syndrome.

BACKGROUND: Transaxillary approach to first rib resection and scalenectomy (TAFRRS) is a well-established technique for treatment of thoracic outlet syndrome (TOS). Although anatomic features encountered during TAFRRS are in general constant, vascular anomalies may be encountered but have not been described to date. Herein we describe vascular abnormalities encountered during TAFRRS. METHODS: We performed a retrospective review of a prospective practice database of 224 operations for TOS performed in 172 patients from March 2000 to March 2014. We excluded 10 patients with missing operative reports, 3 reoperations on the same patient, and 8 non-transaxillary resections. We recorded vascular anomalies identified in operative reports and reviewed computed tomography imaging to delineate the nature of these abnormalities. RESULTS: The overall incidence of vascular anomalies was 11% (22 of 203 TAFRRS). Most patients with anomalies had venous TOS (vTOS) (9 patients, 41%), followed by 7 (32%) with neurogenic TOS (nTOS). The remainder of the patients had arterial TOS (aTOS) (6 patients, 27%). Seven patients (32%) had an abnormal subclavian artery (SCA) with 5 (23%) having an abnormal arterial course in the anterior scalene muscle (ASM); 6 patients (27%) had an abnormal internal mammary artery (IMA) originating from distal SCA; 4 (18%) had abnormalities in the supreme thoracic artery (bifurcation or duplication); 2 (9%) had an abnormal branch from the SCA with anomalous location in the operative field; and 3 (14%) had an abnormal large venous branch penetrating the ASM. In the 19 patients with arterial anomalies, 8 (42%) were recognized as arterial branches penetrating the ASM, and 11 (58%) were noticed as they had anomalous arterial locations within the operative field. Most arterial anomalies were seen in vTOS (9, 45%), followed by nTOS (7, 35%). No intraoperative vascular complications occurred. Perioperative complications included 1 occurrence of postoperative transfusion for bleeding following axillary drain discontinuation and 2 Horner's syndromes. One aberrant IMA was electively ligated to allow complete thoracic outlet decompression. CONCLUSIONS: Arterial anomalies during TAFRRS are encountered in 11% of operations, and may present with vessel locations in unusual areas within the operative field, or as abnormal vessels penetrating the ASM, thus making scalenectomy precarious. Careful attention must be paid to possible abnormal locations of vessels in the thoracic outlet to avoid bleeding complications.

Technical aspects of branched graft aortic reconstruction in patients with connective tissue disorders.

Connective tissue disorders (CTDs) predispose patients to dilation of the entire aorta, resulting in the development of extensive aneurysms. Aortic reconstruction in CTD patients can be challenging and demands specific approaches to ensure initial success and lasting stability of aortic repair. Herein, we describe technical approaches to aortic reconstruction in patients with CTDs and briefly report our outcomes on the use of branched grafts for reconstruction in this unique population of patients. We conclude that aortic reconstruction in CTD patients with branched grafts can be performed safely, with a low morbidity and mortality and excellent branch patency. Branched surgical grafts should be used preferentially over the inclusion patch technique during open repair to minimize the late development of patch aneurysms.

Drivers of readmissions in vascular surgery patients.

OBJECTIVE: Postoperative readmissions are frequent in vascular surgery patients, but it is not clear which factors are the main drivers of readmissions. Specifically, the relative contributions of patient comorbidities vs those of operative factors and postoperative complications are unknown. We sought to study the multiple potential drivers of readmission and to create a model for predicting the risk of readmission in vascular patients. METHODS: The 2012-2013 American College of Surgeons National Surgical Quality Improvement Program data set was queried for unplanned readmissions in 86,238 vascular patients. Multivariable forward selection logistic regression analysis was used to model the relative contributions of patient comorbidities, operative factors, and postoperative complications for readmission. RESULTS: The unplanned readmission rate was 9.3%. The preoperative model based on patient demographics and comorbidities predicted readmission risk with a low C index of .67; the top five predictors of readmission were American Society of Anesthesiologists class, preoperative open wound, inpatient operation, dialysis dependence, and diabetes mellitus. The postoperative model using operative factors and postoperative complications predicted readmission risk better (C index, .78); postoperative complications were the most significant predictor of readmission, overpowering patient comorbidities. Importantly, postoperative complications identified before discharge from the hospital were not a strong predictor of readmission as the model using predischarge postoperative complications had a similar C index to our preoperative model (.68). However, the inclusion of complications identified after discharge from the hospital appreciably improved the predictive power of the model (C index, .78). The top five predictors of readmission in the final model based on patient comorbidities and postoperative complications were postdischarge deep space infection, superficial surgical site infection, pneumonia, myocardial infection, and sepsis. CONCLUSIONS: Readmissions in vascular surgery patients are mainly driven by postoperative complications identified after discharge. Thus, efforts to reduce vascular readmissions focusing on inpatient hospital data may prove ineffective. Our study suggests that interventions to reduce vascular readmissions should focus on prompt identification of modifiable postdischarge complications.

