Elucidation of obstructive sleep apnoea related blood pressure surge using a novel continuous beat-to-beat blood pressure monitoring system

Abstract

Background: Obstructive sleep apnoea (OSA) episode related blood pressure (BP) surge may mediate the association of OSA with cardiovascular disease. However, BP is not measured during a clinical sleep study. Method:We tested the feasibility of incorporating the Caretaker physiological monitor, which utilizes a novel continuous beat-to-beat (b-b) BP monitoring technology, into polysomnography (PSG) and aimed to characterize BP surges related to obstructive respiratory events. B-b BP was concurrently collected and merged with PSG data on a posthoc basis. We compared BP surge between mean respiratory (apnoea, hypopnea and desaturation-alone events) and nonrespiratory events (spontaneous or leg movement-related arousals). We examined the association of the degree of oxygen desaturation with BP surge in a given respiratory event combining all events. A total of 17 consecutive patients (12 men, mean 52 years old, nine diagnostic and eight split-night PSGs) undergoing clinically indicated PSG were included after excluding one patient with poor signal quality due to excessive movement.Results: Caretaker was well tolerated. Mean respiratory BP surge ranged from 5 to 19 mmHg [Median (IQR) ¼ 13.9 (9.5-16.2)]. Mean BP surge between the respiratory and nonrespiratory events was similar [13.8 (4.5) vs. 14.9 (5.3) mmHg, P ¼ 0.13]. Accounting for the count distribution of desaturation/BP surge data pair events, there was a linear correlation between the degree of oxygen desaturation and BP surge (R ¼ 0.57, P < 0.001). In eight patients undergoing split-night sleep studies, the number of BP surge events (10 mmHg/h) decreased during continuous positive airway pressure in all but one patient. Conclusion:We demonstrated highly variable OSA-related BP surge patterns using the Caretaker's b-b BP monitoring technology that has the potential to be integrated into sleep studies.

Development of beat-by-beat blood pressure monitoring device and nocturnal sec-surge detection algorithm

“…No significant differences were observed in the severity of sec-surges between SA-related and non-SA-related sec-surges (number of sec-surges: 19.5 ± 26.0 vs. 16.4 ± 29.8 events, peak: 148.2 ± 18.5 vs. 149.3 ± 19.2 mmHg, amplitude: 26.0 ± 4.3 vs. 25.8 ± 5.7 mmHg, arranged according to SA factor and non-SA factor) [ 31 ]. Our findings align with prior research, which found no significant differences between SA-related and non-SA-related BP elevation as assessed by the PTT method [ 46 ].…”

“…Previous studies [ 46 , 47 ] have evaluated SA-related BPV using the PTT method or pulse decomposition analysis (PDA) in patients with OSA or suspected OSA. Their SA-related BPV, nearly equal to sec-surge, was smaller than in our study.…”