Patient Management During Major Abdominal Surgery: an Oxygen Consumption Protocol Compared to Standard Approach

Study Overview
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Brief Summary
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This study compares the actual standard of care with a new protocol to guide hemodynamic optimization during major abdominal surgery, which is more tailored on patient real needs. During general anesthesia metabolic needs of the body are markedly reduced and increase in CO may not be necessary. In addition, excessive fluid administration has been related to worse post-operative outcomes. We divide patients into three groups: the standard treatment group, the NICE protocol group and the intervention group. In this group we use the v-aCO2/CaO2-CvO2 as marker of tissue ability to increase their oxygen consumption in response to increased O2 delivery, and based on this index the administration of fluid. The principal aim is to optimize functional hemodynamics in order to reduce the fluid balance at the end of the surgery.

Official Title
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Patient Management During Major Abdominal Surgery: the Impact of a Hemodynamic Approach Oriented to Oxygen Consumption Optimization Compared to Standard Approach Targeting Preload-dependency and a Clinically-guided Strategy

Conditions
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Hemodynamic Instability

Intervention / Treatment
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* Other: Oxygen consumption optimization


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patients aged > 18 years acquisition of written informed consent Major abdominal surgery (major gastrointestinal surgery: DCP, gastrectomy, Miles, emicolectomy; gynecologic surgery: oncologic surgery) Surgery times ≥ 3 hours Exclusion Criteria: Absolute contraindication to CVC placement pregnant women hepatic surgery laparoscopic surgery Major vascular surgery Dialysis treatment and kidney transplant surgery Severe heart failure (EF ≤ 35%) Emergency 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: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: Standard<br>In this group standard care will be provided to patients undergoing major abdominal surgery, regarding hemodynamic optimization | |
| Active Comparator: NICE group<br>In this arm patients will be treated according to stroke volume optimization described in NICE program | Other: Oxygen consumption optimization<br>* hemodynamic stability will be achieved through exploration of oxygen consumption need of the patient based on CO2gap/CaO2-CvO2 ratio<br>|
| Experimental: Oxygen consumption group<br>In this arm patients will receive hemodynamic optimization based on their oxygen consumption need | Other: Oxygen consumption optimization<br>* hemodynamic stability will be achieved through exploration of oxygen consumption need of the patient based on CO2gap/CaO2-CvO2 ratio<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Perioperative fluid balance | Perioperative fluid balance | surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Survival at 28 days | Patients who survived at 28 days | 28 days after surgery | 
| Survival at hospital discharge | Patient who survived at hospital discharge | 1 day (Hospital discharge) | 
| Post-operative complication | Increase in TnI, need for mechanical ventilation, infection, ICU admission, anastomotic leak, bleeding, AKI | 1 day (Hospital discharge) | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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CO2 gap, oxygen consumption, Stroke volume optimization