Preventive Effect of Leg Wrapping Combined With Trendelenburg Position on Hypotension Induced by Propofol

Study Overview
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Brief Summary
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Although propofol is widely used as an induction agent for a general anesthesia, it can induce a profound hypotension, which leads to the hypo-perfusion of end organs and eventually increases morbidities. Theoretically, applying Trendelenburg position (head down and leg up position) increases cardiac preloads and cardiac outputs. However, in past researches, changing to Trendelenburg position alone is not enough and does not prevent propofol induced hypotension. Previous studies proved that leg wrapping effectively prevent hypotension after neuraxial anesthesia during Cesarean section. The leg wrapping prevents hypotension by increasing vascular resistance of lower extremities. The investigators made a hypothesis that applying both Trendelenburg position and leg wrapping prevent propofol induced hypotension more effectively than either applying Trendelenburg position only or taking no preventive measures.

Detailed Description
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** Study procedure check baseline blood pressure ( systolic, diastolic, mean) and heart rate. apply pre-defined measures to each group(arm) ( summarized in arms and interventions section ) induction using propofol 2mg/kg After bispectral index (BIS) goes below 60 & patient become unconsciousness, inject rocuronium 0.6mg/kg intubate patient between 3 and 4 minutes after propofol injection measure blood pressure ( systolic, diastolic, mean ) & heart rate at 1,2,3,4,5 minutes after propofol injection phenylephrine injection if hypotension develops

Official Title
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Preventive Effect of Leg Wrapping Combined With Trendelenburg Position on Hypotension Induced by Propofol

Conditions
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Hypotension, Propofol

Intervention / Treatment
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* Device: leg wrapping with tension
* Procedure: Trendelenburg position
* Device: leg wrapping without tension
* Procedure: supine position


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: American Society of Anesthesiologist's physiologic status class 1, 2, and 3. under general anesthesia Exclusion Criteria: severe cardiac/pulmonary/liver/renal disease BMI > 30 kg/m2 known or risk factor of increased intraocular pressure or intracranial pressure uncontrolled hypertension high risk for propofol allergy allergies to medications related to anesthesia mechanical difficulties with leg wrapping ( wound on legs, devices on legs ) emergent operation high risk of gastric aspiration ( gastrointestinal obstruction, short nil per os(NPO) time ) patient wearing elastic stocking for therapeutic purpose

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 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 |
| --- | --- |
| Active Comparator: Control<br>leg wrapping without tension & maintain supine position Apply elastic bandages to both legs without tension. Maintain supine position after injecting propofol. After 3 minutes from propofol injection, remove elastic bandages induction using propofol 2mg/kg After bispectral index (BIS) goes below 60 & patient become unconsciousness, inject rocuronium 0.6mg/kg intubate patient between 3 and 4 minutes after propofol injection measure blood pressure ( systolic, diastolic, mean ) & heart rate at 1,2,3,4,5 minutes after propofol injection phenylephrine injection if hypotension develops | Device: leg wrapping without tension<br>* Apply elastic bandages without tension to both legs before injecting propofol. After 3 minutes, remove elastic bandages<br>Procedure: supine position<br>* 1.maintain supine position<br>|
| Experimental: Trendelenburg only<br>leg wrapping without tension & apply Trendelenburg position Apply elastic bandages to both legs without tension. After injecting propofol, apply Trendelenburg position ( 10 degree ) After 3 minutes from propofol injection, remove elastic bandage and revert to supine position. induction using propofol 2mg/kg After bispectral index (BIS) goes below 60 & patient become unconsciousness, inject rocuronium 0.6mg/kg intubate patient between 3 and 4 minutes after propofol injection measure blood pressure ( systolic, diastolic, mean ) & heart rate at 1,2,3,4,5 minutes after propofol injection phenylephrine injection if hypotension develops | Procedure: Trendelenburg position<br>* Apply Trendelenburg position positon of 10 degree after injectin propofol After 3 minutes, change to supine position<br>Procedure: supine position<br>* 1.maintain supine position<br>|
| Experimental: Trendelenburg & leg wrapping<br>leg wrapping with tension & apply Trendelenburg position Apply elastic bandages to both legs with tension. After injecting propofol, apply Trendelenburg position ( 10 degree ) After 3 minutes from propofol injection, remove elastic bandage and revert to supine position. induction using propofol 2mg/kg After bispectral index (BIS) goes below 60 & patient become unconsciousness, inject rocuronium 0.6mg/kg intubate patient between 3 and 4 minutes after propofol injection measure blood pressure ( systolic, diastolic, mean ) & heart rate at 1,2,3,4,5 minutes after propofol injection phenylephrine injection if hypotension develops | Device: leg wrapping with tension<br>* Apply elastic bandages with tension to both legs before injecting propofol. After 3 minutes, remove elastic bandages.<br>Procedure: Trendelenburg position<br>* Apply Trendelenburg position positon of 10 degree after injectin propofol After 3 minutes, change to supine position<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| SBP_2 | systolic blood pressure at 2 minutes from propofol injection | 2 minutes from propofol injection | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Hypotension, Propofol, Trendelenburg, leg wrapping