Laryngeal Reflex Study Under Propofol Anesthesia: Effect of Intravenous Lidocaine

Study Overview
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Brief Summary
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To describe respiratory and laryngeal responses to laryngeal stimulation during propofol anesthesia in children. To determine whether the co-administration of lidocaine blunts these reflex responses. The outcome of primary interest is the reflex laryngospasm. Hypotheses: I: The severity of laryngospasm evoked by laryngeal stimulation is reduced 2 min. after iv. administration on 2mg/kg lidocaine in pediatric patients anesthetized with propofol (3mcg/ml). II:The incidence of laryngospasm elicited by controlled stimulation 10min. after iv. administration of lidocaine is equivalent to the response before the administration of lidocaine.

Detailed Description
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Based on our previous work assessing the laryngeal reflex responses in children, the use of propofol appears to be promising regarding a low incidence of laryngospasm. Compared with a sevoflurane-based anesthesia, the incidence was found to be significantly lower, but there is a high incidence of other reflex responses, such as coughing and expiration reflexes. The use of lidocaine has been advocated to reduce the incidence of laryngospasm in anesthetized children. However, based on clinical studies its effectiveness in the prevention or attenuation of laryngospasm is controversial. In a previous work using a established stimulation model (stimulating the laryngeal mucosa with a small amount of distilled water under direct fiberbronchoscopic observation), we observed a risk reduction of 60% of laryngospasm 2min. after the application of 2mg/kg bolus of lidocaine. This effect had already diminished after 10 min. The laryngeal reflex responses differ largely in children anesthetized with either inhalational anesthetics or with propofol. The impact iv administered lidocaine on laryngeal and respiratory reflex responses in children anesthetized with propofol has not been assessed, although this combination might result in a profound suppression of laryngeal reflex responses.

Official Title
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Impact of Intravenous Lidocaine on Laryngeal Reflex Responses in Pediatric Patients Anesthetized With Propofol

Conditions
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Laryngospasm

Intervention / Treatment
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* Drug: NaCl 0,9%


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 25 - 84 months gender: female / male elective surgery or diagnostic procedure requiring general anesthesia Exclusion Criteria: respiratory infection within the last 2 weeks reactive airway disease under therapy cardiovascular disease neuromuscular disease positive family history of malignant hyperthermia known hypersensitivity to the investigational medical product Participation in another study Inability of the parents to read and understand the participant's information

Ages Eligible for Study
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Minimum Age: 25 Months
Maximum Age: 84 Months

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: larynx assessment under stimulation<br> | Drug: NaCl 0,9%<br>* Propofol 3micrgr/ml (TCI plasma concentration) and NaCl 0,9% 2min. and 10min. application<br>* Other names: Natriumchlorid;|
| Placebo Comparator: Larynx assessment under stimulation<br> | Drug: NaCl 0,9%<br>* Propofol 3micrgr/ml (TCI plasma concentration) and NaCl 0,9% 2min. and 10min. application<br>* Other names: Natriumchlorid;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Occurence of laryngospasm (defined as complete adduction of vocal cords and/or fals cords) with apnea lasting >10sec after laryngeal stimulation |  | 10 min. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Anesthesia, Children, Larynx