Samuel L. Chen

Outcomes of open and endovascular lower extremity revascularization in active smokers with advanced peripheral arterial disease

Objective: Concern over perioperative and long‐term durability of lower extremity revascularizations among active smokers is a frequent deterrent for vascular surgeons to perform elective lower extremity revascularization. In this study, we examined perioperative outcomes of lower extremity endovascular (LEE) revascularization and open lower extremity bypass (LEB) in active smokers with intermittent claudication (IC) and critical limb ischemia (CLI). Methods: Active smokers undergoing LEE or LEB from 2011 to 2014 were identified in the American College of Surgeons (ACS) National Surgical Quality Improvement Program (NSQIP) targeted vascular data set. Patient demographics, comorbidities, anatomic features, and perioperative outcomes were compared between LEE and LEB procedures. Subgroup analysis was performed for patients undergoing revascularization for IC and CLI independently. Results: From 2011 to 2014, 4706 lower extremity revascularizations were performed in active smokers (37% of all revascularizations). In this group, 1497 were LEE (55.6% for CLI, 13.4% for below‐knee pathology) and 3209 were LEB (68.9% CLI, 34.7% below‐knee). Patients undergoing LEE had higher rates of female gender, hypertension, end‐stage renal disease, and diabetes (all P ≤ .02). LEE patients also had a higher frequency of prior percutaneous interventions (22.7% vs 17.2%; P < .01) and preoperative antiplatelet therapy (82.3% vs 78.7%; P = .02). On risk‐adjusted multivariate analysis, LEE patients had higher need for reintervention on the treated arterial segment than LEB (5.1% vs 5.2%; odds ratio [OR], 1.52; 95% confidence interval [CI], 1.08‐2.13; P = .02) but had lower wound complications (3.1% vs 13.2%; OR, 0.32; 95% CI, 0.23‐0.45; P < .01) and no statistically significant difference in 30‐day mortality (0.6% vs 0.9%), myocardial infarction or stroke (1.1% vs 2.6%), or major amputation (3.2% vs 2.1%) in the overall cohort of active smokers. In the IC subgroup, myocardial infarction or stroke was significantly higher in the LEB group (1.9% vs 0.6%; OR, 1.83; 95% CI, 1.17‐1.97; P = .03), although no difference was found in the CLI subgroup (2.8% vs 1.4%; OR, 0.75; 95% CI, 0.37‐1.52; P = .42,). Also in IC group, there was a trend for lower major amputation rates ≤30 days in the LEE group, whereas in the CLI group, LEE had a trend toward higher risk of early amputation compared with LEB. Conclusions: In active smokers, LEB for IC and CLI requires fewer reinterventions but is associated with a higher rate of postoperative wound complications compared with LEE revascularization. However, the risk for limb amputation is higher in actively smoking patients when treated by LEE compared with LEB for CLI. Importantly, cardiovascular complications are significantly higher in actively smoking patients with IC undergoing LEB compared with LEE. This additional cardiovascular risk should be carefully weighed when proposing LEB for actively smoking patients with nonlimb‐threatening IC.

Comparison of percutaneous versus open femoral cutdown access for endovascular repair of ruptured abdominal aortic aneurysms

