Improved cardiovascular variables during acetate free biofiltration. Online hemodiafiltration versus acetate-free biofiltration: a prospective crossover study. Preservation of residual renal function in dialysis patients: effects of dialysis-technique-related factors. Cardiovascular response during hemodialysis and hemofiltration: thermal, membrane, and catecholamine influences. A prospective comparison of bicarbonate dialysis, hemodiafiltration, and acetate-free biofiltration in the elderly. Acetate-free biofiltration versus bicarbonate haemodialysis in the treatment of patients with diabetic nephropathy: a cross-over multicentric study. Clinical improvement by increased frequency of on-line hemodialfiltration. A randomized cross-over comparison of the hemodynamic response to intermittent hemodialysis and continuous hemofiltration in ICU patients with acute renal failure. Comparison between hemofiltration and hemodiafiltration in a long-term prospective cross-over study. A randomized clinical trial of continuous versus intermittent dialysis for acute renal failure. High-volume hemofiltration after out-of-hospital cardiac arrest: a randomized study. Comparison of hemodialysis and hypertonic hemodiafiltration on cardiac function [corrected]. Effects of different membranes and dialysis technologies on patient treatment tolerance and nutritional parameters. The Italian Cooperative Dialysis Study Group. Pulmonary-artery versus central venous catheter to guide treatment of acute lung injury. A randomized controlled trial comparing intermittent with continuous dialysis in patients with ARF. Long-term quality of life and hospital mortality in patients treated with intermittent or continuous hemodialysis for acute renal and respiratory failure. Tolerance of hemodialysis: a randomized prospective trial of high-flux versus conventional high-efficiency hemodialysis. The rapid infusion system: a superior method for the resuscitation of hypovolemic trauma patients. Biocompatibility and performance of a modified cellulosic and a synthetic high flux dialyzer. A randomized crossover comparison between cellulose triacetate and polysulphon. Hypertonic saline and dextran after coronary artery surgery mobilises fluid excess and improves cardiorespiratory functions.
Acetate free biofiltration (AFB) provides a well-tolerated and efficient renal replacement therapy. Replacement of most of the acetate by bicarbonate in standard hemodialysis has resulted in a decrease in intradialytic hypotensive episodes. This has been attributed to a decrease in the acetate-induced impairment of myocardial contractility. The aim of the present study was to investigate whether the total absence of acetate in AFB would further enhance dialysis stability and improve cardiovascular status.
                In a long-term, randomized trial we included 11 patients on AFB and 9 patients on bicarbonate hemodialysis (HD) for one year. Patients were matched for age, sex and urea reduction rate, but not for the presence of hypertension or cardiovascular history. During each dialysis session blood pressure was measured automatically and the presence of significant hypotension was recorded. Antihypertensive medication was registered every three months. Before and at the end of the study M-mode echocardiography was performed and left ventricular mass index (LVMi) was calculated. Every six months serum lipids were measured.
                At baseline, mean arterial pressure (MAP) before and after dialysis, the percentage of hypotensive dialyses, LVMi and serum lipids did not differ between AFB and HD. Pre-dialysis MAP decreased in AFB (from 112.5 to 107 mmHg) and increased in HD (from 101.7 to 105.3 mmHg; p = 0.01, HD versus AFB). Postdialysis MAP remained stable in both groups (AFB 91.6 mmHg at 0 months and 90.6 mmHg at 12 months, for HD respectively 83.9 and 86.5 mmHg, NS). The percentage of hypotensive dialyses did not differ significantly between the groups during the study. LVMi decreased in AFB from 195.4 to 162.1 gr/m2 and increased in HD patients from 153.8 to 182.5 gr/m2 (p = 0.03 HD versus AFB). The number of antihypertensive medications per patient did not differ between groups. Serum lipids remained unchanged during the trial.
