-
[show abstract]
[hide abstract]
ABSTRACT: Single-channel ECG and linger photoplethysmogram were used to estimate sleep states in obstructive sleep apnea patients. Overnight Holter-oximeter recordings from 14 subjects with suspected sleep apnea were analysed. Parameters including the RR interval, photoplethysmogram amplitude and rise time, and pulse arrival time were characterised and a hidden Markov model classifier used to identify wake, REM and sleep states. An overall accuracy of 77% and Cohen's kappa of 0.54 was achieved, establishing a baseline level of usefulness for sleep state estimation using a Holter-oximeter. Autonomic arousals detected using pulse arrival time also appeared to be strongly correlated with Epworth Sleepiness Scale scores.
Engineering in Medicine and Biology Society, 2007. EMBS 2007. 29th Annual International Conference of the IEEE; 09/2007
-
[show abstract]
[hide abstract]
ABSTRACT: Single-channel ECG and finger photoplethysmogram were used to estimate sleep states in obstructive sleep apnea patients. Overnight Holter-oximeter recordings from 14 subjects with suspected sleep apnea were analysed. Parameters including the RR interval, photoplethysmogram amplitude and rise time, and pulse arrival time were characterised and a Hidden Markov Model classifier used to identify Wake, REM and Sleep states. An overall accuracy of 77% and Cohen's kappa of 0.54 was achieved, establishing a baseline level of usefulness for sleep state estimation using a Holter-oximeter. Autonomic arousals detected using pulse arrival time also appeared to be strongly correlated with Epworth Sleepiness Scale scores.
Conference proceedings: ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Conference 02/2007; 2007:3998-4001.
-
[show abstract]
[hide abstract]
ABSTRACT: The cardiopulmonary coupling measure has been proposed recently as an indicator of sleep stability. We examined changes in cardiopulmonary coupling during the sleep onset period and its usefulness in estimating sleep onset. Overnight polysomnography data from 10 male adults without sleep disordered breathing was analysed (age 40 plusmn 7 years, BMI 31 plusmn 3 kg/m<sup>2</sup>, AHI 0.9 plusmn 0.9 hr<sup>-1</sup>). Results suggest that cardiopulmonary coupling typical of unstable sleep was associated with phases of wakefulness and awakening. Sleep onset latency was estimated with an average error of 9 mins. In conclusion, cardiopulmonary coupling is able to provide statistical trends with respect to the sleep onset period, and is also useful in pinpointing sleep onset.
Biomedical and Pharmaceutical Engineering, 2006. ICBPE 2006. International Conference on; 01/2007
-
[show abstract]
[hide abstract]
ABSTRACT: Pulse arrival time and the amplitude of the finger photoplethysmogram were used to track blood pressure continuously over 10-minute intervals. The measures were recorded with a holter-oximeter from a sample of 8 young, healthy human subjects in the supine and standing positions. Results indicate that, with individual calibration, systolic and diastolic blood pressure can be estimated with an average error of plusmn6 and plusmn4 mmHg respectively. Using pulse arrival time in combination with the amplitude of the finger photoplethysmogram gave better results than using any one alone, with PPG amplitude appearing to be more robust
Engineering in Medicine and Biology Society, 2006. EMBS '06. 28th Annual International Conference of the IEEE; 10/2006
-
[show abstract]
[hide abstract]
ABSTRACT: Pulse arrival time and the amplitude of the finger photoplethysmogram were used to track continuous systolic blood pressure over 10-minute intervals. The measures were recorded with a holter-oximeter from a sample of 8 young, healthy human subjects in the supine and standing positions. Results show that, with individual calibration, systolic blood pressure can be estimated with an average error of ±5 mmHg. Using pulse arrival time in combination with the amplitude of the finger photoplethysmogram gave better results than using any one alone.
Advances in Medical, Signal and Information Processing, 2006. MEDSIP 2006. IET 3rd International Conference On; 08/2006
-
[show abstract]
[hide abstract]
ABSTRACT: We considered the capability of pulse transit time (PTT) to provide respiratory information in obstructive sleep apnea (OSA) patients. PTT-derived respiratory frequency was quite well correlated with that derived from inductance plethysmography, with amplitude slightly less so. The PTT-derived respiratory estimates were also used to distinguish sleep stage. In some subjects, statistically significant differences in respiratory parameters were observed between wake, REM, and stage 2 sleep, but this effect was highly subject dependent
Engineering in Medicine and Biology Society, 2005. IEEE-EMBS 2005. 27th Annual International Conference of the; 02/2006
-
[show abstract]
[hide abstract]
ABSTRACT: Pulse arrival time and the amplitude of the finger photoplethysmogram were used to track blood pressure continuously over 10-minute intervals. The measures were recorded with a holter-oximeter from a sample of 8 young, healthy human subjects in the supine and standing positions. Results indicate that, with individual calibration, systolic and diastolic blood pressure can be estimated with an average error of +/-6 and +/-4 mmHg respectively. Using pulse arrival time in combination with the amplitude of the finger photoplethysmogram gave better results than using any one alone, with PPG amplitude appearing to be more robust.
Conference proceedings: ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Conference 02/2006; 1:5117-20.
