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Extended-release dipyridamole plus low-dose aspirin (ERDP/ASA) prolongs primary unassisted graft patency of newly created hemodialysis arteriovenous grafts, but the individual contributions of each component are unknown. Here, we analyzed whether use of aspirin at baseline associated with primary unassisted graft patency among participants in a randomized trial that compared ERDP/ASA and placebo in newly created grafts. We used Cox proportional hazards regression, adjusting for prespecified baseline comorbidities and covariates. Of all participants, 43% reported use of aspirin at baseline; of these, 82% remained on nonstudy aspirin (i.e., excluding ERDP/ASA) at 1 year. After 1 year of follow-up, the incidence of primary unassisted patency among participants using aspirin at baseline was 30% (95% CI: 24 to 35%) and among those not using aspirin was 23% (95% CI: 18 to 27%). Use of aspirin at baseline associated with a dose-dependent prolongation of primary unassisted graft patency that approached statistical significance (adjusted HR, 0.83; 95% CI: 0.68 to 1.01; P = 0.06). Use of aspirin at baseline did not associate with prolongation of cumulative graft patency or participant survival. In conclusion, use of aspirin associates with a trend toward longer primary unassisted patency of newly placed hemodialysis grafts similar to that observed for ERDP/ASA.

Arteriovenous graft stenosis leading to thrombosis is a major cause of complications in patients undergoing hemodialysis. Procedural interventions may restore patency but are costly. Although there is no proven pharmacologic therapy, dipyridamole may be promising because of its known vascular antiproliferative activity.We conducted a randomized, double-blind, placebo-controlled trial of extended-release dipyridamole, at a dose of 200 mg, and aspirin, at a dose of 25 mg, given twice daily after the placement of a new arteriovenous graft until the primary outcome, loss of primary unassisted patency (i.e., patency without thrombosis or requirement for intervention), was reached. Secondary outcomes were cumulative graft failure and death. Primary and secondary outcomes were analyzed with the use of a Cox proportional-hazards regression with adjustment for prespecified covariates.At 13 centers in the United States, 649 patients were randomly assigned to receive dipyridamole plus aspirin (321 patients) or placebo (328 patients) over a period of 4.5 years, with 6 additional months of follow-up. The incidence of primary unassisted patency at 1 year was 23% (95% confidence interval [CI], 18 to 28) in the placebo group and 28% (95% CI, 23 to 34) in the dipyridamole-aspirin group, an absolute difference of 5 percentage points. Treatment with dipyridamole plus aspirin significantly prolonged the duration of primary unassisted patency (hazard ratio, 0.82; 95% CI, 0.68 to 0.98; P=0.03) and inhibited stenosis. The incidences of cumulative graft failure, death, the composite of graft failure or death, and serious adverse events (including bleeding) did not differ significantly between study groups.Treatment with dipyridamole plus aspirin had a significant but modest effect in reducing the risk of stenosis and improving the duration of primary unassisted patency of newly created grafts. (ClinicalTrials.gov number, NCT00067119.)

The arteriovenous graft (AVG) is most often used in hemodialysis patients when an autogenous fistula is not feasible. The optimal location (forearm or upper arm) and configuration (loop or straight) of AVGs are not known. To evaluate relationships of AVG location and configuration with patency, we conducted a secondary analysis using data from a randomized, placebo-controlled trial of dipyridamole plus aspirin for newly placed AVG.Participants of the Dialysis Access Consortium (DAC) Graft Study with newly placed upper extremity prosthetic grafts involving the brachial artery were studied. Multivariable analyses adjusting for trial treatment group, center, gender, race, body mass index, diabetes, current treatment with chronic dialysis, and prior arteriovenous vascular access or central venous catheter were performed to compare outcomes of forearm (fAVG) and upper arm (uAVG) grafts, including loss of primary unassisted patency (LPUP) and cumulative primary graft failure (CGF). Subgroup analyses of graft configuration and outflow vein used were also conducted.A total of 508 of the 649 participants (78%) enrolled in the trial had an upper extremity brachial artery graft placed, 255 with fAVG and 253 with uAVG. Participants with fAVG were less often male (33% vs 43%; P = .03), African American (62% vs 78%; P .001), and receiving dialysis at the time of surgery (62% vs 80%; P .001). Participants with fAVG had a higher mean body mass index (33 vs 29; P .001). The LPUP (fAVG 70% vs uAVG 78%; P = .07) and CGF (33% vs 36%; P = .91) were similar between fAVG and uAVG at 1-year follow-up. In multivariable analysis, AVG location (uAVG vs fAVG) was not associated with LPUP (hazard ratio, 1.21; 95% confidence interval, 0.90-1.63; P = .20) or CGF (hazard ratio, 1.36; 95% confidence interval, 0.94-1.97; P = .10). LPUP did not differ significantly between fAVG and uAVG among subgroups based on AVG configuration (P = 1.00) or outflow vein used (P = .16).Patency was comparable between fAVG and uAVG despite the larger caliber veins often encountered in the upper arm in carefully selected patients. Our findings support the traditional view that, in order to preserve a maximal number of access sites, the forearm location should be considered first before resorting to an upper arm graft.