Outcomes of arterial resection during pancreatectomy for tumor.

OBJECTIVE: Arterial resection (AR) during pancreatic tumor resection is controversial. We examined the safety and efficacy of AR during pancreatectomy. METHODS: We used a prospective institutional database that includes 6522 patients who underwent pancreatectomy from 1970 to 2014; 35 had AR. We performed a 2:1 propensity match for patients without and with AR on the basis of preoperative patient and tumor variables. We then compared operative and postoperative outcomes between matched groups. RESULTS: AR included 18 hepatic, 8 celiac, 3 splenic, 3 middle colic, 2 superior mesenteric, and 1 left renal artery. There were 20 primary, 4 vein, and 2 graft reconstructions; 11 were emergent and 24 elective. Before matching, patients with AR were younger (58 ± 2 vs 63 ± 0.2 years old; P = .05), more likely to be of black race (26% vs 9%; P = .003), to have received preoperative chemotherapy (17% vs 2%; P < .001), have a later stage and larger tumor (4 ± 0.8 vs 3 ± 0.04 cm; P = .05), more resections that included removal of all macroscopic disease, but microscopic residual tumor remained (31% vs 14%; P = .02), greater blood loss (1285 ± 276 vs 822 ± 16 mL; P = .02), and more frequent cardiac complications (11% vs 4%; P = .03) compared with patients without AR. After propensity matching, baseline patient characteristics were similar between groups. For perioperative outcomes, the groups did not differ in surgical time, blood loss, length of stay, or complications including anastomotic leaks, bleeding, cardiac, infectious complications, or liver infarct or failure (all; P = not significant). Patency was 97% at a mean follow-up of 510 ± 184 days with 1 hepatic artery AR thrombosis. Long-term outcomes were significantly different: patients with AR had a lower rate of local tumor recurrence (20% vs 47%; P = .007) but also lower 1-year (50% vs 87%; P = .002) and median survival (22 ± 18 vs 49 ± 7 months; P = .002). CONCLUSIONS: AR during pancreatectomy is safe and not associated with increased complications. Although it significantly reduces the risk of local tumor recurrence, AR is associated with worse survival compared with patients who do not undergo AR.

Risk of venous thromboembolic events following inferior vena cava resection and reconstruction.

OBJECTIVE: The perioperative risk of an acute venous thromboembolism (VTE) event after inferior vena cava (IVC) reconstruction is unknown. We sought to describe VTE outcomes of our 15-year IVC reconstruction experience. METHODS: We performed a retrospective institutional review of all patients who underwent IVC reconstruction (September 1999-October 2014) and describe perioperative VTE outcomes. RESULTS: Sixty-five patients (mean age 58 ± 2 years) underwent IVC reconstruction (primary repair, 25%; patch, 43%; graft, 32%), most commonly for renal cell carcinoma (51%) and retroperitoneal sarcoma (22%). The overall incidence of perioperative VTE was 22% (n = 14), including isolated deep vein thrombosis (DVT) in 9% (n = 6) and pulmonary embolism in 12% (n = 8; 4 with concomitant DVT). Median time to diagnosis was 6 days (range, 1-37 days). Most VTE patients were symptomatic (57%; 8 of 14), including lower extremity edema in 50%, acute desaturation in 43%, and hemodynamic compromise in 36%. No patient died as a result of his or her VTE. There was a trend for more overall VTE events in patients who underwent graft reconstruction (primary, 13%; patch, 18%; graft, 33%; P = .06). VTE was also significantly associated with larger tumor size, renal vein reimplantation, and blood transfusions (P ≤ .05). Late complications of VTE included lower extremity edema in two patients and graft thrombosis in one patient. CONCLUSIONS: IVC reconstruction can be performed safely with low VTE-associated morbidity. Routine anticoagulation might not be warranted in these patients, but early postoperative screening for DVT should be considered, especially in cases with large tumor burden or when graft reconstruction is performed.

Contributions of planned readmissions and patient comorbidities to high readmission rates in vascular surgery patients.

