Swan-neck versus straight peritoneal dialysis catheter: Long-term effect on patient and method survival.

Peritoneal dialysis (PD) is limited mainly by a higher technique failure rate as compared to hemodialysis (HD), catheter malfunction being an important reason. Intra- and extra-peritoneal catheter configuration may be associated with mechanical and infectious complications affecting method survival. We report our experience with two extra-peritoneal catheter configurations: the straight and the swan-neck (SN) catheters. A total of 85 consecutive patients, 58 males and 27 females were included in the study. Among them, 26 were diabetics; 52 were treated with automated PD (APD) and 33 with continuous ambulatory PD (CAPD). Straight catheters were used in 38 patients (straight group) and SN catheters in 47 patients (SN group). Straight catheters were mostly used in the first 6-year period while SN catheters in the last 6-year period. The baseline demographics were similar between the two groups. A significantly higher frequency of APD use was observed in SN group. Technique survival was better with SN versus straight (log-rank test, P = 0.01) while patient and catheter survival were similar. A better technique survival is noted in our group of patients with SN catheters. An additional factor could be the significantly higher frequency of APD use in this group. Changes in PD solutions' composition could also contribute to improvement in technique survival. The outcome for patients and catheter types used was similar.

Vitamin E-coated cellulose acetate dialysis membrane: long-term effect on inflammation and oxidative stress.

BACKGROUND: Chronic inflammation and oxidative stress are prevalent in hemodialysis (HD) patients. We evaluated the long-term effect of a vitamin E-coated cellulose acetate (CAE) membrane on oxidative stress and inflammation. METHODS: Nine patients were switched to CAE membrane for 3 months and then changed back to polysulfone (PS) membrane again for 6 months. Reactive oxygen metabolites and derivatives (d-ROMs), total antioxidant capacity (TAC) and superoxide dismutase (SOD) (oxidative stress biomarkers), high-sensitivity C-reactive protein (Hs-CRP), and interleukin-6 (IL-6) (inflammation biomarkers) were measured. RESULTS: d-ROMs decreased and TAC rose significantly at the end of the study, whereas SOD increased rapidly and immediately after the end of CAE treatment. Hs-CRP and IL-6 levels were significantly lowered at the end of the study. CONCLUSIONS: Vitamin E supplementation by vitamin E-coated CAE dialysis membrane suppresses oxidative stress and inflammation.

Hemoglobin normalization results in lower dialysis dose, despite high dialysate flow. Single needle offers inadequate dialysis.

Anemia correction by erythropoietin favorably affects dialysis outcome but may also reduce dialysis efficiency increasing morbidity and mortality. Single needle dialysis (SN) and high dialysate flow (DF) are dialysis variations. We studied the effect of hemoglobin (Hb) normalization on dialysis adequacy under high DF. We also compared double needle (DN) and SN dialysis efficiency. Seventeen stable anuric patients (13 M, 4 F), aged 62 (40-90), on hemodialysis for 48 months (8-204), were studied in two, 6 months apart, periods of low (A) and high Hb (B), during a midweek 4 h dialysis with DN and SN. DF was 500 in A and 800 ml/min in B. Rebound urea samples, 20 min post dialysis, were used for computer calculated double pool urea kinetics. Hb levels were 128 +/- 8 g/L (B) vs. 119 +/- 14 g/L (A), P < 0.03. Despite the use of higher DF less dialysis was delivered in B vs. A, under DN or SN (DN: URR 64.8 +/- 5.8 vs. 69.7 +/- 5.2%, Kt/Vequil. 1.09 +/- 0.19 vs. 1.26 +/- 0.21, nPCR 1.37 +/- 0.29 vs. 1.60 +/- 0.36g/kg/day, changes <0.001, SN: URR 49.7 +/- 7.5% vs. 52.6 +/- 8.8%, Kt/Vequil. 0.74 +/- 0.16 vs. 0.82 +/- 0.23, nPCR 1.05 +/- 0.33 vs. 1.20 +/- 0.31, changes NS). SN was found significantly (P < 0.001) less efficient than DN in A and B. Serum creatinine drop was significantly (P < 0.001) less in both periods with SN vs. DN. Hb (SN in B) correlated inversely to Kt/V (r = -0.5705, P < 0.02) and URR (r = -0.6432, P = 0.005). Hb correction to normality is associated with a decrease in dialysis efficiency. The use of high dialysate flow does not compensate for this loss. SN delivers inadequate dialysis independently of dialysate flow or hemoglobin concentration.

Long-term control of hypertension in dialysis patients by low dose atenolol.

Hypertension in dialysis patients is considered a major factor in cardiovascular mortality. We investigated long-term efficacy of intermittent atenolol (AT) administration in 10 (7M/3F) hypertensive dialysis patients, age 60.5 (38-72), on dialysis for 56.5 months (8-156) thrice per week (10.5-13.5 h/w) (A). A similar group of 11 normotensive patients served as controls (B). Hypertension was defined as BP> 140/90 (day) and >120/80 mmHg (night) by a 44-h ambulatory BP monitoring (ABPM) after the mid-week session. Dialysis ultrafiltration, hematology, biochemistry were similar in A and B. Atenolol was started on an alternate day, 37.5 mg/w and increased as needed. After 34 days (6-80) and a dose of 68.75 (37.5-450) mg/w, BP dropped (ABPM: MAP 104+/-11.5 to 95.6+/-10.4 mmHg, P=0.0025) similar to controls and daytime HR dropped: 84.6+/-9.2 to 69.3+/-8.2, P=0.0008 and at night: 79.5+/-7.6 to 68.6+/-8.6 b/1' becoming lower than in B: 83+/-10.8/69.3+/-8.2, P=0.009 and 80.5+/-11.7/68.6+/-8.6 b/1' (P=0. 02). Six months later ABPM in A as well as echocardiography in A and B remained unchanged. Moderate, volume independent hypertension in stable dialysis patients is easily controlled during the interdialytic period by small intermittent atenolol doses.