Good outcomes for arteriovenous fistula with buttonhole cannulation for chronic hemodialysis in children and adolescents.

BACKGROUND: Arteriovenous fistula (AVF) is the preferred access for chronic hemodialysis (HD) in children and adolescents, but central venous catheter use is still high. METHODS: Retrospective chart review of children and adolescents with AVF created between January 2003 and December 2015 was performed to assess primary failure (PF), maturation time, functional primary and functional cumulative patency, and potential risk factors for AVF dysfunction. RESULTS: Ninety-nine AVF were created in 79 patients (54% male; 7-24 years; 16-147 kg) by experienced surgeons. Duplex ultrasonography vein mapping was used to assist with site selection. PF occurred in 17 AVF (17%) in 14 patients. Patient age, gender, ethnicity, underlying disease, time on dialysis, and AVF site were not associated with PF or patency. Coagulation abnormality was positively associated with PF (p = 0.03). Function was achieved in 82 AVF (83%) in 77 patients (97%). Median maturation time was 83 days (range 32-271). AVF were accessed via buttonholes. Functional primary patency was 95%, 84%, and 53% at 1, 2, and 5 years. Overall 1- and 2-year functional cumulative patency was 95%, but lower for small patients 16-30 kg (88%) and those greater than 80 kg (91%). The 5-year patency rate was 80%, but significantly lower for 16-30 kg (59%) and greater than 80 kg (55%). Risk analysis showed significantly better patency for 31-45 kg and 46-80 kg groups (p < 0.01), non-obese BMI (p = 0.01), and buttonhole self-cannulation (p = 0.03). CONCLUSIONS: This study provides more information about successful AVF with buttonhole cannulation in pediatric hemodialysis patients lending additional support for AVF use in pediatrics. A higher resolution version of the Graphical abstract is available as Supplementary information.

Imaging work-up and endovascular treatment options for aorto-enteric fistula.

Aorto-enteric fistula (AEF) is a rare life-threatening condition. Early recognition and diagnosis are of paramount importance to improve outcome. In this article four cases of AEF with relevant pre- and post-procedural images are presented to demonstrate the utility of cross-sectional imaging in the work-up of AEF. The literature is reviewed to describe the typical presentation of AEF, the diagnostic work-up of AEF, and the different methods used to treat AEF. Endovascular repair of AEF is gaining increasing attention due to its decreased short-term mortality compared to open surgical techniques.

Nonmaturing Fistulae: Epidemiology, Possible Interventions, and Outcomes.

Autogenous arteriovenous fistulae are the best method for prolonged, successful dialysis access. However, a substantial limitation of dialysis fistulae is their high primary failure rate, estimated to be as high as 70% for radiocephalic fistulae. Fistula maturation is influenced by demographic risk factors as well as anatomical barriers, the latter of which can be readily identified by noninvasive ultrasound imaging and physical examination. These barriers can be categorized as inflow problems (native arterial disease, arteriovenous anastomotic stenosis, and juxta-anastomotic stenosis) or outflow problems (proximal venous stenosis or collateral veins). Venous stenoses represent the most commonly observed barrier to fistula maturation. By treating these barriers with a systematic approach, interventionalists can significantly improve the likelihood of a fistula's usability for dialysis.

Limb salvage in women.

The prevalence of peripheral arterial occlusive disease (PAD) in women and men is equal. Studies to date present conflicting data of gender effects on the risk factors, clinical presentation, and treatment outcomes. Clinical trials have often failed to analyze results by gender or to recruit sufficient women to enable such an analysis. This review summarizes the management and outcome of limb salvage therapy with a particular focus in women.

Hybrid interventions in limb salvage.

Hybrid interventions have become an integral part of our strategy for limb salvage in patients with multilevel arterial occlusive disease. In this article, we describe the commonly used hybrid interventions and review their indications and outcomes. Iliac stenting and femoral endarterectomy are the two most frequently performed procedures in hybrid cases. Short- and long-term outcomes of hybrid interventions are at least comparable to conventional endovascular and surgical revascularization procedures. Hybrid revascularization offers the efficiency and convenience of a single-stage revascularization.

Diseases of the thoracic aorta in women.

