Hemodynamic (MAP) Stability

In North America, norepinephrine, ephedrine, and epinephrine have been recommended as first-choice vasopressors for the treatment of spinal hypotension during cesarean delivery. However, in international consensus guidelines, epinephrine was recommended for circulatory collapse only. Phenylephrine infusion is an important therapeutic strategy for preventing spinal-induced hypotension (SIH) in cesarean delivery, as it decreases the incidence of hypotension, nausea, and vomiting. However, high doses may reduce maternal heart rate and cardiac output in a dose-dependent manner. Ephedrine, previously considered the first-choice drug, has both α and β receptor agonistic activity and causes norepinephrine release from sympathetic neurons. Its β1 effect increases heart rate and contractility, but may cause undesirable tachycardia. Tachyphylaxis can develop with repeated doses. Norepinephrine, the biosynthetic precursor of epinephrine, has both potent α and weak β agonist effects, tending to cause bradycardia. Despite a lower incidence of hypotension with prophylactic norepinephrine, PSH still occurs in up to 30% of parturients undergoing cesarean section. The administration of a bolus dose of epinephrine prior to continuous infusion is an unusual practice in obstetric anesthesia, but has been reported to be safe in other contexts and in pregnant women when used for hemodynamic support. Epinephrine has both potent α- and β-adrenoceptor agonist activity. Its β effects could offset reflex decreases in maternal HR and CO during spinal anesthesia for cesarean delivery. Although some studies compared epinephrine infusion with phenylephrine, it remains unclear whether adding an initial bolus of epinephrine before infusion offers superior maternal hemodynamic stability compared to infusion alone.

This study will investigate the impact of using an automated fluid management system on intraoperative fluid therapy in patients undergoing colorectal surgery. The aim is to evaluate whether automated guidance can optimize hemodynamic stability and reduce the incidence of arterial hypotension,

The goal of this clinical trial is to learn if using artificial intelligence to guide intravenous fluid therapy during major cancer surgery can help keep blood pressure more stable compared with usual care in adult patients undergoing major cancer surgery. The main questions it aims to answer are: * Does artificial intelligence-guided fluid therapy reduce hypotensive events during surgery? * Does this approach improve recovery and reduce complications after major cancer surgery? Researchers will compare artificial intelligence-guided fluid therapy with standard fluid management to see if the artificial intelligence-guided approach provides better support during surgery. Participants will: * Undergo major cancer surgery under general anesthesia * Receive either artificial intelligence-guided fluid management or standard fluid management during surgery * Be monitored during and after surgery as part of routine clinical care * Be followed after surgery to assess recovery and possible complications

intraoperative hemodynamic optimization will be based on the percentage of variation of the parameters