血液透析患者动静脉内瘘成功的影响因素

目的　了解影响动静脉内瘘成功的因素。方法　 40例新建内瘘病例术中测动静脉管径、动脉血流量、吻合口口径、内瘘血流量及术前平均动脉压。其中 ,18例还进行多普勒超声检查 ,测量术前动静脉管径、动脉血流量及术后连续 6周随访内瘘血流量和管径。结果　通过单因素、多因素回归分析 ,平均动脉压、动脉血流量与术后短时间的内瘘血流量呈正相关 (P <0 0 5 ) ;静脉管径与术后内瘘血流量呈正相关 (P <0 0 5 )。术后随访期内瘘血流量和管径随时间逐渐增加 (P <0 0 5 )。结论　低血压、静脉管径细会造成内瘘失败 ,术前动脉血流量达到 2 0ml/min术后可很快获得满意的血流量 ;吻合口口径在 8～ 10mm较为适宜 ;内瘘的使用尽量在 6周以后。     

血液透析患者动静脉内瘘栓塞的预防护理

目的总结血液透析患者动静脉内瘘栓塞的预防护理经验。方法对29例患者以动静脉内瘘穿刺行血液透析治疗,血液透析期间加强内瘘术后早期预防护理,规范内瘘穿刺技术,正确设置脱水量,正确处理回血和止血,观察动静脉内瘘狭窄情况并早期处理,指导患者加强内瘘日常维护。结果血液透析期间4例发生动静脉内瘘闭塞,其中3例经改用其他部位重新造瘘后应用良好,1例经溶栓处理后恢复正常;余25例内瘘正常。29例均按疗程透析,效果满意。结论预防护理可减少血液透析并发症的发生,是内瘘正常使用的保障。     

Swelling of the hand after arteriovenous fistula for hemodialysis

Despite a high patency rate and low incidence of infections, several complications have been described with the Brescia subcutaneous arteriovenous fistula. We recently observed five patients with swelling of the hand and wrist secondary to increased distal vein flow. Ligation of the distal vein, with or without proximal reconstruction resulted in cure. Proximal vein patency must be assessed.     

The role of surveillance in mature arteriovenous fistula management

The existing guidelines recommend arteriovenous fistulae (AVF) surveillance by access blood flow (Qa) measurement and the correction of hemodynamically significant stenoses to prolong access survival. Unfortunately, many studies supporting these recommendations are inadequate methodologically; therefore, both the optimal criteria for surveillance and the value of preventive stenosis repair in AVF remain controversial. Recent literature confirms that Qa measurement allows an accurate identification of both stenosis (area under the curve (AUC) ranging from 0.80-0.93) and access at risk of failure (AUC ranging from 0.82-0.98) in AVFs and suggests a Qa <700-1000 ml/min and/or a reduction in Qa >25% as optimal predictors for stenosis and a Qa <400 ml/min for incipient thrombosis. Recent prospective studies evaluated whether Qa surveillance could improve AVF patency rates compared to monitoring based on clinical and dialysis-related criteria alone. The majority of studies have historical, rather than concurrent, control groups and provide conflicting results, some showing a reduction and some showing no change in thrombosis rates by Qa monitoring. On the other hand, the few randomized controlled studies available show that Qa surveillance, when coupled with preemptive intervention, reduces the already low thrombosis rate in AVF and suggest that the functional access life can be prolonged. However, there is still the need for additional methodologically adequate studies to understand fully the role of surveillance in AVF management.     

Prosthetic arteriovenous fistula for vascular access in hemodialysis.

Vascular access through subcutaneous prosthetic arteriovenous fistulas was studied in eighteen dogs. Dacron velour and woven Dacron grafts (6 mm diameter) were constructed across the lower abdomen between the common femoral artery and the opposite common femoral vein. In heparinized animals 197 percutaneous punctures were made with a "14 guage hemodialysis cannula at weekly intervals. Over a period of one and a half years there was no instance of infection. One of the fourteen Dacron velous and all four woven Dacron fistulas thrombosed. These data suggested the feasibility of achieving repetitive blood access through Dacron velour vascular prostheses. Nineteen Dacron velour fistula bypasses between the brachial artery and median basilic vein were performed in fifteen selected patients for a total dialysis period of ninety-six months. Failed standard subcutaneous fistulas or absence of suitable vessels in the upper extremity were indications for the primary procedure. Of three looped forearm fistulas, two thrombosed at twenty-two and two months. Complications among sixteen straight bypasses in the arm included two graft infections and one cannula tract infection. There were no instances of thrombosis in this group. The advantages of single needle dialysis in these high risk patients have been emphasized. Eleven grafts are presently functioning two to nine months postoperatively. Our preliminary results suggest that a Dacron velour fistula merits consideration as an alternative for vascular access in maintenance hemodialysis.     

