Laryngeal Injuries After Anesthesia Induction With Three Different Sevoflurane Concentrations (Without Muscle Relaxant)

Study Overview
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Brief Summary
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Anesthesia induction and tracheal intubation can be performed with and without neuromuscular blocking agents (NMBAs). Tracheal intubation can be performed with sevoflurane instead of NMBAs; intubating conditions are similar and the incidence of vocal cord injuries are similar, too.

Detailed Description
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We perform tracheal intubation with propofol, remifentanil and sevoflurane; sevoflurane is administered with three dosages. During tracheal intubation intubating conditions are noted. After surgery, all patients are examined by video laryngoscopy; moreover all patients are asked for hoarseness and sore throat.

Official Title
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Laryngeal Injuries After Anesthesia Induction With Three Different Sevoflurane Concentrations (Without Muscle Relaxant)

Conditions
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Other Specified Injuries of Vocal Cord, Sequela

Intervention / Treatment
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* Drug: sevoflurane 1,0
* Drug: sevoflurane 1,2
* Drug: sevoflurane 1,4


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: ear-nose-throat surgery orotracheal intubation for surgery of the ear ASA I-III Exclusion Criteria: obesity allergy against the study drugs patients with a known or suspected difficult airway diseases of the larynx

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: sevoflurane 1,0<br>sevoflurane 1,0: sevoflurane is administered with a concentration of 1,0 MAC | Drug: sevoflurane 1,0<br>* anesthesia induction with propofol, remifentanil, and sevoflurane 1,0 MAC; afterwards tracheal intubation<br>* Other names: sevo 2,0 %;|
| Active Comparator: sevoflurane 1,2<br>sevoflurane 1,2: sevoflurane is administered with a concentration of 1,2 MAC | Drug: sevoflurane 1,2<br>* anesthesia induction with propofol, remifentanil, and sevoflurane 1,2 MAC; afterwards tracheal intubation<br>* Other names: sevo 2,5 %;|
| Active Comparator: sevoflurane 1,4<br>sevoflurane 1,4: sevoflurane is administered with a concentration of 1,4 MAC | Drug: sevoflurane 1,4<br>* anesthesia induction with propofol, remifentanil, and sevoflurane 1,4 MAC; afterwards tracheal intubation<br>* Other names: sevo 3,0 %;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| incidence of vocal cord injuries |  | 24 hours after tracheal intubation | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| incidence of hoarseness |  | 24, 48, and 72 hours after tracheal intubation | 
| incidence of soar throat |  | 24, 48, and 72 hours after tracheal intubation | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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hoarseness, sore throat, intubating conditions, vocal cord injuries, sevoflurane