Effect of added dead space on sleep disordered breathing at high altitude.
Sleep Med
; 13(6): 663-7, 2012 Jun.
Article
em En
| MEDLINE
| ID: mdl-22503005
ABSTRACT
OBJECTIVE:
Sleep disordered breathing with central apnea or hypopnea frequently occurs at high altitude and is thought to be caused by a decrease in blood CO(2) level. The aim of this study was to assess the effects of added respiratory dead space on sleep disordered breathing.METHODS:
Full polysomnographies were performed on 12 unacclimatized swiss mountaineers (11 males, 1 female, mean age 39 ± 12 y.o.) in Leh, Ladakh (3500 m). In random order, half of the night was spent with a 500 ml increase in dead space through a custom designed full face mask and the other half without it.RESULTS:
Baseline data revealed two clearly distinct groups one with severe sleep disordered breathing (n=5, AHI>30) and the other with moderate to no disordered breathing (n=7, AHI<30). DS markedly improved breathing in the first group (baseline vs DS) apnea hypopnea index (AHI) 70.3 ± 25.8 vs 29.4 ± 6.9 (p=0.013), oxygen desaturation index (ODI) 72.9 ± 24.1/h vs 42.5 ± 14.4 (p=0.031), whereas it had no significant effect in the second group or in the total population. Respiratory events were almost exclusively central apnea or hypopnea. Microarousal index, sleep efficiency, and sleep architecture remained unchanged with DS. A minor increase in mean PtcCO(2) (n=3) was observed with DS.CONCLUSION:
A 500 ml increase in dead space through a fitted mask may improve nocturnal breathing in mountaineers with severe altitude-induced sleep disordered breathing.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Terapia Respiratória
/
Síndromes da Apneia do Sono
/
Espaço Morto Respiratório
/
Doença da Altitude
/
Montanhismo
Tipo de estudo:
Clinical_trials
Limite:
Adult
/
Female
/
Humans
/
Male
/
Middle aged
Idioma:
En
Revista:
Sleep Med
Assunto da revista:
NEUROLOGIA
/
PSICOFISIOLOGIA
Ano de publicação:
2012
Tipo de documento:
Article
País de afiliação:
Suíça