Women have now equaled or surpassed men in the number of cardiovascular deaths per year in published statistics. In 2006, according to the National Center for Health Statistics and the Center for Disease Control, cardiovascular disease was the cause of death in 428,906 women (35% of all deaths in women) and in 394,840 men (33% of all deaths in men). Of those numbers, it was estimated that 5506 women (0.4% of all deaths in women) and 7732 men (0.6%) died because of aortic aneurysm or dissection. Currently, aortic disease ranks as the 19th leading cause of death with reported increases in incidence. Historically, aortic disease is thought to affect men more frequently than women with a varying reported gender ratio. Gender bias has long been implicated as an important factor, but often overlooked, in the analysis and interpretation of cardiovascular diseases outcome, in part, because of the under-representation of women in clinical trials and studies. In this section, we provide an up-to-date review of the epidemiology and management of common diseases of the thoracic aorta, focusing on the differences and similarities in women and men.

Multilevel somatosensory evoked potentials and cerebrospinal proteins: indicators of spinal cord injury in thoracoabdominal aortic aneurysm surgery.

OBJECTIVE: Multilevel somatosensory evoked potentials (SSEP) and the release of biochemical markers in cerebrospinal fluid (CSF) were investigated to identify patients with spinal cord ischemia during thoracoabdominal aortic repair and/or a vulnerable spinal cord during the postoperative period. METHODS: Thirty-nine consecutive patients undergoing elective aneurysm repair using distal aortic perfusion and cerebrospinal fluid drainage were studied. Continuous SSEP were monitored using nerve stimulation of the right and left posterior tibial nerves with signal recording at the level of both common peroneal nerves, the cervical cord and at the cortical level. CSF concentrations of the markers glial fibrillary acidic protein (GFAp), the light subunit of neurofilament triplet protein (NFL), and S100B were determined at different time points from before surgery until 3 days postoperatively. RESULTS: SSEP indicated spinal cord ischemia in two patients leading to additional intercostal artery reattachments. In one of them the signal loss was permanent and the patient woke up with paraplegia. In the other the signal returned but the patient later developed delayed paraplegia. Three patients without SSEP indications of spinal cord ischemia during surgery later developed delayed paraplegia. The patients with spinal cord symptoms had significant increases, during the postoperative period of CSF biomarkers GFAp (571-fold), NFL (14-fold) and S100B (18-fold) compared to asymptomatic patients. GFAp increased before or in parallel to onset of symptoms in the patients with delayed paraplegia. CONCLUSIONS: Peroperative multilevel SSEP has a high specificity in detecting spinal cord ischemia but does not identify all patients with a postoperative vulnerable spinal cord. Biochemical markers in CSF increase too late for intraoperative monitoring but GFAp is promising for identifying patients at risk for postoperative delayed paraplegia.

Management of distal femoral and popliteal arterial injuries: an update.

BACKGROUND: The management of combined arterial and musculoskeletal injuries to the lower extremity remains controversial, particularly with regard to the initial order of intervention and the use of intravascular shunting. In this study, we review the contemporary management and outcome of patients treated for acute traumatic distal femoropopliteal arterial injuries. METHODS: From January 2001 to January 2006, we repaired 57 acute traumatic lower-extremity arterial injuries in a level 1 trauma center. Our approach was to perform surgical revascularization without intraluminal shunting as soon as the arterial injury was recognized. There were 44 men (77%). Mean age was 31 years (range, 5-68). The mechanism of injury was blunt in 42 of 57 (74%) patients. Vascular reconstruction was achieved by using an autogenous saphenous vein graft in 52 of 57 (91%), a vein patch in 3 of 57 (5%), or primarily in 2 of 57 (4%) patients. RESULTS: The limb-salvage rate was 92% (53/57). Thirty-six patients (63%) had associated orthopedic fixation: 12 of 36 (33%) before and 24 of 36 (67%) after revascularization. Twenty-one of 57 patients (37%) had vascular repair only without orthopedic fixation. Thirty-four patients (60%) required fasciotomy. Four patients had subsequent above-knee amputation: 3 because of wound complications despite successful revascularization and 1 because of failed revascularization. There were no complications related to the arterial repairs that were performed before orthopedic fixation. CONCLUSION: Our study shows that arterial reconstruction for acute traumatic lower-limb injuries results in a good limb-salvage rate. We advocate prompt vascular repair before orthopedic intervention for combined vascular and skeletal injuries of the lower extremity, without using intravascular shunting.

Robotic replacement of the descending thoracic aorta: an alternative to endovascular therapy?

