Tissue ischemia worsens during hemodialysis in end-stage renal disease patients.

BACKGROUND: Cognitive deficit is a common problem in end-stage renal disease (ESRD) patients. Ultrafiltration and hemodialysis lead to profound hemodynamic changes. The aim of this pilot study was to describe brain and hand oxygenation values in ESRD patients and their changes during hemodialysis. METHODS: Twenty-seven patients treated by chronic hemodialysis and 17 controls patients of the same age were included in the study. Regional saturation of oxygen (SrO2) was measured at the brain frontal lobe and at the hand with dialysis access using the INVOS 5100C. In 17 of ESRD patients, SrO2 was also monitored throughout hemodialysis. Finger systolic blood pressure and basic hemodialysis and laboratory data were collected. RESULTS: Dialysis patients had lower brain and also hand SrO2 values at rest (51.5 ± 10.9 vs. 68 ± 7%, p<0.0001 and 55 ± 16 vs. 66 ± 8%, p = 0.03, respectively). Both values further decreased during the first 35 minutes of hemodialysis (brain SrO2 to 47 ± 8%, p<0.0001 and hand to 45 ± 14%, p<0.0001, respectively). The brain SrO2 decrease was related to the ultrafiltration rate, the hand SrO2 decrease to the finger pressure and to blood hemoglobin. CONCLUSIONS: Chronic dialysis patients suffer from tissue ischemia and that even worsens after the beginning of hemodialysis. This observation may contribute to the understanding of cognitive deficit etiology.

Left Atrial Dysfunction in End-Stage Renal Disease Patients Treated by Hemodialysis.

BACKGROUND: Repeated inter-dialysis water retention contributes to the development of left ventricular hypertrophy and failure, which is responsible for significant mortality of end-stage renal disease (ESRD) patients. The left atrium has a thin wall, which makes it even more prone to preload changes. In the general population with heart failure with preserved ejection fraction (HFpEF), left atrial function is even worse than that in patients with reduced ejection fraction. We hypothesized that repeated water retention is related to left atrial dysfunction in ESRD patients treated by hemodialysis and that the expected changes would be related to the brain natriuretic peptide (BNP) levels. METHODS: Forty six patients were enrolled. Left atrial end-diastolic and end-systolic volumes and left atrial ejection fraction (LAEF) were recorded by echocardiography just before and just after dialysis and then analyzed offline. Moreover, BNP was analyzed also prior to dialysis and after. Effects of dialysis were tested using paired t test and the correlation analysis was applied to test associations. RESULTS: LAEF was inversely related to the dialysis vintage (r = -0.62, p = 0.001) and patient's age (r = -0.48, p = 0.005) and it did not increase after dialysis despite the decrease of left atrial volume. BNP was related to left atrial volume index (r = 0.45, p = 0.019) and to LAEF (r = -0.57, p = 0.003). CONCLUSIONS: LAEF is decreased especially in long-term dialyzed patients and does not improve after dialysis despite the decrease of left atrial volume. Inadequate contractility reserve of the left atrium is similar to the non-ESRD patients with HFpEF and might help explain the high prevalence of heart failure in ESRD patients.

[Theralite and multiple myeloma]. / Theralite a mnohocetný myelom.

Multiple myeloma associated with an increased FLC production causes renal failure (cast nephropathy) requiring dialysis. Theralite is a dialyser with a high cut-off membrane (HCO) - with large size pores that allow permeability for substances of molecular masses up to 45 kDa. The FLC concentrations over hemodialysis will significantly decrease and if hematological treatment is also effective, the FLC production will significantly fall as well. The aim of this comprehensive therapy is to improve the renal functions to such an extent that a substantial removal of FLC (70-90 %) is reached in patients and even interruption of dialysis therapy (50-75 %). The number of HD with this membrane rather varies in individual patients according to the literature (e.g. an average of 12 HDs/per 1 patient - 3-45). Our cohort comprised 17 patients aged 38-71 years, with 9 HDs per 1 patient, 10 patients (59 %) stopped the dialysis therapy and 7 remained on the dialysis programme. FLC removal reached 87 % in the whole cohort after the completed HDs with Theralite, but it specifically reached 93 % in the patients without further dialysis therapy, as opposed to 75 % in those who continued to undergo HD. No patient died when receiving HD with Theralite, in 4 complications occurred without causing interruption of the therapy. We assume that monitoring FLC concentrations before each dialysis may be of prognostic significance for patients including the length of treatment with an HCO membrane. Close cooperation with a hematologist is necessary.Key words: cast nephropathy - FLC - HCO membrane - multiple myeloma - kidney failure - Theralite.