Niten Singh

Preoperative risk score for the prediction of mortality after repair of ruptured abdominal aortic aneurysms

Objective: Even in the ruptured endovascular aneurysm repair first era, there are still patients who will not survive their ruptured abdominal aortic aneurysm (rAAA). All previously published mortality risk scores include intraoperative variables and are not helpful with the decision to operate or in providing preoperative patient and family counseling. The purpose of this study was to develop a practical preoperative risk score to predict mortality after repair of rAAA. Methods: Data of all patients with rAAA presenting between January 1, 2002, and October 31, 2013, were collected. Logistic regression was used to evaluate predictive variables both univariately and jointly, and the results of multivariate models guided the definition of the final simplified scoring algorithm. Results: There were 303 patients who presented during the study period. Sixteen patients died in the emergency department, en route to surgery, or after choosing comfort care. Preoperative variables most predictive of mortality were age >76 years (odds ratio [OR], 2.11; confidence interval [CI], 1.47‐4.97; P = .011), creatinine concentration >2.0 mg/dL (OR, 3.66; CI, 1.85‐7.24; P < .001), pH <7.2 (OR, 2.58; CI, 1.27‐5.24; P = .009), and systolic blood pressure ever <70 mm Hg (OR, 2.70; CI, 1.46‐4.97; P = .002). Assigning 1 point for each variable, patients were stratified according to the preoperative rAAA mortality risk score (range, 0‐4). For all repairs, at 30 days, patients with 1 point suffered 22% mortality; 2 points, 69% mortality; and 3 points, 80% mortality. All patients with 4 points died. There was a mortality benefit for ruptured endovascular aneurysm repair across all categories. Conclusions: Our rAAA mortality risk score is based on four variables readily assessed in the emergency department and allows accurate prediction of 30‐day mortality after repair of rAAAs. It also has a direct impact on clinical decision‐making by adding prognostic information to the decision to transfer patients to tertiary care centers and aiding in preoperative discussions with patients and their families. Graphical abstract: Figure. No caption available.

Three-vessel fenestrated and bilateral iliac branched graft repair of a juxtarenal aortic aneurysm with bilateral common iliac aneurysms

We describe a patient with large bilateral common iliac artery aneurysms as well as a large juxtarenal abdominal aortic aneurysm successfully treated by a novel approach. The procedure, completed in one setting, involved this sequence: positioning and deployment of bilateral iliac branch grafts with appropriate internal iliac limbs; insertion of a three-vessel fenestrated proximal device with cannulation and stenting of the left renal artery; and positioning and deployment of a bifurcated endograft and two mating limbs to the bilateral iliac branch device. The procedure was completed with percutaneous access; the patient recovered well and was discharged on postoperative day 1.

Aortic neck dilation is not associated with adverse outcomes after fenestrated endovascular aneurysm repair: Midterm results from an investigational device exemption clinical trial

Objective Long‐term outcomes after endovascular aneurysm repair (EVAR) are threatened by aortic neck dilation (AND), graft migration, and subsequent endoleak development. The aim of this study was to determine the rate of AND and the occurrence of endoleaks after fenestrated EVAR of juxtarenal aneurysms with physician‐modified endovascular grafts (PMEGs). Methods The study included 77 patients presenting with asymptomatic and ruptured juxtarenal abdominal aortic aneurysms treated with PMEGs who received radiologic follow‐up. Analysis of computed tomography images took place on a three‐dimensional workstation (TeraRecon, San Mateo, Calif). Aortic neck diameter was measured before and after EVAR at the lowest patent renal artery outer wall to outer wall. Significant AND was defined as >3‐mm increase between baseline and follow‐up, and sac regression >5 mm was considered significant. The patient’s 1‐month initial postoperative computed tomography measurement was considered baseline. The rate of AND was measured by comparing the baseline measurement with measurements at 6 months, 12 months, and annually thereafter up to 4 years. Results In this cohort of patients, 75% were men with a mean age of 74 ± 7.9 years. Median preoperative aneurysm size was 62 (57‐73) mm, and median follow‐up was 12 (3.5‐30) months. Mean endograft oversizing was 17% ± 12.5%, and mean seal zone length was 41 ± 11 mm. At 1‐year follow‐up, the median aortic neck increase was 1.7 (0‐3) mm. Maximum aneurysm size decreased dramatically during the first postoperative year, with significant sac regression in 65% of the patients. Aortic neck diameter at 1 year did correlate positively with the percentage of device oversizing. No other correlations were found. During the 4‐year follow‐up, there were no cases of type IA endoleaks. Conclusions AND does not influence outcome after endovascular repair of juxtarenal aneurysms using PMEGs. These midterm results support the applicability of PMEGs in juxtarenal aneurysm repair.

A Reliable Method for Renal Volume Measurement and Its Application in Fenestrated Endovascular Aneurysm Repair

Conclusions: In patients undergoing AVF surgery for hemodialysis access, delaying surgery for additional preoperative evaluation is associated with an increase in ED visits, an increase in CVC-related interventions, and an increase in general hospital visits compared with those without surgery delay. Only a small minority of the delayed surgery group underwent meaningful interventions to optimize surgery. These findings suggest that delaying surgery for further evaluation may be detrimental

Direct Anastomosis: Cephalic Vein Hemodialysis Access

The radiocephalic and brachiocephalic autogenous access approaches are first-line options for dialysis access and listed as “preferred” access by the National Kidney Foundation Dialysis Outcome Quality Initiative (K/DOQI) most recent 2006 guidelines. Both have superior long-term patency to prosthetic grafts in meta-analyses. This chapter focuses on direct anastomosis cephalic vein hemodialysis access, techniques, patency, and outcomes.

