Anesthesia technique and outcomes of endovascular aneurysm repair.

Anesthetic techniques vary widely in the endovascular repair of abdominal aortic aneurysms (EVAR). Previous studies have demonstrated the feasibility of using local anesthesia. However, the ideal anesthetic technique has not been determined. This study examines whether anesthetic technique influences the outcomes of EVAR. Data regarding demographics, risk factors, procedural characteristics, recovery characteristics, treatment complications, acute (<30 day) medical complications, mortality, and anesthetic type were prospectively collected during the AneuRx phase II aortic endograft trial. Patient cohorts receiving general, regional, or local anesthesia were compared. From 1997 to 1998, 424 patients underwent EVAR at 13 sites using the AneuRx Bifurcated endograft. There were 279 patients in the general anesthesia group, 95 patients in the regional group, and 50 patients in the local group. Risk factors were similar. There were no significant differences in age, gender, American Society of Anesthesiologists grade, length of anesthesia, branch artery occlusions, proximal endoleaks, failed implants, or open surgical conversions. Cardiac, renal, and wound-healing complications were all lower in the local group. Mortality was equivalent among the three groups. (p > 0.05, ANOVA). From these results we concluded that EVAR with local anesthesia is a safe and efficacious method that may reduce recovery times and postoperative medical morbidity compared to use of general or spinal/epidural anesthesia.

Pitfalls in achieving the Dialysis Outcome Quality Initiative (DOQI) guidelines for hemodialysis access?

The Dialysis Outcome Quality Initiative (DOQI) mandates that 50% of permanent hemodialysis (HD) access be native arteriovenous fistulae (AVFs). Recent reports have shown that when these guidelines are followed, the percentage of new AVFs can exceed DOQI guidelines. From July 1998 to July 2001, 330 HD access procedures were performed in an academic tertiary care center. Patients were categorized into two groups. Group I followed DOQI guidelines and underwent history and physical examination; duplex vein mapping; use of basilic vein transposition; and a postoperative protocol to determine maturation and start needle access in a stepwise progression. Group II had history and physical examination and basilic vein transposition was not used. Patient data were retrospectively reviewed. Overall, 100 (31%) HD shunts were AVFs. Group I (42/183, 23%) had significantly less AVFs (p = 0.005) than group II (58/147, 39%). For first-time placement of HD access, there was no significant difference (p = 0.95) in the percentage of AVFs in group I (26/62, 42%) and group II (29/68, 43%). For patients with prior history of HD access, significantly less AVFs (p <0.001) were placed in group I (16/121, 13%) than in group II (29/79, 37%). Group I had significantly less first-time HDS (P = 0.03) than group II, 34% VS. 46%, respectively. AVF maturation for hemodialysis occurred in 79% of group I and 71% of group II (P = 0.52). There were no significant differences (P > 0.05) when comparing age, gender, and incidence of diabetes between the two groups. AVF formation based largely on duplex vein mapping in group I and lack of basilic vein transposition in group II contributed to the inability to achieve DOQI guidelines. Integration of knowledge and practice among vascular surgeons may help to avoid these pitfalls.

Selective venography versus nonselective venography before vena cava filter placement: evidence for more, not less.

OBJECTIVE: We undertook this study to determine whether additional use of selective venography, compared with nonselective venography alone, reveals more abnormal anatomic venous findings that lead to changes in vena cava filter (VCF) position. METHODS: From January 1998 to June 2002, 94 patients underwent VCF placement by vascular surgeons at a university tertiary care center. Indications, techniques, decision analysis, and complications were reviewed. Nonselective venography and selective venography of the inferior vena cava (IVC) were evaluated for image quality, abnormal findings, aberrant anatomy, and the anatomic relationship of vertebral bodies to major venous tributaries. RESULTS: Absolute and relative indications for VCF placement were 44% and 56%, respectively. Jugular, femoral, and subclavian vein approach was used in 47%, 47%, and 6% of patients, respectively. Seventy-three percent of VCFs were placed in the catheterization laboratory, 21% in the operating room, and 5% at the bedside. Nonselective venography was performed in 80 patients (85%), of whom 44% had undergone selective venography. At nonselective venography plus selective venography 7.5% of patients had an abnormal finding (IVC compression, n = 3; IVC thrombus, n = 2; tortuosity, n = 1). Similarly, 17.5% of patients had aberrant anatomy (accessory renal vein, n = 8; IVC duplication, n = 3; large low right gonadal vein, n = 2; megacava, n = 2). Nonselective venography plus selective venography demonstrated that 16% of VCFs required a major change in position, 10% of which were placed above the renal veins. Compared with nonselective venography alone, selective venography enabled detection of significantly more abnormal and aberrant findings (9% vs 49%; P <.001). Changes in VCF placement were necessary significantly more often in patients undergoing additional selective venography compared with nonselective venography alone (31% vs 4%; P =.003). In one patient in the series, a VCF was malpositioned in the iliac vein with intravascular ultrasound visualization. CONCLUSION: When nonselective venography plus selective venography were performed, 23% of patients had either an abnormal finding or aberrant anatomy, and most of these required a major change in VCF position. Nonselective venography plus selective venography redefines the criterion standard and, because of limitations of other methods of vena cava visualization for VCF deployment, should be performed in most patients.

Indications and outcomes of AneuRx Phase III trial versus use of commercial AneuRx stent graft.

