The Research About Use Of Continuous On-line Blood Volume Monitoring To Estimation Of 'Dry Weight' In Hemodialysis Patients

Objective: Reducing fluid overload, managing optimal fluid status in hemodialysis patients is one of the objective on long-term hemodialysis therapy. The setting of dry weight is verified through evaluation of clinical symptom, for example there are not edema, left ventricular hypertrophy, pulmonary edema, pericardial effusion, thorax effusion and blood pressure value in normal in dialysis patients, they feel comfortable. Underestimation of dry weight leads to hypovolemia induced muscle cramps, even hypotension, because fluid removal by ultrafiltration has been indicate, which is beyond of plasma volume recovery. Overestimation of dry weight leads to hypertension, left ventricular hypertrophy and pulmonary edema complication. Now there are many reports about the research for techniques to detect variation of blood volume, which can feedback the information of the patients'blood volume and hemodynamics. It offer a safe, innocuous technique to estimate dry weight according to blood volume status, in order to prevent from complication, decrease mortality and improve standard of living. At the same time we make the comparison between the blood volume monitor and a standard reference method involving calculation of relative blood volume from serial measurements of haemoglobin, which evince that the blood volume monitor can detect variation of blood volume continuously, therefore the blood volume monitor can take place of a standard reference method. Methods 1 24 patients with maintenance hemodialysis, whose ages were from 41 to 80 years, and mean age was 62.17±12.36 years, were selected in our blood purification center. Patients we selected include 9 patients of hypertension, 6 patients of chronic glomerulonephritis,4 patients of chronic pyelonephritis, 1 patient of renal cell carcinoma, double renal cut, 1 patient of drug-induced interstitial nephritis, and 1 patient of mult-sac renal. They all accepted hemodialysis therapy for more than 6 month. 2 24 patients with maintenance hemodialysis were divided into eligible group and below the mark group according to clinic standard of 'dry weight'. There were 8 patients in eligible group and 16 patients in below the mark group. Then two group were divide into group a(Hb>8g/dl) and group b (Hb<8g/dl) according to the concentration of haemoglobm secondly. 3 We recorded the parameter of the relative blood volume (RBV) obtained by the blood volume monitor (BVM) at pre-dialytic, two hours after dialytic and post dialytic. △BVcan be obtained according to △B V= 1-RBV 后。At the same time 1 ml blood was taken from the arterial lines, and was withdrawn into a mini-cuvette manually with a pipette. The blood was centrifuged for at least 30 min at 3 000 r.p.m. No further anticoaghulant was used, and the haematocrit was not corrected for trapped water. The number was achieved with double readings, noted Hct0,Hct1 and Hct2. 4 △'BV can obtained according to △BV =(Hctafter-Hctbefore)/Hctafter. The △'BV obtained by the monitor was compared with the △BV obtained by the standard reference method. 5 BWC and RBV were obtained by the blood volume monitor (BVM) at pre-dialytic and post dialytic. When patients of below the mark group were attained eligible dry weight by adjusting, they were in modificatory group. Data of three group were compared each other. Result: 1 There was no significantly difference between the two methods (P>0.05). The blood volume monitor can take place of the standard reference method. 2 The level of BWC in below the mark group was significantly higher than that in eligible group and modificatory group. There was significantly difference between them in statistics. (P<0.05) 3 There was no significantly difference of the BWC level between eligible group and modificatory group. (P>0.05)4 The level of △BV in below the mark group was significantly higher than that in eligible group and modificatory group. There was significantly difference between them in statistics. (P<0.05) 5 A positive correlation between BWC and △BV could be established in three groups. Concl...