In Patients with Popliteal Entrapment Syndrome, Does Surgery Improve Quality of Life?

Popliteal entrapment syndrome (PES) is a rare disorder characterized by popliteal artery compression and symptoms of lower extremity ischemia. It is divided into two main subgroups – anatomic and functional popliteal entrapment. Anatomic popliteal entrapment was first described in the 1870s and is caused by abnormal anatomic development of the popliteal artery and/or gastrocnemius muscle. Functional PES is caused by hypertrophy of the gastrocnemius/soleus complex in anatomically normal subjects. Patients typically present in the second to third decades of life, are physically active and may be professional athletes, and have no other cardiovascular risk factors for the development of vascular disease. Surgical intervention via myotomy of the medial head of the gastrocnemius or myotomy plus interposition vein or prosthetic graft for more advanced disease remains the cornerstone of therapy for these patients; however long-term quality of life data is limited to retrospective reviews.

Hemodialysis in the Morbidly Obese

Obesity has increased substantially in the American population over the past two decades. Given this significant increase and the association with hypertension and diabetes, the hemodialysis access surgeon must be comfortable in creating functioning access in obese patients. Obese patients are at increased risk for surgical site infections, have deeper anatomic structures that may limit dialysis cannulation, and are in a systemic proinflammatory and prothrombotic state. The successful creation of hemodialysis access often requires adjunctive procedures to increase the produced reliable access, and techniques that have demonstrated efficacy include transposition, elevation, lipectomy, minimal incision superficialization technique (MIST), and suction lipectomy (liposuction). When autogenous fistula creation is not possible necessitating a graft for permanent access, adjunctive intraoperative procedures are useful, particularly with tunneling, in allowing repeated successful dialysis. Obese patients are also impacted by the need for tunneled dialysis catheters and may develop a central vein stenosis or occlusion. In this patient group, upper extremity dialysis access is preferred over the lower extremity, and Hemodialysis Reliable Outflow (HeRO) may provide a useful manner for successful dialysis.

FT17. Factors Predicting Limb Salvage in Acute Limb Ischemia Treated at a Tertiary Referral Center

Objectives: In treating critical limb ischemia (CLI), bypass grafting to tibial or paramalleolar arteries plays pivotal role. Though the graft flow (GF) differs significantly among patients, the factors associated with GF are not well studied. Herein, we assessed the factors and developed the predictive equation of GF in tibial or paramalleolar bypass grafting. Methods: CLI patients treated in our institution from January 2012 to November 2016, with bypass to tibial or paramalleolar arteries, were enrolled. In the 137 bypass grafts, 43 grafts were excluded in which postoperative ultrasound imaging within 1 month detected flow-limiting abnormalities. A total of 94 normal grafts were finally enrolled and randomly allotted to two groups: development data set for GF equation (74 grafts) and equation validation data set (20 grafts). Multivariate analysis with stepwise selection was performed to assess and detect factors associated with GF and to obtain GF predictive equation. Analyzed variables were sex, age, runoff, hemodialysis (HD), diabetes mellitus (DM), graft quality (GQ), hypertension, dyslipidemia, smoking history, inflow site, body mass index, cerebrovascular disease, ischemic cardiac disease, and foot infection. Runoff was evaluated with intraoperative angiography, and graded according to Rutherford runoff scoring system; then, the runoff score was classified into three groups: good, fair, or poor. The estimated equation was validated by Bland-Altman method and Student t-test. Actual GF was measured intraoperatively with transit time flowmeter.

Liposuction Superficialization of Brachiocephalic Fistulae

Reliable, mature arteriovenous access is critical in optimizing outcomes for patients with end-stage renal disease. Within this patient population, there is a subset of patients who undergo brachiocephalic fistula creation given the surgical accessibility of the brachial artery and cephalic vein near the antecubital fossa. Liposuction superficialization of a brachiocephalic arteriovenous fistula is a technique that is employed when the fistula matures and is anatomically deep within the upper arm, making reliable hemodialysis access cannulation difficult. The technique begins with ultrasound-guided infiltration of tumescent solution (normal saline, lidocaine, and epinephrine) into the subcutaneous adipose and soft tissue. Once the tissue has firm turgor, a small incision is made distal to the fistula, and suction lipectomy is performed under direct and constant ultrasound guidance. As the procedure is performed under ultrasound guidance, complications (hematoma, active bleeding, or pseudoaneurysm) are rarely encountered. The arm is dressed with a sterile dressing and elastic bandage for 72 h with a repeat ultrasound and wound check at 1 week. A final ultrasound is performed at 1 month, and if the vein is adequately superficialized and mature, hemodialysis access may be attempted. Outcomes from this procedure seem acceptable with an 85 % success in two-needle cannulation at 1 month.