Tranexamic Acid in Patients Undergoing Noncardiac Surgery.

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.).

Rationale and design of the PeriOperative ISchemic Evaluation-3 (POISE-3): a randomized controlled trial evaluating tranexamic acid and a strategy to minimize hypotension in noncardiac surgery.

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.

Effect of a Perioperative Hypotension-Avoidance Strategy Versus a Hypertension-Avoidance Strategy on the Risk of Acute Kidney Injury: A Clinical Research Protocol for a Substudy of the POISE-3 Randomized Clinical Trial.

BACKGROUND: Most patients who take antihypertensive medications continue taking them on the morning of surgery and during the perioperative period. However, growing evidence suggests this practice may contribute to perioperative hypotension and a higher risk of complications. This protocol describes an acute kidney injury substudy of the Perioperative Ischemic Evaluation-3 (POISE-3) trial, which is testing the effect of a perioperative hypotension-avoidance strategy versus a hypertension-avoidance strategy in patients undergoing noncardiac surgery. OBJECTIVE: To conduct a substudy of POISE-3 to determine whether a perioperative hypotension-avoidance strategy reduces the risk of acute kidney injury compared with a hypertension-avoidance strategy. DESIGN: Randomized clinical trial with 1:1 randomization to the intervention (a perioperative hypotension-avoidance strategy) or control (a hypertension-avoidance strategy). INTERVENTION: If the presurgery systolic blood pressure (SBP) is <130 mmHg, all antihypertensive medications are withheld on the morning of surgery. If the SBP is ≥130 mmHg, some medications (but not angiotensin receptor blockers [ACEIs], angiotensin receptor blockers [ARBs], or renin inhibitors) may be continued in a stepwise manner. During surgery, the patients' mean arterial pressure (MAP) is maintained at ≥80 mmHg. During the first 48 hours after surgery, some antihypertensive medications (but not ACEIs, ARBs, or renin inhibitors) may be restarted in a stepwise manner if the SBP is ≥130 mmHg. CONTROL: Patients receive their usual antihypertensive medications before and after surgery. The patients' MAP is maintained at ≥60 mmHg from anesthetic induction until the end of surgery. SETTING: Recruitment from 108 centers in 22 countries from 2018 to 2021. PATIENTS: Patients (~6800) aged ≥45 years having noncardiac surgery who have or are at risk of atherosclerotic disease and who routinely take antihypertensive medications. MEASUREMENTS: The primary outcome of the substudy is postoperative acute kidney injury, defined as an increase in serum creatinine concentration of either ≥26.5 µmol/L (≥0.3 mg/dL) within 48 hours of randomization or ≥50% within 7 days of randomization. METHODS: The primary analysis (intention-to-treat) will examine the relative risk and 95% confidence interval of acute kidney injury in the intervention versus control group. We will repeat the primary analysis using alternative definitions of acute kidney injury and examine effect modification by preexisting chronic kidney disease, defined as a prerandomization estimated glomerular filtration rate <60 mL/min/1.73 m2. RESULTS: Substudy results will be analyzed in 2022. LIMITATIONS: It is not possible to mask patients or providers to the intervention; however, objective measures will be used to assess acute kidney injury. CONCLUSIONS: This substudy will provide generalizable estimates of the effect of a perioperative hypotension-avoidance strategy on the risk of acute kidney injury.

CONTEXTE: La plupart des patients qui prennent des médicaments antihypertenseurs continuent de les prendre le matin d'une intervention chirurgicale et pendant la période périopératoire. De plus en plus de preuves suggèrent que cette pratique pourrait entraîner l'hypotension périopératoire et augmenter le risque de complications. Ce protocole décrit une sous-étude sur l'insuffisance rénale aiguë (IRA) découlant de l'essai Perioperative Ischemic Evaluation-3 (POISE-3). Cet essai teste l'effet d'une stratégie d'évitement de l'hypotension périopératoire par rapport à une stratégie d'évitement de l'hypertension chez des patients qui subissent une chirurgie non cardiaque. OBJECTIFS: Cette sous-étude de l'essai POISE-3 vise à déterminer si une stratégie d'évitement de l'hypotension périopératoire réduit le risque d'IRA comparativement à la stratégie d'évitement de l'hypertension. TYPE D'ÉTUDE: Essai clinique randomisé à répartition 1:1 au groupe intervention (stratégie d'évitement de l'hypotension périopératoire) ou au groupe témoin (stratégie d'évitement de l'hypertension). GROUPE INTERVENTION: Si la pression artérielle systolique (PAS) avant l'opération est <130 mmHg, tous les médicaments antihypertenseurs sont suspendus le matin de la chirurgie. Si la PAS est ≥130 mmHg, certains médicaments (excluant les inhibiteurs de l'enzyme de conversion de l'angiotensine [IECA], les antagonistes du récepteur de l'angiotensine [ARA] ou les inhibiteurs de la rénine) peuvent être poursuivis de façon graduelle. Pendant la chirurgie, la pression artérielle moyenne (PAM) du patient est maintenue à ≥80 mmHg. Dans les 48 heures suivant l'intervention chirurgicale, certains médicaments antihypertenseurs (excluant les IECA, les ARA ou les inhibiteurs de la rénine) peuvent être réintroduits par étapes si la PAS est ≥130 mmHg. GROUPE TÉMOIN: Les patients reçoivent leurs médicaments antihypertenseurs habituels avant et après la chirurgie. La PAM du patient est maintenue à ≥60 mmHg de l'induction de l'anesthésie à la fin de l'intervention chirurgicale. CADRE: Recrutement à partir de 108 centres dans 22 pays entre 2018 à 2021. SUJETS: Des patients (~6 800) âgés de 45 ans et plus atteints d'athérosclérose, ou présentant un risque de l'être, devant subir une chirurgie non cardiaque et prenant des médicaments antihypertenseurs sur une base régulière. MESURES: Le principal critère d'évaluation de cette sous-étude est une IRA postopératoire définie par une hausse d'au moins 26,5 µmol/L (≥0,3 mg/dL) de la créatinine sérique dans les 48 heures suivant la randomisation ou d'au moins 50 % dans les 7 jours suivant la randomisation. MÉTHODOLOGIE: L'analyse primaire (par intention de traiter) examinera le risque relatif d'une IRA et l'intervalle de confiance à 95 % dans le groupe intervention par rapport au groupe témoin. Nous répéterons l'analyse primaire en utilisant d'autres définitions de l'IRA et nous examinerons la modification de l'effet en présence d'une insuffisance rénale préexistante (définie par un DFGe prérandomisation <60 ml/min/1,73 m2). RÉSULTATS: Les résultats de cette sous-étude seront analysés en 2022. LIMITES: Il n'est pas possible de procéder à l'insu des patients ou des prestataires de soins pour cette intervention; des mesures objectives seront toutefois utilisées pour évaluer l'IRA. CONCLUSION: Cette sous-étude fournira des estimations généralisables de l'effet d'une stratégie visant à éviter l'hypotension périopératoire sur le risque d'insuffisance rénale aiguë.