BACKGROUND: : Replacement of the descending thoracic aorta is traditionally performed via a left thoracotomy. Endovascular treatment of descending thoracic aortic aneurysms has recently evolved as an alternative treatment for selected patients, yet no long-term results are available. The authors replaced the descending thoracic aorta in a group of pigs with an interposition Dacron graft using a closed-chest, totally robotic technique. METHODS: : Ten pigs, weighing 25 to 45 kg, underwent surgery using the DaVinci robotic surgical system. Under single-lung ventilation and CO2 insufflation, the descending thoracic aorta was completely mobilized. Proximal and distal cross-clamps were applied through separate accessory stab wounds. The mid-descending thoracic aorta was excised. An interposition Dacron graft was robotically sewn in an end-to-end fashion to the descending thoracic aorta using interrupted nitinol clips. RESULTS: : All animals survived the procedure. Mean aortic clamp time was 55 ± 14 minutes. All anastomoses were completed without difficulty with a mean total anastomotic time of 42 ± 11 minutes. The anastomoses were challenged for bleeding by administrating α1-adrenergic receptor agonists to a systolic blood pressure of 200 mm Hg with no evidence of leak. DISCUSSION: : Robotic replacement of the thoracic aorta is feasible and reproducible. This procedure provides the standard Dacron graft repair with its known long-term results. The added value of robotic technology to the therapeutic armamentarium in the treatment of thoracic aortic aneurysms may be worth the effort required for procedural development. Furthermore, it may serve as a valid alternative to endovascular treatment of thoracic aortic aneurysms.

Surgical repair of extensive aortic aneurysms.

We present our 14-year experience in the management of extensive aortic aneurysms. Significant progress has been made in reducing the morbidity and mortality associated with these procedures. Our strategies for organ protection, operative techniques, including the elephant trunk technique, and surgical results are discussed.

Glomerular filtration rate is superior to serum creatinine for prediction of mortality after thoracoabdominal aortic surgery.

BACKGROUND: Clinically evident renal disease (dialysis, history of renal insufficiency, or serum creatinine >2.0 mg/dL) is a known risk factor for mortality after thoracoabdominal aortic aneurysm repair. We extended this concept to the questions of whether subclinical renal disease is also a risk factor and how best to identify subclinical disease. We hypothesized that the glomerular filtration rate (GFR) would be a more sensitive determinant of renal function than serum creatinine alone. METHODS: Between 1991 and 2004, we repaired 1106 thoracoabdominal aortic aneurysms and descending thoracic aortic aneurysms. The median age was 67 years. There were 400 (36%) women and 706 (64%) men. We estimated GFR by using the Cockcroft-Gault equation. We divided baseline serum creatinine and baseline GFR into quartiles and estimated the association of the quartiles with 30-day postoperative mortality by chi2 testing. We further subdivided the population into patients with and without clinically evident renal disease and repeated the analysis in the patients without clinically apparent disease (n = 869). RESULTS: Clinically apparent renal disease was highly associated with 30-day mortality (odds ratio, 3.2; P < .0001). In all patients, serum creatinine quartile and GFR quartile were also both highly significantly associated with 30-day mortality (P < .0001). In patients without clinically apparent renal disease, both creatinine and GFR predicted additional mortality, but GFR was a much stronger predictor (P < .02 for creatinine vs < .0001 for GFR). In these patients, mortality ranged from 5% in the best GFR quartile to 27% in the worst. Taken as continuous variables in logistic regression equations, serum creatinine had no discrimination in patients without clinical disease (P = .73), whereas GFR remained strong (P < .0001). CONCLUSIONS: Preoperative renal function is an important determinant of early mortality even in patients without clinically evident disease. Estimated GFR is a much more powerful determinant of mortality risk than serum creatinine alone.

Correlations of cerebrospinal fluid pressure with hemodynamic parameters during thoracoabdominal aortic aneurysm repair.

Central venous pressure (CVP) has long been thought to correlate with cerebrospinal fluid (CSF) pressure during thoracoabdominal aortic aneurysm repair. We examined hemodynamic factors during thoracoabdominal aortic aneurysm surgery to determine their relationship with CSF pressure and aortic cross-clamping. Hemodynamic parameters and CSF pressure were measured in 124 patients at six different stages during repair of descending thoracic or thoracoabdominal aortic aneurysms: skin incision, left lung collapse, pump on, aortic clamp on, aortic clamp off, and pump off. Stepwise multiple regression analysis was used for statistical analysis. CVP was a weak predictor for CSF pressure at the beginning of surgery and when the pump was initiated. At the onset of left lung collapse, cardiac output correlated with CSF pressure. There were no predictors during aortic cross-clamping. Model r2 values were low, ranging 0.03-0.15. We found no hemodynamic predictors of CSF pressure throughout the period of aortic cross-clamping during descending thoracic or thoracoabdominal aortic aneurysm surgery. Model r2 values were low, indicating generally poor prediction of CSF pressure.

