Hypotension-Avoidance No Better than Hypertension-Avoidance for Reducing Post-Op Adverse Events

PJ Devereaux, MD, PhD
Credit: Population Health Research Institute

New data indicates hypotensive avoidance strategies may not be the most effective method for staving off postoperative adverse events, according to a 7000-person study.

Results of the study, which compared hypotension-avoidance strategies against hypertension-avoidance strategies for postoperative hypotension, indicate a hypotension-avoidance strategy did not result in a reduction in postoperative adverse and vascular events.

“In patients having noncardiac surgery and receiving long-term antihypertensive therapy, POISE-3 showed no difference in effects on major vascular complications between 2 alternative blood pressure management strategies,” investigators wrote.¹

Led by PJ Devereaux, MD, PhD, and other investigators from the Population Health Research Institute, the POISE-3 study was launched with the intent of investigating whether intraoperative tranexamic acid might reduce risk of bleeding relative to placebo and to compare perioperative hypotension-avoidance strategy versus hypertension-avoidance strategy on major adverse complications in a cohort of patients undergoing non cardiac surgery considered to be at risk of vascular events. Designed as a partial factorial randomized trial, patients were randomized 9535 patients to tranexamic acid or placebo and 7490 patients to a hypotension-avoidance strategy or a hypertension-avoidance strategy.¹

Data from POISE-3 related to the effects of intraoperative tranexamic acid were presented at the American College of Cardiology 2022 annual meeting. Results indicated use of tranexamic acid was associated with a significant reduction in serious bleeding events and need for blood transfusion while a statistical analysis determined there was a more than 95% probability of safety compared to placebo therapy for comparisons of adverse events.¹

The 7490 patients included in the current study were recruited from 110 hospitals in 22 countries. Of the 7490 included in the study, 3742 patients were randomized to a hypotension-avoidance strategy and 3748 were randomized to a hypertension-avoidance strategy. Of note, in the hypotension-avoidance group, the intraoperative mean arterial pressure targets were 80 mmHg or greater and 60 mmHg or greater for the hypotension-avoidance and hypertension-avoidance groups, respectively.¹

Per trial protocol, patients using the hypotension-avoidance strategy did not take ACE inhibitors or ARBs from the night before surgery through postoperative day 2, resuming them 3 days after surgery. Patients using the hypertension-avoidance strategy received all usual preoperatively, including on the morning of surgery, and postoperatively.¹

The primary outcome of interest for the current study was a composite of vascular death and nonfatal myocardial infarction after noncardiac surgery, stroke, and cardiac arrest at 30 days. Investigators pointed out outcome adjudicators were masked to treatment assignment.¹

Upon analysis, results indicated a primary outcome event occurred among 13.9% (n=520) in the hypotension-avoidance group compared to 14.0% (n=524) in the hypertension avoidance group (Hazard ratio [HR], 0.99 [95% confidence interval [CI], 0.88-1.12]; P=.92). Investigators highlighted this correlates to an absolute risk difference of 0.08 percentage points.¹

In their conclusion, investigators called for additional research to further evaluate preoperative interventions with the ability to modify hemodynamics to an extent where it contributes to a favorable effect on clinical outcomes.¹

“POISE-3 addressed common questions that confront perioperative care physicians and showed that intraoperative MAPs of 80 mmHg or greater versus 60 mmHg or greater and perioperative withholding or continuing of long-term antihypertensive medications did not substantially affect perioperative hemodynamics or vascular complications,” investigators added.¹ “Further research is needed to identify and evaluate perioperative interventions that can modify hemodynamics to an extent and in the direction that will lead to a favorable effect on major clinical outcomes.”

In an accompanying editorial, Jason Shiffermiller, MD, MPH, of the Division of Hospital Medicine at the University of Nebraska Medical Center, and Christopher Whinney, MD, of the Department of Hospital Medicine at the Cleveland Clinic Lerner College of Medicine, noted the results of the study underline the importance of a personalized medicine approach to management of this patient population.²

“Despite the substantial addition that this trial makes to the existing literature, the decision about whether to hold selected antihypertensive medications for surgery remains a nuanced, individualized decision,” wrote the pair.² “The degree and possibly the duration of hypotension experienced by patients in this study may have been inadequate to affect the outcomes that were studied."

References

1. Marcucci M, Painter TW, Conen D, et al. Hypotension-Avoidance Versus Hypertension-Avoidance Strategies in Noncardiac Surgery : An International Randomized Controlled Trial [published online ahead of print, 2023 Apr 25]. Ann Intern Med. 2023;10.7326/M22-3157. doi:10.7326/M22-3157
2. Shiffermiller JF, Whinney CM. Perioperative Management of Antihypertensive Agents: More Answers or More Questions? [published online ahead of print, 2023 Apr 25]. Ann Intern Med. 2023;10.7326/M23-0745. doi:10.7326/M23-0745