The Effect of Desflurane vs Sevoflurane on Perioperative Respiratory Complications in Laryngeal Mask Airway Anesthesia

Study Overview
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Brief Summary
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The effects of desflurane versus sevoflurane in adult patients undergoing LMA anesthesia on respiratory events during a less than 2-hour elective surgery.

Detailed Description
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Laryngeal Mask Airway (LMA) anesthesia is generally performed for ambulatory surgery to avoid the use of neuromuscular blocking agents and to facilitate rapid emergence from anesthesia. Inhaled anesthetics are simply and popularly used during maintenance of anesthesia. The two most recent volatile anesthetic agents, desflurane and sevoflurane, are the two most commonly used in clinical practice for an ambulatory setting. Desflurane is the volatile agent with low blood: gas partition coefficient (0.42). Desflurane's uptake and elimination from the body of a patient are rapid, which results in a fast onset of anesthesia and a fast recovery from anesthesia. This property provides desflurane as an ideal agent for the ambulatory anesthesia. However, its pungent odor is concerned to irritate the upper airway and may cause significant respiratory complications. Sevoflurane has a blood: gas partition coefficient of 0.65, which is slightly greater than desflurane. The major advantage over desflurane is the better scent. It is considered to be less airway irritation in LMA anesthesia with smooth induction and recovery. The limitation of desflurane on its odor leads to a controversy if desflurane is similar to or worse than sevoflurane for LMA anesthesia. This is non-inferiority study designed to compare the occurrence of respiratory complications between desflurane and sevoflurane during LMA anesthesia.

Official Title
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The Effect of Desflurane vs Sevoflurane on Perioperative Respiratory Complications in Laryngeal Mask Airway Anesthesia: A Prospective Randomized Double-blinded Control Study

Conditions
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Anesthesia; Adverse Effect, Laryngeal Masks, Respiratory System Abnormalities

Intervention / Treatment
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* Drug: Desflurane
* Drug: Sevoflurane


Participation Criteria
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Eligibility Criteria
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Inclusion criteria: Patients with American Society of Anesthesiologists physical status classification of I-III Elective surgery Surgery with expected duration of operation of less than 2 hours Surgery that anesthesiologist plans to use laryngeal mask airway during anesthesia Exclusion Criteria: Patients with gastroesophageal reflux disease Patients with hiatal hernia Patients with history of upper respiratory tract infection within 1 month before surgery Heavy smoker (> 20 cigarettes per day) Obese patients with body mass index > 30kg/m2 Pregnant patients Unable to provide a written informed consent patients Surgery requiring non-depolarizing muscle relaxants

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 75 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: Diagnostic
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Desflurane<br>Desflurane group: The rule of 24 will be applied, which means that the fresh gas flow (l/ min) multiplied by volume percent of desflurane must not exceed 24. Therefore, once the patients return of spontaneous ventilation, an anesthesiologist turns on oxygen 1 l/ min, nitrous oxide 1 l/ min, and desflurane 12 vol% for 1-2 minutes. When the end-tidal desflurane reaches 3-3.5% (approximately 0.5 MAC), the anesthesiologist will decrease oxygen and nitrous oxide to each 0.5 l/ min and desflurane to 6 vol% (1 MAC). Desflurane concentration will be adjusted to maintain the end-tidal desflurane around 3-6% (0.5-1 MAC). | Drug: Desflurane<br>* Desflurane is the volatile agent with low blood: gas partition coefficient (0.42), its uptake and elimination from the body of a patient are rapid, which results in a fast onset of anesthesia and a fast recovery from anesthesia. This property provides desflurane as an ideal agent for the ambulatory anesthesia. However, its pungent odor is concerned to irritate the upper airway and may cause significant respiratory complications.<br>* Other names: Des;|
| Active Comparator: Sevoflurane<br>Sevoflurane group: The oxygen and nitrous oxide each 1 l/min will be turned on with sevoflurane 4 vol% for 1-2 minutes or until the end-tidal sevoflurane reach 1-1.2% (approximately 0.5 MAC). After that, the flow of oxygen and nitrous oxide is reduced to each 0.5 l/ min and concentration dial of sevoflurane is set to 2 vol% (1 MAC). During the operation, sevoflurane concentration will be adjusted to maintain the end-tidal sevoflurane around 1-2% (0.5-1 MAC) | Drug: Sevoflurane<br>* Sevoflurane has a blood: gas partition coefficient of 0.65, which is slightly greater than desflurane. The major advantage over desflurane is the better scented. It is considered to be less airway irritation in LMA anesthesia with smooth induction and recovery.<br>* Other names: Sev;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Occurrence of respiratory complications | Respiratory complications are coughing, breath holding, laryngospasm, bronchospasm, and desaturation | From the beginning of operation until 30 minutes after the operation | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Time of eye opening | It is the time from discontinuation of anesthetic to the eye opening on verbal command. | Within 30 minutes after the end of operation | 
| Time to follow motor command | It is the time from discontinuation of anesthetic to hand squeezing. | Within 30 minutes after the end of operation | 
| Time of LMA removal | It is the time from discontinuation of anesthetic to removal of LMA. | Within 30 minutes after the end of operation | 
| Frequency of postoperative nausea and vomiting (PONV) | It is a number of patients with PONV in the early post-anesthetic period. | Within 2 hours after operation | 
| Changes of blood pressure during anesthesia | Non-invasive blood pressure will be recorded at the beginning of anesthesia, every 15 minutes during anesthetic maintenance, and at the time of LMA removal. | Every 15 minutes, from the beginning of operation until 30 minutes after the operation | 
| Changes of heart rate during anesthesia | Heart rate will be recorded at the beginning of anesthesia, every 15 minutes during anesthetic maintenance, and at the time of LMA removal. | Every 15 minutes, from the beginning of operation until 30 minutes after the operation | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Desflurane, Sevoflurane, Respiratory Complications