Objective Ruptured endovascular aortic aneurysm repair (REVAR) is being increasingly used to treat ruptured abdominal aortic aneurysms (rAAAs). However, the comparison between totally percutaneous (pREVAR) vs femoral cutdown (cREVAR) access for REVAR has not been studied. We used a national surgical database to evaluate the 30‐day outcomes in patients undergoing pREVAR vs cREVAR. Methods Patients who underwent EVAR for rAAA between 2011 and 2014, inclusively, were studied in the American College of Surgeons (ACS) National Surgical Quality Improvement Program (NSQIP) targeted vascular database. Univariate and multivariate analyses were used to compare preoperative demographics, operation‐specific variables, and postoperative outcomes between those who had pREVAR and cREVAR. Results We identified 502 patients who underwent REVAR, of which 129 had pREVAR (25.7%) and 373 cREVAR (74.3%). Between 2011 and 2014, the use of totally percutaneous access for repair increased from 14% to 32%. Of all patients undergoing REVAR, 24% had bilateral percutaneous access, 2% had attempted percutaneous access converted to cutdown, 64% had bilateral femoral cutdowns, and 10% had single femoral cutdown. Univariate analysis showed there were no significant differences in age, gender, body mass index, AAA size, or other high‐risk physiologic comorbidities between the two groups. There was also no difference in rates of preoperative hemodynamic instability (48.1% vs 45.0%; P = .55) or need for perioperative transfusion (67.4% vs 67.8%; P = .94). There was a higher incidence of use of regional anesthesia for pREVAR compared with cREVAR (20.9% vs 7.8%; P < .01). The incidence of postoperative wound complications was similar between both groups (4.8% vs 5.4%; P = .79), whereas hospital length of stay was shorter in the pREVAR group (mean difference, 1.3 days). Overall 30‐day mortality was higher in the pREVAR group (28.7% vs 20.1%; P = .04), and operative time was longer (mean difference, 6.3 minutes). However, when pREVARs done in 2011 to 2012 were compared with those done in 2013 to 2014, 30‐day mortality decreased from 38.2% to 25.3% and operative time decreased by 25 minutes (188 to 163 minutes). Multivariate analysis showed there were no significant differences in mortality, wound complications, hospital length of stay, or operative time between pREVAR and cREVAR. Conclusions The ACS NSQIP targeted vascular database shows that there has been increased adoption of pREVAR in recent years, with improved mortality and operative time over the 4‐year study period. At this point, pREVAR has not yet been shown to be superior to cREVAR for rAAA, but these outcome improvements are encouraging and likely attributable to increased operator experience.

Perioperative risk factors for hospital readmission after elective endovascular aortic aneurysm repair

Background Elective endovascular aneurysm repair (EVAR) is generally well tolerated. However, the incidence of hospital readmission after EVAR and the risk factors and reasons for it are not well studied. This study sought to determine the incidence, to characterize the indications, and to identify perioperative patient‐centered risk factors for hospital readmission within 30 days after elective EVAR. Methods All patients who underwent EVAR electively in 2012 to 2013 were identified from the American College of Surgeons National Surgical Quality Improvement Program Targeted Vascular database (n = 3886). Preoperative demographics, operation‐specific variables, and postoperative outcomes were compared between those who were readmitted within 30 days of the index operation and those who were not. Multivariate logistic regression was then used to determine independent predictors of hospital readmission. Results The unadjusted 30‐day readmission rate after EVAR was 8.2%. Of all readmissions, 55% were for reasons related to the procedure. Median time to readmission was 12 days. Significant preoperative risk factors associated with readmission were female sex, preoperative steroid use, congestive heart failure, and dialysis dependence (P < .05). Multiple postoperative medical complications were independently predictive of readmission, including myocardial infarction and deep venous thrombosis (P < .05). Surgical complications that were independently predictive of readmission were surgical site infection (odds ratio, 10.24; 95% confidence interval, 5.31‐19.75; P < .01) and need for unplanned reoperation (odds ratio, 17.50; 95% confidence interval, 10.43‐29.37; P < .01). Readmitted patients ultimately had significantly higher rates of 30‐day mortality (3.5% vs 0.3%; P < .01). Conclusions Hospital readmissions remain a costly problem after vascular surgery and are associated with 30‐day mortality after elective EVAR. Whereas female sex and certain irreversible medical comorbidities are nonmodifiable, focusing on medical optimization and identifying those perioperative variables that can affect the need for post‐EVAR interventions will be an important step in decreasing hospital readmission.

Physiologic Cryoamputation in Managing Critically Ill Patients with Septic, Advanced Acute Limb Ischemia