                In conclusion, AFB provided better control of pre-dialysis MAP compared to HD, and stable postdialysis MAP. The percentage of dialysis sessions with hypotension did not differ. LVMi decreased significantly in AFB, but rose in HD. Online hemodiafiltration (online HDF) and acetate-free biofiltration (AFB) are 2 innovative renal replacement therapies. Convincing evidence has shown that both techniques are superior to conventional hemodialysis in many aspects. The aim of the present investigation was to compare online HDF and AFB in 12 stable maintenance hemodialysis patients in a prospective, randomized crossover trial. Twelve stable dialysis patients, age 49.7 +/- 11.3 years and on dialysis for 83.5 +/- 76.7 months, were treated prospectively and randomly by either AFB, predilution HDF (pre-HDF), or postdilution HDF (post-HDF) for a total of 36 weeks using exclusively F60S high-flux dialyzers. Routine blood biochemical tests, bone metabolism parameters, and clearance for both small and larger molecular weight substances were measured at defined intervals. During the trial period inter- and intradialysis symptoms, e.g., hypotensive episodes and intradialysis arterial blood gas analyses, were recorded. Both online HDF and AFB were well accepted by the overwhelming majority of patients and also by the dialysis staff. Pretreatment sodium, total and ionized calcium, chloride, bicarbonate, and urea did not differ within or between the 3 treatment groups. Potassium increased slightly in HDF patients while phosphate and beta2-microglobulin (beta2-M) decreased in all groups. After dialysis, AFB patients exhibited a significantly higher bicarbonate concentration and lower potassium level when identical potassium concentrations in dialysate were used. Patients receiving AFB manifested less intradialysis partial pressure of oxygen drop and partial pressure of carbon dioxide rise than those on HDF treatments. HDF treatments could afford higher single-pool and double-pool Kt/V, higher effective urea and beta2M clearance, and lower total interdialysis symptom scores than the AFB treatment method. While bone metabolism parameters did not differ between the 3 dialysis modalities, some parameters such as deoxypyridinoline in HDF and osteocalcin, pyridinoline, and deoxypyridinoline in AFB deteriorated at the end of the crossover study. Aluminum concentration decreased progressively to about one-third of prestudy values at the end of the study with all 3 treatments. AFB was associated with a lower predialysis mean arterial pressure (MAP), a smaller drop in MAP during treatment, and similar hypotension episodes compared with the 2 HDF treatments. Albumin concentration showed a trend to decrease during the first 2 months of the trial period followed by a slight increase thereafter but still significantly lower than initial value at the end of crossover. Both online HDF and AFB share most of the features of optimal renal replacement therapy. Online HDF is superior to AFB in such aspects as increased delivered dialysis dose both for small and larger molecular weight toxins and less interdialysis symptoms. On the other hand, AFB is associated with a smaller effect on arterial blood gas values and improved intradialysis hemodynamic tolerance. Some dialysis-related symptoms and complications in the case of our AFB practice could be attributable, at least in part, to low dialysate calcium level. Residual renal function (RRF) is of paramount importance to dialysis adequacy, morbidity, and mortality, particularly for long-term continuous ambulatory peritoneal dialysis (CAPD) patients. Residual renal function seems to be better preserved in patients on CAPD than in hemodialysis (HD) patients. We analyzed RRF in 45 patients with end-stage renal disease (ESRD), commencing either CAPD or HD, to prospectively define the time course of the decline in RRF, and to evaluate dialysis-technique-related factors such as cardiovascular stability and bioincompatibility.
                Single-center prospective investigation in parallel design with matched pairs.
                Fifteen patients starting CAPD and 15 matched pairs of patients commencing HD were matched according to cause of renal failure and RRF. Hemodialysis patients were assigned to two dialyzer membranes differing markedly in their potential to activate complement and cells (bioincompatibility). Fifteen patients were treated exclusively with the cuprophane membrane (bioincompatible) and the other 15 patients received HD with the high-flux polysulfone membrane (biocompatible).
                Residual renal function was determined at initiation of dialytic therapy and after 6, 12, and 24 months. Dry weight (by chest x ray and diameter of the vena cava) was closely recorded throughout the study, and the number of hypotensive episodes counted.
                Residual renal function declined in both CAPD and HD patients, although this decline was faster in HD patients (2.8 mL/minute after 6 months and 3.7 mL/min after 12 months) than in CAPD patients (0.6 mL/min and 1.4 mL/min after 6 and 12 months respectively). It declined faster in patients with bioincompatible than with biocompatible HD membranes (3.6 mL/min vs 1.9 mL/min after 6 months). Eleven percent of the HD sessions were complicated by clinically relevant blood pressure reductions, but there were no differences between the two dialyzer membrane groups. None of the CAPD patients had documented hypotensive episodes. None of the study patients suffered severe illness or received nephrotoxic antibiotics or radiocontrast media.