OBJECTIVE: Administrative data show that among surgical patients, readmission rates are highest in vascular surgery. Herein we analyze the contribution of planned readmissions and patient comorbidities to high readmission rates in vascular surgery. METHODS: The 2012 to 2014 American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) data set was analyzed for overall and unplanned readmissions. Bivariable and multivariable risk adjustment analyses were performed using patient comorbidities to compare risks of overall and unplanned readmissions in vascular surgery compared with other specialties. RESULTS: Among 1,164,421 surgical patients, 86,403 underwent a vascular operation (other specialties included general surgery, 587,829 [51%]; orthopedic surgery, 211,507 [18%]; gynecology, 82,771 [7%]; urology, 62,153 [5%]; neurosurgery, 55,030 [4.7%]; plastic surgery, 32,318 [3%]; otolaryngology, 31,070 [2.6%]; and thoracic surgery, 15,340 [1%]). Incidence of 30-day readmission was 10.2% for vascular and 5.5% for other specialties (P < .0001). Planned readmissions were more frequent for vascular than for other specialties (8.8% vs 5.4%; P < .0001). In unadjusted analysis, vascular patients had significantly greater risk for overall readmission (odds ratio [OR], 1.97; 95% confidence interval [CI], 1.93-2.02; P < .0001) and unplanned readmission (OR, 1.89; 95% CI, 1.84-1.93; P < .0001) compared with other specialties. In bivariable analysis, vascular patients were older (67 ± 13 vs 56 ± 17 years) and had more comorbidities such as diabetes (31% vs 14%), dialysis dependence (6.3% vs 0.9%), American Society of Anesthesiology class III/IV status (84% vs 41%), and many others (all P < .0001). After risk adjustment for baseline differences between groups, vascular patients had a marginally greater overall risk of readmission compared with other specialties (OR, 1.04; 95% CI, 1.01-1.07; P < .0001), but the risk of unplanned readmission was not significantly different (OR, 0.98; 95% CI, 0.95-1.01; P = .13). CONCLUSIONS: Incidence of 30-day readmission after vascular surgery appears high, but after account for planned readmissions and risk adjustment, the risk of unplanned readmission is similar to that in other surgical patients. Thus, the use of readmission rate as a quality measure must account for more frequent planned vascular readmissions and patient-specific differences between vascular surgery and other specialties.

Outcomes of Bypass Support Use during Inferior Vena Cava Resection and Reconstruction.

BACKGROUND: The safety and effectiveness of using venovenous and cardiopulmonary bypass for resection of the inferior vena cava (IVC) is not well studied. The goal of this study was to compare outcomes following IVC resection with and without bypass support. METHODS: We analyzed all patients undergoing IVC resection at our institution (September 1999 to June 2014) and compared the use of bypass support with cross-clamp alone using univariable and Kaplan-Meier analyses. The outcomes included perioperative complications and survival. RESULTS: Sixty-three patients underwent IVC resection (mean age 58 ± 2 years, mean follow-up 21 ± 3 months). Bypass patients (32%) were similar to non-bypass patients (68%) in age, gender, tumor size, type, and grade (P = nonsignificant [NS]). Bypass patients were more likely to undergo complete IVC reconstruction (55% vs. 24%, P = 0.01) at the suprarenal level (62% vs. 35%, P = 0.05), and had higher intraoperative blood loss (9.6 ± 2.1 vs. 3.2 ± 1.4 L, P = 0.01). Complete R0 resection was similar between groups (50% vs. 52%, P = NS). There were more overall perioperative complications in bypass patients (P = 0.0005), with a trend toward more frequent venous thromboembolic events (40% vs. 21%, P = 0.13). The incidence of acute kidney injury (10% vs. 9%) and renal failure requiring dialysis (10% vs. 2%) was similar (P = NS). Length of stay was longer following bypass (12.2 ± 1.2 vs. 8.0 ± 0.1 days, P = 0.004). There were no differences in overall mortality (15% vs. 14%, P = NS) or tumor recurrence (50% vs. 47%, P = NS). Bypass patients had a nonsignificant trend toward longer disease-free survival (20.7 ± 5.2 vs. 10.4 ± 3.8 months, P = 0.12). CONCLUSIONS: The use of bypass support for IVC resection is associated with more complex operations and higher rates of perioperative complications. However, the overall mortality and morbidity of bypass, including renal complications, is similar to cross-clamping alone. Thus, the need for bypass should not preclude attempts at complete tumor resection.

Effect of patching on reducing restenosis in the carotid revascularization endarterectomy versus stenting trial.

