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641.
Francisco Leyva Paul WX Foley Shajil Chalil Karim Ratib Russell EA Smith Frits Prinzen Angelo Auricchio 《Journal of cardiovascular magnetic resonance》2011,13(1):29
Background
Myocardial scarring at the LV pacing site leads to incomplete resynchronization and a suboptimal symptomatic response to CRT. We sought to determine whether the use of late gadolinium cardiovascular magnetic resonance (LGE-CMR) to guide left ventricular (LV) lead deployment influences the long-term outcome of cardiac resynchronization therapy (CRT).Methods
559 patients with heart failure (age 70.4 ± 10.7 yrs [mean ± SD]) due to ischemic or non-ischemic cardiomyopathy underwent CRT. Implantations were either guided (+CMR) or not guided (-CMR) by LGE-CMR prior to implantation. Fluoroscopy and LGE-CMR were used to localize the LV lead tip and and myocardial scarring retrospectively. Clinical events were assessed in three groups: +CMR and pacing scar (+CMR+S); CMR and not pacing scar (+CMR-S), and; LV pacing not guided by CMR (-CMR).Results
Over a maximum follow-up of 9.1 yrs, +CMR+S had the highest risk of cardiovascular death (HR: 6.34), cardiovascular death or hospitalizations for heart failure (HR: 5.57) and death from any cause or hospitalizations for major adverse cardiovascular events (HR: 4.74) (all P < 0.0001), compared with +CMR-S. An intermediate risk of meeting these endpoints was observed for -CMR, with HRs of 1.51 (P = 0.0726), 1.61 (P = 0.0169) and 1.87 (p = 0.0005), respectively. The +CMR+S group had the highest risk of death from pump failure (HR: 5.40, p < 0.0001) and sudden cardiac death (HR: 4.40, p = 0.0218), in relation to the +CMR-S group.Conclusions
Compared with a conventional implantation approach, the use of LGE-CMR to guide LV lead deployment away from scarred myocardium results in a better clinical outcome after CRT. Pacing scarred myocardium was associated with the worst outcome, in terms of both pump failure and sudden cardiac death. 相似文献642.
643.
Hemofiltration compared to hemodialysis for acute kidney injury: systematic review and meta-analysis
JO Friedrich R Wald SM Bagshaw KE Burns NK Adhikari 《Critical care (London, England)》2012,16(4):R146-16
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
644.
Ron Wald Jan O Friedrich Sean M Bagshaw Karen EA Burns Amit X Garg Michelle A Hladunewich Andrew A House Stephen Lapinsky David Klein Neesh I Pannu Karen Pope Robert M Richardson Kevin Thorpe Neill KJ Adhikari 《Critical care (London, England)》2012,16(5):R205
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645.
John M Finney A Sarah Walker Tim EA Peto David H Wyllie 《BMC medical informatics and decision making》2011,11(1):7
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646.
Bethune C Seierstad SL Seljeflot I Johansen O Arnesen H Meltzer HM Rosenlund G Frøyland L Lundebye AK 《European journal of clinical investigation》2006,36(3):193-201
BACKGROUND: In a previous study, a group of coronary heart disease (CHD) patients exhibited positive cardioprotective effects of fatty acids derived from a diet of farmed Atlantic salmon fed fish oil (Seierstad et al. 2005). This follow-up study examines these patients for plasma exposure to selected organic and inorganic contaminants found in seafood that may detract from the benefits of eating oily fish. METHODS: The study design was from Seierstad et al. (2005), where 58 patients were allocated into three groups consuming 700 g week(-1) of differently fed Atlantic salmon (Salmo salar) fillets for 6 weeks: 100% fish oil (FO), 100% rapeseed oil (RO), or 50% of each (FO/RO). RESULTS: Different fillets showed graded levels (FO > FO/RO > RO) of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), dioxin-like polychlorinated biphenyls (DLPCBs), indicator PCBs, polybrominated diphenyl ethers (PBDEs), and arsenic (As). Mercury (Hg) and lead (Pb) levels were similar across the three types of fillets. After 6 weeks of consumption, patient levels of PCDDs, DLPCBs, and PCBs in plasma decreased as the dietary intake of these contaminants increased. Plasma PBDEs only showed increases for the FO patients. Levels of inorganic contaminants in plasma showed only slight changes over the study period. CONCLUSIONS: These results show a reduction in the use of marine oils in fish feed reduces organic contaminant levels in farmed salmon while still providing a good dietary source of marine fatty acids. 相似文献
647.
Intestinal microcirculation and gut permeability in acute pancreatitis: Early changes and therapeutic implications 总被引:11,自引:1,他引:11
Dr. Hubert G. Hotz M.D. Thomas Foitzik M.D. Janine Rohweder M.D. Joerg D. Schulzke M.D. Micbael Fromm M.D. Norbert S. F. Runkel M.D. Heinz J. Bubr M.D. EA.C.S. 《Journal of gastrointestinal surgery》1998,2(6):518-525
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
648.
Mohamed A. Abdelgawad Della G.T. Parambi Mohammed M. Ghoneim Nasser Hadal Alotaibi Abdulaziz Ibrahim Alzarea Abdullah S. Alanazi Ahmed Hassan Sara M. Tony Mohamed EA Abdelrahim 《International wound journal》2022,19(8):2092
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