Goal-directed Intraoperative Fluid Therapy in High-risk Surgery

Study Overview
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Brief Summary
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This study is aim to assess the effect of goal-directed intraoperative fluid therapy on patient's postoperative incidence rates of complications, length of hospitalization and hospitalization cost. This is an observational study followed cohort study design, due to the two therapies were not randomized assigned to the two cohorts. The details are described as follow.

Detailed Description
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The study will be conducted in patients undergoing either elective laparotomy of gynecological malignancies or elective major orthopaedic surgery under prone position in Peking Union Medical College Hospital. The study included two stages. In the first stage, one cohort of 300 participants with conventional fluid therapy will be involved, in which 150 patients will be selected with laparotomy of gynecological malignancies and150 patients will be selected with orthopedic surgery. All the participants in this stage will follow conventional fluid therapy to direct the amount of intraoperative fluid. Specifically, the fluid will be administered based on the principle crystalloid solution (colloid solution =2-3:1). The total volume of fluid will be adjusted in accordance with blood pressure, heart rate and urine output of each patient. It is a standard procedure in Peking Union Medical College Hospital. Then, the incidence of postoperative complications of each group will be recorded. In addition, sample size will be estimated based on above study's results (estimated 100 participants). In the second stage, goal-directed therapy will be applied to another cohort of 300 participants, in which 150 patients undergoing laparotomy of gynecological malignancies and 150 patients undergoing orthopedic surgery. Specifically, the fluid will be administered based upon real-time monitoring stroke volume variation and cardiac output achieved by the Flo-Trac monitoring system. The incidence of postoperative complications of each group will be recorded.

Official Title
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Effect of Goal-Directed Intraoperative Fluid Therapy on Outcomes Following Laparotomy of Gynecological Malignancies and Orthopedic Surgery

Conditions
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Postoperative Complications, Fluid Overload

Intervention / Treatment
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* Other: Applying goal-directed fluid therapy by continuous hemodynamic monitoring system
* Other: Conventional fluid therapy


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Receiving elective laparotomy of gynecological malignancies (LGM): including cytoreductive surgery of ovarian cancer, radical hysterectomy and staging surgery of endometrial cancer ; Major elective orthopedic surgery (OS): including spinal surgery, revision surgery of hip joints ; Age ≥18 years, American Society of Anesthesiologists physical status I ～IV; No arrhythmia; Receiving general anesthesia; Requiring monitoring of direct blood pressure due to the comorbidities of patients and the nature of surgical procedures. Exclusion Criteria: Emergent surgery; Patients with aortic regurgitation; Patients with aortic stenosis, peripheral arterial diseases or other diseases contradicting to arterial canalizations; Patients with mental disorders or low intelligence quotient; patients who cannot cooperate or refuse to sign the consent.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 90 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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Goal-directed fluid therapy<br>The fluid in group Goal-directed fluid therapy will be administered based upon real-time monitoring stroke volume variation and cardiac output achieved by the Flo-Trac monitoring system. | Other: Applying goal-directed fluid therapy by continuous hemodynamic monitoring system<br>* Applying continuous hemodynamic monitoring system ( Vigileo/Flotrac) to monitor Stroke Volume Variation and Cardiac Output and further manage intra-operative fluid therapy.<br>|
| Conventional fluid therapy<br>The fluid in group Conventional fluid therapy will be administered based on the principle crystalloid solution: colloid solution =2-3:1. The total volume of fluid will be adjusted in accordance with blood pressure, heart rate and urine output of each patient. | Other: Conventional fluid therapy<br>* Applying conventional fluid therapy according to Peking Union Medical College Hospital standard.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| postoperative complications | the incidence of complications related to surgeries 30 days postoperatively. The complications include pneumonia, pulmonary embolism, cardiovascular events (myocardial infarction, heart failure), wound infection, gastrointestinal bleeding,nausea and vomitting，postoperative hemorrhage, ileus, deep venous thrombosis, cerebral infarction, cerebral embolism, cerebral hemorrhage, renal insufficiency and failure. Those complications are defined strictly to the reference published in 2009 New England Journal of Medicine （N Engl J Med. 2009 Oct 1;361:1368-75） | 30 days after the surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| hospital length of stay | the length of stay in hospital，from the hospitalized date to the leave date | participants will be followed for the duration of hospital stay, an expected average of 10 days | 
| hospital expenses | total cost in hospital | 30 days after the surgery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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goal-directed fluid therapy, intraoperative hemodynamics, postoperative complications