This study is a multicenter randomized controlled trial comparing two strategies of mean arterial blood pressure management (MAP ≥ 80mmHg vs MAP ≥ 65 mmHg) in high-risk surgical patients undergoing elective laparotomic/laparoscopic surgery.

Intraoperative hypotension has been associated with major postoperative complications after non-cardiac surgery. However, is is still unclear the optimal intraoperative mean arterial pressure (MAP) target in the subgroup of those patient with an history of hypertension at home, and at risk of developing postoperative complications.

The objective of this study is to assess the effects of an intraoperative blood pressure management strategy aiming at keeping the MAP ≥ 80mmHg), as compared to the conventional practice (to maintain intraoperative MAP ≥ 65mmHg), on a composite outcome considering the death rate and the incidence of major events in patient scheduled for elective laparotomic/laparoscopic surgery.

The primary outcome is a composite of 30-days from operation mortality rate and at least one major organ dysfunction including the renal, respiratory, cardiovascular and neurologic systems or new onset of sepsis and septic shock occurring by day 7 after surgery.

Inclusion criteria (all the following)

1. Adult patients ≥ 60 years
2. History of chronic hypertension requiring home therapy.
3. Scheduled for major elective abdominal surgery (laparoscopic, robotic or laparotomic)
4. Expected surgical duration of at least 3 hours.
5. Needing invasive arterial and hemodynamic monitoring as decided by the attending anesthetist, according to the rules of good clinical practice of each involved center.

AND

At increased risk of postoperative complications (at least one of the following):

1. American Society of Anesthesiologists (ASA) class 3 or 4
2. Known or documented history of coronary artery disease (angina, myocardial infarction or acute coronary syndrome).
3. Known or documented history of peripheral vascular disease.
4. Known or documented history of heart failure requiring treatment.
5. Ejection fraction less than 30% (echocardiography)
6. Signs of diastolic moderate to severe dysfunction or chronic hypertensive cardiomyopathy (echocardiography)
7. Moderate or severe valvular heart disease (echocardiography)
8. Diagnosis of Chronic Obstructive Pulmonary Disease (COPD) Radiographically confirmed or according to Global Initiative for Chronic Obstructive Lung Disease (GOLD) criteria.
9. Diabetes currently treated with an oral hypoglycemic agent and/or insulin
10. Morbid obesity (BMI ≥35 kg/m2)
11. Preoperative serum albumin <30 g/l
12. Anaerobic threshold (if done) <14 ml/kg/min
13. Exercise tolerance equivalent to six metabolic equivalents (METs) or less as defined by American College of Cardiology/American Heart Association guidelines

Exclusion criteria

1. Refusal of consent
2. Chronic kidney disease with glomerular filtration rate <30 ml/min/1.73 m2 or requiring renal-replacement therapy for end-stage renal disease
3. Acute cardiovascular event, including acute or decompensated heart failure and acute coronary syndrome (within prior 30 days).
4. Urgent or time-critical surgery
5. Aortic or Renal vascular surgery (including nephrectomy)
6. Liver Surgery
7. Neurosurgery
8. Surgery for palliative treatment only or ASA physical status 5
9. Pregnancy

The trial intervention is not blinded for investigators, clinical staff, and patients, as blinding intraoperative MAP target is not feasible. The physicians of each center assessing all postoperative outcomes will be masked for the allocation.