Adam H. Power

Similar failure and patency rates when comparing one- and two-stage basilic vein transposition

OBJECTIVE Basilic vein transposition is recommended in patients who are not candidates for a radial or brachial artery to cephalic vein fistula for dialysis access. Both one-stage and two-stage procedures have their advantages and disadvantages. Which procedure results in improved outcomes remains unclear. METHODS A systematic review was conducted of the MEDLINE and EMBASE databases for studies that compared one-stage and two-stage brachial-basilic vein transpositions. Abstracts and full-text studies were screened independently by two reviewers with data abstraction done in duplicate. Random-effects meta-analysis was used to identify differences in primary failure rates and 1-year primary and secondary patency rates. Study quality was assessed by a previously described tool designed for observational studies reporting on dialysis access outcomes. RESULTS Of 1662 abstracts screened, 97 were selected for full-text review. Of these, eight studies (one randomized trial, seven observational studies) involving 882 patients met the inclusion criteria. The pooled odds ratio estimate for primary failure was 1.21 (95% confidence interval [CI], 0.73-1.98; P = .46), suggesting no difference in failure rate between one-stage and two-stage transpositions. Similarly, the estimated odds ratio for 1-year primary patency rate of 1.39 (95% CI, 0.71-2.72; P = .33) and 1-year secondary patency rate of 1.02 (95% CI, 0.36-2.87; P = .98) indicated no difference between the two groups. Study quality was limited by unclear outcome definitions, minimal control for confounding, and variable selection criteria. The decision to pursue a one-stage vs a two-stage procedure was often based on size of the basilic vein, with a two-stage procedure reserved for patients with smaller veins. CONCLUSIONS Meta-analysis of the existing literature comparing one-stage and two-stage basilic vein transposition suggests no difference in failure and patency rates, despite the two-stage procedures being used in patients with smaller basilic veins. These findings are limited by the small size, observational design, and inconsistent quality of included studies. Reserving a two-stage procedure for patients with smaller basilic veins appears justified, although the strength of the evidence is limited.

Durability and survival are similar after elective endovascular and open repair of abdominal aortic aneurysms in younger patients.

OBJECTIVE The role of endovascular repair (EVAR) of aortic aneurysms in young patients is controversial. The purpose of this study was to determine the long-term outcomes and reintervention rates in patients 60 years of age or younger who underwent elective open or endovascular repair of an abdominal aortic aneurysm. METHODS Retrospective review of a prospectively collected vascular surgery database at a university-affiliated medical center was performed to identify all patients who underwent elective repair of an abdominal aortic aneurysm between 2000 and 2013 and were 60 years of age or younger at the time of the repair. Preoperative anatomic measurements were performed and compared with instructions for use (IFU) criteria for the endografts. RESULTS The study cohort comprised 169 patients 60 years of age or younger (mean age, 56.7 ± 2.8 years) who underwent elective repair (119 open repair, 50 EVAR). Patients treated with open repair and EVAR had similar comorbidities, except that EVAR patients were more likely to have hypertension (P = .03) and poor left ventricular function (P = .04). The open repair group had significantly larger suprarenal (P = .004) and infrarenal (P = .005) neck angles, shorter neck lengths (P < .001), and larger maximum aneurysm diameter (P = .02) compared with the EVAR group. Only five patients (13%) in the EVAR group did not meet all IFU criteria. The overall in-hospital mortality rate was 1.8% (0% EVAR, 2.5% open repair; P = .56). Overall mean life expectancy was 11.5 years (9.8 years EVAR, 11.9 years open repair; P = .09). The 1-year (98% EVAR, 96% open repair), 5-year (86% EVAR, 88% open repair), and 10-year (54% EVAR, 75% open repair) survival did not differ between EVAR and open repair (P = .16). Long-term survival (78% EVAR, 85% open repair; P = .09) and reintervention rates (12% EVAR, 16% open repair; P = .80) did not differ. No late aneurysm rupture or aneurysm-related deaths were observed. The most common causes of long-term mortality were malignant disease and cardiovascular events. Reinterventions in the open repair group were exclusively laparotomy related (incisional hernia repairs), whereas all reinterventions in the EVAR group were aortic related, including one conversion to open repair. CONCLUSIONS After elective aneurysm repair, younger patients have a moderate life expectancy related to malignant disease and cardiovascular health. EVAR offers durability and long-term survival similar to those with open repair in these younger patients as long as aneurysm anatomy and IFU are adhered to.

Fibrinogen Level and Bleeding Risk During Catheter-Directed Thrombolysis Using Tissue Plasminogen Activator.

