More-intensive renal replacement therapy has no benefit in critically ill patients with acute kidney injury

Comparison of hemodynamic instability among continuous, intermittent and hybrid renal replacement therapy in acute kidney injury: A systematic review of randomized clinical trials

PURPOSE

To compare hemodynamic instability during continuous, intermittent and hybrid renal replacement therapy (RRT) in critically ill patients, and its association with renal recovery and mortality.

MATERIALS AND METHODS

The search was conducted in accordance with the PRISMA guidelines which was registered at the PROSPERO Database (CRD42018086504). Randomized clinical trials (RCTs) involving critically ill patients with acute kidney injury (AKI) treated with continuous, intermittent or hybrid RRT were included. The search was performed using PubMed, Embase and Cochrane databases.

RESULTS

Out of 3442 citations retrieved, 12 RCTs were included in the systematic analysis, representing 1419 patients. Most studies (n = 8) did not report differences in hemodynamic parameters across different RTT modalities. The incidence of hypotensive episodes varied from 5 to 60% among the studies. Punctual differences on heart rate and blood pressure were observed among studies. However, studies presented high heterogeneity in terms of outcome definitions and measurement, thus making the conduction of meta-analysis impossible.

CONCLUSIONS

There is very few information available regarding hemodynamic tolerance of renal replacement therapy methods. A better standardization of hemodynamic tolerance and further reports are needed before conclusions can be drawn.

Comparison of sustained hemodiafiltration with acetate-free dialysate and continuous venovenous hemodiafiltration for the treatment of critically ill patients with acute kidney injury

We conducted a prospective, randomized study to compare conventional continuous venovenous hemodiafiltration (CVVHDF) with sustained hemodiafiltration (SHDF) using an acetate-free dialysate. Fifty critically ill patients with acute kidney injury (AKI) who required renal replacement therapy were treated with either CVVHDF or SHDF. CVVDHF was performed using a conventional dialysate with an effluent rate of 25 mL·kg⁻¹ · ^h−1, and SHDF was performed using an acetate-free dialysate with a flow rate of 300−500 mL/min. The primary study outcome, 30 d survival rate was 76.0% in the CVVHDF arm and 88.0% in the SHDF arm (NS). Both the number of patients who showed renal recovery (40.0% and 68.0%, CVVHDF and SHDF, resp.; P < .05), and the hospital stay length (42.3 days and 33.7 days, CVVHDF and SHDF, resp.; P < .05), significantly differed between the two treatments. Although the total convective volumes did not significantly differ, the dialysate flow rate was higher and mean duration of daily treatment was shorter in the SHDF treatment arm. Our results suggest that compared with conventional CVVHDF, more intensive renal support in the form of post-dilution SHDF with acetate-free dialysate may accelerate renal recovery in critically ill patients with AKI.

Comparison of sustained hemodiafiltration with continuous venovenous hemodiafiltration for the treatment of critically ill patients with acute kidney injury

Despite improvements in medical care, the mortality of critically ill patients with acute kidney injury (AKI) who require renal replacement therapy (RRT) remains high. We describe a new approach, sustained hemodiafiltration, to treat patients who suffered from acute kidney injury and were admitted to intensive care units (ICUs). In our study, 60 critically ill patients with AKI who required RRT were treated with either continuous venovenous hemodiafiltration (CVVHDF) or sustained hemodiafiltration (S-HDF). The former was performed by administering a postfilter replacement fluid at an effluent rate of 35 mL/kg/h, and the latter was performed by administering a postfilter replacement fluid at a dialysate-flow rate of 300-500 mL/min. The S-HDF was delivered on a daily basis. The baseline characteristics of the patients in the two treatment groups were similar. The primary study outcome--survival until discharge from the ICU or survival for 30 days, whichever was earlier--did not significantly differ between the two groups: 70% after CVVHDF and 87% after S-HDF. The hospital-survival rate after CVVHDF was 63% and that after S-HDF was 83% (P < 0.05). The number of patients who showed renal recovery at the time of discharge from the ICU and the hospital and the duration of the ICU stay significantly differed between the two treatments (P < 0.05). Although there was no significant difference between the mean number of treatments performed per patient, the mean duration of daily treatment in the S-HDF group was 6.5 +/- 1.0 h, which was significantly shorter. Although the total convective volumes--the sum of the replacement-fluid and fluid-removal volumes--did not differ significantly, the dialysate-flow rate was higher in the S-HDF group. Our results suggest that in comparison with conventional continuous RRT, including high-dose CVVHDF, more intensive renal support in the form of postdilution S-HDF will decrease the mortality and accelerate renal recovery in critically ill patients with AKI.

[Cardiorenal syndrome]

With increasing age of a population, the rate and severity of comorbidities are also growing, resulting in a rising number of people with a condition described as "cardiorenal syndrome". Initially, cardiorenal syndrome defined the decline in cardiac and renal function due to diminished renal perfusion in the context of heart failure. However, in order to give consideration to the numerous comorbidities, nowadays the definition has been widened. Following a new classification, five types of cardiorenal syndrome are distinguished. Such a differentiation is helpful to find the appropriate therapeutic approach, according to the underlying disease. Therefore, the new classification and modern therapeutic concepts shall be presented here.