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The Perinatal Asphyxiated Lamb Model: A Model for Newborn Resuscitation
Published on: August 15, 2018
Active glottal closure during anoxic gasping in lambs
1Pulmonary Research Unit, Department of Surgery, ENT Division, Université de Sherbrooke, Québec, J1H 5N4, Sherbrooke, Canada.
Respiration Physiology
|January 29, 2002
Summary
Laryngeal dynamics, specifically glottal closure, actively maintain high lung volume between gasps in sedated lambs during anoxia. This mechanism did not significantly impact autoresuscitation efficiency in the study.
Area of Science:
- Physiology
- Respiratory System Dynamics
- Anoxic Events
Background:
- Anoxic gasping is a critical survival mechanism during oxygen deprivation.
- Laryngeal function plays a role in respiratory control, but its specific involvement during anoxic gasping requires further elucidation.
- Ketamine sedation is commonly used in animal models for respiratory studies.
Purpose of the Study:
- To assess laryngeal dynamics during anoxic gasping in ketamine-sedated lambs.
- To determine if active glottal closure between gasps maintains high lung volume.
- To investigate the consequences of this high lung volume maintenance on autoresuscitation efficiency.
Main Methods:
- Chronically instrumented lambs (11-15 days old) were subjected to anoxic conditions.
- Glottal constrictor muscle activity, subglottal pressure, and lung volume were recorded.
- Endoscopic observations confirmed glottal closure.
- Anoxic runs with and without tracheostomy were performed to assess autoresuscitation.
Main Results:
- Active glottal closure was confirmed between gasps, maintaining a high lung volume.
- No significant difference was observed in the time to eupnea resumption between conditions.
- Hemodynamic parameters and arterial blood gases showed no significant variations.
Conclusions:
- Sedated lambs actively maintain high lung volume via glottal closure between anoxic gasps.
- The maintenance of high lung volume did not improve autoresuscitation efficiency in this model.
- Further research is needed to fully understand the importance of laryngeal dynamics during gasping.
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