Implementation of Computer-Assisted Intraoperative Goal-Directed Fluid Therapy

Study Overview
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Brief Summary
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The aim of this study is to compare the implementation of computer-assisted goal directed fluid therapy (GDFT) to standard of care fluid therapy in major abdominal surgery.

Detailed Description
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Fluid therapy is one of the main tools used in anesthesiology to maintain adequate hemodynamic stability. Goal-directed fluid therapy (GDFT) based on cardiac output and/or dynamic parameters of fluid responsiveness (e.g. pulse pressure variation) has been shown to decrease post-operative complications. The main inconvenience of protocol based therapy is its technical complexity which requires considerable time, attention, and vigilance. GDFT assisted by a closed-loop system, when compared to manual GDFT, is associated with a longer preload independent state and could increase clinician adherence to protocol. To this day no study has compared closed-loop assisted GDFT to standard of care. Goal: This study compares the results of the study entitled Crystalloids or Colloids for Goal directed Fluid Therapy With Closed-loop Assistance in Major Surgery (NCT02312999) to a standard of care group (started retrospectively before the first included patient of the above study) where fluid therapy is based only on static variables (e.g. arterial pressure, heart rate, central venous pressure (CVP), and urine output.) These groups consisted of the same population undergoing the same types of surgery. Hypothesis: A protocolized approach using computer-assisted GDFT when compared to standard of care is associated with less fluid administration and less blood transfusions.

Official Title
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Implementation of Computer-Assisted Intraoperative Goal-Directed Fluid Therapy in Major Abdominal Surgery: A Before and After Study

Conditions
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Major Abdominal Surgery

Intervention / Treatment
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* Device: Computer-assisted GDFT
* Other: Standard of care


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Adult patients (over the age of 18) undergoing elective major abdominal surgery that is expected to take longer than 3 hours and requiring general anesthesia. Exclusion Criteria: Patients under 18 years of age Patients not undergoing surgery, requiring anesthesia, or cardiac output monitoring Patients with arrhythmia and/or atrial fibrillation Patients who are allergic to HES (hydroxyethyl starch) Patients with renal insufficiency (serum creatinine of >2 mg/ml) or hepatic dysfunction (liver enzymes >1.5) Patients who has coagulation disorders (values higher than 1.5x normal values) Patients without the capacity to give written informed consent or refusal of consent Pregnancy at time of enrollment.

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: Non-Randomized
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Standard of care<br>This group (started retrospectively before the first included patient of the closed-loop goal-directed fluid therapy group) consists of patients undergoing major abdominal surgery where fluid management is carried out based only on static variables (e.g. arterial pressure, heart rate, CVP, and urine output). | Other: Standard of care<br>* Patients receive fluid management based only on static variables (e.g. arterial pressure, heart rate, CVP, and urine output). This control group (started retrospectively before the first included patient of the closed-loop goal directed fluid therapy group) consists of the same population undergoing the same surgery as the closed-loop GDFT group.<br>|
| Active Comparator: Computer-assisted GDFT<br>This group consists of patients undergoing major abdominal surgery where fluid management is carried out with a closed-loop (automated) system to deliver fluid by a goal-directed fluid therapy (GDFT) standardized protocol. Confer: Crystalloids or Colloids for Goal-directed Fluid Therapy With Closed-loop Assistance in Major Surgery (NCT02312999) | Device: Computer-assisted GDFT<br>* Patients receive fluid therapy via a computer-assisted goal-directed fluid therapy (GDFT) prototype closed-loop (automated) system guided by a cardiac output monitor.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Perioperative fluid administration | Fluid balance during perioperative period | 24 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Length of hospitalisation |  | Every day up to 90 days after hospitalization | 
| Mortality rate |  | 30 days | 
| Transfusion of blood products during hospitalization | In-hospital transfusion during hospitalization | Every day up to 90 days post surgery | 
| Hypotension incidence during surgery | Incidence of hypotension (defined as total case time spent with 20% drop from baseline preoperative blood pressure) | 24 hours | 
| Need of vasopressor | Use of vasopressors during the perioperative period | 24 hours | 
| Renal function - urea level | Urea levels. Measured in a blood sample taken during hospitalization | Every day up to 90 days after hospitalization | 
| Renal function - creatinine level | Creatinine levels. Measured in a blood sample taken during hospitalization | Every day up to 90 days after hospitalization | 
| Postoperative complications | Major complications included cardiac (acute coronary syndrome/ arrhythmia), pulmonary (embolism/edema), gastrointestinal (bowel and surgical anastomotic leak/internal or external fistulas/peritoneal effusions), renal (renal failure requiring dialysis), infectious (peritonitis/ sepsis), coagulation (bleeding), wound dehiscence, stroke, reoperation, readmission, and death. Minor complications included unplanned ICU admission, pneumonia/pleural effusion, deep venous thrombosis, paralytic ileus progressive, renal insufficiency, infection (superficial wound infection/fever/urinary infection) and confusion/delirium. | Every day up to 90 days after hospitalization | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Fluid therapy, Anesthesiology, Major surgery, Goal-directed fluid therapy, Fluid responsiveness, Closed-loop system