RESUMO
BACKGROUND: Perioperative bleeding is common in patients undergoing noncardiac surgery. Tranexamic acid is an antifibrinolytic drug that may safely decrease such bleeding. METHODS: We conducted a trial involving patients undergoing noncardiac surgery. Patients were randomly assigned to receive tranexamic acid (1-g intravenous bolus) or placebo at the start and end of surgery (reported here) and, with the use of a partial factorial design, a hypotension-avoidance or hypertension-avoidance strategy (not reported here). The primary efficacy outcome was life-threatening bleeding, major bleeding, or bleeding into a critical organ (composite bleeding outcome) at 30 days. The primary safety outcome was myocardial injury after noncardiac surgery, nonhemorrhagic stroke, peripheral arterial thrombosis, or symptomatic proximal venous thromboembolism (composite cardiovascular outcome) at 30 days. To establish the noninferiority of tranexamic acid to placebo for the composite cardiovascular outcome, the upper boundary of the one-sided 97.5% confidence interval for the hazard ratio had to be below 1.125, and the one-sided P value had to be less than 0.025. RESULTS: A total of 9535 patients underwent randomization. A composite bleeding outcome event occurred in 433 of 4757 patients (9.1%) in the tranexamic acid group and in 561 of 4778 patients (11.7%) in the placebo group (hazard ratio, 0.76; 95% confidence interval [CI], 0.67 to 0.87; absolute difference, -2.6 percentage points; 95% CI, -3.8 to -1.4; two-sided P<0.001 for superiority). A composite cardiovascular outcome event occurred in 649 of 4581 patients (14.2%) in the tranexamic acid group and in 639 of 4601 patients (13.9%) in the placebo group (hazard ratio, 1.02; 95% CI, 0.92 to 1.14; upper boundary of the one-sided 97.5% CI, 1.14; absolute difference, 0.3 percentage points; 95% CI, -1.1 to 1.7; one-sided P = 0.04 for noninferiority). CONCLUSIONS: Among patients undergoing noncardiac surgery, the incidence of the composite bleeding outcome was significantly lower with tranexamic acid than with placebo. Although the between-group difference in the composite cardiovascular outcome was small, the noninferiority of tranexamic acid was not established. (Funded by the Canadian Institutes of Health Research and others; POISE-3 ClinicalTrials.gov number, NCT03505723.).
Assuntos
Antifibrinolíticos , Ácido Tranexâmico , Antifibrinolíticos/efeitos adversos , Antifibrinolíticos/uso terapêutico , Canadá , Hemorragia/etiologia , Hemorragia/prevenção & controle , Humanos , Procedimentos Cirúrgicos Operatórios , Trombose/induzido quimicamente , Trombose/tratamento farmacológico , Ácido Tranexâmico/efeitos adversos , Ácido Tranexâmico/uso terapêuticoRESUMO
BACKGROUND: For patients undergoing noncardiac surgery, bleeding and hypotension are frequent and associated with increased mortality and cardiovascular complications. Tranexamic acid (TXA) is an antifibrinolytic agent with the potential to reduce surgical bleeding; however, there is uncertainty about its efficacy and safety in noncardiac surgery. Although usual perioperative care is commonly consistent with a hypertension-avoidance strategy (i.e., most patients continue their antihypertensive medications throughout the perioperative period and intraoperative mean arterial pressures of 60 mmHg are commonly accepted), a hypotension-avoidance strategy may improve perioperative outcomes. METHODS: The PeriOperative Ischemic Evaluation (POISE)-3 Trial is a large international randomized controlled trial designed to determine if TXA is superior to placebo for the composite outcome of life-threatening, major, and critical organ bleeding, and non-inferior to placebo for the occurrence of major arterial and venous thrombotic events, at 30 days after randomization. Using a partial factorial design, POISE-3 will additionally determine the effect of a hypotension-avoidance strategy versus a hypertension-avoidance strategy on the risk of major cardiovascular events, at 30 days after randomization. The target sample size is 10,000 participants. Patients ≥45 years of age undergoing noncardiac surgery, with or at risk of cardiovascular and bleeding complications, are randomized to receive a TXA 1 g intravenous bolus or matching placebo at the start and at the end of surgery. Patients, health care providers, data collectors, outcome adjudicators, and investigators are blinded to the treatment allocation. Patients on ≥ 1 chronic antihypertensive medication are also randomized to either of the two blood pressure management strategies, which differ in the management of patient antihypertensive medications on the morning of surgery and on the first 2 days after surgery, and in the target mean arterial pressure during surgery. Outcome adjudicators are blinded to the blood pressure treatment allocation. Patients are followed up at 30 days and 1 year after randomization. DISCUSSION: Bleeding and hypotension in noncardiac surgery are common and have a substantial impact on patient prognosis. The POISE-3 trial will evaluate two interventions to determine their impact on bleeding, cardiovascular complications, and mortality. TRIAL REGISTRATION: ClinicalTrials.gov NCT03505723. Registered on 23 April 2018.
Assuntos
Antifibrinolíticos , Hipotensão , Ácido Tranexâmico , Antifibrinolíticos/efeitos adversos , Perda Sanguínea Cirúrgica/prevenção & controle , Humanos , Hipotensão/induzido quimicamente , Hipotensão/diagnóstico , Hipotensão/prevenção & controle , Assistência Perioperatória , Ácido Tranexâmico/efeitos adversosRESUMO
OBJECTIVE: There is increasing evidence to suggest that ossein-hydroxyapatite complex (OHC) is more effective than calcium supplements in maintaining bone mass. The aim of this meta-analysis was to determine whether OHC has a different clinical effect on bone mineral density (BMD) compared with calcium carbonate (CC). METHODS: A meta-analysis of randomized controlled clinical trials was carried out to evaluate the efficacy of OHC versus CC on trabecular BMD. We identified publications on clinical trials by a search of electronic databases, including MEDLINE (1966-November 2008), EMBASE (1974-November 2008), and the Cochrane Controlled Clinical Trials Register.The primary endpoint was percent change in BMD from baseline. Data were pooled in a random-effects model, and the weighted mean difference was calculated. A sensitivity analysis that excluded trials without full data was performed. RESULTS: Of the 18 controlled trials initially identified, 6 were included in the meta-analysis. There was no significant heterogeneity among the included trials. The percent change in BMD significantly favored the OHC group (1.02% [95% CI, 0.63-1.41], P < 0.00001). These results were confirmed in the sensitivity analysis. CONCLUSIONS: OHC is significantly more effective in preventing bone loss than CC.