Cerebral monitoring with transcranial Doppler ultrasonography improves neurologic outcome during repairs of acute type A aortic dissection.

OBJECTIVE: Neurologic complications after repair of acute type A aortic dissection remain significant. The use of power M-mode transcranial Doppler monitoring to verify cerebral blood flow during these repairs might decrease cerebral ischemia by correcting malperfusion. The purpose of this study was to analyze the use of power M-mode transcranial Doppler monitoring during repairs of acute type A dissection with regard to neurologic outcome. METHODS: We performed a prospective study of patients undergoing repairs of acute type A aortic dissection. Repairs included profound hypothermic circulatory arrest and retrograde cerebral perfusion. Patients in whom transcranial Doppler monitoring was used to monitor cerebral blood flow and modify operative technique during repair (study group) were compared with those without monitoring and modification (control group). RESULTS: Between September 2001 and October 2003, we repaired 56 cases of acute type A dissection. Power M-mode transcranial Doppler monitoring was used in 50% (28/56) of cases. Power M-mode transcranial Doppler monitoring altered operative cannulation and guided retrograde cerebral perfusion flow in 28.5% (8/28) and 78.6% (22/28) of cases, respectively. Two patients presented with preoperative stroke, one in each group. One operative death occurred in each group. In-hospital mortality and the occurrence of new stroke were not significantly different between the 2 groups. Temporary neurologic dysfunction occurred less often in the study group (14.8% [4/27] vs 51.8% [14/27], P = .008). CONCLUSIONS: Identification of cerebral malperfusion requires cerebral monitoring. By ensuring cerebral blood flow by using power M-mode transcranial Doppler monitoring and correcting cerebral malperfusion by modifying operative technique, neurologic outcome was improved during repairs of acute type A aortic dissection.

Staged repair of extensive aortic aneurysms: long-term experience with the elephant trunk technique.

OBJECTIVE: This paper reports our experience of a large series of elephant trunk patients accumulated over 12 years. SUMMARY BACKGROUND DATA: Extensive aneurysms of the ascending/arch and descending thoracic or thoracoabdominal aorta are significant surgical problems that have potential for great morbidity. We adopted a staged approach known as the elephant trunk procedure in 1991, and we have used it with some modifications since that time. METHODS: Between February 1991 and December 2003, we performed 1660 operations for ascending/arch or descending thoracic/thoracoabdominal aortic aneurysms. Of these, 321 operations were performed in 218 patients for extensive aneurysms with the elephant trunk technique. We performed 218 ascending/arch repairs and 103 descending thoracic or thoracoabdominal aortic replacements. RESULTS: In 218 ascending/arch repairs, strokes occurred in 3 of 218 (2.7%) patients, with 1 of 187 (0.5%) in the retrograde cerebral perfusion group and 2 of 31 (6.5%) in the no-retrograde cerebral perfusion group (odds ratio 0.08, P < 0.009). Thirty-day mortality for this group was 19 of 218 (8.7%). Among 199 recovering patients after stage 1 repair, 4 of 199 (2%) died during the 30-day to 6-week interval between stages. After stage 2 repair, 0 of 103 patients experienced immediate neurologic deficit, and 10 of 103 (9.7%) died within 30 days of surgery. Actuarial survival after completed stage 2 was 71% at 5 years. CONCLUSION: Despite extreme underlying disease, long-term survival is excellent in patients with extensive aneurysms when both stages of repair are completed. To prevent rupture, the second stage should be completed as soon as the patient's condition permits, preferably within 6 weeks.

Cold visceral perfusion improves early survival in patients with acute renal failure after thoracoabdominal aortic aneurysm repair.

INTRODUCTION: Despite advances in organ protection during thoracoabdominal aortic aneurysm (TAAA) repair, acute renal failure (ARF) remains a significant clinical problem, associated with increased morbidity and mortality. We studied outcome of ARF after TAAA repair in patients who underwent either warm or cold visceral perfusion. METHOD: Between 1991 and 2001 657 TAAA repairs were performed, of which 359 (55%) had either warm or cold visceral perfusion. Twelve patients with renal failure who had undergone preoperative dialysis were excluded from the study. Of the remaining 347 patients, ARF developed in 81 (23%) after TAAA repair. Forty-four (54%) of the 81 patients with ARF received cold visceral perfusion, and 37 (46%) patients received warm visceral perfusion. ARF was defined as either an increase of 1 mg/dL in serum creatinine (SCr) concentration per day for 2 consecutive days or dialysis requirement. Patient records were reviewed through hospital discharge. RESULTS: Twenty six (32%) of the 81 patients in whom ARF developed died, 17 of 37 (46%) patients in the warm perfusion group versus 9 of 44 (21%) patients in the cold perfusion group (P <.02). Median onset of ARF was on postoperative day 1 in both groups. Twenty-six of 81 (32%) patients recovered renal function, 10 of 37 (27%) patients in the warm perfusion group versus 16 of 44 (36%) patients in the cold perfusion group. Preoperative SCr concentration was predictive of recovery of renal function (odds ratio, 4.5 per mg/dL increase; P <.03) in patients who received either warm or cold visceral perfusion. CONCLUSIONS: ARF after TAAA repair remains a significant clinical problem. Recovery of renal function occurred in approximately one third of patients. Preoperative SCr concentration was the only significant determinant of recovered renal function. While cold visceral perfusion did not alter renal recovery, it significantly reduced hospital mortality.

