Shinichiro Tsuchiya

Modified MILLER banding procedure for managing high-flow access and dialysis-associated steal syndrome

Purpose Both high-flow vascular access (VA) and dialysis-associated steal syndrome are serious complications requiring a flow reduction technique. We adopted the minimally invasive limited ligation endoluminal-assisted revision (MILLER) banding procedure with some modifications to control the high blood flow and steal syndrome during VA procedures and retrospectively assessed the outcome. Methods Seven patients with high-flow access (access flow >1400 ml/min) and five patients with steal syndrome (with pain, coldness, or cyanosis) were treated using the MILLER banding method. Flow volume of the brachial artery was monitored using Doppler ultrasonography during the banding procedure. In patients with steal syndrome, the finger probe of a pulse oximeter was attached to a finger on the ipsilateral side, and the peripheral oxygen saturation (SpO2) was monitored. Results In the high-flow group, the mean access blood flow (Qa) decreased from 2043 ± 463 ml/min (mean ± SD) to 1248 ± 388 ml/min (p<0.001). In the steal syndrome group, the SpO2 value improved in all steal syndrome patients after banding. Symptoms were almost relieved in two steal syndrome patients. The Qa in the steal group decreased from 997 ± 867 to 548 ± 376 ml/min (p = 0.12). The secondary patency rates of the high-flow and steal groups at 6 months were 83.3% and 50%, respectively. Conclusions The MILLER banding procedure with intraoperative access flow monitoring is effective to treat high-flow VA and steal syndrome.

Experience with the Jms Fully Automated Dialysis Machine

A fully automated dialysis machine has been developed and evaluated clinically. It uses highly pure dialysate (produced by a new dialysate cleaning system) instead of the conventional physiologic saline for the processes of priming, guiding blood to the dialysis machine, replenishing fluid, and returning the blood to the body.The piping for the dialysate is in the shape of a loop, and the dialyzer coupler has no mechanical parts that might become contaminated. As a result of these and certain other improvements in machine design, it is now possible to obtain reasonably clean dialysate. For the priming process, the machine uses a volume of up to 4 L of the dialysate after reverse filtration from the dialyzer. Most foreign matter or eluates can be removed from the dialyzer and the blood channels. Before blood is guided out of the body into the dialysis system, the needles inserted in the artery and vein are simultaneously connected to the blood channel, and the dialysate remaining in the channel is removed from the dialyzer. If the patient’s blood pressure falls during dialysis, the dialysate can be replenished at any desired flow rate for reverse filtration. Blood return can be started automatically when the planned dialysis time has elapsed and the target water volume has been removed. The cleaned dialysate is infused from the dialyzer into the blood channel by reverse filtration to allow the blood to be returned to the body via both the artery and the vein at the same time.A total of 216 units of this fully automated dialysis machine have been placed in service at two of our facilities. During the 6 month period beginning in July 2001, they were used for 40,000 hemodialysis sessions in 516 patients. During the dialysate preparation process, the endotoxin levels in the reverse osmosis (RO) water, prefilter dialysate, and reverse filtered dialysate were all less than 1 EU/L. The time required to guide blood into the dialyzer (n = 39) decreased from the 4.6 ± 1.4 minutes with the conventional machines to 3.2 ± 0.6 minutes with the new machine (p < 0.01). The time required to return blood to the body also decreased from 8.6 ± 2.2 minutes with the conventional machines to 6.8 ± 0.7 minutes with the new machine (n = 34).No mechanical trouble was encountered with the fully automated dialysis machine units during the 40,000 hemodialysis sessions, and the workload of the dialysis unit staff in terms of the time needed to guide out and return blood to the body was significantly reduced. Because the machine simplifies the maneuvers required during hemodialysis, it is expected to contribute greatly to preventing medical accidents and in hospital infections associated with hemodialysis.

