Effects of Fluid Therapy on Microcirculatory Reactivity

Study Overview
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Brief Summary
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Through preoperative fluid therapy, to investigate whether it can alleviate the microcirculation dysfunction after induction of anesthesia, and reduce the incidence of perioperative fluid therapy-related complications, thereby accelerating rehabilitation.

Detailed Description
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Patients undergoing minimally invasive coronary artery bypass graft surgery were randomly divided into crystal group, colloid group and control group. The preoperative fluid reactivity was evaluated according to the passive leg lifting test (PLR). When stroke volume increased (△SV)>16%, the patients in the crystal (carbonate Ringer solution) and the colloid group (hydroxyethyl starch solution) were treated with volume therapy, while the control group was not treated with PLR test and volume therapy. Vascular occlusion test was used to observe the effect of anesthesia induction on tissue oxygen saturation recovery slope (RecStO2) after volume therapy, Goal-directed fluid therapy was used during operation, and the postoperative microcirculation function and the incidence of related complications were observed.

Official Title
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Effects of Preoperative Fluid Therapy on Microcirculatory Reactivity in Patients With MIDCAB After General Anesthesia

Conditions
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Microcirculation, Fluid Therapy

Intervention / Treatment
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* Other: crystal therapy
* Other: colloid therapy


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age ≥ 18 years old Plan to undergo elective minimally invasive coronary artery bypass grafting (left anterior descending branch); Sign informed consent Exclusion Criteria: Left ventricular ejection fraction <40% Diabetes Renal insufficiency (serum creatinine>177umol/L) Liver insufficiency (AST, ALT>3 times) Peripheral vascular disease Carotid artery stenosis (>60%) VOT test contraindications (arm deformity, burns, arteriovenous shunt) Use glucocorticoids, vasoactive drugs, inotropic drugs or intra-aortic balloon counterpulsation (IABP) Allergic to colloidal fluids

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: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: Control group<br>There is no treatment before anesthesia induction. | |
| Experimental: Crystal group<br>The fluid reactivity was determined by PLR test before anesthesia induction. The basic value was measured when maintain the head height at 45° for 2 min. and the liquid reactivity value was measured when both legs were raised 45° for 2 min. If △SV >16%, restore the head height to 45°, and 250ml carbonated Ringer's solution was infused (infusion time >10min). | Other: crystal therapy<br>* Infusion of 250ml crystal solution before anesthesia induction<br>|
| Experimental: Colloidal group<br>The fluid reactivity was determined by PLR test before anesthesia induction. The basic value was measured when maintain the head height at 45° for 2 min. and the liquid reactivity value was measured when both legs were raised 45° for 2 min. If △SV >16%, restore the head height to 45°, and 250ml colloidal fluid was infused (infusion time >10min). | Other: colloid therapy<br>* Infusion of 250ml colloid solution before anesthesia induction<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in DesStO2 is assessed | DesStO2(%/min):The downhill slope of StO2 reflects the oxygen consumption rate | The microcirculation function is measured at 4 time points: patients entered the operating room; 5 minutes after volume therapy; 30 minutes after anesthesia induction; and at the end of the operation | 
| Change in tM is assessed | The time for minimum value of StO2 to recover to maximum value of StO2 | The microcirculation function is measured at 4 time points: patients entered the operating room; 5 minutes after volume therapy; 30 minutes after anesthesia induction; and at the end of the operation | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in mean arterial pressure is assessed |  | 4 time points: patients entered the operating room; 5 minutes after volume therapy; 30 minutes after anesthesia induction; and at the end of the operation | 
| Change in heart rate is assessed |  | 4 time points: patients entered the operating room; 5 minutes after volume therapy; 30 minutes after anesthesia induction; and at the end of the operation | 
| Length of hospital stay |  | up to 60 days | 
| Duration of stay in the intensive care unit |  | up to 60 days | 
| Change in HS is assessed | HS(ng/ml): As a valuable clinical biomarker for glycocalyx degradation | 4 time points: patients entered the operating room; 5 minutes after volume therapy; 30 minutes after anesthesia induction; and at the end of the operation | 
| Change in SDC-1 is assessed | SDC-1(ng/ml): As a valuable clinical biomarker for glycocalyx degradation | 4 time points: patients entered the operating room; 5 minutes after volume therapy; 30 minutes after anesthesia induction; and at the end of the operation | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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minimally invasive coronary artery bypass grafting, fuid therapy, microcirculation