                The better preservation of RRF in stable CAPD patients corresponded with greater cardiovascular stability compared to HD patients, independently of the membrane used. Furthermore, there was a significantly higher preservation of RRF in HD patients on polysulfone versus cuprophane membranes, indicating an additional effect of biocompatibility, such as less generation of nephrotoxic substances by the membrane. Thus, starting ESRD patients on HD prior to elective CAPD should be avoided for better preservation of RRF. Nine patients on regular dialysis were studied, in a cross-over format comparing hemodialysis (HD) and hemofiltration (HF), to identify potential mechanisms of the disparate hemodynamic responses. Dialysis and substitution fluid composition (high sodium, acetate), treatment time, fluid loss rate, and membrane type (AN 69) were matched. Cardiac output was determined by changes in thoracic electrical bioimpedance. Cardiac output remained stable during HF but increased during HD (p < 0.001, HD vs. HF), despite a parallel reduction in stroke volume. The heart rate response was significantly greater during HD relative to HF (p < 0.01). Systemic vascular resistance remained stable during HF but decreased significantly during HD (p < 0.05). Although there was a modest fall during HD, the difference in blood pressure at the end of treatment between HD and HF was not significant. Comparable increases in body temperature were observed during both treatments. Plasma catecholamines increased in parallel during HD and HF and following orthostatic stimulation at the end of treatment, and extracorporeal catecholamine clearances were similar. The values for serum sodium, total CO2, anion gap, potassium, and hematocrit at the end of treatment were similar, whereas total serum calcium was significantly greater following HD. There were no significant differences in indices of myocardial contractility or central blood volume. These results suggest that the disparate hemodynamic responses to fluid and solute removal during HD and HF can be dissociated from changes in osmolality or venous tone, membrane bioincompatibility, thermal stress, or differences in acetate delivery or catecholamine release. The explanation for the disparate hemodynamic responses between these two treatment modalities remains unclear. A role for an as yet unidentified vasodilatory substance generated during dialysate exposure, or convectively removed during hemofiltration, remain intriguing possibilities. Hemodiafiltration (HDF) and more recently acetate-free biofiltration (AFB) have shown good blood purification and cardiovascular stability in young and middle-aged hemodialysis patients. It is not clear if this is also valid for elderly patients. Twelve patients aged more than 70 years (mean age +/- SD, 76 +/- 4 years) on regular dialysis for at least 5 months were treated with bicarbonate dialysis (BD), HDF, or AFB in a randomized sequence and prospectively followed for 6 months (72 dialysis sessions/patient) for each procedure. The dialysis solution (containing bicarbonate), blood flow rate, and dialysate flow rate were the same with all the methods. During HDF and AFB solutions containing bicarbonate at a concentration of 27 to 30 mEq/L and 145 mEq/L, respectively, were infused postdilution at a rate of 66 +/- 7 mL/min and 2.81 +/- 0.12 L/hr, respectively. During the period of observation we evaluated the number of intradialytic hypotensions, the episodes of nausea, vomiting, headache (dialysis intolerance), body weight, the interdialysis weight gain, the duration of the dialysis session, the number of hospitalizations/patient, and the length of hospitalization/patient. At the end of each observation period we determined: Kt/V, protein catabolic rate, acid base balance, serum creatinine, serum calcium, serum phosphorus, alkaline phosphatases, and serum intact parathyroid hormone. After the switch from BD to either HDF or AFB, the results have shown a significant reduction of dialysis hypotension episodes (18 percent on BD, 14 percent on HDF, and 13 percent on AFB; BD v HDF, P = 0.001; BD v AFB, P = 0.0001; and HDF v AFB, P = NS) and of dialysis intolerance (3.3 percent on BD, 1.3 percent on HDF, and 1.1 percent on AFB; BD v HDF, P = 0.021; BD v AFB, P = 0.019; and HDF v AFB, P = NS). Kt/V improved significantly after the switch from BD to either HDF or AFB (1.17 +/- 0.06 on BD, 1.32 +/- 0.12 on HDF, and 1.32 +/- 0.13 on AFB; BD v HDF, P = 0.021; BD v AFB, P = 0.003; HDF v AFB, P = NS). Protein catabolic rate also improved in HDF and AFB compared with BD (0.90 +/- 0.12 on BD, 1.03 +/- 0.15 on HDF, and 1.04 +/- 0.14 on AFB; BD v HDF, P = 0.001; BD v AFB, P = 0.009; and HDF v AFB, P = NS). AFB showed a better correction of acidosis compared either with BD or HDF (serum bicarbonate, 20.3 +/- 1.1 mEq/L on BD, 20.8 +/- 2.2 mEqL on HDF, and 22.2 +/- 2.4 mEq/L on AFB; BD v HDF, P = NS; BD v AFB, P = 0.01; and HDF v AFB, P = 0.030). The other parameters observed did not differ. In conclusion HDF and AFB show a better dialysis efficiency and a better hemodynamic tolerance compared with BD. This fact is associated with an improvement in protein intake as assessed by kinetic criteria. Acetate-free biofiltration has the further advantage of a better control of the acid-base balance compared with BD and HDF. HDF and AFB are useful dialytic options to traditional BD hemodialysis even in patients older than 70 years. Morbidity and mortality rates in diabetic patients on regular dialysis treatment (RDT) are higher than in non-diabetic-subjects on RDT. Moreover, diabetic patients experience an intradialitic morbidity unacceptably higher than in patients with other causes of terminal renal failure. The aim of the present investigation was to compare standard bicarbonate haemodialysis (BHD) with acetate-free biofiltration (AFB) in a group of 41 diabetic patients stable on dialysis treatment for 25 +/- 22 months.
