Hypotension Prediction Index software for management of hypotension during moderate- to high-risk noncardiac surgery: Protocol for a randomized trial

Background: Hypotension is associated with serious complications, including myocardial infarction, acute kidney injury, and mortality. Consequently, predicting and preventing hypotension may improve outcomes. We will therefore determine if use of a novel hypotension prediction tool reduces the duration and severity of hypotension in patients having non-cardiac surgery. Methods/design: We will conduct a two-center, pragmatic, randomized controlled trial (N = 213) in noncardiac surgical patients > 45 years old who require intra-arterial blood pressure monitoring. All participating patients will be connected to a Flortrac IQ sensor and EV1000 platform (Edwards Lifesciences, Irvine). They will be randomly assigned to blinded or unblinded arms. The Hypotension Prediction Index (HPI) and advanced hemodynamic information will be universally recorded, but will only be available to clinicians when patients are assigned to unblinded monitoring. The primary outcome will be the effect of HPI software guidance on intraoperative time-weighted average mean arterial pressure under a threshold of 65 mmHg, which will be assessed with a Wilcoxon-Mann-Whitney 2-sample, two-tailed test. Discussion: Our trial will determine whether the Hypotension Prediction Index and associated hemodynamic information substantively reduces hypotension during non-cardiac surgery.