TY - JOUR
T1 - Pentobarbital dose-dependently increases respiratory genioglossus muscle activity while impairing diaphragmatic function in anesthetized rats
AU - Eikermann, Matthias
AU - Fassbender, Philipp
AU - Zaremba, Sebastian
AU - Jordan, Amy S.
AU - Rosow, Carl
AU - Malhotra, Atul
AU - Chamberlin, Nancy L.
PY - 2009/6
Y1 - 2009/6
N2 - Background: Anesthetics depress both ventilatory and upper airway dilator muscle activity and thus put the upper airway at risk for collapse. However, these effects are agent-dependent and may involve upper airway and diaphragm muscles to varying degrees. The authors assessed the effects of pentobarbital on upper airway dilator and respiratory pump muscle function in rats and compared these results with the effects of normal sleep. Methods: Tracheostomized rats were given increasing doses of pentobarbital to produce deep sedation then light and deep anesthesia, and negative pressure airway stimuli were applied (n = 11). To compare the effects of pentobarbital with those of natural sleep, the authors chronically instrumented rats (n = 10) with genioglossus and neck electromyogram and electroencephalogram electrodes and compared genioglossus activity during wakefulness, sleep (rapid eye movement and non-rapid eye movement), and pentobarbital anesthesia. RESULTS: Pentobarbital caused a dose-dependent decrease in ventilation and in phasic diaphragmatic electromyogram by 11 ± 0.1%, but it increased phasic genioglossus electromyogram by 23 ± 0.2%. Natural non-rapid eye movement sleep and pentobarbital anesthesia (10 mg/kg intraperitoneally) decreased respiratory genioglossus electromyogram by 61 ± 29% and 45 ± 35%, respectively, and natural rapid eye movement sleep caused the greatest decrease in phasic genioglossus electromyogram (95 ± 0.3%). CONCLUSIONS: Pentobarbital in rats impairs respiratory genioglossus activity compared to the awake state, but the decrease is no greater than seen during natural sleep. During anesthesia, in the absence of pharyngeal airflow, phasic genioglossus activity is increased in a dose-dependent fashion.
AB - Background: Anesthetics depress both ventilatory and upper airway dilator muscle activity and thus put the upper airway at risk for collapse. However, these effects are agent-dependent and may involve upper airway and diaphragm muscles to varying degrees. The authors assessed the effects of pentobarbital on upper airway dilator and respiratory pump muscle function in rats and compared these results with the effects of normal sleep. Methods: Tracheostomized rats were given increasing doses of pentobarbital to produce deep sedation then light and deep anesthesia, and negative pressure airway stimuli were applied (n = 11). To compare the effects of pentobarbital with those of natural sleep, the authors chronically instrumented rats (n = 10) with genioglossus and neck electromyogram and electroencephalogram electrodes and compared genioglossus activity during wakefulness, sleep (rapid eye movement and non-rapid eye movement), and pentobarbital anesthesia. RESULTS: Pentobarbital caused a dose-dependent decrease in ventilation and in phasic diaphragmatic electromyogram by 11 ± 0.1%, but it increased phasic genioglossus electromyogram by 23 ± 0.2%. Natural non-rapid eye movement sleep and pentobarbital anesthesia (10 mg/kg intraperitoneally) decreased respiratory genioglossus electromyogram by 61 ± 29% and 45 ± 35%, respectively, and natural rapid eye movement sleep caused the greatest decrease in phasic genioglossus electromyogram (95 ± 0.3%). CONCLUSIONS: Pentobarbital in rats impairs respiratory genioglossus activity compared to the awake state, but the decrease is no greater than seen during natural sleep. During anesthesia, in the absence of pharyngeal airflow, phasic genioglossus activity is increased in a dose-dependent fashion.
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U2 - 10.1097/ALN.0b013e3181a16337
DO - 10.1097/ALN.0b013e3181a16337
M3 - Article
C2 - 19417601
AN - SCOPUS:67049144600
SN - 0003-3022
VL - 110
SP - 1327
EP - 1334
JO - Anesthesiology
JF - Anesthesiology
IS - 6
ER -