OBJECTIVE: Approval by the United States Food and Drug Administration of endoluminal repair of abdominal aortic aneurysm (AAA) with the AneuRx stent graft was based on the outcome of a multicenter trial in which patients met strict inclusion and exclusion criteria. Since widespread use of the commercially available graft, little information is available as to whether indications and outcomes have evolved. We examined this important issue at our institution. METHODS: Data concerning indications, repair, and follow-up for all patients undergoing endoluminal repair of AAA was prospectively entered into a patient registry. Group 1 comprised consecutive patients enrolled in the AneuRx Phase III clinical trial between November 1998 and September 2000. Group 2 consisted of consecutive patients who underwent implantation of the commercially available AneuRx graft between May 1999 and June 2001. RESULTS: Group 1 included 42 patients (mean age, 72 years), and group 2 included 54 patients (mean age, 73 years). Patient demographics and risk factors were similar between the two groups. Maximum aortic aneurysm diameter was significantly greater (P =.021) in group 1 (55 mm +/- 10.9 [SD] mm) compared with group 2 (52 +/- 15.6 mm). Maximum infrarenal aortic neck length was significantly longer (P =.022) in group 1 (30 +/- 11.7 mm) than in group 2 (23 +/- 12.0 mm). Maximum left common iliac artery diameter in group 1 (13.0 +/- 3.2 mm) was significantly smaller (P =.032) than that in group 2 (14 +/- 6.5 mm). During follow-up, no differences were observed for number of endoleaks, subsequent interventions, or graft explantation between the two groups. CONCLUSIONS: In group 2 patients AAAs were significantly smaller, infrarenal aortic neck length was shorter, and left common iliac arteries were larger. Common iliac artery ectasia and aneurysmal disease has become another indication for use of the AneuRx commercial graft at our institution, with no significant differences in intermediate outcome. Given the possibility for evolving indications compared with trial inclusion and exclusion criteria, institutions that use the AneuRx commercial graft should prospectively monitor outcomes for quality assurance.

Mechanism of failure in the treatment of type II endoleak with percutaneous coil embolization.

PURPOSE: Type II endoleak after endovascular abdominal aortic aneurysm repair is a failure of aneurysm sac exclusion with unknown long-term consequences. Elevated aneurysm sac pressures documented in these patients have led us to aggressively treat type II endoleaks with percutaneous transluminal coil embolization (PTCE). The purpose of this study was to evaluate the results and the mechanisms of failure of PTCE for type II endoleak. METHODS: One hundred ninety-one patients underwent endograft repair of infrarenal aortic aneurysms. Twenty-three of 28 patients with persistent primary (>3 months) or secondary (new-onset) endoleak underwent angiography; 14 of these patients had type II endoleaks. We reviewed our endovascular registry data, hospital charts, and radiologic studies of patients with type II endoleaks and analyzed the results in those treated with PTCE of the inflow vessel. RESULTS: All 14 patients with type II endoleaks were men, with a mean age of 76.7 years and a mean preoperative maximal aneurysm diameter of 5.7 +/- 1.0 cm. The type II endoleak was primary in 12 patients (86%) and secondary in two patients (14%) and iliolumbar in 11 patients (78%) and mesenteric in three patients (21%). Although a dominant affluent collateral channel (inosculation) was apparent in eight patients (57%), six patients (43%) showed a network of collateral vessels (retiform anastomosis). In six patients (43%), angiography revealed a second or "outflow" vessel indicative of a complex endoleak. In four patients with retiform iliolumbar type II endoleaks, PTCE was not attempted because of the retiform nature of the endoleak. The remaining 10 patients underwent PTCE, with coil deployment in all 10 and apparent initial technical success in nine patients. Follow-up computed tomographic scans revealed persistent endoleaks in six patients (60%). Mechanisms of failure included persistent flow through the coils in the treated vessel in two patients, development of a retiform anastomosis around the coiled vessel in three patients, and development of a new mesenteric endoleak after successful occlusion of an iliolumbar endoleak in one patient. Two patients underwent repeat PTCE with successful aneurysm sac exclusion in one. Internal iliac artery injury complicated one of the 12 PTCEs, and the resulting pseudoaneurysm was successfully treated with PTCE. Angiographic visualization of an outflow vessel (complex endoleak) was associated with PTCE failure (P =.008). CONCLUSION: PTCE of type II endoleaks has a high failure rate because of multiple anatomic mechanisms.

Retrograde endovascular hypogastric artery preservation (REHAP) and aortouniiliac (AUI) endografting in the management of complex aortoiliac aneurysms.

The preservation of internal iliac artery (IIA) flow during endovascular repair of abdominal aortic aneurysms (er-AAA) remains a controversial area. Ectasia and aneurysmal disease of the iliac arteries represent a formidable challenge to the endovascular surgeon, particularly when aortic neck length and diameter are suitable for er-AAA. We describe a procedure to maintain arterial perfusion to the pelvis during er-AAA called retrograde endovascular hypogastric artery preservation (REHAP). This technique is particularly useful in the presence of common iliac artery (CIA) and internal iliac artery (IIA) aneurysms when pelvic perfusion to one IIA needs to be maintained. A Wallgraft is first placed from the IIA to the ipsilateral EIA followed by er-AAA using an aortouniiliac graft (AUI) and a femorofemoral bypass graft (BPG). This procedure represents one alternative to maintaining pelvic perfusion using standard endovascular and surgical techniques.