M. Gugger et al., AROUSAL RESPONSES TO INSPIRATORY RESISTIVE LOADING DURING REM AND NON-REM SLEEP IN NORMAL MEN AFTER SHORT-TERM SLEEP FRAGMENTATION DEPRIVATION/, Schweizerische medizinische Wochenschrift, 128(18), 1998, pp. 698-702
The arousal response to inspiratory resistive loading in normal men is
known to be high during REM sleep compared to non-REM sleep. We inves
tigated whether we could observe the same pattern, i.e. brisk arousal
from REM sleep compared to non-REM sleep, in normal subjects who had u
ndergone shortterm sleep fragmentation/deprivation prior to the invest
igation. The arousal response to the repeated application of an extern
al inspiratory resistance of 25 cm H2O/l/s was determined during REM a
nd non-REM sleep in 10 healthy men after a single night with 4 hours o
f acoustically fragmented sleep. The percentage of arousals to non-aro
usals occurring within 2 minutes of the load application was significa
ntly higher during REM sleep than during either of the non-REM sleep s
tages 2 and 3/4 and decreased significantly from stage REM to stage 2
and from stage 2 to stage 3/4. The mean time to arousal in REM was sig
nificantly shorter than in non-REM stage 3/4. The duration of sleep (c
omparing the results of the first with the second half of the sleep pe
riod time) did not modify the arousal response in stages 2 and 3/4. De
spite short-term sleep fragmentation/deprivation the night before the
study, the arousal response to external inspiratory resistive loading
was brisker during REM than non-REM sleep in the healthy subjects stud
ied. The responses were of the same magnitude as those induced in prio
r studies without pretest sleep disturbance. This is different from wh
at is seen in patients with sleep apnea, where breathing disorders are
worst during REM sleep and sleep fragmentation/deprivation leads to r
apid deterioration of arousal responses to the spontaneously occurring
airway occlusions.