Hemofiltration compared to hemodialysis for acute kidney injury: systematic review and meta-analysis

ABSTRACT: INTRODUCTION: The objective of this systematic review and meta-analysis was to determine the effect of renal replacement therapy (RRT), delivered as hemofiltration vs. hemodialysis, on clinical outcomes in patients with acute kidney injury (AKI). METHODS: MEDLINE, EMBASE, and CENTRAL databases and conference abstracts were searched to June 2012 for parallel-group or crossover randomized and quasi-randomized controlled trials (RCTs) evaluating hemofiltration vs. hemodialysis in patients with AKI. Two authors independently selected studies and abstracted data on study quality and outcomes. Additional information was obtained from trial authors. We pooled data using random-effects models. RESULTS: Of 6657 citations, 19 RCTs (10 parallel-group and 9 crossover) met inclusion criteria. Sixteen trials used continuous RRT. Study quality was variable. The primary analysis included 3 parallel-group trials comparing similar doses of hemofiltration and hemodialysis; sensitivity analyses included trials comparing combined hemofiltration-hemodialysis or dissimilar doses. We found no effect of hemofiltration on mortality (risk ratio [RR] 0.96, 95% confidence interval [CI] 0.73-1.25, p=0.76; 3 trials, n=121 [primary analysis]; RR 1.10, 95%CI 0.88-1.38, p=0.38; 8 trials, n=540 [sensitivity analysis]) or other clinical outcomes (RRT dependence in survivors, vasopressor use, organ dysfunction) compared to hemodialysis. Hemofiltration appeared to shorten time to filter failure (mean difference [MD] -7 hours, 95%CI[-19,+5], p=0.24; 2 trials, n=50 [primary analysis]; MD -5 hours, 95%CI[-10, -1], p=0.01; 3 trials, n=113 [including combined hemofiltration-hemodialysis trials comparing similar doses]; MD -6 hours, 95% CI[-10, -1], p=0.02; 5 trials, n=383 [sensitivity analysis]). Data primarily from crossover RCTs suggested that hemofiltration increased clearance of medium to larger molecules, including inflammatory cytokines, compared to hemodialysis, although almost no studies measured changes in serum concentrations. Meta-analyses were based on very limited data. CONCLUSIONS: Data from small RCTs do not suggest beneficial clinical outcomes from hemofiltration, but confidence intervals were wide. Hemofiltration may increase clearance of medium to larger molecules. Larger trials are required to evaluate effects on clinical outcomes.     

Optimal Mode of clearance in critically ill patients with Acute Kidney Injury (OMAKI) - a pilot randomized controlled trial of hemofiltration versus hemodialysis: a Canadian Critical Care Trials Group project

Introduction

Among critically ill patients with acute kidney injury (AKI) needing continuous renal replacement therapy (CRRT), the effect of convective (via continuous venovenous hemofiltration [CVVH]) versus diffusive (via continuous venovenous hemodialysis [CVVHD]) solute clearance on clinical outcomes is unclear. Our objective was to evaluate the feasibility of comparing these two modes in a randomized trial.

Methods

This was a multicenter open-label parallel-group pilot randomized trial of CVVH versus CVVHD. Using concealed allocation, we randomized critically ill adults with AKI and hemodynamic instability to CVVH or CVVHD, with a prescribed small solute clearance of 35 mL/kg/hour in both arms. The primary outcome was trial feasibility, defined by randomization of >25% of eligible patients, delivery of >75% of the prescribed CRRT dose, and follow-up of >95% of patients to 60 days. A secondary analysis using a mixed-effects model examined the impact of therapy on illness severity, defined by sequential organ failure assessment (SOFA) score, over the first week.

Results

We randomized 78 patients (mean age 61.5 years; 39% women; 23% with chronic kidney disease; 82% with sepsis). Baseline SOFA scores (mean 15.9, SD 3.2) were similar between groups. We recruited 55% of eligible patients, delivered >80% of the prescribed dose in each arm, and achieved 100% follow-up. SOFA tended to decline more over the first week in CVVH recipients (-0.8, 95% CI -2.1, +0.5) driven by a reduction in vasopressor requirements. Mortality (54% CVVH; 55% CVVHD) and dialysis dependence in survivors (24% CVVH; 19% CVVHD) at 60 days were similar.