                Twenty-four type II and 17 type I diabetic patients, all requiring insulin therapy, were included and were followed for 1 year in a 6-month cross-over randomized study for both methods. The analysis was carried out on dialysis symptoms, interdialysis symptoms, and nutritional status, and the multivariate analysis of variance for repeated measures on the same subjects in the two techniques was used.
                AFB significantly reduced dialytic and extradialytic symptoms (P=0.003 and 0.001 respectively). Cardiovascular collapses decreased by 43%, and other dialysis symptoms showed a similar trend (-35%). The interdialysis symptoms decreased by 28% and were accompanied by an increase in subjective wellbeing (39%) when patients were switched from traditional haemodialysis to AFB. Acid base control was better with AFB (P=0.01), both at the beginning and during the session. Slightly significant differences were also obtained for Kt/V (AFB 1.48 +/- 0.29 vs BHD 1.38 +/- 0.30), while no significant difference was noted with respect to sodium mass balance, nutritional status, calorie-protein intake, nPCR, blood glucose profile, and insulin requirements. The number of hospital admissions and the mortality rate, which were much lower during the AFB than the BHD period, were not analysed statistically.
                AFB allows better control of some metabolic aspects, reduces intra- and extradialysis symptoms, and improves patient quality of life. Whether the long-term prognosis can be improved by AFB remains to be established with further studies. In spite of the better efficiency of on-line hemodiafiltration (HDF) compared with conventional hemodialysis (HD), it is relatively expensive. The aim of this study was to assess the advantages in the biochemical, hemodynamic and clinical effects in uremic patients treated with on-line HDF and with different frequencies of combination high-flux HD.
                One hundred eleven patients were divided into four groups receiving different frequencies of on-line HDF (thrice, twice, once per week) and high-flux HD.
                Hemodynamic parameters including maximum drop of systolic blood pressure, episodes of symptomatic hypotension and mean saline infusion volumes during dialysis were reduced when frequencies of on-line HDF were increased. Significant improvements in urea kinetic were observed when frequencies of on-line HDF were increased. On-line HDF significantly reduced the amount of erythropoietin needed and improved intra- and inter-dialysis symptoms, physical well-being, menstruation and skin pigmentation when frequency of HDF is increased to three time per week.
                On-line HDF offers a better cardiovascular stability and clinical improvement. Thrice weekly on-line HDF offers a significant benefit when compared with lower frequencies of HDF per week and high-flux HD. To compare the hemodynamic response of ICU patients with acute renal failure of a 24-h continuous arteriovenous hemofiltration (CAVH) and that of patients with a 4-h intermittent hemodialysis (HD).
                Cross-over randomized clinical trial. The two periods to be compared were a 24-h CAVH and the 24-h encompassing a 4-h HD. These two periods were separated by a 24-h wash-out period.
                Ten bed medicosurgical ICU of a tertiary care center in Paris, France.
                Inclusion criterion was the requirement of replacement therapy for acute renal failure in patients already submitted to mechanical ventilation.
                CAVH was performed with Ringers' lactate used for restitution and infused before the hemofilter. The ultrafiltrate output was maintained at around 15 ml/min. HD was performed with a bicarbonate-buffered dialysate.
                Mean arterial pressure (MAP), use of adrenergic drugs, and change in body weight during each period.
                Twenty-seven consecutive patients were included, 15 CAVH-HD and 12HD-CAVH. CAVH and HD allowed the same metabolic efficacy. No hemodynamic parameter (MAP, amount of adrenergic drugs, change in body weight) differed between the two methods.
                CAVH is equivalent to HD in terms of MAP and the use of vasopressive drugs and fluids. Establishing the superiority of CAVH would require carefully controlled studies assessing either outcome or changes in tissue oxygenation. The objective of the study was to compare the convective treatment modes, on-line hemofiltration (HF) and on-line hemodiafiltration (HDF), regarding cardiovascular tolerance and effects on blood pressure, when applied under similar conditions in stable dialysis patients.
