Home
Search
Study Topics
Glossary
|
|
|
|
|
Sponsored by: |
University Hospital, Basel, Switzerland |
---|---|
Information provided by: | University Hospital, Basel, Switzerland |
ClinicalTrials.gov Identifier: | NCT00665418 |
To describe laryngeal and respiratory reflex responses after controlled laryngeal stimulation in pediatric patients anesthetized with sevoflurane and to compare the evoked responses at two levels of anesthesia. To determine whether laryngeal and respiratory reflex responses after controlled laryngeal stimulation are completely suppressed in subjects when anesthetized with a MACEI95 (EI = endotracheal intubation) sevoflurane
Hypothesis: The incidence of apnea with laryngospasm evoked by laryngeal stimulation will be reduced by 20% (from 25% to 5%) when the end-tidal concentration of sevoflurane is increased from 2.5% (MAC50) to 4.7% (MACEI95)
Condition | Intervention | Phase |
---|---|---|
Laryngospasm |
Drug: sevoflurane |
Phase IV |
Study Type: | Interventional |
Study Design: | Prevention, Open Label, Dose Comparison, Single Group Assignment, Efficacy Study |
Official Title: | Impact of High Concentrations of Sevoflurane on Laryngeal Reflex Responses in Pediatric Patients |
Enrollment: | 40 |
Study Start Date: | February 2008 |
Study Completion Date: | August 2008 |
Primary Completion Date: | August 2008 (Final data collection date for primary outcome measure) |
Arms | Assigned Interventions |
---|---|
1: Experimental |
Drug: sevoflurane
sevoflurane 2.5% versus 4.7% (inhaled concentration) 10min each
|
Induction of anesthesia inhaling sevoflurane is a very common practice in pediatric anesthesia.However, unwarranted exaggerated upper airway defensive reflexes that develop into apnea and laryngospasm with resultant hypoxemia is more common and also more severe. Despite their obvious clinical significance, reflexes that involve the function of the upper airway are only minimally understood and information on such reflexes is scarce in anesthetized humans. Nonetheless, a model was developed by analyzing respiratory variables and endoscopic images after stimulating the laryngeal mucosa with a small amount of distilled water. Clinical experience suggests that laryngeal reflexes occur more frequently under light levels of anesthesia. However, in contrast to other inhalational agents such as halothan, available data for sevoflurane suggest that an inverse correlation of laryngeal responsiveness to depth of hypnosis or end-tidal concentrations of sevoflurane (in adults and children) is less obvious. However, in all previous studies assessing laryngeal reflex responses under sevoflurane only low concentrations of sevoflurane (range of 1.0 - 2.5 Vol%) were examined. This is an important limitation because in clinical practice higher concentrations of sevoflurane are used, especially during manipulation of the airway, while the risk of airway irritation is high.
Thus, the proposed study aims to explore the question whether the occurrence of laryngospasm can be reliably suppressed when high concentrations of sevoflurane are used. Based on results of experiments assessing conditions that facilitate tracheal intubation, it is clear, that increasing the end-tidal concentration of volatile agents obtunds airway reflexes. Regarding intubation conditions, the concept of MACEI 50% or 95% describes the minimum alveolar concentration (MAC) of a volatile anesthetic needed by 50 or 95% of the patients, respectively, to prevent all movement during and immediately after tracheal intubation. The proposed study aims to assess respiratory reflex responses at these levels of anesthesia by analyzing the respiratory variables and endoscopic images. The incidences of well-defined airway reflexes (cough reflex, spasmodic panting, expiration reflex, and apnea with laryngospasm, central apnea) will be examined. Apnea with laryngospasm will be of primary interest in our study and digital video analysis of the glottic opening will allow for a detailed analysis of laryngeal performance.
Ages Eligible for Study: | 25 Months to 84 Months |
Genders Eligible for Study: | Both |
Accepts Healthy Volunteers: | No |
Inclusion Criteria:
Exclusion Criteria:
Responsible Party: | Department of Anesthesia ( Albert Urwyler MD ) |
Study ID Numbers: | UNIBAS_UKBB_ANE_LR4, SNF_3200B0-109322 |
Study First Received: | January 23, 2008 |
Last Updated: | March 11, 2009 |
ClinicalTrials.gov Identifier: | NCT00665418 History of Changes |
Health Authority: | Switzerland: Ethikkommission |
Anesthesia children Larynx |
Anesthetics, Inhalation Otorhinolaryngologic Diseases Respiratory Tract Diseases Anesthetics, General Respiration Disorders Central Nervous System Depressants |
Anesthetics Platelet Aggregation Inhibitors Laryngeal Diseases Laryngismus Sevoflurane |
Otorhinolaryngologic Diseases Physiological Effects of Drugs Respiration Disorders Hematologic Agents Central Nervous System Depressants Anesthetics Pharmacologic Actions Sevoflurane |
Anesthetics, Inhalation Respiratory Tract Diseases Anesthetics, General Therapeutic Uses Platelet Aggregation Inhibitors Laryngismus Laryngeal Diseases Central Nervous System Agents |