The role of echocardiography in prognosis for dysfunction and abandonment of radiocephalic arteriovenous fistula in elderly Chinese patients on hemodialysis

The objective of this study was to examine the impact of cardiac structure and function at baseline on the outcomes associated with arteriovenous fistula (AVF) in patients on hemodialysis (HD). Patients who initiated HD aged ≥70 years and received a mature AVF creation were included retrospectively. Echocardiographic parameters measured within 1 week before AVF creation were acquired. The observational period for each patient was from the point of AVF creation to the last time of follow-up unless AVF abandonment or death occurred. Kaplan-Meier and Cox proportional hazard regression analyses were conducted. A total of 82 elderly Chinese HD patients with mature radiocephalic AVF (RCAVF) and EF ≥50% were analyzed. During the median study period of 26.8 (12-40) months, 42 (51.2%) experienced RCAVF dysfunction and 34 (41.5%) progressed to abandonment. Primary and cumulative patencies at 6, 12, 24, and 36 months were 81%, 73%, 48%, 38%, and 84%, 81%, 68%, 55%, respectively. Left ventricle end-diastolic volume (LVEDV) ≤103.5 mL (HR = 2.5, P = .019) and the right side of RCAVF (HR = 3.59, P = .003) significantly predicted RCAVF dysfunction. The main pulmonary artery internal diameter (MPAID) ≤21.5 mm (HR = 4.3, P = .001) as well as the right side (HR = 2.95, P = .047) were the independent predictors for RCAVF abandonment. In conclusion , LVEDV, MPAID assessed by echocardiography and the right side of RCAVF, showed significant predictive implications for the outcomes of RCAVF. Disparities among nationalities in the areas of utilization and patency of AVFs necessitate additional studies.     

The role of short daily hemodialysis in the control of hyperphosphatemia, secondary hyperparathyroidism and anemia

Background

Hyperphosphatemia, secondary hyperparathyroidism (SHPT) and anemia are common secondary complications in hemodialysis patients with end-stage renal disease (ESRD). Compared with conventional hemodialysis (CHD), short daily hemodialysis (sDHD) has been found to be more effective in patients with ESRD. The objective of this study was to determine whether sDHD could improve hyperphosphatemia, SHPT and anemia in patients with ESRD.

Methods

Twenty-seven patients (11 women and 16 men, 46.8 ± 13.4 years old) were switched from CHD to sDHD. All hematologic parameters were measured prior to the switch (baseline), at 3 months after the switch (sDHD₁) and at 6 months after the switch (sDHD₂).

Results

The serum phosphate decreased from 2.54 ± 0.32 mmol/L at baseline to 2.15 ± 0.36 mmol/L (p < 0.001) at sDHD₁ and 1.97 ± 0.33 mmol/L (p < 0.001) at sDHD₂. Calcium-phosphate product decreased from 5.18 ± 1.24 mmol²/L² at baseline to 4.20 ± 0.71 mmol²/L² (p < 0.001) at sDHD₁ and 4.02 ± 0.83 mmol²/L² (p < 0.001) at sDHD₂. The serum PTH levels decreased from 223.9 ± 124.7 pmol/L at baseline to 196.3 ± 101.3 pmol/L (p < 0.05) at sDHD₂. The hemoglobin concentration increased significantly from CHD to sDHD. However, the requirement for erythropoietin (EPO) dose decreased from 6847.8 ± 1057.3 u/week at baseline to 5869.6 ± 1094.6 u/week (p < 0.05) at sDHD2.

Conclusions

sDHD may decrease serum phosphate, calcium-phosphate product and PTH, increase hemoglobin levels and decrease exogenous EPO dose requirements compared with CHD in hemodialysis patients.     

CT血管重建评估血液透析患者动静脉内瘘

动静脉内瘘形态改变是影响透析的首要原因,及早发现能改善血液透析,同时延长内瘘使用寿命.我们采用CT血管重建评估动静脉内瘘形态,取得较好的效果.     

经桡动脉行自体动静脉内瘘功能不良的介入治疗

目的探讨经桡动脉行自体动静脉瘘(AVF)腔内成形和(或)溶栓治疗的可行性。方法于因AVF狭窄或血栓闭塞而需行介入治疗的患者中,选取经桡动脉入路介入治疗的8例患者进行回顾性分析。结果首次造影证实6例患者为AVF重度狭窄,即刻行腔内球囊成形术,术后狭窄程度改善;对2例急性血栓形成患者行动脉内溶栓治疗,次日复查造影示血栓溶解,其中1例溶栓后造影显示吻合口附近静脉狭窄严重,行PTA治疗,另1例狭窄程度较轻者未进一步PTA治疗。对8例患者随访2~13个月,其中7例可正常行AVF透析,1例单纯PTA治疗患者2个月后再次行PTA治疗,4个月后因AVF功能不良而改行颈内静脉插管透析。结论经桡动脉行AVF功能不良的介入治疗有一定的可行性。     

Timing of first arteriovenous fistula cannulation in children on hemodialysis

Background

Due to lower complication rates in comparison to central venous catheter (CVC) arteriovenous fistulas (AVFs) are now the preferred hemodialysis access. Recommendations for the first access cannulation range from 6 to 12 weeks, which could lead to temporary or even permanent preference for CVC while awaiting the maturation of the newly created AVF. The aim of this study was to evaluate the influence of first cannulation of AVFs on primary (PP) and secondary (SP) patency rates in children on hemodialysis (HD).

