The Effect of Vasopressors on Cerebral Oxygentaion During Off Pump CABG

Study Overview
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Brief Summary
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The purpose of this study is to analyze the changes in cerebral oxygen saturation during the use of three vasopressors, phenylephrine, norepinephrine, and vasopressin, which are currently used during coronary artery bypass grafting.

Official Title
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The Effect of Phenylephrine, Norepinephrine and Vasopressin on Cerebral Oxygentaion During Off Pump CABG: A Pilot Study

Conditions
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Cerebral Oxygen Saturation

Intervention / Treatment
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* Drug: Phenylephrine
* Drug: Norepinephrine
* Drug: Vasopressin


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients undergoing off pump coronary artery bypass. Exclusion Criteria: Patient refusal Preoperative vasopressor use Preoperative mechanical circulatory support Concurrent cerebrovascular or head and neck surgery Technical difficulty of measuring brain oxygen saturation Redo coronary artery bypass surgery

Ages Eligible for Study
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Minimum Age: 19 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: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Phenylephrine<br> | Drug: Phenylephrine<br>* Continuous infusion of Phenylenphrine 250 μg/mL (=Phenylephrine 10mg * 5@ + D5W 200 mL) if mean BP < 60mmHg. Initial rate: 0.42 μg/kg/min (=0.1 mL/kg/hr) Increment by 0.21 μg/kg/min (=0.05 mL/kg/hr) if mean BP < 60mmHg after 5 minutes Maximum rate: 3.33 μg/kg/min (=0.8 mL/kg/hr)<br>|
| Experimental: Norepinephrine<br> | Drug: Norepinephrine<br>* Continuous infusion of Norepienphrine 20 μg/mL (=NE 4mg * 1@ + D5W 200 mL) if mean BP < 60mmHg. Initial rate: 0.03 μg/kg/min (=0.1 mL/kg/hr) Increment by 0.015 μg/kg/min (=0.05 mL/kg/hr) if mean BP < 60mmHg after 5 minutes Maximum rate: 0.24 μg/kg/min (=0.8 mL/kg/hr)<br>|
| Experimental: Vasopressin<br> | Drug: Vasopressin<br>* Continuous infusion of Vasopressin 0.1 u/mL (=Vasopressin 20u * 1@ + D5W 200 mL) if mean BP < 60mmHg. Initial rate: 0.01 u/kg/hr (=0.1 mL/kg/hr) Increment by 0.005 u/kg/hr (=0.05 mL/kg/hr) if mean BP < 60mmHg after 5 minutes Maximum rate: 0.08 u/kg/hr (=0.8 mL/kg/hr)<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Cerebral oxygen saturation (%) | continuous monitoring of cerebral oxygen saturation during surgery | during surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| blood pressure | systolic/diastolic/mean blood pressure(mmHg) | during surgery | 
| heart rate | heart rate(/min) | during surgery | 
| cardiac index | cardiac index (L/min) | during surgery | 
| Total amount of infused drug | Propofol, remifentanil, vasoacitve drugs | during surgery | 
| Input/output | Urine output, blood loss, amount of fluid and transfusion | during surgery | 
| Sublingual microscopy | using SDF imaging device | 1) After induction, 2) lateral wall or posterior wall anastomosis (if possible) 3) skin closure | 
| Vascular occlusion test | using InspectraTM StO2 | 1) After induction, 2) lateral wall or posterior wall anastomosis (if possible) 3) skin closure | 
| Troponin I | Troponin I (ng/mL) | during surgery, at ICU admission, 24 hours / 48 hours after ICU admission | 
| lactate | lactate (mmol/L) | during surgery, at ICU admission, 24 hours / 48 hours after ICU admission | 
| creatinine | creatinine (mg/dL) | during surgery, at ICU admission, 24 hours / 48 hours after ICU admission | 
| albumin | albumin (g/dL) | during surgery, at ICU admission, 24 hours / 48 hours after ICU admission | 
| NGAL | NGAL (ng/mL) | during surgery, at ICU admission, 24 hours / 48 hours after ICU admission | 
| MACCE | Major adverse cardiac and cerebrovascular events | until 1 year after surgery | 
| AKI/RRT | renal complication | until 1 year after surgery |