                39 clinically stable dialysis patients were treated with HD for 6 months (run-in period), followed by HF and HDF in random order for 2x6 months. Similar biocompatibility (same membrane and fluid quality), similar treatment time and urea Kt/V were achieved using AK100/200 ULTRA machines, polyamide membranes in low-flux and high-flux versions and appropriate adjustment of blood flow rate (Qb) and dilution ratio (Qb/Qinf). Predilution was used for HDF (target dilution ratio = 2/1 ) as well as for HF (target dilution ratio = 1/1).
                30 patients completed the study; 5 dropped out for non-study related reasons and 4 for non-compliance. Treatment with HF in comparison to HDF showed fewer hypotension episodes during the sessions per patient and month (HF: 0.5, HDF 1.1; p = 0.017), less plasma expander administration per patient and month (HF: 35.9 ml, HDF: 103.1 ml; p = 0.035), fewer episodes of intra-session headache (HF: 0.1, HDF: 0.4; p = 0.06), and higher pre-session MAP (HF: 98.4 mmHg, HDF: 93.8 mmHg; p = 0.037). No significant difference was found in inter-treatment weight gain, post-session MAP, or pre-session plasma sodium.
                HF and HDF provide good control of intra-session symptoms and blood pressure in stable patients. Treatment with HF resulted in a significant reduction in intra-session hypotension and a slight but significant increase in pre-session MAP, caused by an increase in systolic BP without any effect on the prevalence of hypertension or the dose of antihypertensive drugs, all compared to HDF. Acute renal failure (ARF) requiring dialysis in critically ill patients is associated with an in-hospital mortality rate of 50 to 80%. The worldwide standard for renal replacement therapy is intermittent hemodialysis (IHD). Continuous hemodialysis and hemofiltration techniques have recently emerged as alternative modalities. These two therapies have not been directly compared.
                A multicenter, randomized, controlled trial was conducted comparing two dialysis modalities (IHD vs. continuous hemodiafiltration) for the treatment of ARF in the intensive care unit (ICU). One hundred sixty-six patients were randomized. Principal outcome measures were ICU and hospital mortality, length of stay, and recovery of renal function.
                Using intention-to-treat analysis, the overall ICU and in-hospital mortalities were 50.6 and 56.6%, respectively. Continuous therapy was associated with an increase in ICU (59.5 vs. 41.5%, P < 0.02) and in-hospital (65.5 vs. 47.6%, P < 0.02) mortality relative to intermittent dialysis. Median ICU length of stay from the time of nephrology consultation was 16.5 days, and complete recovery of renal function was observed in 34.9% of patients, with no significant group differences. Despite randomization, there were significant differences between the groups in several covariates independently associated with mortality, including gender, hepatic failure, APACHE II and III scores, and the number of failed organ systems, in each instance biased in favor of the intermittent dialysis group. Using logistic regression to adjust for the imbalances in group assignment, the odds of death associated with continuous therapy was 1.3 (95% CI, 0.6 to 2.7, P = NS). A detailed investigation of the randomization process failed to explain the marked differences in patient assignment.
                A randomized controlled trial of alternative dialysis modalities in ARF is feasible. Despite the potential advantages of continuous techniques, this study provides no evidence of a survival benefit of continuous hemodiafiltration compared with IHD. This study did not control for other major clinical decisions or other supportive management strategies that are widely variable (for example, nutrition support, hemodynamic support, timing of initiation, and dose of dialysis) and might materially influence outcomes in ARF. Standardization of several aspects of care or extremely large sample sizes will be required to answer optimally the questions originally posed by this investigation. The study examined the effect of isovolumic high-volume hemofiltration (HF) alone or combined with mild hypothermia (HT) on survival after out-of-hospital cardiac arrest (OHCA) with initial ventricular fibrillation or asystole.
                Global inflammation in response to whole-body ischemia-reperfusion is common after OHCA and may worsen the overall prognosis.
                Sixty-one patients admitted between May 2000 and March 2002 in the intensive care units of two hospitals in France were randomized to one of three groups: control, HF (200 ml/kg/h over 8 h) or HF+HT (32 degrees C for 24 h) induced by cooling the HF substitution fluid. Standard supportive care was provided in all three groups. The primary end point was survival with a follow-up time of six months. The effect of HF on death by intractable shock was the secondary end point.
                The six-month survival curves of the three groups were significantly different, with better survival in the HF group (p = 0.026) and in the HF+HT group (p = 0.018). After adjustment on baseline characteristics of cardiac arrest, HF (with or without HT) was associated with improved survival (logistic regression odds ratio, 4.4; 95% confidence interval [CI], 1.1 to 16.6). Compared to control group, the relative risk of death by intractable shock was 0.29 (95% CI, 0.09 to 0.91) in the HF+HT group and 0.21 (95% CI, 0.05 to 0.85) in the HF group.