Purpose: The purpose of this study was to determine whether low fibrinogen levels (fibrinogen level <1.5 g/L) during catheter-directed thrombolysis are associated with an increased bleeding risk. Methods: A retrospective review was performed on patients undergoing extremity arterial or venous thrombolysis between 2005 and 2013. Results: Patients in the low fibrinogen group were younger (P = .006) and had a higher number of venous occlusive events (P = .004). The low fibrinogen group received a larger dose of tissue plasminogen activator (tPA; P = .009) and had a longer duration of thrombolysis (P = .010). The rates of major bleeding were not significantly different (P = .139). Univariate analysis showed that larger total dose and longer duration of tPA infusion were associated with increased bleeding complications (P < .01 and P = .03). Conclusion: A fibrinogen level <1.5 g/L during thrombolysis was not associated with an increased bleeding risk. However, larger dose and longer duration of thrombolysis were associated with increased bleeding risk.

Anatomy of the nerves and ganglia of the aortic plexus in males

It is well accepted that the aortic plexus is a network of pre‐ and post‐ganglionic nerves overlying the abdominal aorta, which is primarily involved with the sympathetic innervation to the mesenteric, pelvic and urogenital organs. Because a comprehensive anatomical description of the aortic plexus and its connections with adjacent plexuses are lacking, these delicate structures are prone to unintended damage during abdominal surgeries. Through dissection of fresh, frozen human cadavers (n = 7), the present study aimed to provide the first complete mapping of the nerves and ganglia of the aortic plexus in males. Using standard histochemical procedures, ganglia of the aortic plexus were verified through microscopic analysis using haematoxylin & eosin (H&E) and anti‐tyrosine hydroxylase stains. All specimens exhibited four distinct sympathetic ganglia within the aortic plexus: the right and left spermatic ganglia, the inferior mesenteric ganglion and one previously unidentified ganglion, which has been named the prehypogastric ganglion by the authors. The spermatic ganglia were consistently supplied by the L1 lumbar splanchnic nerves and the inferior mesenteric ganglion and the newly characterized prehypogastric ganglion were supplied by the left and right L2 lumbar splanchnic nerves, respectively. Additionally, our examination revealed the aortic plexus does have potential for variation, primarily in the possibility of exhibiting accessory splanchnic nerves. Clinically, our results could have significant implications for preserving fertility in men as well as sympathetic function to the hindgut and pelvis during retroperitoneal surgeries.

Determination of Patient Preference for Location of Elective Abdominal Aortic Aneurysm Surgery

Objective: Aneurysm repair is centralized in higher volume centers resulting in reduced mortality, with longer travel distances. The purpose of this study is to explore patients’ preference between local care versus longer distances and lower mortality rates. Methods: Patients with abdominal aortic aneurysm (AAA) measuring 4 to 5 cm and living at least a 1-hour drive from our hospital were asked to assume it had grown to 5.5 cm, and repair was recommended with a mortality risk of 2%. The level of additional risk they would accept to undergo surgery locally was determined. Results: A total of 67 patients were surveyed. If mortality risk was equivalent at the local and regional hospitals, 44% preferred care at our tertiary center, while 56% preferred surgery locally. If perioperative mortality was increased at the local hospital, 9% preferred local surgery. Conclusions: The vast majority of patients with AAA will accept longer travel distances for care as long as it results in a reduction in perioperative mortality.

Endograft conformability and aortoiliac tortuosity in endovascular abdominal aortic aneurysm repair.

Purpose To determine conformability of stent-grafts in endovascular aneurysm repair (EVAR) using centerline of flow measurements and to compare conformability in patients with severe aortoiliac tortuosity. Methods From 2012 to 2013, 111 consecutive patients (98 men; mean age 75.4±7.7 years) underwent endovascular aneurysm repair with Endurant I and II and Zenith Flex, LP, and Spiral Z stent-grafts; their pre- and post-EVAR computed tomography (CT) studies were retrospectively analyzed using quantitative 3-dimensional imaging software. The length between the lowest renal artery and the iliac bifurcation was measured using centerline of flow and was defined as the treatment length (TL). The difference in TLs pre and post EVAR were compared as a surrogate to evaluate endograft conformability. Results A total of 203 pre and post EVAR aortoiliac TLs were measured (99 Endurant I, 20 Endurant II, 32 Flex, 6 LP, and 42 Spiral Z). Overall, there was a mean difference of 5.0±7.3 mm or 2.6%±3.9% between the pre- and post-EVAR TLs (p<0.001). No statistically significant difference in TLs was observed among the various stent-grafts (p=0.115). In 40 patients with severe aortoiliac tortuosity, the post-EVAR TL was 16.2±5.5 mm or 8.0%±2.7% shorter than the pre-EVAR TL (p<0.001); again, there was no difference in TLs among the various devices implanted (p=0.737). Conclusion Overall, there was no difference in treatment lengths before and after EVAR among different stent-grafts, suggesting similar conformability. Interestingly, patients with severe aortoiliac tortuosity were found to have significantly shorter post-EVAR treatment lengths compared to before EVAR, which should be considered when planning EVAR.