BACKGROUND Certain critically ill patients with advanced acute limb ischemia with a nonviable extremity may be unsuitable for transport to the operating room to undergo definitive amputation. In these unstable patients, rapid regional cryotherapy allows for prompt infectious source control and correction of hemodynamic and metabolic abnormalities, thereby lessening the risk associated with definitive surgical amputation. We describe our refined technique for lower extremity physiologic cryoamputation and review our institutional experience. METHODS After adequate analgesia is administered to the patient, a heating pad is secured circumferentially at the proximal amputation margin and the affected extremity is placed in a customized Styrofoam cooler. A circumferential seal is secured at the proximal chill zone without use of a tourniquet and dry ice is placed into the cooler to surround the entire affected leg. Delayed definitive lower extremity amputation is later performed when hemodynamic and metabolic derangements are corrected. RESULTS We reviewed 5 patients who underwent lower extremity cryoamputation with this technique identified at our institution between 2005 and 2015. Age ranged from 31 to 79 years old. All presented with severe foot infection and septic shock requiring vasopressor support. All 5 patients stabilized hemodynamically following the initial cryoamputation and later underwent definitive lower extremity amputation, with a median time of 3 days following initial cryoamputation. CONCLUSIONS Lower extremity physiologic cryoamputation is an effective, immediate bedside procedure that can provide local source control and the opportunity for correction of metabolic derangements in initially unstable patients to lessen the risk for definitive major lower extremity amputation. Refinement of the cryoamputation technique, as described in this report, allows for a predictable and reproducible physiologic amputation.

Outcomes of Open and Endovascular Lower Extremity Revascularization in Current Smokers With Intermittent Claudication and Critical Limb Ischemia

Objective: Active smoking is a frequent deterrent to performance of elective lower extremity revascularization. In this study, we aimed to examine perioperative outcomes of endovascular lower extremity revascularization (LEE) and open lower extremity bypass (LEB) in active smokers with claudication or critical limb ischemia (CLI). Methods: Active smokers undergoing LEE or LEB from 2011 to 2014 were identified in the American College of Surgeons National Surgical Quality Improvement Program targeted vascular data set. Patient demographics, comorbidities, anatomic features, and perioperative outcomes were compared between LEE and LEB procedures. Subgroup analyses were then performed for patients undergoing revascularization for claudication vs CLI. Results: A total of 4706 cases were identified, of which 1497 were LEE (55.6% for CLI, 13.4% for below-knee disease) and 3209 were LEB (68.9% CLI, 34.7% below-knee disease). Patients undergoing LEE had higher rates of hypertension, end-stage renal disease, and diabetes. LEE patients also had higher rates of prior percutaneous interventions (22.7% vs 17.2%) and preoperative antiplatelet therapy (82.3% vs 78.7%). On risk-adjusted multivariate analysis (Table), LEE had a higher need for reintervention than LEB (adjusted odds ratio [AOR], 1.52; 95% confidence interval [CI], 1.08-2.13; P 1⁄4 .02) but fewer wound complications (AOR, 0.32; 95% CI, 0.23-0.45; P < .01). Therewereno statistically significantdifferences in30-daymortality,myocardial infarction, or stroke or major amputation between the two groups. In the claudication subgroup, the rate of myocardial infarction or stroke was significantly lower in the LEE group compared with open bypass (AOR, 0.17; 95% CI, 0.03-0.83; P 1⁄4 .03), although this difference was not found in the CLI subgroup. In addition, whereas there was a trend toward less progression to major amputation among claudicants undergoing LEE, in patients with CLI, LEE appeared to confer a higher risk of amputation compared with open bypass. A summarized overview of the results can be found in the Table. Conclusions: In active smokers, open bypass carries with it higher rates of wound complications compared with endovascular procedures, although they require fewer reinterventions and have similar cardiovascular risk profiles. However, in claudicants undergoing endovascular revascularization, cardiovascular risk is significantly lower than with open bypass, and it should be considered in offering intervention.

Endovascular Management of Concomitant Thoracic and Abdominal Aortic Ruptures Resulting from Brucellosis Aortitis

