Spinal Cord Ischemia Rescue after Hybrid Total Arch Repair with Frozen Elephant Trunk: A Case Report.

Frozen elephant trunk repair is a technique described to simplify total arch repair for Stanford type A aortic dissection. Spinal cord ischemia is a devastating complication after frozen elephant trunk repair. In this report, we describe a case of spinal cord ischemia resulting in paralysis after frozen elephant trunk repair. Our spinal cord ischemia protocol was implemented and rescued patients from paraplegia. We report a dedicated spinal cord ischemia protocol that can rescue patients from paraplegia after hybrid arch repair with frozen elephant trunk.

A novel perfused porcine simulator for teaching aortic anastomosis increases resident interest in vascular surgery.

OBJECTIVE: This report describes a novel simulator, euthanized pigs on cardiopulmonary bypass, and validates this simulator with a controlled trial in general surgery residents learning aortic anastomosis. We evaluated this novel simulator with the following hypothesis: our porcine perfused simulator is as good as or better than the standard rubber tubing, low-fidelity models used for vascular anastomotic training. METHODS: Euthanized pigs were placed on cardiopulmonary bypass, creating a perfused, ex vivo model on which to perform surgical procedures. The participants in the study were postgraduate year 2, 3, and 4 general surgery residents. Residents were randomized to practice aortic anastomosis in the pig laboratory (PL) simulator or in a dry laboratory. The PL residents and control residents performed a first vascular anastomosis on the rubber tube model. Anastomosis creation was filmed. The anastomosis and video were stored for later grading. Next, all residents underwent an ungraded, one-on-one training session with the attending vascular surgeon. After the training session, all residents completed a second videotaped rubber tubing anastomosis. The grading scales used were validated by other authors: Global Assessment Score, Final Product Score, and Checklist Scoring Instrument. Survey data describing this experience were collected using a 13-question prelaboratory and 16-question postlaboratory questionnaires consisting of yes/no, multiple selection, and 5-point Likert-type scale questions. RESULTS: All residents had a statistically significant improvement in time to completion and in the Global Assessment Score with tutored practice. The PL residents showed statistically significant improvement in completion time between the first and second videotaped anastomosis; however, there was no statistically significant improvement in the scoring metrics. The control residents showed statistically significant improvement in all three scoring metrics, but no statistically significant difference was found in completion time. The survey data showed a statistically significant shift in considering vascular surgery as a career after the experience in the PL group (P = .05) compared with the control group, who had no change in interest (P = .91). CONCLUSIONS: Our prospective, randomized clinical trial shows that the porcine cardiopulmonary bypass model achieves similar results to a previously validated bench top model while improving general surgery resident interest in vascular surgery as a career.

Outcomes in Critical Limb Ischemia Compared by Distance from Referral Center.

BACKGROUND: Little data exist regarding the effect of referral distance on outcomes after revascularization for critical limb ischemia (CLI). We tested the assumption that patients who travel longer distances for revascularization procedures have worse outcomes. METHODS: We identified a retrospective cohort of 300 CLI patients who underwent revascularization between January 1, 2000 and December 31, 2010 at a single academic medical center. Patients were stratified into 2 groups based on distance greater than or less than 100 miles from the referral center. The association between travel distance and outcome measures including length of stay (LOS), postoperative functional status, hospital disposition, patient follow-up, and amputation-free survival (AFS) were evaluated using Cox proportional hazard models controlling for patient comorbidities and type of revascularization procedure. RESULTS: One hundred eighteen (39%) patients travelled >100 miles for CLI revascularization. The 2 groups had similar baseline characteristics. Overall, 211 (70%) patients underwent an open revascularization, 60 (20%) an endovascular, and 29 (10%) a hybrid procedure. Those living >100 miles away less commonly underwent an endovascular procedure (14% vs. 24%, P = 0.05). LOS was similar between near and far groups (7.3 vs. 8.9 days, P = 0.1), as was postoperative functional status (ambulatory 73% vs. 68%, P = 0.34) and discharge to home (68% vs. 74%, P = 0.34). Long-term follow-up (mean 2.07 years) was similar between distance groups (P = 0.6). Five-year AFS (73% vs. 56%, P = 0.02) was superior in the distance >100 group. In the multivariate analysis, distance >100 miles (hazard ratio [HR] 0.6, P = 0.05), preoperative warfarin use (HR 0.5, P = 0.02), and independent ambulatory status (HR 0.5, P = 0.002) were associated with improved AFS. CONCLUSIONS: Patient referral distance did not adversely affect AFS or long-term follow-up after revascularization for CLI. Patients traveling from rural settings for revascularization can expect similar outcomes as patients located near tertiary centers.

