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In this pre-specified sub-study of the POISE-3 trial, we examined the effect of a perioperative hypotension-avoidance strategy versus a hypertension-avoidance strategy on the risk of postoperative acute kidney injury (AKI). Altogether, 7307 patients were included from 110 hospitals in 22 countries. Patients were 45 years and older, had or were at risk of atherosclerotic disease, took at least one antihypertensive medication, and were scheduled for noncardiac surgery. Hypotension-avoidance strategy: (i) target intraoperative mean arterial pressure (MAP) 80 mm Hg or over, (ii) on day of surgery and for two days after, hold renin-angiotensin-aldosterone system inhibitors and use other antihypertensives in stepwise fashion if systolic blood pressure (SBP) 130 mm Hg or more. Hypertension-avoidance strategy: (i) target intraoperative MAP 60 mm Hg or more, (ii) continue all antihypertensives before and after surgery. Primary outcome: postoperative AKI, an increase in serum creatinine concentration of either 26.5 μmol/L or more (0.3 mg/dL or more) within 48 hours of randomization or 50% or more within seven days of randomization. The hypotension-avoidance group (3654 patients) used fewer antihypertensive medications than the hypertension-avoidance group (3653 patients); specifically, 6% vs. 38% used an ACEI or ARB on the day of surgery, and 6% vs. 47% and 7% vs. 50% one and two days after surgery, respectively. Patients also spent about half as much intraoperative time with a MAP under 80 mm Hg (27 vs. 60 minutes, respectively), but had little difference in average BP before or after surgery. There was no significant difference in AKI risk (15.1% vs. 14.4%). Results were consistent with other definitions of AKI and in patients with preexisting chronic kidney disease. Thus, a hypotension-avoidance strategy targeting a MAP greater than 80 mm Hg in the operating room and discontinued blood pressure medication during the perioperative period did not confer a lower risk of AKI compared to a hypertension avoidance strategy.

Major bleeding in noncardiac surgery is common and associated with serious complications. The antifibrinolytic agent tranexamic acid (TXA) reduces bleeding and may reduce the risk of these complications. TXA also may have immunomodulatory effects that could reduce surgical site infection. Clinical trials of TXA in noncardiac surgery have been insufficiently powered to evaluate its efficacy and safety. Therefore, large randomised controlled trials of its use in noncardiac surgery are required. To ensure that future clinical trials are feasible and acceptable, we undertook a survey of Fellows of the Australian and New Zealand College of Anaesthetists (ANZCA). Our aims were to ascertain current patterns of TXA administration and to assess the acceptability of randomising patients to intravenous TXA or placebo. A 12-item survey was electronically mailed to 1001 ANZCA Fellows. Two hundred and eighty nine responses were received and analysed (response rate 29%). Ninety-eight percent of respondents had used intravenous TXA in noncardiac surgery; 67% give TXA routinely for lower limb arthroplasty, with smaller proportions giving TXA for spinal surgery (40%) and other major orthopaedic surgery (28%). Almost half (49%) give TXA routinely for major trauma surgery. Thirty-six percent indicated that they did not give TXA for major vascular, abdominal, pelvic or thoracic surgery. The majority administered TXA as a single, fixed dose. Fifty-seven percent agreed that there is uncertainty about the relative risks and benefits of perioperative TXA in noncardiac surgery and 87% agreed that large definitive trials determining the safety and efficacy of perioperative TXA in noncardiac surgery are required. These results indicate that for ANZCA Fellows the use of TXA in noncardiac surgery is highly variable, that there is uncertainty about the safety and efficacy of TXA, and that a large trial would be acceptable.