The Effect of Perioperative Cardiac Output-guided GDT on Oxygen Delivery, Consumption, and Microcirculatory Perfusion

Study Overview
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Brief Summary
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Perioperative cardiac output-guided goal-directed therapy (GDT) triggers fluid, vasopressor, and inotrope administration assuming that optimizing cardiac output (i.e., global blood flow) ensures adequate oxygen delivery and microcirculatory perfusion - that are usually not directly monitored during goal-directed therapy. There is increasing evidence that perioperative cardiac output-guided goal-directed therapy may reduce postoperative complications compared to routine hemodynamic management in high-risk patients having major surgery. The effect of cardiac output-guided goal-directed therapy algorithms on perioperative oxygen delivery and consumption as well as microcirculatory perfusion, however, is unknown. The investigators aim to investigate the effect of using different cardiac output-guided goal-directed therapy algorithms on perioperative oxygen delivery and consumption as well as sublingual microcirculatory perfusion compared to routine perioperative hemodynamic management in patients having major abdominal surgery with general anesthesia.

Detailed Description
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Perioperative cardiac output-guided goal-directed therapy (GDT) triggers fluid, vasopressor, and inotrope administration assuming that optimizing cardiac output (i.e., global blood flow) ensures adequate oxygen delivery and microcirculatory perfusion - that are usually not directly monitored during goal-directed therapy. There is increasing evidence that perioperative cardiac output-guided goal-directed therapy may reduce postoperative complications compared to routine hemodynamic management in high-risk patients having major surgery. The effect of cardiac output-guided goal-directed therapy algorithms on perioperative oxygen delivery and consumption as well as microcirculatory perfusion, however, is unknown. With technological advancements a distinct monitoring of oxygen delivery and consumption as well as microcirculatory perfusion in the perioperative period has become possible. Using new technologies, a detailed understanding of the effect of cardiac output-guided goal-directed therapy on perioperative oxygen delivery and consumption as well as microcirculatory perfusion is of vital importance to further develop and improve perioperative hemodynamic treatment strategies. In this pilot randomized-controlled trial, the investigators therefore aim to investigate the effect of using different cardiac output-guided goal-directed therapy algorithms on perioperative oxygen delivery and consumption as well as sublingual microcirculatory perfusion compared to routine perioperative hemodynamic management in patients having major abdominal surgery with general anesthesia.

Official Title
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The Effect of Perioperative Cardiac Output-guided Goal-directed Hemodynamic Therapy (GDT) on Perioperative Oxygen Delivery, Consumption, and Microcirculatory Perfusion in Comparison to Routine Hemodynamic Management

Conditions
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Caridac Output-guided Goal-directed Hemodynamic Therapy, Oxygen Delivery, Oxygen Consumption, Microcirculatory Perfusion, Major Non-cardiac Surgery, Postoperative Acute Kidney Injury, Postoperative Acute Myocardial Injury

Intervention / Treatment
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* Other: Treatment algorithms targeting cardiac output


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Adult patients (≥18 years) having elective major abdominal surgery with general anesthesia Expected duration of surgery at least 120 minutes Planned postoperative monitoring in intensive care unit Exclusion Criteria: Emergency surgery Age <18 years Body weight <50 kg Pregnancy Atrial fibrillation Planned patient positioning in other position than supine position Surgery within the last 30 days Inaccessibility of the head during surgery Peripheral artery disease stage ≥IIb Chronic vasculitis Supraglottic airway management Enterostomy repair surgery

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Cardiac output maximization group<br>Patients will be treated according to a goal-directed therapy protocol aiming at a cardiac output maximization. Detailed protocol adapted from Edwards, M.R., et al., Optimisation of Perioperative Cardiovascular Management to Improve Surgical Outcome II (OPTIMISE II) trial: study protocol for a multicentre international trial of cardiac output-guided fluid therapy with low-dose inotrope infusion compared with usual care in patients undergoing major elective gastrointestinal surgery. BMJ Open, 2019. 9(1): p. e023455. | Other: Treatment algorithms targeting cardiac output<br>* Treatment algorithms targeting maximization or personalization of cardiac output<br>|
| Active Comparator: Cardiac output personalization group<br>Patients will be treated according to a goal-directed therapy protocol aiming at a personalized cardiac output goal determined with preoperative cardiac output assessment. Detailed protocol adapted from Nicklas, J.Y., et al., Personalised haemodynamic management targeting baseline cardiac index in high-risk patients undergoing major abdominal surgery: a randomised single-centre clinical trial. Br J Anaesth, 2020. 125(2): p. 122-132. | Other: Treatment algorithms targeting cardiac output<br>* Treatment algorithms targeting maximization or personalization of cardiac output<br>|
| No Intervention: Routine management group<br>Patients will be treated according to routine hemodynamic management. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Perioperative changes in oxygen delivery | assessed via blood gas analysis | after induction of general anesthesia, during the last 30 minutes of surgery, within 6 hours after surgery, day 1, 2, 3 after surgery | 
| Perioperative changes in oxygen consumption | assessed via indirect calorimetry | baseline awake, after induction of general anesthesia, during the last 30 minutes of surgery, within 6 hours after surgery, day 1, 2, 3 after surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Perioperative changes of microcirculation | assessed via Incident Darkfield technology | baseline awake, after induction of general anesthesia, during the last 30 minutes of surgery, within 6 hours after surgery, day 1, 2, 3 after surgery | 
| Perioperative changes in cardiac output | assessed via pulse wave analysis | baseline awake, after induction of general anesthesia, during the last 30 minutes of surgery, within 6 hours after surgery, day 1, 2, 3 after surgery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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non-cardiac surgery, oxygen consumption, oxygen delivery, microcirculatory perfusion, goal-directed hemodynamic therapy