BACKGROUND AND PURPOSE: The purpose is to determine whether patching during carotid endarterectomy (CEA) affects the perioperative and long-term risks of restenosis, stroke, death, and myocardial infarction as compared with primary closure. METHODS: We identified all patients who were randomized and underwent CEA in Carotid Revascularization Endarterectomy versus Stenting Trial. CEA patients who received a patch were compared with patients who underwent CEA with primary closure without a patch. We compared periprocedural and 4-year event rates, 2-year restenosis rates, and rates of reoperation between the 2 groups. We further analyzed results by surgeon specialty. RESULTS: There were 1151 patients who underwent CEA (753 [65%] with patch and 329 [29%] with primary closure). We excluded 44 patients who underwent eversion CEA and 25 patients missing CEA data (5%). Patch use differed by surgeon specialty: 89% of vascular surgeons, 6% of neurosurgeons, and 76% of thoracic surgeons patched. Comparing patients who received a patch versus those who did not, there was a significant reduction in the 2-year risk of restenosis, and this persisted after adjustment by surgeon specialty (hazard ratio, 0.35; 95% confidence interval, 0.16-0.74; P=0.006). There were no significant differences in the rates of periprocedural stroke and death (hazard ratio, 1.58; 95% confidence interval, 0.33-7.58; P=0.57), in immediate reoperation (hazard ratio, 0.6; 95% confidence interval, 0.16-2.27; P=0.45), or in the 4-year risk of ipsilateral stroke (hazard ratio, 1.23; 95% confidence interval, 0.42-3.63; P=0.71). CONCLUSIONS: Patch closure in CEA is associated with reduction in restenosis although it is not associated with improved clinical outcomes. Thus, more widespread use of patching should be considered to improve long-term durability. CLINICAL TRIAL REGISTRATION URL: http://www.clinicaltrials.gov. Unique identifier: NCT00004732.

Technical risk factors for portal vein reconstruction thrombosis in pancreatic resection.

OBJECTIVE: Vascular reconstruction can facilitate pancreas tumor resection, but optimal methods of reconstruction are not well studied. We report our results for portal vein reconstruction (PVR) for pancreatic resection and determinants of postoperative patency. METHODS: We identified 173 patients with PVR in a prospective database of 6522 patients who underwent pancreatic resection at our hospital from 1970 to 2014. There were 128 patients who had >1 year of follow-up with computed tomography imaging. Preoperative, intraoperative, and postoperative factors were recorded. Patients with and without postoperative PVR thrombosis were compared by univariable, multivariable, and receiver operating characteristic curve analyses. RESULTS: The survival of patients was 100% at 1 month, 88% at 6 months, 66% at 1 year, and 39% on overall median follow-up of 310 days (interquartile range, 417 days). Median survival was 15.5 months (interquartile range, 25 months); 86% of resections were for cancer. Four types of PVR techniques were used: 83% of PVRs were performed by primary repair, 8.7% with interposition vein graft, 4.7% with interposition prosthetic graft, and 4.7% with patch. PVR patency was 100% at 1 day, 98% at 1 month, 91% at 6 months, and 83% at 1 year. Patients with PVR thrombosis were not significantly different from patients with patent PVR in age, survival, preoperative comorbidities, tumor characteristics, perioperative blood loss or transfusion, or postoperative complications. They were more likely to have had preoperative chemotherapy (53% vs 9%; P < .0001), radiation therapy (35% vs 2%; P < .0001), and prolonged operative time (618 ± 57 vs 424 ± 20 minutes; P = .002) and to develop postoperative ascites (76% vs 22%; P < .001). Among patients who developed ascites, 38% of those with PVR thrombosis did so in the setting of tumor recurrence at the porta detected on imaging, whereas among patients with patent PVR, 50% did so (P = .73). Patients with PVR thrombosis were more likely to have had prosthetic graft placement compared with patients with patent PVRs (18% vs 2.7%; P = .03; odds ratio [OR], 7.7; 95% confidence interval [CI], 1.4-42). PVR patency overall was significantly worse for patients who had an interposition prosthetic graft reconstruction (log-rank, P = .04). On multivariable analysis, operative time (OR, 1.01; 95% CI, 1.01-1.02) and prosthetic graft placement (OR, 8.12; 95% CI, 1.1-74) were independent predictors of PVR thrombosis (C statistic = 0.88). CONCLUSIONS: Long operative times and use of prosthetic grafts for reconstruction are risk factors for postoperative portal vein thrombosis. Primary repair, patch, or vein interposition should be preferentially used for PVR in the setting of pancreatic resection.