Conclusions

Our results suggest that a large trial comparing CVVH to CVVHD would be feasible. There is a trend toward improved vasopressor requirements among CVVH-treated patients over the first week of treatment.

Trial Registration

ClinicalTrials.gov: {"type":"clinical-trial","attrs":{"text":"NCT00675818","term_id":"NCT00675818"}}NCT00675818     

An efficient record linkage scheme using graphical analysis for identifier error detection

Background  

Integration of information on individuals (record linkage) is a key problem in healthcare delivery, epidemiology, and "business intelligence" applications. It is now common to be required to link very large numbers of records, often containing various combinations of theoretically unique identifiers, such as NHS numbers, which are both incomplete and error-prone.     

Early diagnosis of nonviable pregnancy with endovaginal US

The mean diameter of the gestation sac and the presence or absence of a yolk sac or embryo and/or cardiac pulsations on endovaginal ultrasound (US) images were correlated with normal and abnormal outcomes of pregnancy. Sixty-two patients who were less than 10 weeks pregnant (menstrual age) underwent endovaginal US. In 59 patients with gestation sacs greater than or equal to 8 mm, the absence of a yolk sac predicted a nonviable pregnancy with a sensitivity of 67% and a specificity of 100%. In 35 patients with gestation sacs greater than or equal to 16 mm, the absence of an embryo predicted a nonviable pregnancy with a sensitivity of 50% and a specificity of 100%. When the absence of cardiac pulsations was added to the latter group of patients, the sensitivity was 100% and the specificity was 100%. The combination of these criteria (gestation sac size; demonstration of yolk sac, embryo and/or cardiac pulsations) enabled the early (less than 10 weeks menstrual age) diagnosis of a nonviable pregnancy with endovaginal US.     

Stimulation of proliferation of human myeloid leukemia cells in culture: applications for cytogenetic analysis

The use of chromosome banding techniques has provided a valuable diagnostic tool in various malignancies. The application of these methods, however, is often restricted by a low yield of mitotic cells and the patient's unwillingness to comply with repeated bone marrow aspiration. In an attempt to promote mitotic activity of leukemic cells from the bone marrow and peripheral blood, we employed a new method based on culturing the cells in the presence of a conditioned medium derived from a human bladder carcinoma cell line (5637). In addition to colony stimulating factor, this conditioned medium contains a factor that is capable of stimulating leukemic myeloblast proliferation. Bone marrow and peripheral blood mononuclear cells from 58 patients with a variety of myeloid leukemias were cultured for 24 to 120 hours in the presence or absence of conditioned medium. These bone marrow cells showed a pronounced increase in the mitotic index (5- to 50-fold) as compared to unstimulated cultures, and a greater than 100-fold increase as compared to fresh, uncultured bone marrow cells. Analyzable metaphases could be obtained even in marrow samples in which direct or 24-hour G-banding techniques had failed to reveal metaphases. The effect observed on peripheral blood cells was even more dramatic because prior to culture no mitotic cells were detected, whereas up to 2% mitotic cells were found in conditioned medium-stimulated peripheral leukemic cells. Karyotype analysis of 36 out of the 58 leukemic patients has shown that the chromosome changes discovered in conditioned medium stimulated cells were identical to those found in unstimulated cells. New chromosome aberrations, attributable to the stimulation of growth by conditioned medium, were not found. The quality of the metaphases analyzed following conditioned medium stimulation was considerably better than that of unstimulated samples. Frozen cells, when cultured with conditioned medium, were also suitable for cytogenetic analysis. Thus, the use of this conditioned medium permits adequate cytogenetic analysis even in cases where such analysis was previously impossible.     

Conquering the complex world of human septins: implications for health and disease

