Effect of Phenylephrine During Shoulder Arthroscopic Surgery

Study Overview
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Brief Summary
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The purpose of this study is to determine whether phenylephrine infusion are effective in the prevention of hypotension after changing position to beach chair position during general anesthesia for shoulder arthroscopic surgery. Investigators hypothesized that by increasing arterial blood pressure with phenylephrine infusion, incidence of hypotension would be decreased.

Detailed Description
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The beach chair position is associated with hypotension, risk of cerebral hypoperfusion, and cerebral injury. Sixty-six patients undergoing elective shoulder arthroscopic surgery are randomized to receive either phenylephrine low dose (0.5 mcg/kg/hr), phenylephrine high dose (1.0 mcg/kg/min), or normal saline 5 minute before being placed in the beach chair position. General anesthesia is induced with propofol, remifentanil and rocuronium (0.6 mg/kg) and the trachea intubated. Anesthesia is maintained with sevoflurane and remifentanil targeting for a BIS value 40-60. After hemodynamic stabilization, patients received on infusion of either phenylephrine high dose (1.0 mcg/kg/min), phenylephrine low dose (0.5 mcg/kg/hr) or normal saline 5 minute before being placed in the beach chair position. Following 15 minutes of infusion study drugs, measurements of mean arterial blood pressure and cardiac function (stroke volume variation, stroke volume index, and cardiac index) using Vigileo/Flotrac system were made.

Official Title
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Effect of Phenylephrine Infusion for Preventing Hypotension During Shoulder Arthroscopic Surgery in the Beach Chair Position

Conditions
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Disorder of Shoulder, Anesthesia

Intervention / Treatment
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* Drug: Phenylephrine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: shoulder arthroscopic surgery undergone beach chair position Exclusion Criteria: History of cerebrovascular event, significant cardiac disease (New York Heart Association symptoms class ≥ 3) uncontrolled hypertensive patients. American society of anesthesiologist class 4,5

Ages Eligible for Study
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Minimum Age: 20 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: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Low dose phenylephrine<br>phenylephrine 0.5 mcg/kg/min | Drug: Phenylephrine<br>* Patients is received phenylephrine 1.0 mcg/kg/min or 0.5 mcg/kg/min for 5 minutes before being placed in the beach chair position.<br>* Other names: Phenylephrine hydrochloride;|
| Experimental: High dose phenylephrine<br>phenylephrine 1.0 mcg/kg/min . | Drug: Phenylephrine<br>* Patients is received phenylephrine 1.0 mcg/kg/min or 0.5 mcg/kg/min for 5 minutes before being placed in the beach chair position.<br>* Other names: Phenylephrine hydrochloride;|
| No Intervention: Normal saline<br>normal saline for 5minutes | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of hypotension | After being beach chair position during shoulder arthroscopic surgery. We measure the incidence of hypotension with invasive blood pressure (Arterial line catheterization). | 30 minutes | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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shoulder, phenylephrine, hypotension