Jason Chiriano

Effects of Prior Abdominal Surgery, Obesity, and Lumbar Spine Level on Anterior Retroperitoneal Exposure of the Lumbar Spine

OBJECTIVE To evaluate the effects of prior abdominal surgery and obesity and the level of spine exposure on the technical aspects and complications of anterior retroperitoneal exposure of the lumbar spine (ARES). DESIGN Retrospective review of prospective database. SETTING Academic vascular surgery practice. PATIENTS Patients undergoing ARES from 2001 to 2011. MAIN OUTCOME MEASURES Influence of prior abdominal surgery, obesity, and level of exposure on time to spine exposure and incidence of vascular and perioperative complications. RESULTS Four hundred seventy-six patients underwent ARES. Mean (SD) age was 47.7 (12.6) years; 46.6% had undergone prior abdominal surgery. Mean (SD) body mass index (BMI) was 28.3 (5.5); 61.6% of procedures included the L4-5 disk. Mean (SD) time to exposure was 70.0 (25.5) minutes. Vascular injury occurred in 23.3% (3.8% major). Perioperative complications occurred in 16.4% of cases. Prior abdominal surgery had no effect on time to exposure, vascular injury, and perioperative complications. A BMI of 30 or more had no effect on time to exposure compared with a lower BMI. A BMI of 30 or more led to higher rates of vascular injury (30.8% vs 19.7%; P = .007) and overall complications (21.4% vs 14.0%; P = .04). Exposures involving L4-5 led to increased time to exposure (77.0 vs 56.2 minutes; P < .001) and higher rates of vascular injury (29.7% vs 13.1%; P < .001) but had no effect on overall complications compared with exposures for other levels. CONCLUSION Prior abdominal surgery should not be considered a contraindication to ARES. Caution is warranted in obese patients and exposures involving L4-5.

Carotid duplex ultrasound changes associated with left ventricular assist devices.

BACKGROUND Carotid duplex ultrasound (CDUS) is often used as a screening test in cardiac patients. Significant cardiac dysfunction may affect the accuracy of CDUS because of alterations in the cardiac cycle. Left ventricular assist devices (LVADs) are frequently implanted as a bridge to cardiac transplant. A review of CDUS in patients with LVADs was performed to assess their influence on arterial waveforms and velocities. METHODS Patients with LVADs undergoing carotid duplex in our Intersocietal Commission for the Accreditation of Vascular Laboratories (ICAVL)-accredited vascular laboratory were identified. The carotid waveforms were analyzed qualitatively and quantitatively. Common carotid artery (CCA) and internal carotid artery (ICA) peak-systolic and end-diastolic velocities (PSV and EDV) were recorded as ICA/CCA velocity ratios. In patients with prior CDUS, the changes between these values were analyzed before and after LVAD placement. RESULTS Of the 14 patients with LVADs treated in our institution over the past 2 years, 4 had CDUS (8 ICAs). Mean age was 57 years, and 3 of the 4 patients were men. All patients were free of cerebrovascular symptoms. Qualitatively, there was significant blunting of the CCA and ICA waveforms noted in all 8 ICAs. The degree of stenosis was reported as ≤15% in 7 ICAs and 15-45% in 1 ICA. The mean ICA PSV was 61.8 cm/sec. Two patients (4 ICAs) had CDUS before and after LVAD placement. Comparing pre- and post-LVAD values, the mean ICA PSV decreased by 42% (54 cm/sec; P = 0.04) and EDV increased by 51% (17 cm/sec; P = 0.3). The PSV and EDV ratios were unchanged. Overall assessment of category of stenosis was unchanged in 2 ICAs (≤15%), one decreased from moderate to mild (45-70% to 15-45%), and one ICA changed from 45-70% to ≤15% based on the decreased ICA PSV. CONCLUSIONS The presence of an LVAD has a significant influence on CDUS findings. There is a qualitative change in the ICA with blunting of the waveform, and a quantitative change with a decreased PSV and an increased EDV. Compared with pre-LVAD placement, there is a significant decrease in PSV which may affect the accuracy of CDUS using velocity-based criteria. Further study into the accuracy of CDUS in patients with LVADs is necessary.

Comparison of Nonpenetrating Titanium Clips versus Continuous Polypropylene Suture in Dialysis Access Creation.

BACKGROUND Nonpenetrating titanium surgical clips (clips) offer a theoretical advantage of inducing less intimal hyperplasia at an anastomosis because of less endothelial injury. Whether this translates into improved outcomes when used in the creation of arteriovenous fistulas (AVFs) remains unclear. We sought to compare the maturation, patency, and failure rates of anastomoses created using traditional continuous polypropylene suture and clips. METHODS All primary AVF created at a single Veterans Administration Medical Center were reviewed over a 6-year period. Anastomoses were created with either clips or suture based on surgeon preference. Patient characteristics and surgical outcomes were collected. Comparisons were made between the 2 groups. RESULTS Over a 6-year period, 334 fistulas were created (29% suture and 71% clips) in 326 patients. The mean age was 64.8 ± 11 years with 98% males. Comorbidities included diabetes (70%), hypertension (96.1%), and tobacco use (52.9% previous or current). Approximately half the patients were predialysis. Comparison of patient characteristics showed no differences between the suture and clip groups. There was no significant difference in maturation rate (suture 79% versus clips 72%, P = 0.25), median time to maturation (suture 62 ± 35 versus clips 71 ± 13 days, P = 0.07), 1 year primary patency rate (suture 37.4% versus clips 39.6, P = 0.72), 1 year assisted primary patency rate (suture 82.4% versus clips 76.3%, P = 0.31), or overall failure rates (suture 62% versus clips 58%, P = 0.56). Median time to initial failure or reintervention was not significantly different in the clip group (suture 615 [range, 239-991] versus clips 812 [range, 635-989] days, P = 0.72). CONCLUSIONS Compared to traditional polypropylene suture creation of upper extremity AVFs, nonpenetrating clips had equivalent maturation, 1-year patency, and overall failure rates. Neither clips nor suture offers any clear advantage in the creation of AVF.