Preoperative and operative predictors of delayed neurologic deficit following repair of thoracoabdominal aortic aneurysm.

PURPOSE: Delayed neurologic deficit has been recognized in recent years as a source of morbidity following thoracic and thoracoabdominal aortic repair. We wanted to find risk factors specifically significant for delayed neurologic deficit. In this initial study we looked at preoperative and operative risk factors. METHODS: We performed 854 thoracoabdominal aortic repairs between February 1991 and May 2001. For this study we excluded 26 patients who died before postoperative neurologic status could be evaluated and 38 who had immediate neurologic deficit on initial postoperative evaluation, leaving 790 consecutive patients. We evaluated a wide range of demographic, preoperative physiological and intraoperative data, using univariate and multivariable statistical analyses. RESULTS: Twenty-one of 790 (2.7%) patients had delayed neurologic deficit. Significant univariate predictors included preoperative renal dysfunction (odds ratio 5.9; P <.006), acute dissection (odds ratio 3.9; P <.05), extent II thoracoabdominal aorta (odds ratio 3.0; P <.03), and use of adjuncts (cerebrospinal fluid drainage and distal aortic perfusion; odds ratio 7.7; P <.03). The use of the adjuncts dropped from the multivariable model but all other factors remained. No other significant risk factors were identified. Twelve of 21 (57%) patients recovered neurologic function with optimization of blood pressure and cerebrospinal fluid drainage. CONCLUSION: Preoperative renal dysfunction, acute dissection, and extent II thoracoabdominal aorta are significant predictors of delayed neurologic deficit. Previous studies have demonstrated that the use of adjuncts protects against immediate neurologic deficit. The findings of this study are consistent with the hypothesis that adjuncts reduce ischemic insult enough to prevent immediate neurologic deficit but that a period of increased spinal cord vulnerability persists several days postoperatively.

Distal aortic perfusion and cerebrospinal fluid drainage for thoracoabdominal and descending thoracic aortic repair: ten years of organ protection.

OBJECTIVE: To report the long-term results of our experience using cerebrospinal fluid drainage and distal aortic perfusion in descending thoracic and thoracoabdominal aortic repair. SUMMARY BACKGROUND DATA: Repair of thoracoabdominal and thoracic aortic aneurysm by the traditional clamp-and-go technique results in a massive ischemic insult to several major organ systems. Ten years ago, we began to use distal aortic perfusion and cerebrospinal fluid drainage (adjunct) to reduce end-organ ischemia. METHODS: Between January 1991 and February 2003, we performed 1004 thoracoabdominal or descending thoracic repairs. Adjunct was used in 741 (74%) of 1004. Multivariable data were analyzed by Cox regression. Number needed to treat was calculated as the reciprocal of the risk difference. RESULTS: Immediate neurologic deficit was 18 (2.4%) of 741 with adjunct and 18 (6.8%) of 263 without (P < 0.0009). In high-risk extent II aneurysms, the numbers were 11 (6.6%) of 167 with adjunct, and 11 (29%) of 38 without. Long-term survival was improved with adjunct (P < 0.002). The long-term survival results persisted after adjustment for age, extent II aneurysm, and preoperative renal function. CONCLUSION: Use of adjunct over a long period of time has produced favorable results; approximately 1 neurologic deficit saved for every 20 uses of adjunct overall. In extent II aneurysms, where the effect is greatest, this increases to 1 saved per 5 uses. Adjunct is also associated with long-term survival, which is consistent with mitigation of ischemic end-organ injury. These long-term results indicate that cerebrospinal fluid drainage and distal aortic perfusion are safe and effective adjunct for reducing morbidity and mortality following thoracic and thoracoabdominal aortic repair.