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631.
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.  相似文献   
632.

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: NCT00675818  相似文献   
633.

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.  相似文献   
634.
Translocation of bacteria from the intestine causes local and systemic infection in severe acute pancreatitis. Increased intestinal permeability is considered a promoter of bacterial translocation. The mechanism leading to increased gut permeability may involve impaired intestinal capillary blood flow. The aim of this study was to evaluate and correlate early changes in capillary blood flow and permeability of the colon in acute rodent pancreatitis of graded severity. Edematous pancreatitis was induced by intravenous cerulein; necrotizing pancreatitis by intravenous cerulein and intraductal glycodeoxycholic acid. Six hours after induction of pancreatitis, the permeability of the ascending colon was assessed by the Ussing chamber technique; capillary perfusion of the pancreas and colon (mucosal and subserosal) was determined by intravital microscopy. In mild pancreatitis, pancreatic capillary perfusion remained unchanged (2.13 ± 0.06 vs. 1.98 ± 0.04 nl-min−l.cap −1 [control]; P = NS), whereas mucosal (1.59 _± 0.03 vs. 2.28 ± 0.03 nl.min−l.cap −1 [control]; P <0.01) and subserosal (2.47 ± 0.04 vs. 3.74 ± 0.05 nl-min−l.cap -1 [control]; P <0.01) colonic capillary blood flow was significantly reduced. Severe pancreatitis was associated with a marked reduction in both pancreatic (1.06 = 0.03 vs. 1.98 ± 0.04 nl’min-1.cap -1 [control]; P <0.01) and colonic (mucosal: 0.59 = 0.01 vs. 2.28 ± 0.03 nl.min−l.cap -1 [control], P < 0.01; subserosal: 1.96 ± 0.05 vs. 3.74 ± 0.05 nl.min−l.cap -1 [control], P <0.01) capillary perfusion. Colon permeability tended to increase with the severity of the disease (control: 147 ±19 nmol.hr−l.cm {−2}2; mild pancreatitis: 158±23 nmol-hr−l.cm-2; severe pancreatitis: 181 ±33 nmol.hr−l.cm-2; P = NS). Impairment of colonic capillary perfusion correlates with the severity of pancreatitis. A decrease in capillary blood flow in the colon, even in mild pancreatitis not associated with significant protease activation and acinar cell necrosis or impairment of pancreatic capillary perfusion, suggests that colonic microcirculation is especially susceptible to inflammatory injury. There was no significant change in intestinal permeability in the early stage of pancreatitis, suggesting a window of opportunity for therapeutic interventions to prevent the later-observed increase in gut permeability, which could result in improved intestinal microcirculation. Presented at the Thirty-Seventh Annual Meeting of The Society for Surgery of the Alimentary Tract, San Diego, Calif., May 19–22, 1996. Supported in part by Deutsche Forschungsgemeinschaft (DFG Fo 197/3).  相似文献   
635.
A meta‐analysis was performed to assess the effect of surgical site wound infections and risk factors in neonates undergoing surgery. A systematic literature search up to January 2022 incorporated 17 trials involving 645 neonates who underwent surgery at the beginning of the trial; 198 of them had surgical site wound infections, and 447 were control for neonates. The statistical tools like the dichotomous or continuous method used within a random or fixed‐influence model to establish the odds ratio (OR) and mean difference (MD) with 95% confidence intervals (CIs) to evaluate the risk factors and influence of surgical site wound infections in neonates undergoing surgery. Surgical site wound infections had significantly higher mortality with OR value 2.03 at 95% CI 1.40–2.95 with P‐value <0.001, the longer length of hospital stay (MD, 31.88; 95% CI, 18.17–45.59, P < 0.001), and lower birthweight of neonates (MD, −0.30; 95% CI, −0.53 to −0.07, P = 0.01) compared with neonates with no surgical site wound infections undergoing surgery. However, no remarkable change was observed with surgical site wound infections in the gestational age at birth of neonates (MD, −0.70; 95% CI, −1.46 to 0.05, P = 0.07), and the preoperative antibiotic prophylaxis (OR, 1.28; 95% CI, 0.57–2.87, P = 0.55) compared with no surgical site wound infections for neonates undergoing surgery. Surgical site wound infections had significantly higher mortality, a longer length of hospital stay, and lower birthweight of neonates. However, they had no statistically significant difference in the gestational age at birth of neonates and the preoperative antibiotic prophylaxis compared with no surgical site wound infections for neonates undergoing surgery. Furthermore, evidence is needed to confirm the outcomes.  相似文献   
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