Effect of Personalized Blood Pressure Management on Postoperative Complications and Mortality in High-risk Patients Undergoing Major Non-cardiac Surgery: a Randomized Controlled Trial

Anesthesia- and surgery-related complications and mortality constitute a critical global public health burden. Annually, over 300 million surgical procedures are performed worldwide, with postoperative complications and mortality standing as predominant contributors to adverse outcomes. High-risk populations, particularly elderly individuals and patients with cardiovascular comorbidities, exhibit markedly elevated incidences of postoperative myocardial injury (MINS), acute kidney injury (AKI), and mortality. Refinement of perioperative management protocols-especially precision-guided hemodynamic control-has emerged as a pivotal strategy for optimizing patient prognosis.

Intraoperative hypotension (IOH), a pervasive clinical phenomenon affecting 40%-90% of surgical cases, is conventionally defined through either absolute thresholds (e.g., systolic blood pressure (SBP) <90 mmHg or mean arterial pressure (MAP) <65 mmHg) or relative reductions from baseline values (>20% decline). Its high prevalence and association with end-organ hypoperfusion have positioned IOH as a central concern in perioperative care. Substantial observational evidence links IOH severity/duration to ischemic organ injuries (MINS, AKI) and long-term morbidity. Nevertheless, inherent limitations of observational designs-particularly residual confounding-preclude definitive causal inferences. Notably, randomized controlled trials (RCTs) investigating goal-directed hemodynamic interventions demonstrate inconsistent clinical benefits, underscoring the imperative to clarify causal mechanisms between IOH and organ injury.

This causal ambiguity arises from two unresolved scientific questions:

1. Threshold personalization deficit: Current paradigms predominantly apply population-based fixed thresholds (e.g., MAP ≥75-80 mmHg vs. ≥60 mmHg), disregarding interindividual hemodynamic variability. Although The Intraoperative Norepinephrine to Control Arterial Pressure (INPRESS) study used personalized blood pressure targets, its approach of measuring baseline blood pressure during a single clinic visit conflicts with current evidence. Research shows that 24-hour ambulatory monitoring is the most reliable method to capture an individual's true baseline blood pressure and daily fluctuations.
2. Therapeutic strategy limitations: Conventional protocols emphasizing aggressive vasopressor use to achieve arbitrary pressure targets may inadvertently increase complications like anastomotic leakage and AKI. Furthermore, the multifactorial etiology of IOH-encompassing hypovolemia, vasoplegia, and impaired cardiac contractility-demands etiology-specific management algorithms rather than universal interventions.

In light of current evidence, perioperative hypotension management demands personalized strategies. To address this need, the investigators propose a multicenter randomized controlled trial (RCT) that pioneers the integration of ambulatory blood pressure monitoring (ABPM) with etiology-specific intervention protocols. This study aims to clarify the clinical benefits of individualized blood pressure management and establish high-quality evidence to advance precision anesthesia practices in perioperative care.