SLEEP 2011 Abstract Supplement

B. Clinical Sleep Science XIV. Instrumentation and Methodology
BMI, weight, or AHI severity on the sensitivity or specificity of the classifications.
Conclusion: Load cells are capable of differentiating disordered breathing
events from normal respiration without direct patient contact. Further
work is needed to detect events within a continuous collection. This
technology could ultimately provide low cost, contact free monitoring
for respiratory events over many nights in the comfort of a patient’s own
bed.
Support (If Any): This work was funded by NHLBI (1R01HL098621)
and by a grant from Intel Corporation.
0955
RELATIONSHIPS BETWEEN HOME POLYSOMNOGRAPHY
AND WATCH-PAT MEASURES OF SLEEP DISORDERED
BREATHING IN PREGNANCY
O’Brien LM 1,2 , Bullough AS 3 , Hewlett MM 1 , Arastu F 1 , Shelgikar AV 1 ,
Chames M 4 , Chervin RD 1
1
Neurology, University of Michigan, Ann Arbor, MI, USA, 2 Oral
& Maxillofacial Surgery, University of Michigan, Ann Arbor, MI,
USA, 3 Anesthesiology, University of Michigan, Ann Arbor, MI, USA,
4
Obstetrics & Gynecology, University of Michigan, Ann Arbor, MI,
USA
Introduction: Sleep-disordered breathing (SDB) during pregnancy is
associated with adverse pregnancy outcomes. However, full overnight
polysomnographic (PSG) studies are labor-intensive and challenging to
perform in pregnant women, particularly in late gestation. The Watch-
PAT device is a simple, wrist-worn device approved for diagnosis of
SDB. We examined levels of agreement between key variables obtained
from full ambulatory PSG and Watch-PAT in pregnant women.
Methods: Women in their third trimester were recruited from obstetric
clinics to undergo full overnight PSG at home using the MediPalm
system as well as the Watch-PAT200 device. PSGs from the MediPalm
were scored by an experienced technologist using AASM 2007 criteria;
the Watch-PAT was scored automatically with its proprietary software.
Results: A total of 17 pregnant women have been studied. Mean age
was 30.6±6.5 years and mean BMI was 31.0±7.2 kg/m2. Good correlations
were found between the two devices for total sleep time (r=0.91,
p3% desaturation). AutoSet respiratory events were autoscored by the
device and summary statistics were provided within RemLogic. Participants
from a larger trial of CPAP adherence who had a clinical indication
for performing an efficacy study (i.e., either high residual CPAP-measured
AHI or subjective report that was inconsistent with CPAP data)
were included.
Results: Mean CPAP-scored AHI was 15.1±12 (3.9 - 46.3) and mean
manual-scored AHI was 9.9±10.5 (1.2 - 39.3). The main finding was
that CPAP-scored HI was 2.55 times higher on average than the manual-scored
HI. Further, the CPAP-scored AI was 1.2 times higher and
the overall CPAP-scored AHI was 1.9 times higher on average than the
manually scored AI and AHI, respectively.
Conclusion: In this sample, CPAP-scored HI was on average more than
double the manual-scored HI. Given the importance of CPAP efficacy
data in tracking treatment progress, it is important to recognize the possible
bias of CPAP in overreporting hypopneas. The most likely cause of
this discrepancy is the use of desaturations in manual hypopnea scoring.
0957
A NON-ACOUSTIC MODEL OF SLEEP FRAGMENTATION
Dudley KA, Pogach M, Thomas RJ, Kulczewski B, Boucher J, Weiss J
Medicine: Pulmonary, Critical Care, and Sleep, Beth Israel Deaconess
Medical Center, Boston, MA, USA
Introduction: Sleep disordered breathing (SDB) causes recurrent partial
or total airway occlusion, cyclical hypoxia, and sleep fragmentation.
Sleep fragmentation also occurs in insomnia, chronic pain, congestive
heart failure, fibromyalgia, rheumatoid arthritis, depression, malignancy,
and circadian rhythm disturbances. In humans, acoustic or combined
acoustic and sensory stimulation have been used to fragment sleep, models
that are labor intensive and pose potential risks (e.g., auditory injury)
to subjects. We tested a non-acoustic model of sleep fragmentation to assess
efficacy, reproducibility, habituation effects, and autonomic effects.
Methods: A stepwise approach tested the effectiveness of standard noninvasive
blood pressure cuffs (inflating at intervals of 1.5-5 minutes to
determine the most effective interval) as a method of fragmenting sleep
in normal healthy subjects. N = 4 subjects underwent baseline polysomnography
(PSG), followed by 3 nights of non-acoustic fragmentation
with PSG monitoring for protocol optimization. N = 1 completed
psychomotor vigilance testing (PVT) and multiple sleep latency testing
(MSLT) before and after fragmentation (3 nights). N = 2 underwent
muscle sympathetic nerve activity (MSNA), progressive isocapnic hypoxia
(HVR), and measurement of serum catecholamine and cortisol
levels pre- and post-fragmentation (3 nights).
Results: In all subjects, our model consistently produced delta EEG
bursts, suggesting reproducibility without habituation. EEG bursts correlated
with blood pressure cuff inflation, as well as autonomic effects
with increased heart rate and absence of nocturnal blood pressure dipping.
The degree and length of fragmentation in our study population did
not impact vigilance or result in daytime sleepiness (MSLT).
Conclusion: Our sleep fragmentation model may be a practical, reliable,
and reproducible method to study the effects of sleep fragmentation. We
propose that adaptive mechanisms which prevent effects on vigilance
and daytime hypersomnia lead to changes in sympathetic activity, resulting
in reversal of nocturnal blood pressure dipping profiles in normal
healthy subjects. Longer durations need testing.
A327
SLEEP, Volume 34, Abstract Supplement, 2011