Distal ulnar-basilic fistula as the first hemodialysis access

Purpose A distal forearm ulnar-basilic (UB) arteriovenous fistula (AVF) can be chosen if a radial-cephalic (RC)-AVF is not suitable for a primary AVF. However, limited data are available on the feasibility of using a distal forearm UB-AVF as an option for primary AVF. Methods This retrospective analysis included 446 patients for whom AVFs (417 RC and 29 UB) had been newly created from January 2003 to December 2009, at our hospital. Patients in whom the arterial or venous anatomy precluded RC-AVF creation, UB-AVF was established as distally as possible on the forearm. Patency, defined as access survival after creation, was calculated using Kaplan-Meier analysis. The difference in patency between the two groups was examined using log-rank test. Results The primary patency of UB-AVFs was significantly lower than that of RC-AVFs (p=0.037, log-rank test). The primary patency rate at 1 year was 25.0% versus 44.7%, respectively. However, there was no significant difference in secondary patency between the two groups. The secondary patency rate at 1 year was 85.5% for UB-AVFs versus 82.9% for RC-AVFs. The incidence rate of percutaneous angioplasty until access abandonment per patient-years was 1.100 for UB-AVFs versus 0.671 for RC-AVFs. There was no difference in the time to maturation between the two groups. Conclusions The secondary patency rate of UB-AVF is similar to that of RC-AVF. We recommend the creation of an UB-AVF when an RC-AVF is not a suitable option for the primary AVF.

Efficacy of Intra‐Arterial Treatment for Massive Gastrointestinal Bleeding in Hemodialysis Patients

The incidence of acute nonvariceal massive gastrointestinal bleeding (GIB) is higher in hemodialysis (HD) patients than in healthy individuals, and this is often a life‐threatening event. We evaluated the efficacy of intra‐arterial treatment for GIB in HD patients. Between January 2006 and June 2012, eight HD patients with GIB were treated with superselective transarterial embolization. Of the eight cases, one was duodenal bleeding, two were jejunal bleeding, one was ileocecum bleeding, two were ascending colonic bleeding, and two were sigmoid colonic bleeding. After examining the site of bleeding by endoscopy or contrast‐enhanced computed tomography (CT), embolizations with microcoils, gelatin sponges, or N‐butyl cyanoacrylate were performed through interventional radiology (IVR). In all cases, blood transfusions were frequently administered. Six of the eight patients with GIB were successfully salvaged by transarterial embolization. In one case, duodenal bleeding was refractory to endoscopic treatment. Embolization was performed twice in this case; however, the patient died of an aneurysm rupture at the embolization site 24 days after the embolizations. In another case, massive jejunal bleeding and disseminated intravascular coagulation were identified at the time of the first examination, and the patient died of multiorgan failure 26 days after the embolization. On the basis of our experience, we established an effective treatment strategy for HD patients with acute nonvariceal massive GIB, by immediately identifying the exact site and degree of bleeding using contrast‐enhanced computed tomography and performing early treatment with transarterial embolization.

De Novo Renal Cell Carcinoma in a Kidney Allograft 20 Years after Transplant

Renal cell carcinoma (RCC) in a kidney allograft is rare. We report the successful diagnosis and treatment of a de novo RCC in a nonfunctioning kidney transplant 20 years after engraftment. A 54-year-old man received a kidney transplant from his mother when he was 34 years old. After 10 years, chronic rejection resulted in graft failure, and the patient became hemodialysis-dependent. Intravenous contrast-enhanced computed tomography (CT) for the evaluation of gastrointestinal symptoms revealed a solid 13 mm tumor in the kidney graft. The tumor was confirmed on ultrasound examination. This tumor had not been detected on a surveillance noncontrast CT scan. Needle biopsy showed that the tumor was an RCC. Allograft nephrectomy was performed. Pathological examination showed that the tumor was a Fuhrman Grade 2 RCC. XY-fluorescence hybridization analysis of the RCC showed that the tumor cells were of donor origin. One year after the surgery, the patient is alive and has no evidence of tumor recurrence. Regardless of whether a kidney transplant is functioning, it should periodically be imaged for RCC throughout the recipients lifetime. In our experience, ultrasonography or CT with intravenous contrast is better than CT without contrast for the detection of tumor in a nonfunctioning kidney transplant.

