SLEEP 2011 Abstract Supplement

B. Clinical Sleep Science I. Sleep Disorders – Breathing
able, non-invasive, and low-cost, this algorithm has the potential for
SDB screening in both hospital and home care environments.
0381
FEASIBILITY OF DETECTION OF PERIODIC BREATHING
USING RESPIRATORY SINUS ARRHYTHMIA PATTERNS
FROM SLEEP TIME AMBULATORY ECG RECORDINGS
Stein PK 1 , Redline S 2
1
Cardiovascular Division, Washington University School of Medicine,
St. Louis, MO, USA, 2 Department of Medicine and Division of Sleep
Medicine, Harvard Medical School, Boston, MA, USA
Introduction: Respiratory sinus arrhythmia (RSA), the response of
the heart rate to autonomic changes during respiration, clearly tracks
respiratory rate. RSA is especially prominent when subjects are supine.
Periodic respiration is associated with a waxing and waning of the respiratory
rate that should, in theory, be reflected in RSA and visible from a
plot of instantaneous heart rate vs. time (HR tachogram).
Methods: HR tachograms from the ECG channel of recordings from
older adults in the Sleep Heart Health Study were examined. ECGs had
been extracted and scanned to research standards on a MARS PC Holter
system. (GE Medical Systems, Milwaukee, WI). N=23 participants were
selected as having been identified by the technician as having periodic
breathing (PERGP) and also as having a central sleep apnea (>1/hr).
These were matched by age and gender with participants without periodic
breathing or central sleep apnea (NOGP). The presence of periodic
breathing was blindly scored from HR tachograms. Participants were
categorized as definite, possible or no periodic breathing based on the
presence of RSA patterns suggesting cycles of increasing and decreasing
respiratory rates. When discrepancies between SHHS and visual scoring
occurred, the respiratory channels of the PSG were examined.
Results: Results: There were 38 interpretable recordings (9F,31M, age
78 SD 4 yrs). Of the 20 usable recordings in the NOGP, 3 were categorized
as definite, 3 as possible and 14 as no periodic breathing. After
examination of the PSGs, one of the 3 categorized as definite periodic
breathing did have it, one had missing respiratory data at the time of the
periodic RSA on ECG and one had respiration that was periodic in amplitude
but not frequency. Of the 3 scored as possible, one had periodic
amplitude but not frequency patterns, one had an abnormal heart rate
pattern and one did not have any periodic breathing. N=16 of 18 usable
recordings in the PERGP were categorized as having definite periodic
breathing, one as possible and one as no. After examination of the PSGs,
it was determined that the PER subject classified as no, had the wrong
ECG file and the PSG ECG file for that person was not available.
Conclusion: Significant periodic respiration is clearly identifiable from
RSA patterns on heart rate tachograms, suggesting that screening for this
breathing pattern could be included in the information available from
routine ambulatory ECG recordings.
Support (If Any): 2RO1HL062181-09
0382
DELAYED CIRCADIAN PHASE AND THE TIMING OF THE
POLYSOMNOGRAM TO DIAGNOSE OBSTRUCTIVE SLEEP
APNEA
Ubaissi H, Jain V, Gutierrez G, Shan K
Pulmonary, Critical Care and Sleep Medicine, George Washington
University, Washington, DC, USA
Introduction: False negative polysomnograms could adversely affect
the diagnosis and management of patients with obstructive sleep apnea
(OSA). We hypothesize that false negative polysomnograms could occur
from discordance between the patient’s circadian phase and the routine
sleep laboratory schedule.
Methods: Prospective study of seven patients with delayed circadian
phase and high clinical suspicion for OSA. Patients were included if the
first diagnostic polysomnogram, done according to the sleep laboratory
timing, was negative for OSA. These patients subsequently underwent
a second polysomnogram performed in accordance with the patient’s
circadian phase. We evaluated differences between the two polysomnograms
with respect to apnea hypopnea index (AHI), total sleep time
(TST) and time spent in REM sleep. Data were analyzed with paired t
test, P < 0.05 was considered statistically significant. Mean ± SD.
Results: There were statistically significant increases in all endpoints
between the first and second polysomnograms. AHI and time spent in
REM increased for all seven patients, while TST increased in six patients.
AHI increased from 4.4 ± 1.7 events/hour to 14.3 ± 5.4 events/
hour (P