Can Delivery Dialysis Dose Affect Survival of Acute Kidney Injury Patients?

Intensity of dialysis dose in acute kidney injury (AKI) might benefit critically ill patients. The aim of this study was to evaluate the effect of intermittent hemodialysis (IHD) dose on mortality in patients with AKI. Methods: Prospective observational study was performed on AKI patients treated with IHD. The delivered dialysis dose per session was calculated based on single-pool Kt/V urea. Patients were allocated in two groups according to the weekly delivered median Kt/V: higher intensity dialysis dose (HID: Kt/V higher than median) and lower intensity dialysis dose (LID: Kt/V lower than median). Thereafter, AKI patients were divided according to the presence or absence of sepsis and urine output. Clinical and lab characteristics and survival of AKI patients were compared. Results: A total of 121 AKI patients were evaluated. Forty-two patients did not present with sepsis and 45 did not present with oliguria. Mortality rate after 30 days was lower in the HID group without sepsis (14.3% x 47.6%; p = 0.045) and without oliguria (31.8% x 69.5%; p = 0.025). Survival curves also showed that the HID group had higher survival rate when compared with the LID group in non-septic and non-oliguric patients (p = 0.007 and p = 0.003, respectively). Conclusion: Higher dialysis doses can be associated with better survival of less seriously ill AKI patients.

High volume peritoneal dialysis vs daily hemodialysis: A randomized, controlled trial in patients with acute kidney injury

There is no consensus in the literature on the best renal replacement therapy (RRT) in acute kidney injury (AKI), with both hemodialysis (HD) and peritoneal dialysis (PD) being used as AKI therapy. However, there are concerns about the inadequacy of PD as well as about the intermittency of HD complicated by hemodynamic instability. Recently, continuous replacement renal therapy (CRRT) have become the most commonly used dialysis method for AKI around the world. A prospective randomized controlled trial was performed to compare the effect of high volume peritoneal dialysis (HVPD) with daily hemodialysis (DHD) on AKI patient survival. A total of 120 patients with acute tubular necrosis (ATN) were assigned to HVPD or DHD in a tertiary-care university hospital. The primary end points were hospital survival rate and renal function recovery, with metabolic control as the secondary end point. Sixty patients were treated with HVPD and 60 with DHD. The HVPD and DHD groups were similar for age ( 64.2 +/- 19.8 and 62.5 +/- 21.2 years), gender ( male: 72 and 66%), sepsis ( 42 and 47%), hemodynamic instability ( 61 and 63%), severity of AKI ( Acute Tubular Necrosis-Index Specific Score (ATN-ISS): 0.68 +/- 0.2 and 0.66 +/- 0.2), Acute Physiology, Age, and Chronic Health Evaluation Score (APACHE II) (26.9 +/- 8.9 and 24.1 +/- 8.2), pre-dialysis BUN (116.4 +/- 33.6 and 112.6 +/- 36.8mg per 100 ml), and creatinine ( 5.8 +/- 1.9 and 5.9 +/- 1.4 mg per 100 ml). Weekly delivered Kt/V was 3.6 +/- 0.6 in HVPD and 4.7 +/- 0.6 in DHD ( P<0.01). Metabolic control, mortality rate ( 58 and 53%), and renal function recovery ( 28 and 26%) were similar in both groups, whereas HVPD was associated with a significantly shorter time to the recovery of renal function. In conclusion, HVPD and DHD can be considered as alternative forms of RRT in AKI.

Advances in Peritoneal Dialysis in Acute Kidney Injury

Peritoneal dialysis (PD) is a simple, safe, cheap, and efficient renal replacement therapy method. It can correct metabolic disorders and fluid overload in acute kidney injury (AKI) patients both in and out of the intensive care unit. Use of PD in AKI is enhanced by placement of a Tenckhoff catheter, which can be safely accomplished at the bedside. Some PD modalities, such as high-volume PD and continuous-flow PD, can provide dialysis doses and efficiency comparable to extracorporeal blood purification methods. PD is particularly suitable for neonates, children, and patients with refractory heart failure or who are otherwise hemodynamically unstable. PD should be considered in situations where systemic anticoagulation and/or vascular access are problematic. PD is limited by a lower efficiency that may produce inadequate renal replacement in larger and/or severely hypercatabolic patients. Fluid removal can be unpredictable, there is a risk of infection, and possible issues with mechanical ventilation. In this article, we discuss the use of PD in AKI, with emphasis on recent advances. Copyright (c) 2012 S. Karger AG, Basel

When is dialysis indicated in acute kidney injury?

The indications for dialysis in patients with acute kidney injury (AKI), as well as the dose and timing of initiation, remain uncertain. Recent data have suggested that early initiation of renal replacement therapy (RRT) may be associated with decreased mortality but not with the recovery of kidney function. A blood urea nitrogen (BUN) level of 75 mg/dL is a useful indicator for dialysis in asymptomatic patients, but one that is based on studies with limitations. Different parameters, including absolute and relative indicators, are needed. Currently, nephrologists should consider the trajectory of disease, and the clinical condition and prognosis of the patient are more important than numerical values in the decision to initiate dialysis.

