The Effect of Low Flow Anesthesia on Postoperative Emergence Agitation in Rhinoplasty

Study Overview
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Brief Summary
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Emergence agitation, defined as restlessness, disorientation, arousal, and/or inconsolable crying, is a common phenomenon seen in the early phase of recovery from general anesthesia; this may cause respiratory depression, nausea and vomiting, as well as an increase in blood pressure, heart rate and myocardial oxygen consumption. Although its pathogenesis remains unclear, ENT (ear, nose and throat) surgical procedures have been reported to have a higher incidence of agitation in both adults and children. In recent years, low-flow inhalation anesthesia has been widely used in adult anesthesia practice. The aim of this study is to compare the effects of low flow anesthesia and normal flow anesthesia on emergence agitation.

Detailed Description
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Emergence agitation, defined as restlessness, disorientation, arousal, and/or inconsolable crying, is a common phenomenon seen in the early phase of recovery from general anesthesia; this may cause respiratory depression, nausea and vomiting, as well as an increase in blood pressure, heart rate and myocardial oxygen consumption. Hypoxia can lead to serious complications such as aspiration pneumonia, bleeding or reoperation. Although its pathogenesis remains unclear, ENT (ear, nose and throat) surgical procedures have been reported to have a higher incidence of agitation in both adults and children. In recent years, low-flow inhalation anesthesia has been widely used in adult anesthesia practice. Low flow anesthesia has many advantages; the consumption of inhalation agents is reduced, the temperature and humidity of the airways are maintained, the cost of anesthesia and pollution caused by atmospheric waste gases are reduced. In addition, because the temperature and humidity of the tracheobronchial tree are preserved, respiratory functions and mucociliary activities are better preserved. In low-flow anesthesia, the concentration of inhaled anesthetics changes very slowly, and their concentration gradually decreases after the administration is terminated. Since the anesthetic concentration will slowly decrease in the low-flow group during termination of anesthesia, the concentration difference between the brain and lungs will be small. In addition, it is known that a longer period between discontinuation of the administration of anesthetic agents and extubation reduces emergence agitation. This seems possible with the low-flow anesthesia technique. The aim of this study is to compare the effects of low flow anesthesia and normal flow anesthesia on emergence agitation.

Official Title
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The Effect of Low Flow Anesthesia on Postoperative Emergence Agitation in Rhinoplasty: A Randomized, Controlled Trial

Conditions
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Emergence Agitation, Anesthetics, Rhinoplasty

Intervention / Treatment
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* Other: : Conventional flow Anesthesia
* Other: Low Flow Anesthesia


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 18-50 years ASA class I-II, scheduled for elective rhinoplasty surgery under general anesthesia Exclusion Criteria: history of allergy to nonsteroidal anti-inflammatory drugs, bleeding diathesis or anticoagulant use, psychiatric drug use, previous rhinoplasty surgery patient refusal

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 50 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Screening
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Placebo Comparator: Conventional group<br>Anesthesia induction will be performed with 2 mg/kg propofol, 1 µg/kg fentanyl and 0.6 mg/kg rocuronium as standard.After intubation, anesthesia will maintained with %40 O2 and sevoflurane at 2% volume. When the sevoflurane concentration reached 1 MAC, the fresh gas flow rate will be brought to 2 L/min. Inhalation anesthetics will be turned off 10 minutes before the end of the operation. The fresh gas flow will be increased to 6 l/min to be 100% O2. At the end of the surgery, the neuromuscular block will be antagonized with neostigmine-atropine. Sedation and agitation will be assessed immediately after extubation. | Other: : Conventional flow Anesthesia<br>* During the initial wash-in period 2 L/min Fresh gas flow will be used.<br>|
| Active Comparator: Low Flow Group<br>anesthesia induction will be performed with 2 mg/kg propofol, 1 µg/kg fentanyl and 0.6 mg/kg rocuronium as standard.After intubation, anesthesia will maintained with %40 O2 and sevoflurane at 2% volume. When the sevoflurane concentration reached 1 MAC, the fresh gas flow rate will be brought to 0.5 L/min. Inhalation anesthetics will be turned off 10 minutes before the end of the operation. The fresh gas flow will be increased to 6 l/min to be 100% O2. At the end of the surgery, the neuromuscular block will be antagonized with neostigmine-atropine. Sedation and agitation will be assessed immediately after extubation. | Other: Low Flow Anesthesia<br>* Fresh gas flow rate will be 0.5 L/min throughout the procedure.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Richmond Agitation-Sedation Scale (RASS) | Sedation and agitation will be assessed immediately after extubation with the Richmond Agitation-Sedation Scale. RASS is divided into 10 levels (score range, -5 to 4, higher scores indicate more agitation) | From extubation to 30 minutes of arrival in the postoperative care unit | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Ramsey Sedation Scale (RSS) | RSS is divided into 6 levels (score range, 1-6, lower scores indicate more agitation). | From extubation to 30 minutes of arrival in the postoperative care unit | 
| Boezaart score | the quality of the operating field in terms of bleeding (Boezaart score),Participating surgeons will rate surgical site visibility from 0 to 5 on the Boezaart rating scale, where 0 is the best and 5 is the worst. | immediate postoperative period | 
| Surgeon satisfaction | . Surgeon satisfaction with the operative field will be rated at the end of surgery using a 5-choice Likert scale: 1 = very bad, 2 = bad, 3 = fair, 4 = good, and 5 = excellent. | immediate postoperative period | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Emergence Agitation, Anesthetics