BACKGROUND Acute aortic symptomatology is an unusual manifestation of Brucella melitensis infection. We present a rare case of acute multifocal thoracic and abdominal aortic ruptures arising from Brucellosis aortitis managed exclusively with endovascular surgery. METHODS A 71-year-old Hispanic male with a history of atrial fibrillation and prior stroke on chronic anticoagulation presented with shortness of breath and malaise. In addition, he had been treated approximately 1 year previously in Mexico for B. melitensis bacteremia after eating fresh unpasteurized cheese. Computed tomography (CT) angiography demonstrated an acute rupture of the descending thoracic aorta just proximal to the celiac trunk and synchronous rupture at the abdominal aortic bifurctation. RESULTS The patient was taken emergently to the hybrid operating room, where synchronous supraceliac thoracic aorta and abdominal aortoiliac stent grafts were deployed under local anesthesia. Completion angiography demonstrated total exclusion of the thoracic and abdominal extravasation with no evidence of endoleak. Twenty hours postoperatively, the patient became acutely obtunded and hypotensive. Repeat CT angiography demonstrated contrast extravasation at the level of the excluded aortic bifurcation. Emergent angiography confirmed a type II endoleak with free extraluminal rupture. Multiple coils were placed at the level of the aortic bifurcation between the left limb of the stent graft and the aortic wall to tamponade the endoleak. No further extravasation was noted on final aortography. Postoperatively, blood cultures confirmed the diagnosis of B. melitensis. The patient was treated with systemic doxycycline, gentamicin, and rifampin. Resolution of the acute event occurred without additional sequelae and he was discharged from the hospital to a rehabilitation facility. CONCLUSIONS Concomitant multifocal aortic ruptures arising from Brucellosis aortic infection is a very rare event. In this case, the patient was successfully treated with thoracic and abdominal endovascular stent-graft exclusion, coiling, and long-term targeted antibiotics.

Geometric changes of the inferior vena cava in trauma patients subjected to volume resuscitation

Objective Dynamic changes in anatomic geometry of the inferior vena cava from changes in intravascular volume may cause passive stresses on inferior vena cava filters. In this study, we aim to quantify variability in inferior vena cava dimensions and anatomic orientation to determine how intravascular volume changes may impact complications of inferior vena cava filter placement, such as migration, tilting, perforation, and thrombosis. Methods Retrospective computed tomography measurements of major axis, minor axis, and horizontal diameters of the inferior vena cava at 1 and 5 cm below the lowest renal vein in 58 adult trauma patients in pre-resuscitative (hypovolemic) and post-resuscitative (euvolemic) states were assessed in a blinded fashion by two independent readers. Inferior vena cava perimeter, area, and volume were calculated and correlated with caval orientation. Results Mean volumes of the inferior vena cava segment on pre- and post-resuscitation scans were 9.0 cm3 and 11.0 cm3, respectively, with mean percentage increase of 48.6% (P < 0.001). At 1 cm and 5 cm below the lowest renal vein, the inferior vena cava expanded anisotropically, with the minor axis expanding by an average of 48.7% (P < 0.001) and 30.0% (P = 0.01), respectively, while the major axis changed by only 4.2% (P = 0.11) and 6.6% (P = 0.017), respectively. Cross-sectional area and perimeter at 1 cm below the lowest renal vein expanded by 61.6% (P < 0.001) and 10.7% (P < 0.01), respectively. At 5 cm below the lowest renal vein, the expansion of cross-sectional area and perimeter were 43.9% (P < 0.01) and 10.7% (P = 0.002), respectively. The major axis of the inferior vena cava was oriented in a left-anterior oblique position in all patients, averaging 20° from the horizontal plane. There was significant underestimation of inferior vena cava maximal diameter by horizontal measurement. In pre-resuscitation scans, at 1 cm and 5 cm below the lowest renal vein, the discrepancy between the horizontal and major axis diameter was 2.1 ± 1.2 mm (P < 0.001) and 1.7 ± 1.0 mm (P < 0.001), respectively, while post-resuscitation studies showed the same underestimation at 1 cm and 5 cm below the lowest renal vein to be 2.2 ± 1.2 mm (P < 0.01) and 1.9 ± 1.0 mm (P < 0.01), respectively. Conclusions There is significant anisotropic variability of infrarenal inferior vena cava geometry with significantly greater expansive and compressive forces in the minor axis. There can be significant volumetric changes in the inferior vena cava with associated perimeter changes but the major axis left-anterior oblique caval configuration is always maintained. These significant dynamic forces may impact inferior vena cava filter stability after implantation. The consistent major axis left-anterior oblique obliquity may lead to underestimation of the inferior vena cava diameter used in standard anteroposterior venography, which may influence initial filter selection.