Preoperative carotid duplex findings predict carotid stump pressures during endarterectomy in symptomatic but not asymptomatic patients.

BACKGROUND Carotid stump pressure (CSP) is frequently measured to determine the need for shunt use during carotid endarterectomy (CEA). We hypothesized that the preoperative carotid duplex examination correlates with preoperative symptoms and intraoperative CSP. METHODS Patients undergoing CEA over a 7-year period were identified from our vascular registry. CEA was performed with selective shunting on the basis of intraoperative CSP <30 mm Hg regardless of symptoms or contralateral internal carotid artery (ICA) stenosis. The preoperative duplex was categorized by ipsilateral and contralateral ICA diameter-reduction stenosis (<15%, 15-45%, 45-70%, 70-99% [severe] and occluded), and the direction of vertebral artery flow. The relationships among preoperative duplex findings, symptom status, and CSP were evaluated using unpaired t-test and Chi-square analysis. RESULTS A total of 303 CEAs were performed. Stump pressures were documented in 284 patients, which comprised the study population. Asymptomatic severe stenosis was the indication for CEA in 179 cases (59.1%). Symptomatic patients (Sx) had significantly lower stump pressures than asymptomatic (ASx) patients (40.72 ± 16.27 vs. 45.8 ± 17.64 mm Hg, p = 0.0167). Fifty-seven patients (19%) had contralateral severe ICA stenosis or occlusion. Contralateral ICA stenosis or occlusion had significantly lower CSP than those with lesser degrees of stenosis (39.24 ± 15 vs. 44.82 ± 17.62 mm Hg, p = 0.0267). Contralateral ICA severe stenosis or occlusion correlated with lower CSP in Sx patients (32.05 ± 8.24 vs. 42.92 ± 16.95 mm Hg, p = 0.038) but not in ASx patients (43.2 ± 16 vs. 46.29 ± 17.5 mm Hg, p = 0.39). CSP was <30 mm Hg in 63% of Sx patients and 24% of ASx patients (p = 0.012). Overall shunt usage was 84/2,842 (9.5%). Perioperative stroke and death rate was 2.7%. Perioperative stroke did not correlate with the presence of contralateral occlusion, or severity of contralateral stenosis. CONCLUSIONS Symptomatic patients undergoing CEA have lower stump pressures than ASx patients overall and also in the presence of contralateral disease. The incidence of perioperative stroke was not predicted by severity of contralateral disease. A strategy of selective shunting seems appropriate even in Sx patients with contralateral severe stenosis or occlusion. Although a high-risk cohort for perioperative neurologic events exists and may include those with symptomatic disease and contralateral severe stenosis or occlusion, further study is warranted to define the patients who will clinically benefit from shunt placement.

Distal Radial Artery Embolization: An Alternative Approach towards Access Preservation and Limb Salvage in Radiocephalic Arteriovenous Fistulae Complicated by Steal Syndrome

The incidence of radiocephalic arteriovenous fistulae complicated by ischemic steal syndrome is low; however, its sequelae can be quite devastating. Traditional management includes open ligation of the distal radial artery. This series details 4 cases of successful embolization of the distal radial artery for flow interruption to treat ischemic steal syndrome and salvage functional dialysis access. For radiocephalic arteriovenous fistulae complicated by steal syndrome, distal radial artery endovascular coil embolization is a valuable treatment strategy.

Rupture Of An Abdominal Aortic Aneurysm Following Nonaccidental Blunt Abdominal Trauma

A 78-year-old woman presented to our trauma center with an initial, erroneous history of a ground-level fall. Further investigation revealed that the patient had been assaulted by her husband immediately prior to presentation. The initial abdominal examination was benign, and the patient was hemodynamically stable. The patient was found to have a large subdural hematoma (SDH). Following open evacuation of the SDH, the patient developed ongoing hemodynamic instability. Further evaluation with computed tomography of the abdomen and pelvis uncovered the diagnosis of a 6 cm abdominal aortic aneurysm (AAA) with a large retroperitoneal hematoma. The patient underwent emergent repair of the ruptured AAA. There were no other significant intra-abdominal injuries, and the patient had an uneventful recovery. This case highlights the need for thorough evaluation of the trauma patient and recognition of the possibility of coexistent AAA in the elderly trauma patient. We believe that this is the first reported case of a ruptured AAA following nonaccidental blunt abdominal trauma.

Lower Extremity Amputations

Lower extremity amputations represent the end stage of atherosclerotic disease as well as diabetic pathology. The vascular surgeon must be familiar with all aspects of lower extremity amputations including indications, the technical aspects of the procedure, as well as the expected outcomes. This chapter will focus on patient selection, various amputation techniques, complications, as well as prognostic factors for successful outcomes of the amputation procedure.

Lower-Extremity Thromboembolectomy

Lower-extremity thromboembolectomy is performed for patients with acute limb ischemia secondary to a thromboembolic disease to the lower extremity. This chapter describes indications, essential steps, variations, and complications of this procedure. It provides a detailed template operative note for the procedure.