RT Journal Article
SR Electronic
T1 Effects of high-altitude periodic breathing on sleep and arterial oxyhaemoglobin saturation
JF European Respiratory Journal
JO Eur Respir J
FD European Respiratory Society
SP 408
OP 413
DO 10.1183/09031936.98.12020408
VO 12
IS 2
A1 A Salvaggio
A1 G Insalaco
A1 O Marrone
A1 S Romano
A1 A Braghiroli
A1 P Lanfranchi
A1 V Patruno
A1 CF Donner
A1 G Bonsignore
YR 1998
UL http://erj.ersjournals.com/content/12/2/408.abstract
AB This study aimed to investigate the effect of periodic breathing (PB) at high altitude on sleep structure and arterial oxygen saturation (Sa,O2). Five healthy subjects underwent polysomnographic studies at sea level, and during the first and the fourth week of sojourn at 5,050 m. Their breathing pattern, sleep architecture and Sa,O2 were analysed. PB was detected in the high-altitude studies during nonrapid eye movement (NREM) sleep and tended to increase from the first to the fourth week. Stages 3-4 were absent in four subjects at the first week, but only in one at the fourth week, irrespective of the amount of PB. The arousal index was 11.6+/-3.8 at sea level, 30.1+/-15.5 at the first week at altitude and 33.0+/-18.2 at the fourth week. At altitude, arousal index in NREM sleep was higher during PB than during regular breathing. In NREM sleep, the mean highest Sa,O2 levels in NREM epochs with PB were higher than in those with regular breathing by 2.8+/-1.7% at the first week and 2.9+/-1.5% at the fourth week (p<0.025). From the first to the fourth week, mean Sa,O2 increased significantly during wakefulness (5.6%), NREM (5.2% with regular breathing and 5.3% with PB) and rapid eye movement sleep (7.6%). The data demonstrate a slight role of periodic breathing in altering sleep architecture at high altitude and also show that periodic breathing induces only a minor improvement in arterial oxygen saturation during nonrapid eye movement sleep.