                The HF may improve the overall prognosis after resuscitation from OHCA. Combination of HF with mild HT is feasible and should be evaluated in larger trials. This study compared the acute and chronic effects on cardiac function of treatment with hypertonic hemodiafiltration (H HDF) and hemodialysis (HD). Cardiac function was assessed before, during and after a run of H HDF and HD using echocardiography and impedance cardiography in 10 patients in a randomized cross-over sequence, two months after stabilization on each treatment. Blood biochemistry was performed before and after each run. Ejection fraction and fractional shortening were significantly higher before the H HDF run, compared to the HD run, and this difference persisted during and after the treatment runs (both P less than 0.05). There was a corresponding significant difference in the increase of the velocity of circumferential fiber shortening and in the reduction of end systolic diameter during and after H HDF (P less than 0.05). Heart rate, stroke volume, cardiac output, systemic vascular resistance and mean arterial pressure did not differ significantly between the two treatments. Plasma calcium and bicarbonate were significantly higher (P less than 0.03) at the start of H HDF and this difference was enhanced at the end of the run. In conclusion, H HDF compared with HD, is associated with a better myocardial function in both the short and long term treatments. The evidence suggests that this may be due to improved levels of plasma calcium, bicarbonate, and/or the removal of an as yet unidentified myocardial toxin. There is increasing evidence that the biochemical and cellular phenomena induced by blood/ membrane/dialysate interactions contribute to dialysis-related intradialytic and long-term complications. However, there is a lack of large, prospective, randomized trials comparing biocompatible and bioincompatible membranes, and convective and diffusive treatment modalities. The primary aim of this prospective, randomized trial was to evaluate whether the use of polysulfone membrane with bicarbonate dialysate offers any advantage (in terms of treatment tolerance, nutritional parameters and pre-treatment beta-microglobulin levels) over a traditional membrane (Cuprophan). A secondary aim was to assess whether the use of more sophisticated methods consisting of a biocompatible synthetic membrane with different hydraulic permeability at different ultrafiltration rate (high-flux hemodialysis and hemodiafiltration) offers any further advantages. Seventy-one Centers were involved and stratified according to the availability of only the first two or all four of the following techniques: Cuprophan hemodialysis (Cu-HD), low-flux polysulfone hemodialysis (LfPS-HD), high-flux polysulfone high-flux hemodialysis (HfPS-HD), and high-flux polysulfone hemodiafiltration (HfPS-HDF). The 380 eligible patients were randomized to one of the two or four treatments (132 to Cu-HD, 147 to LfPS-HD, 51 to HfPS-HD and 50 to HfPS-HDF). The follow-up was 24 months. No statistical difference was observed in the algebraic sum of the end points between bicarbonate dialysis with Cuprophan or with low-flux polysulfone, or among the four dialysis methods under evaluation. There was a significant decrease in pre-dialysis plasma beta 2-microglobulin levels in high-flux dialysis of 9.04 +/- 10.46 mg/liter (23%) and in hemodiafiltration of 6.35 +/- 12.28 mg/liter (16%), both using high-flux polysulfone membrane in comparison with Cuprophan and low-flux polysulfone membranes (P = 0.032). The significant decrease in pre-dialysis plasma beta 2-microglobulin levels could have a clinical impact when one considers that beta 2-microglobulin accumulation and amyloidosis are important long-term dialysis-related complications. The balance between the benefits and the risks of pulmonary-artery catheters (PACs) has not been established.
                We evaluated the relationship of benefits and risks of PACs in 1000 patients with established acute lung injury in a randomized trial comparing hemodynamic management guided by a PAC with hemodynamic management guided by a central venous catheter (CVC) using an explicit management protocol. Mortality during the first 60 days before discharge home was the primary outcome.
                The groups had similar baseline characteristics. The rates of death during the first 60 days before discharge home were similar in the PAC and CVC groups (27.4 percent and 26.3 percent, respectively; P=0.69; absolute difference, 1.1 percent; 95 percent confidence interval, -4.4 to 6.6 percent), as were the mean (+/-SE) numbers of both ventilator-free days (13.2+/-0.5 and 13.5+/-0.5; P=0.58) and days not spent in the intensive care unit (12.0+/-0.4 and 12.5+/-0.5; P=0.40) to day 28. PAC-guided therapy did not improve these measures for patients in shock at the time of enrollment. There were no significant differences between groups in lung or kidney function, rates of hypotension, ventilator settings, or use of dialysis or vasopressors. Approximately 90 percent of protocol instructions were followed in both groups, with a 1 percent rate of crossover from CVC- to PAC-guided therapy. Fluid balance was similar in the two groups, as was the proportion of instructions given for fluid and diuretics. Dobutamine use was uncommon. The PAC group had approximately twice as many catheter-related complications (predominantly arrhythmias).