Methods

This was a retrospective cohort study of 42 pediatric patients with a median age of 14 (range 7–17) years. At the time of surgical AVF creation 21 patients (end-stage renal disease) were still on HD via CVC or peritoneal catheter, while 21 were pre-emptive with initiation of HD expected within a few weeks. All patients received an AVF by the same experienced surgeon between February 1993 and May 2014. Primary failure (PF) was defined as the inability to use the AVF even once due to absent maturation or occlusion within 4 weeks after creation. PP was defined as the interval from time of access placement to any intervention designed to maintain or reestablish patency, to access thrombosis or the time of measurement of patency, while SP was defined as the total lifespan from creation to access abandonment, end of follow-up or loss.

Results

Primary failure was observed in six (14.3 %) of 42 AVFs (all radiocephalic fistulas) within the first 10 days after cannulation. Excluding PF, the PP/SP rates at 1, 3, 6, 12, 18 and 24 months were 100/100, 91/99, 86/98, 76/95, 55/85 and 44/77 %, respectively. There was a significant decrease in PP when first cannulation was performed within the first 30 days after creation compared to first cannulation performed after 30 days (p?=?0.004). In terms of PP/SP outcome and timing of the first cannulation, there was no significant difference in thee outcome of PP/SP between first cannulation within the first 45 days after creation and that after 45 days (p?=?0.091/0.883).

Conclusions

The findings suggest that cannulation of AVF within 30 days after surgical creation reduces PP, while SP may be influenced less by time until cannulation. We also found no significant differences in PP after maturing periods of >45 days.

     

Conversion of tunneled hemodialysis catheter-consigned patients to arteriovenous fistula

OBJECTIVE: Despite their high incidence of complications, costs, morbidity, and mortality, nearly 27% of the chronic hemodialysis (HD) patients are receiving treatment via a tunneled hemodialysis catheter (TDC). METHODS: In this prospective analysis, an interventional nephrology team employed an organized program consisting of vascular access (VA) education and vascular mapping (VM) to TDC-consigned patients. A full range of surgical approaches for arteriovenous fistula (AVF) creation, including vein transpositions, was exercised. Physical examination was performed every 1 to 2 weeks after surgery to assess the development of the AVF. Fistulas that failed to develop adequately to support HD (early failure) underwent salvage [percutaneous transluminal angioplasty (PTA), accessory vein obliteration (AVL)] procedures. RESULTS: One hundred twenty-one TDC-consigned patients received VA education. Eighty-six (71%) agreed to undergo VM. Two groups were identified. Group I (N= 66; using TDC for 7.2 +/- 1.8 SD months) had never had an arteriovenous access; group II (N= 20; using TDC for 12.3 +/- 4.0 months) had a history of one or more previously failed arteriovenous accesses. Upon VM, 64/66 (97%) in group I and 18/20 (90%) in group II were found to have adequate veins for AVF creation. Seven patients (11%) in group I and 3 (17%) in group II refused surgery. In group I, 57 (89%) received an arteriovenous access (radiocephalic AVF = 15, brachiocephalic AVF = 35, transposed brachiobasilic AVF = 3, brachiobasilic AVG = 4). In group II, 15 (83%) received a transposed AVF (radiobasilic = 2, brachiobasilic = 13). Sixteen fistulas (30%) in group I and 8 (53%) in group II had early failure. All except for one fistula in each group were salvaged using PTA and/or AVL. All 70 accesses (AVF = 66, AVG = 4) remain functional, with a mean follow-up of 8.5 +/- 3.6 months. CONCLUSION: These results demonstrate that an organized approach based upon a comprehensive program utilizing VA counseling, VM, application of full range of surgical techniques, and salvage procedures can be very successful in providing optimum vascular access to the catheter-dependent patient.     

Nerve conduction changes following arteriovenous fistula construction in hemodialysis patients

Background  

Peripheral neuropathy is a common complication of chronic renal failure (CRF). Superimposed neuropathies may complicate arteriovenous fistulas (AVF) construction. The aim of this study was to evaluate the effect of AVF construction on nerve conduction.