Resection of a Large Innominate Vein Aneurysm in a Patient with Neurofibromatosis Type 1.

BACKGROUND: Venous aneurysms are exceedingly rare manifestations of neurofibromatosis type 1 (NF1). There are only a handful of cases reported, and no prior cases describing treatment of mediastinal venous aneurysms in this patient population exist. CASE REPORT: A 58-year-old woman with NF1 presented with a right neck mass. The mass had recently doubled in size and was associated with cough, hoarseness of voice, and pain. Her pertinent medical history included untreated obstructive sleep apnea, severe pulmonary hypertension, and a recent hospital admission for pneumonia. On physical examination, numerous cutaneous neurofibromas were noted. The mass encompassed her right neck and supraclavicular area with marked respiratory variation. Computed tomography showed a complex 7-cm venous aneurysm including her right innominate, internal jugular, and subclavian veins. Surgical approach involved median sternotomy with right cervical extension and a right infraclavicular counter incision. Extracorporeal circulation was established through the left groin. Ligation of the right internal jugular vein was required. The aneurysm was completely excised, and venous reconstruction consisted of cryopreserved femoral vein anastomosed to right innominate and infraclavicular subclavian veins. Intraoperatively, her preexisting pulmonary hypertension resulted in acute right heart failure requiring placement of a right ventricular assist device (RVAD). She subsequently returned to the operating room for RVAD weaning and sternal closure. Her postoperative course was lengthy; however, many of her aneurysm-related symptoms resolved. CONCLUSIONS: This case represents management of the only innominate vein aneurysm in the setting of NF1 described in the literature. Vascular reconstruction is possible, however difficult. Careful preoperative planning and use of extracorporeal circulation was necessary in this case.

Using implementation science to help integrate preoperative evidence-based measures into practice for vascular surgery patients.

The preoperative workup is a necessary and crucial evaluation for patients undergoing major vascular surgery. It is important to assess for likelihood of perioperative adverse events and then implement evidence-based measures to reduce identified medical comorbidities and improve the quality of patient care and outcomes after surgery. Although there are numerous opportunities to implement evidence-based processes during the preoperative period, there are many barriers that can prevent vascular surgeons from achieving these goals. This review will discuss how an implementation science-based approach can be used by members of the vascular surgery team to identify appropriate preoperative evidence-based interventions for diverse practice settings and to overcome barriers and allow integration of these interventions as part of the routine preoperative workup.

Assessment of polyelectrolyte coating stability under dynamic buffer conditions in CE.

Dynamic buffer conditions are present in many electrophoretically driven separations. Polyelectrolyte multilayer coatings have been employed in CE because of their chemical and physical stability as well as their ease of application. The goal of this study is to measure the effect of dynamic changes in buffer pH on flow using a real-time method for measuring EOF. Polyelectrolyte multilayers (PEMs) were composed of pairs of strong or completely ionized polyelectrolytes including poly(diallyldimethylammonium) chloride and poly(styrene sulfonate) and weak or ionizable polyelectrolytes including poly(allylamine) and poly(methacrylic acid). Polyelectrolyte multilayers of varying thicknesses (3, 4, 7, 8, 15, or 16 layers) were also studied. While the magnitude of the EOF was monitored every 2 s, the buffer pH was exchanged from a relatively basic pH (7.1) to increasingly acidic pHs (6.6, 6.1, 5.5, and 5.1). Strong polyelectrolytes responded minimally to changes in buffer pH (<1%), whereas substantial (>10%) and sometimes irreversible changes were measured with weak polyelectrolytes. Thicker coatings resulted in a similar magnitude of response but were more likely to degrade in response to buffer pH changes. The most stable coatings were formed from thinner layers of strong polyelectrolytes.