Peterson EA and Petty EM. Conquering the complex world of human septins: implications for health and disease. Septins are highly conserved filamentous proteins first characterized in budding yeast and subsequently identified in must eukaryotes. Septins can bind and hydrolyze GTP, which is intrinsically related to their formation of septin hexamers and functional protein interactions. The human septin family is composed of 14 loci, SEPT1‐SEPT14, which encode dozens of different septin proteins. Their central GTPase and polybasic domain regions are highly conserved but they diverge in their N‐terminus and/or C‐terminus. The mechanism by which the different isoforms are generated is not yet well understood, but one can hypothesize that the use of different promoters and/or alternative splicing could give rise to these variants. Septins perform diverse cellular functions according to tissue expression and their interacting partners. Functions identified to date include cell division, chromosome segregation, protein scaffolding, cellular polarity, motility, membrane dynamics, vesicle trafficking, exocytosis, apoptosis, and DNA damage response. Their expression is tightly regulated to maintain proper filament assembly and normal cellular functions. Alterations of these proteins, by mutation or expression changes, have been associated with a variety of cancers and neurological diseases. The association of septins with cancer results from alterations of expression in solid tumors or translocations in leukemias [mixed lineage leukemia (MLL)]. Expression changes in septins have also been associated with neurological conditions such as Alzheimer's and Parkinson's disease, as well as retinopathies, hepatitis C, spermatogenesis and Listeria infection. Pathogenic mutations of SEPT9 were identified in the autosomal dominant neurological disorder hereditary neuralgic amyotrophy (HNA). Human septin research over the past decade has established their importance in cell biology and human disease. Further functional characterization of septins is crucial to our understanding of their possible diagnostic, prognostic, and therapeutic applications.     

Aphasia Bill of Rights

The author, who has lived with aphasia for more than 30 years, offers a personal perspective on the “Aphasia Bill of Rights,” adopted by the National Aphasia Association Board of Directors.     

The spectrum of paediatric dermatoses in a university hospital in Cairo,Egypt

Background Epidemiological data on paediatric dermatoses in Egypt are scanty. Objective To study the spectrum of paediatric dermatoses in Cairo. Methods The medical records of children attending the dermatology outpatient clinics of Ain Shams University hospital for the year 2001 were retrieved. Data of 3049 patients were included. Demographic data (age and gender) and diagnoses were extracted, coded and analysed. Results Patients’ attendance peaked in summer (42.57%) and revealed female predominance (1.3 : 1). Infections constituted most of dermatoses (52.87%) and impetigo was most common (12.04%). Hypersensitivity came after (18.6%), and contact dermatitis prevailed (6.03%). Females predominated in most dermatoses. Bacterial infections were the most common in both genders. Age distribution revealed prevalence of bacterial infections in infants and preschool children, parasitic infections in school children and sebaceous gland disorders in adolescents. Parasitic infections prevailed in winter and spring, whereas bacterial infections prevailed in summer and autumn. Most dermatoses peaked in summer except urticaria and chicken pox that peaked in spring. Conclusion Infections outnumbered other paediatric dermatoses parallel to the situation in developing communities. Such diseases are potentially controllable and therefore strategies that target infections may represent a key to an efficient child health care programme.     

Timing of Adjuvant Fractionated Stereotactic Radiosurgery Affects Local Control of Resected Brain Metastases

PurposeFor resected brain metastases (BMs), stereotactic radiosurgery (SRS) is often offered to minimize local recurrence (LR). Although the aim is to deliver SRS within a few weeks of surgery, a variety of socioeconomic, medical, and procedural issues can cause delays. We evaluated the relationship between timing of postoperative SRS and LR.Methods and MaterialsWe retrospectively identified a consecutive series of patients with BM managed with resection and SRS or fractionated SRS at our institution from 2012 to 2018. We assessed the correlation of time to SRS and other demographic, disease, and treatment variables with LR, local recurrence-free survival, distant recurrence, distant recurrence-free survival, and overall survival.ResultsA total of 133 patients met inclusion criteria. The median age was 64.5 years. Approximately half of patients had a single BM, and median BM size was 2.9 cm. Gross total resection was achieved in 111 patients (83.5%), and more than 90% of patients received fractionated SRS. The median time to SRS was 37.0 days, and the LR rate was 16.4%. Time to SRS was predictive of LR. The median time from surgery to SRS was 34.0 days for patients without LR versus 61.0 days for those with LR (P < .01). The LR rate was 2.3% with SRS administered ≤4 weeks postoperatively, compared with 23.6% if SRS was administered >4 weeks postoperatively (P < .01). Local recurrence-free survival was also improved for patients who underwent SRS at ≤4 weeks (P = .02). Delayed SRS was also predictive of distant recurrence (P = .02) but not overall survival.ConclusionsIn this retrospective study, the strongest predictor of LR after postoperative SRS for BM was time to SRS, and a cutoff of 4 weeks was a reliable predictor of recurrence. These findings merit investigation in a prospective, randomized trial.