                PAC-guided therapy did not improve survival or organ function but was associated with more complications than CVC-guided therapy. These results, when considered with those of previous studies, suggest that the PAC should not be routinely used for the management of acute lung injury. (ClinicalTrials.gov number, NCT00281268.).
                Copyright 2006 Massachusetts Medical Society. Despite the widespread use of continuous renal replacement therapy in critically ill patients with acute renal failure (ARF), there are few data supporting its benefits over conventional intermittent hemodialysis (IHD). We sought to analyze differences in survival between modalities in a study that compared continuous venovenous hemodialysis (CVVHD) with IHD.
                Eighty critically ill patients with ARF requiring dialysis were randomized after stratification by severity of illness to treatment with CVVHD or IHD.
                There were no differences in survival or renal recovery between groups. In patients who died, mean survival time was 10.7 +/- 11.2 days for the IHD group versus 14.3 +/- 16.1 days for the CVVHD group (P = not significant). There was greater net volume removal in the CVVHD group during 72 hours. Declines in urine output during 72 hours were similar between groups. Mean arterial pressure off and on dialysis therapy was analyzed retrospectively. There was a significant decrease in mean arterial pressure for patients on IHD therapy not seen in those on CVVHD therapy, but this did not lead to a survival advantage.
                Despite greater volume control, CVVHD did not lead to an improvement in survival, preservation of urine output, or renal recovery compared with IHD in patients with ARF. To describe long-term quality of life, intensive care, and hospital mortality in patients with acute renal and respiratory failure treated with one of two methods of renal replacement therapy (RRT).
                Cross-sectional survey of long-term survivors from a prospective observational study of two methods of RRT.
                A combined surgical and medical intensive care unit in a university hospital.
                One hundred and twenty-six patients with acute renal and respiratory failure who required treatment with RRT and mechanical ventilation. Interventions. (1) RRT for acute renal failure was with either continuous hemodialysis with ultrafiltration using biocompatible membranes and prostacyclin and heparin anticoagulation (CHDF) or intermittent hemodialysis using cuprophane membranes and heparin anticoagulation (IHD); (2) Health-related quality of life in long-term survivors was assessed with the SF-36 (HRQL) questionnaire.
                (1) There was no difference in ICU mortality (73.5% [39/53] IHD vs. 71.8% [46/64] CHDF, P = NS) or hospital mortality (83% [44/53] IHD vs. 76.5% [49/64] CHDF, P = NS) between the two RRT treatment groups. By 1999, there were 16 surviving patients; (2) Twelve of these survivors completed SF-36 forms (10 CHDF vs. 2 IHD). The overall physical health summary score and scores for seven of the health domains were significantly reduced. The mental health summary score and the domain mental health score did not differ from the general population.
                (1) The method of RRT used in ICU patients with ARF had no influence on survival; (2) The long-term survivors of multi-organ failure have poor physical health. Hemodialysis is frequently complicated by hypotension and associated symptoms. It has been suggested that these symptoms may be related to the biochemical changes caused by cellulosic dialysis membranes. In this study, a prospective randomized crossover trial was conducted comparing the incidence of hypotension and acute symptoms during dialysis with large-surface-area (1.6 m2) cellulosic (cuprophane [CUP]) and noncellulosic (polyacrylonitrile [PAN], AN69) membranes. Dialyzers were used for a single use only. There was no difference in predialysis BUN, predialysis blood pressure, intradialytic weight gain, blood flow, dialysis efficiency (urea reduction), dialysis duration, hematocrit, or erythropoietin dose between the two study phases. When these clinical characteristics were matched, there was no difference in the number of episodes of hypotension (CUP, 19 +/- 3; PAN, 22 +/- 3; P = not significant [NS]). The incidence of symptomatic hypotension, as reflected by the number of episodes of hypotension requiring more than 100 mL of saline for correction, was also not different between study phases (CUP, 10 +/- 1; AN69, 11 +/- 2; P = NS). The incidence of intradialytic symptoms, including emesis, cramping, headache, angina, pruritus, and bronchospasm, was similar during the two study phases (CUP, 11 +/- 2; AN69, 10 +/- 1; P = NS). It was concluded that noncellulosic membranes do not offer any significant advantage over cellulosic membranes in reducing the acute complications of hemodialysis. The rapid infusion system (RIS), which can deliver fluids/blood products rapidly at precise rates and normothermic conditions, was compared with conventional fluid administration (CFA) in a randomized study of 36 hypovolemic trauma