Umbilical Hernia in Peritoneal Dialysis Patients: Surgical Treatment and Risk Factors

No previous reports have focused on surgical treatments and risk factors of umbilical hernia alone in peritoneal dialysis (PD) patients. Herein, we evaluated the treatments and risk factors. A total of 411 PD patients were enrolled. Of the 15 patients with umbilical hernia (3.6%), six underwent hernioplasty. There was no recurrence in five patients treated with tension‐free hernioplasty. The mean PD vintage after onset of hernia in the hernioplasty group tended to be longer than that in the non‐hernioplasty group. An incarcerated hernia occurred in one non‐hernioplasty patient. Although the incidence was significantly higher among women (P = 0.02), female sex was not a risk factor for umbilical hernia (P = 0.08). Our findings suggest that umbilical hernias should be repaired for continuing PD. Furthermore, there were no significant risk factors for umbilical hernia in PD patients. Future studies with larger sample groups are required to elucidate these risk factors.

Percutaneous transluminal angioplasty for central venous disease in dialysis patients: influence on cardiac function.

Purpose Increased vascular access flow after percutaneous transluminal angioplasty (PTA) for central venous stenosis and occlusion (central venous disease, CVD) can affect cardiac function in hemodialysis (HD) patients. We evaluated the cardiac function, etiology, and treatment in HD patients with CVD. Methods HD patients with CVD treated by PTA between June 2006 and February 2013 were studied. Results Of the 26 patients, 22 had left arteriovenous fistulas (AVFs), 1 left arteriovenous graft (AVG), 2 right AVFs, and 1 right AVG. CVD sites were the left brachiocephalic vein (LBCV; n=13), left subclavian vein (LSCV; n=7), both LBCV and LSCV (n=3), right BCV (n=2), and right SCV (n=1). Computed tomography findings indicated a high extrinsic compression rate for the LBCV (91%) and LSCV (50%). The success rate of PTA was 96%. The primary patency rates at 3, 6, 9, and 12 months were 81%, 73%, 65%, and 57%, respectively. The post-PTA brachial artery flow volume was significantly increased compared with the pre-PTA volume (1306 vs. 957 ml/min; p=0.005). The post-PTA left ventricular ejection fraction and expiration inferior vena cava diameter were the same as the pre-PTA values (57% versus 60%, p=0.2 and 17 versus 17 mm, p=0.9, respectively). Conclusions Our findings suggest that increased vascular access flow after PTA for CVD has no relation to cardiac function.

Usefulness of the Japanese version of the 5-D itch scale for rating pruritus experienced by patients undergoing hemodialysis