Two Cases of Transcutaneous Electrical Nerve Stimulation of the Common Peroneal Nerve Successfully Treating Refractory, Multifactorial Leg Edema

The treatment of leg edema often involves promoting venous blood flow but can be difficult in patients with comorbidities that prevent traditional management strategies such as limb elevation or mechanical compression devices. The geko device is a self-contained neuromuscular stimulation device that adheres to skin over the common peroneal nerve and delivers a low-voltage stimulus that activates the lower-leg musculature resulting in enhanced superficial femoral vein blood flow and velocity. Here we report 2 cases of multifactorial and refractory leg edema successfully treated with the geko device over a period of 4 to 16 weeks. The device also improved pain and chronic wound healing. Although the geko device is costly, it was well tolerated and may provide another treatment strategy for resistant leg swelling.

Randomized clinical trial of negative pressure wound therapy for high-risk groin wounds in lower extremity revascularization

Objective: The surgical site infection (SSI) rate in vascular surgery after groin incision for lower extremity revascularization can lead to significant morbidity and mortality. This trial was designed to study the effect of negative pressure wound therapy (NPWT) on SSI in closed groin wounds after lower extremity revascularization in patients at high risk for SSI. Methods: A single‐center, randomized, controlled trial was performed at an academic tertiary medical center. Patients with previous femoral artery surgical exposure, body mass index of >30 kg/m2 or the presence of ischemic tissue loss were classified as a high‐risk patient for SSI. All wounds were closed primarily and patients were randomized to either NPWT or standard dressing. The primary outcome of the trial was postoperative 30‐day SSI in the groin wound. The secondary outcomes included 90‐day SSI, hospital duration of stay, readmissions or reoperations for SSI, and mortality. Results: A total of 102 patients were randomized between August 2014 and December 2015. Patients were classified as at high risk owing to the presence of previous femoral artery cut down (29%), body mass index of >30 kg/m2 (39%) or presence of ischemic tissue loss (32%). Revascularization procedures performed included femoral to distal artery bypass (57%), femoral endarterectomy (18%), femoral to femoral artery crossover (17%), and other procedures (8%). The primary outcome of 30‐day SSI was 11% in NPWT group versus 19% in standard dressing group (P = .24). There was a statistically significant shorter mean duration of hospital stay in the NPWT group (6.4 days) compared with the standard group (8.9 days; P = .01). There was no difference in readmission or reoperation for SSI or mortality between the two groups. Conclusions: This study demonstrated a nonsignificant lower rate of groin SSI in high‐risk revascularization patients with NPWT compared with standard dressing. Owing to a lower than expected infection rate, the study was underpowered to detect a difference at the prespecified level. The NPWT group did show significantly shorter mean hospital duration of stay compared with the standard dressing group.

Explaining endograft shortening during endovascular repair of abdominal aortic aneurysms in severe aortoiliac tortuosity.

Objective: During endovascular aneurysm repair (EVAR), severely tortuous aortoiliac anatomy can alter the deployment and conformability of the endograft. The accuracy of treatment length measurements is commonly recognized to be affected by severe tortuosity. However, the exact mechanism of the postintervention length discrepancy is poorly understood. The objective of this study was to determine the mechanism of how severe aortoiliac tortuosity influences the endograft and native aorta during EVAR and its impact on the distal sealing zone. Methods: A prospectively collected vascular surgery database was retrospectively reviewed at a university‐affiliated medical center to identify the study patients. Patients who underwent EVAR with the main body device deployed on the side of the severely tortuous iliac artery were selected. Severe aortoiliac tortuosity was defined as having either aortoiliac or common iliac angulation <90 degrees. Results: A total of 469 patients between 2008 and 2014 underwent EVAR using the Endurant endograft (Medtronic Cardiovascular, Santa Rosa, Calif). Severe aortoiliac tortuosity was observed in 36% of patients; 17 patients were found to have the main body placed on the side of severe tortuosity without an extension limb. There was a significant shortening of the main body endograft length from 169 mm before EVAR to 147 mm after EVAR (P < .001). The treatment length of the main body, measured from the lowest renal artery to hypogastric artery, also significantly shortened from 179 mm to 170 mm (P < .001). There was a decrease in tortuosity at the most angulated portion of the aneurysm after EVAR, in which angulation changed from 86 degrees to 114 degrees (P < .001). There was no significant change in treatment length (P = .859) and angulation (P = .195) on the nontortuous side of the aneurysm. Conclusions: The study observed significant shortening of endografts and native aorta and iliac arteries in patients with severe aortoiliac tortuosity during EVAR. This shortening effect can have a negative impact on the distal sealing zone during EVAR. A longer main body or an extension limb should be considered when one is faced with severely tortuous aneurysms.

Bedside identification of blunt thoracic aortic injury with point-of-care transesophageal echocardiography

Trauma point-of-care ultrasound in the form of the Focused Assessment with Sonography for Trauma (FAST) exam and its evolution into extended FAST have significantly enhanced the diagnostic power of evaluation and resuscitation of the trauma patient; however, these modalities still have limitations in evaluating mediastinal and cardiac pathology. This report demonstrates a case of point-of-care transesophageal echocardiography in the diagnosis of blunt thoracic aortic injury in an unstable patient involved in a motor vehicle collision.