Continuous peritoneal dialysis compared with daily hemodialysis in patients with acute kidney injury

Background: In some parts of the world, peritoneal dialysis is widely used for renal replacement therapy (RRT) in acute kidney injury (AKI), despite concerns about its inadequacy. It has been replaced in recent years by hemodialysis and, most recently, by continuous venovenous therapies. We performed a prospective study to determine the effect of continuous peritoneal dialysis (CPD), as compared with daily hemodialysis (dHD), on survival among patients with AKI.Methods: A total of 120 patients with acute tubular necrosis (ATN) were assigned to receive CPD or dHD in a tertiary-care university hospital. The primary endpoint was hospital survival rate; renal function recovery and metabolic, acid-base, and fluid controls were secondary endpoints.Results: of the 120 patients, 60 were treated with CPD (G1) and 60 with dHD (G2). The two groups were similar at the start of RRT with respect to age (64.2 +/- 19.8 years vs 62.5 +/- 21.2 years), sex (men: 72% vs 66%), sepsis (42% vs 47%), shock (61% vs 63%), severity of AKI [Acute Tubular Necrosis Individual Severity Score (ATNISS): 0.68 +/- 0.2 vs 0.66 +/- 0.22; Acute Physiology and Chronic Health Evaluation (APACHE) II: 26.9 +/- 8.9 vs 24.1 +/- 8.2], pre-dialysis blood urea nitrogen [BUN (116.4 +/- 33.6 mg/dL vs 112.6 +/- 36.8 mg/dL)], and creatinine (5.85 +/- 1.9 mg/dL vs 5.95 +/- 1.4 mg/dL). In G1, weekly delivered Kt/V was 3.59 +/- 0.61, and in G2, it was 4.76 +/- 0.65 (p < 0.01). The two groups were similar in metabolic and acid-base control (after 4 sessions, BUN < 55 mg/dL: 46 +/- 18.7 mg/dL vs 52 +/- 18.2 mg/dL; pH: 7.41 vs 7.38; bicarbonate: 22.8 +/- 8.9 mEq/L vs 22.2 +/- 7.1 mEq/L). Duration of therapy was longer in G2 (5.5 days vs 7.5 days; p = 0.02). Despite the delivery of different dialysis methods and doses, the survival rate did not differ between the groups (58% in G1 vs 52% in G2), and recovery of renal function was similar (28% vs 26%).Conclusion: High doses of CPD provided appropriate metabolic and pH control, with a rate of survival and recovery of renal function similar to that seen with dHD. Therefore, CPD can be considered an alternative to other forms of RRT in AKI.

High-Volume Peritoneal Dialysis in Acute Kidney Injury: Indications and Limitations

Background and objectives Peritoneal dialysis is still used for AKI in developing countries despite concerns about its limitations. The objective of this study was to explore the role of high-volume peritoneal dialysis in AM patients in relation to metabolic and fluid control, outcome, and risk factors associated with death.Design, setting, participants, & measurements A prospective study was performed on 204 AKI patients who were assigned to high-volume peritoneal dialysis (prescribed Kt/V=0.60/session) by flexible catheter and cycler; 150 patients (80.2%) were included in the final analysis.Results Mean age was 63.8 +/- 15.8 years, 70% of patients were in the intensive care unit, and sepsis was the main etiology of AKI (54.7%). BUN and creatinine levels stabilized after four sessions at around 50 and 4 mg/dl, respectively. Fluid removal and nitrogen balance increased progressively and stabilized around 1200 ml and -1 g/d after four sessions, respectively. Weekly delivered Kt/V was 3.5 +/- 0.68. Regarding AKI outcome, 23% of patients presented renal function recovery, 6.6% of patients remained on dialysis after 30 days, and 57.3% of patients died. Age and sepsis were identified as risk factors for death. In urine output, increase of 1 g in nitrogen balance and increase of 500 ml in ultrafiltration after three sessions were identified as protective factors.Conclusions High-volume peritoneal dialysis is effective for a selected AKI patient group, allowing adequate metabolic and fluid control. Age, sepsis, and urine output as well as nitrogen balance and ultrafiltration after three high-volume peritoneal dialysis sessions were associated significantly with death. Clin J Am Soc Nephrol 7: 887-894, 2012. doi: 10.2215/CJN.11131111

Early nephrology consultation can have an impact on outcome of acute kidney injury patients