patients. Admission stratification criteria of the groups were similar relative to age, Glasgow Coma Score (GCS), Injury Severity Score (ISS) and plasma lactate. Despite the lack of difference in blood loss between the 24-h survivors of the two groups, the CFA group required greater total fluids (23.6/20.21), red blood cells (5.5/4.61), fresh frozen plasma (FFP) (2.8/1.91), platelets (523/204 ml), and crystalloids (12.9/10.61). Lactate levels were lower in the RIS group at virtually all times from hours 1 to 24 (4.3/5.3 mM/l, t-value = 3.3, DF = 279, P = 0.001). Post-admission hypothermia was greater in the CFA group at all times during the first 24 h (35.2/36.4 degrees C, t-value = 5.6, DF = 250, P = 0.001). The mean partial thromboplastin time was significantly higher in the CFA group (47.3/35.1 s, t-value = 3.1, DF = 279, P = 0.002). The PTT and PT were related to the degree of lactic acidosis (P = 0.0001) and hypothermia (P = 0.001) but not to the amount of FFP given (P = 0.14). The hospital costs, days in the ICU, and days on the ventilator were greater for the CFA group, as was the incidence of pneumonia (0/11 vs. 6/17; P = 0.03). Hypovolemic trauma patients resuscitated with the RIS needed fewer fluid/blood products and had less coagulopathy; more rapid resolution of hypoperfusion acidosis; better temperature preservation; and fewer hospital complications than those resuscitated with conventional methods of fluid/blood product administration. The biocompatibility and performance of two high flux membranes (modified cellulosic: cellulose-triacetate (CTA), and a synthetic material: polysulphon [PS]) were assessed in 31 stable patients on hemodialysis (HD) in a randomized crossover study. Parameters evaluated included leukocytes, complement activation products C3a and C5a, cytokines, lymphocyte subpopulations, urea, creatinine, phosphate, and beta 2 microglobulin. Considering biocompatibility, the drop in the number of leukocytes was more pronounced during CTA HD compared with PS (p = 0.045), although both were low in comparison with cuprammonium dialysis in the same patients, as observed during a separate study. Both membranes induced a low and transient state of complement activation. Interleukin 1 beta and interleukin 6 could not be detected at all, whereas tumor necrosis factor alpha levels were marginally elevated before and after HD with both membranes. During the first 30 min of HD with either membrane, the numbers of CD8+ cells decreased significantly, resulting in an increase in the CD4/CD8 ratios; in addition, the number of NK cells decreased. Performance, as measured by extraction ratios for small molecular weight solutes and Kt/V urea, was significantly better during CTA dialysis (p < 0.001), but almost similar after correction for membrane surface area. On the basis of these data, it seems justified to conclude that, whereas biocompatibility of the PS dialyzer appeared slightly superior to CTA, performance of both dialyzers was comparable. Extracorporeal circulation induces increased capillary permeability with fluid leakage into the interstitial space, resulting in positive fluid balance and intravascular hypovolaemia. Hypertonic saline 75 mg.ml-1 in dextran 70, 60 mg.ml-1 (HSD) seems to be of benefit in patients with impaired perfusion. The purpose of the study was to investigate the effects of HSD infusion on fluid balance and cardiorespiratory functions just after the end of cardiac surgery.
                Twenty patients with 3-vessel coronary artery disease undergoing elective coronary artery bypass surgery were studied. A standard regimen for anaesthesia, extracorporeal circulation and monitoring was used. The patients were allocated to receive just after the end of surgery either HSD or isotonic saline (4 ml.kg-1 during 30 min) at random in a double-blind single infusion. Ringer's acetate solution was added as needed to stabilise haemodynamics postoperatively.
                HSD caused mobilisation of the retained intraoperative fluid excess, and increased diuresis. Despite reduced need for extra fluid and a decreased cumulative fluid balance, after HSD infusion patients had increased filling pressures of the heart and improved cardiac output. HSD infusion also induced reduced intrapulmonary venous admixture and improved PaO2 in the early postoperative period.
                The present study documents that infused hypertonic saline with dextran just after the end of cardiac surgery resulted in mobilisation of the intraoperative fluid excess with increased urine output in the early postoperative period and improved gas exchange. Despite reduced need for extra i.v. fluid and decreased cumulative fluid balance, after HSD infusion the patients had increased filling pressures of the heart with improved cardiac output.
We were unable to demonstrate whether convective modalities (either HF, HDF or AFB) have significant advantages over HD with regard to clinically important outcomes of mortality, dialysis-related hypotension and hospitalisation. More adequately-powered good quality RCTs assessing clinically important outcomes (mortality, hospitalisation, quality of life) are needed.