BackgroundPruritus in patients undergoing hemodialysis reduces quality of life via insomnia and depression, and negatively affects prognosis. For diagnosing pruritus, selecting therapeutic strategies, and determining therapeutic outcomes, methods are needed for objectively quantifying the degree of itchiness. In 2015, the Japanese version of the 5-D itch scale (5D-J), originally developed in the USA in 2010, was developed as a simple self-administered questionnaire; it evaluated the degree of itchiness based on five components: (1) duration of itchiness, (2) degree of itchiness, (3) direction of itchiness, (4) disability caused by itchiness, and (5) distribution of itchiness. 5D-J is useful for comprehensively assessing multiple elements related to itchiness. We used 5D-J to assess the degree of itchiness experienced by patients undergoing hemodialysis to investigate its clinical usefulness.MethodsSubjects were 336 patients undergoing maintenance hemodialysis at our facility in October 2016; they were selected from 383 patients, of whom 20 were excluded because their itchiness had a dermatologic origin and 27 were excluded because their localized itchiness was related to vascular access, respectively. The status of itchiness (duration, degree, direction, disability, and distribution) of the patients was surveyed in October 2016 using 5D-J; total scores were calculated and used for assessing the itchiness experienced by patients. We additionally investigated whether 5D-J scores correlated with visual analog scale (VAS) and Shiratori severity scores for pruritus.ResultsDegree was reported as “not present” by 124 patients (36.9%), “mild” by 164 (48.8%), “moderate” by 46 (13.7%), “severe” by 2 (0.6%), and “unbearable” by 0 (0%). Total score was 5 points in 55 patients (16.4%), 6–9 in 176 (52.4%), 10–14 in 95 (28.3%), 15–19 in 9 (2.7%), 20–24 in 1 (0.3%), and 25 in 0 (0%). The 5D-J total and VAS scores were strongly correlated (r = 0.7159; p < 0.001). The 5D-J total score correlated with “daytime itchiness” (r = 0.6441; p < 0.001) and “nighttime itchiness” (r = 0.6352; p < 0.001) on the Shiratori severity score.Conclusions5D-J may be useful for objectively assessing itchiness experienced by patients undergoing hemodialysis.

Current Status and Treatment Strategies of Hemodialysis-Associated Pruritus

BACKGROUND Hemodialysis-associated pruritus (HAP) is often treatment-resistant, and is a serious comorbidity that adversely affects prognosis and reduces patient quality of life through sleep disruption and depression. SUMMARY HAP can arise from a combination of several causes; accordingly, it is often resistant to treatment. HAP patients need the specific causes of their itching to be identified, with a comprehensive approach to treatment. We have implemented our own therapeutic algorithm, which covers cause specification, for HAP since June 2009. This resulted in a significantly decreased proportion of patients with itching (2016 vs. 2009: 77.3 vs. 96.6%), accompanied by a significant decrease in median visual analogue scale itching score (2016 vs. 2009: 21.0 vs. 53.0 mm), for patients treated for itching at our facility in October 2016. Key Messages: HAP patients need the causes of their itching to be specified, and to be treated with a comprehensive approach. Alleviation of itching is anticipated to improve patient quality of life and prognosis.

The efficacy of drug-eluting stent for recurrent central venous restenosis in a patient undergoing hemodialysis:

Introduction: Recurrent central venous restenosis is problematic in patients with ipsilateral arteriovenous fistula. We report our experience using a drug-eluting stent for the treatment of recurrent central vein restenosis. Case report: A 60-year-old man consulted our hospital because of recurrent swelling of his left upper limb with radial-cephalic arteriovenous fistula that originated in the distal forearm. More than 3 years prior, two bare-metal stents were placed for the obstructed lesions in the left subclavian and brachiocephalic venous lesions, and repeated balloon angioplasty for recurrent in-stent stenosis was performed approximately every 3 months. Angiography with iodinated contrast agents revealed an approximately 3-cm-long restenosis at the distal part of the bare-metal stents. One drug-eluting stent (Zilver PTX Drug-Eluting Peripheral Stent; Cook Medical, Bloomington, IN, USA) was deployed at the narrowing lesion, followed by balloon angioplasty. The stenotic lesion was successfully and safely dilated. The patient consulted our hospital 5.5 months after drug-eluting stent placement because of restenosis at the distal part of the drug-eluting stent, but only in a shorter segment than before. Freedom from clinically driven target-lesion revascularization (TLR) extended from 3.1 to 5.5 months after drug-eluting stent placement. Although additional implantation of the second drug-eluting stent was required 14.6 months after the first drug-eluting stent placement, freedom from TLR before/after the second drug-eluting stent placement extended from 4.4 months to more than 8.6 months. Conclusion: Drug-eluting stent placement is an effective strategy for recurrent central venous stenosis in patients with ipsilateral arteriovenous fistula. To our knowledge, this is the first report of drug-eluting stent placement for recurrent venous stenosis in a patient undergoing hemodialysis.