Background. Patients who develop acute kidney injury (AKI) in the intensive care unit (ICU) have extremely high rates of mortality and morbidity. The objectives of this study were to compare clinical and laboratory characteristics of AKI patients evaluated and not evaluated by nephrologists in ICU and generate the hypothesis of the relationship between timing of nephrology consultation and outcome.Methods. We explored associations among presence and timing of nephrology consultation with ICU stay and in-ICU mortality in 148 ICU patients with AKI at a Brazilian teaching hospital from July 2008 to May 2010. Multivariable logistic regression was used to adjust confounding and selection bias.Results. AKI incidence was 30% and 52% of these AKI patients were evaluated by nephrologists. At multivariable analysis, AKI patients evaluated by nephrologists showed higher Acute Tubular Necrosis-Index Specific Score and creatinine level, more dialysis indications, lower urine output and longer ICU stay. The mortality rate was similar to AKI patients who were not evaluated. Nephrology consultation was delayed (>= 48 h) in 62.3% (median time to consultation, 4.7 days). Lower serum creatinine levels (P - 0.009) and higher urine output (P = 0.002) were associated with delayed consultation. Delayed consultation was associated with increased ICU mortality (65.4 versus 88.2%, P < 0.001).Conclusions. In AKI, patients evaluated by nephrologists seem to be more seriously ill than those not evaluated and present similar mortality rate. The delayed nephrology consultation can be associated with increased ICU mortality.

The effect of 6% Hydroxyethyl starch vs. Ringer's lactate on acute kidney injury after renal ischemia in rats

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Different prescribed doses of high-volume peritoneal dialysis and outcome of patients with acute kidney injury.

The optimal dialysis dose for the treatment of acute kidney injury (AKI) is controversial. No studies have directly examined the effects of peritoneal dialysis (PD) dose on outcomes in AKI. From January 2005 to January 2007, we randomly assigned critically ill patients with AKI to receive higher- or lower-intensity PD therapy (prescribed Kt/Vof 0.8 and 0.5 per session respectively). The main outcome measure was death within 30 days. Of the 61 enrolled patients, 30 were randomly assigned to higher-intensity therapy, and 31, to a lower-intensity PD dose. The two study groups had similar baseline characteristics and received treatment for 6.1 days and 5.7 days respectively (p = 0.42). At 30 days after randomization, 17 deaths had occurred in the higher-intensity group (55%), and 16 deaths, in the lower-intensity group (53%, p = 0.83). There was a significant difference between the groups in the PD dose prescribed compared with the dose delivered (higher-intensity group: 0.8 vs. 0.59, p = 0.04; lower-intensity group: 0.5 vs. 0.49, p = 0.89). The groups had similar metabolic control after 4 PD sessions (blood urea nitrogen: 69.3 +/- 14.4 mg/dL and 60.3 +/- 11.1 mg/dL respectively, p = 0. 71). In critically ill patients with AKI, an intensive PD dose did not lower the mortality or improve the recovery of kidney function or metabolic control. The PD dose is limited by dialysate flow and membrane permeability, and clearance per exchange can decrease if a shorter dwell time is applied.

A randomized clinical trial of high volume peritoneal dialysis versus extended daily hemodialysis for acute kidney injury patients

Background: Acute kidney injury (AKI) requiring dialysis in critically ill patients is associated with an in-hospital mortality rate of 50-80 %. Extended daily hemodialysis (EHD) and high volume peritoneal dialysis (HVPD) have emerged as alternative modalities. Methods: A double-center, randomized, controlled trial was conducted comparing EHD versus HVPD for the treatment for AKI in the intensive care unit (ICU). Four hundred and seven patients were randomized and 143 patients were analyzed. Principal outcome measure was hospital mortality, and secondary end points were recovery of renal function and metabolic and fluid control. Results: There was no difference between the two groups in relation to median ICU stay [11 (5.7-20) vs. 9 (5.7-19)], recovery of kidney function (26.9 vs. 29.6 %, p = 0.11), need for chronic dialysis (9.7 vs. 6.5 %, p = 0.23), and hospital mortality (63.4 vs. 63.9 %, p = 0.94). The groups were different in metabolic and fluid control. Blood urea nitrogen (BUN), creatinine, and bicarbonate levels were stabilized faster in EHD group than in HVPD group. Delivered Kt/V and ultrafiltration were higher in EHD group. Despite randomization, there were significant differences between the groups in some covariates, including age, pre-dialysis BUN, and creatinine levels, biased in favor of the EHD. Using logistic regression to adjust for the imbalances in group assignment, the odds of death associated with HVPD was 1.4 (95 % CI 0.7-2.4, p = 0.19). A detailed investigation of the randomization process failed to explain the marked differences in patient assignment. Conclusions: Despite faster metabolic control and higher dialysis dose and ultrafiltration with EHD, this study provides no evidence of a survival benefit of EHD compared with HVPD. The limitations of this study were that the results were not presented according to the intention to treat and it did not control other supportive management strategies as nutrition support and timing of dialysis initiation that might influence outcomes in AKI. © 2012 Springer Science+Business Media Dordrecht.