Objective : Determine the prevalence of malnutrition per facility standards; examine interventions used to treat malnutrition; and share experiences, concerns, and solutions to problems in the management of malnutrition in dialysis patients in Texas. Design : Structured survey questionnaires. Setting : 196 outpatient hemodialysis (HD) and 86 peritoneal dialysis (PD) programs in End-Stage Renal Disease (ESRD) Network of Texas, Inc. Participants : Renal dietitians who worked in Texas dialysis facilities that treated chronic, outpatient adult, and pediatric ESRD patients on HD or PD. Measures : Criteria used to identify malnourished patients, prevalence of malnutrition in dialysis recipients, prevalence and types of interventions used to manage malnourished patients, and participation in quality management activities among renal dietitians. Results : For facilities that treated both HD and PD patients in 1996: (1) a significantly greater proportion of PD patients were identified as malnourished than HD patients: (2) facilities that had a high percentage of malnourished HD patients also had a high percentage of malnourished PD patients; (3) a significantly greater proportion of PD patients received commercial nutrition supplements than HD patients; and (4) use of tube feedings, intradialytic parenteral nutrition, intraperitoneal parenteral nutrition, and total parenteral nutrition among HD and PD patients decreased significantly from the past to the current survey year. Renal dietitians shared their experiences, concerns and solutions to problems in the management of malnutrition in this population. Conclusion : Results indicate a need to improve the nutritional status of malnourished dialysis patients, to increase consideration of tube feedings as viable nutrient delivery routes, and to maximize involvement of renal dietitians in the quality management process. With the cooperative effort of staff, care givers, patients, and family, early identification and appropriate interventions may improve the nutritional status and quality of life of dialysis patients.

Clinical observations suggest that overt rhabdomyolysis may occur if severe hypophosphatemia is superimposed upon a pre-existing subclinical myopathy. To examine this possibility, a subclinical muscle cell injury was induced in 23 dogs by feeding them a phosphorus- and calorie-deficient diet until they lost 30% of their original weight. To induce acute, severe hypophosphatemia in the animals after partial starvation, 17 of the dogs were given large quantities of the same phosphorus-deficient diet in conjunction with an oral carbohydrate supplement, which together provided 140 kcal/kg per day. After phosphorus and caloric deprivation, serum phosphorus and creatine phosphokinase (CPK) activity were normal. Total muscle phosphorus content fell from 28.0+/-1.3 to 26.1+/-2.5 mmol/dg fat-free dry solids. Sodium, chloride, and water contents rose. These changes resembled those observed in patients with subclinical alcoholic myopathy. When studied after 3 days of hyperalimentation, the animals not receiving phosphorus showed weakness, tremulousness, and in some cases, seizures. Serum phosphorus fell, the average lowest value was 0.8 mg/dl (P

Peritoneal dialysis is of established value in the management of many patients with either acute or chronic renal failure [1]. Peritonitis complicating peritoneal dialysis represents a significant clinical problem [2, 3]. When peritoneal dialysis is performed in highly specialized nursing units, the incidence of peritonitis is low. In 1973 it became apparent that the incidence of peritonitis in patients receiving peritoneal dialysis on our general medicine wards was high. A retrospective study of 116 consecutive peritoneal dialyses in these patients revealed an incidence of 20.7% of clinical peritonitis with a positive peritoneal fluid culture. It was this alarming rate of peritonitis that prompted a search for a bacteriologic filter that could be incorporated into the dialysate tubing so as to lessen the frequency of peritonitis in our general hospital population.

Untreated patients with uremia show an abnormally low resting transmembrane potential (Em) of skeletal muscle cells. This finding corresponds to impaired sodium transport. Adequate hemodialysis corrects this abnormality. Toxins derived from protein precursors have been implicated as the hypothetical cause of impaired transport and membrane depolarization in untreated uremia. To inferentially examine this hypothesis in further detail, we deliberately reduced dialysis time until Em fell in six uremic patients in whom it had been previously corrected. When Em fell, we examined the effect of reducing crude protein in their diet in conjunction with adding an essential amino acid supplement. Five of six patients who complied with the diet showed correction of their abnormally low Em despite continued reduction of dialysis time. These findings support the notion that in patients with uremia, a product of crude dietary protein may be responsible for membrane depolarization and, in addition, direct measurement of resting muscle transmembrane potential may be a useful index to determine adequacy of dialysis therapy.