Continuous positive airway pressure as a promoter of laryngospasm during halothane anesthesia.

Abstract

Twenty mongrel dogs were anesthetized with halothane 2.0%, 1.25%, 0.94%, and 0.63% in oxygen. Thyroarytenoid (TA) and posterior cricoarytenoid (PCA) electromyography (EMG) tracings were recorded with the animal at rest, following mechanical irritation of the glottis, and during 20 mm Hg continuous positive airway pressure (CPAP) following either airway occlusion or hyperventilation. Adductor laryngospasm was defined as continuous tonic TA EMG activity, silent PCA EMG, and vocal cord adduction. Abductor laryngospasm was defined as continuous tonic PCA EMG activity, silent TA EMG, and vocal cord abduction. Combined laryngospasm was defined as continuous tonic PCA and TA EMG activity, with variable vocal cord position. The incidence of adductor laryngospasm following mechanical irritation was 30% to 50%. The combined incidence of laryngospasm during application of CPAP following airway occlusion or hyperventilation was 25% to 50%, and differed from the incidence of irritation-induced adductor laryngospasm by 5% or less at the same anesthetic level. Continuous positive airway pressure appears to be a stimulant of laryngeal muscle spasm comparable to mechanical irritation of the glottis.

• Authors: D A Silva, I Sanders
• Journal: The Annals of otology, rhinology, and laryngology (Ann Otol Rhinol Laryngol) Vol. 101 Issue 11 Pg. 893-6 (Nov 1992) ISSN: 0003-4894 [Print] United States
• PMID: 1444096 (Publication Type: Comparative Study, Journal Article)

Chemical References

• Halothane

Topics

• Airway Obstruction (physiopathology)
• Anesthesia, Inhalation
• Animals
• Biomechanical Phenomena
• Disease Models, Animal
• Dogs
• Glottis
• Halothane
• Hyperventilation (physiopathology)
• Laryngismus (etiology)
• Physical Stimulation
• Positive-Pressure Respiration (adverse effects)