P003 The impact of forced wake from overnight polysomnography on multiple sleep latency test results

Introduction The multiple sleep latency test (MSLT) is used to diagnose disorders of hypersomnolence. Although internationally-recognised protocols do not stipulate whether patients should be woken from the preceding overnight polysomnography (PSG), many labs wake their patients for logistic reasons. This study analyses the impact on PSG and MSLT parameters of forced wake (FW) from the overnight PSG compared with unrestricted sleep (US). Methods 400 consecutive patients (FW=200; US=200) undergoing PSG/MSLT were included and the following parameters were compared: Epworth Sleepiness Scale (ESS), Morningness-Eveningness Questionnaire score (MEQ), PSG total sleep time (TST), wake-up time from the PSG, overall MSLT sleep latency (MSL), individual nap latencies (SLNap 1–4), number of MSLT naps with sleep-onset REM periods (#SOREMP), and percentage of MSLTs with overall MSL<8 minutes (%MSLT<8). Results The 2 groups were well-matched for ESS and MEQ. The FW group had more males (49% vs 39%). When compared to FW, patients with US had longer TST (+38 minutes; p=<0.0001), later wake-up time (+52 minutes; p<0.0001), longer MSL (+1.9 minutes; p=0.0049), 50% fewer #SOREMP (p=0.0224), and 16% fewer %MSLT<8 (p=0.0018). SLNap1 increased by 1.5 minutes (p=0.0623), SLNap2 increased by 2.0 minutes (p=0.0067), SLNap3 increased by 0.75minutes (p=0.0533) and SLNap4 increased by 2.5 minutes (p=0.0059). Discussion Allowing patients to have unrestricted sleep on the night prior to the MSLT resulted in significantly longer TST, longer sleep latencies during the MSLT, fewer SOREMP and fewer tests with MSL<8 minutes. International protocols should stipulate unrestricted sleep on the PSG prior to the MSLT to improve diagnostic accuracy.

P166 Measures of overnight sleep stability in patients with hypersomnolence

Introduction Hypersomnolence causes significant impairment of daytime functioning. The multiple sleep latency test (MSLT) measures objective hypersomnolence (OH). Patients with hypersomnolence with a normal MSLT are said to have subjective hypersomnolence (SH). The mechanisms of hypersomnolence in such patients is uncertain. This study describes differences in measures of sleep stability derived from the overnight polysomnography (PSG) in patients with OH and SH. Methods A retrospective analysis of 100 patients undergoing PSG/MSLT for investigation of hypersomnolence was performed. Patients were classified as OH (MSLT≤8 min) or SH (MSLT>8min). Sleep stage distribution and PSG-derived markers of sleep stability including cardiopulmonary coupling (CPC), cyclic alternating pattern (CAP) and sleep stage shifts were compared between the two groups. Results When compared to OH patients (N=50), SH patients (N=50) had significantly more sleep stage shifts, more shifts to stage N1 and longer PSG sleep latency. Small but significantly lower sleep efficiency, higher stage N1 and N3 proportions were also observed in SH patients. OH patients had a small but significantly higher CAP rate and CAP index compared to SH patients. There were no significant differences in CPC metrics between the two groups. Conclusion Several PSG-derived markers of sleep stability indicated that patients with SH experienced more unstable sleep than OH patients. This may provide insight into the underlying pathophysiological mechanisms which differentiate these patient groups and may serve as a future therapeutic target.

Late-Onset Narcolepsy: A Case Report with Brief Review of the Literature

Narcolepsy, a sleep disorder, has its onset in childhood and early adulthood but rarely in older adults. This case report focuses on a man in his late fifties who was noticed to have excessive daytime sleepiness during his stay in our hospital for an unrelated medical ailment. He was further evaluated with overnight polysomnography and next day multiple sleep latency test which confirmed the diagnosis of narcolepsy.

1207 Keep It Simple: Wireless Patches For Home Sleep Diagnostics

Introduction Despite growing use of home sleep testing for the diagnosis of obstructive sleep apnea (OSA), there are significant barriers including limited availability, high cost, and complex wires making it difficult for patients to use on their own. The objective of this study was to evaluate a new flexible, thin, and wireless adhesive patch (proprietor sensors, TatchSleep Pro [TSP]) for the detection of OSA and compare the validity to overnight polysomnography (PSG). The TSP transmits data wirelessly to a smartphone app which in turn uploads the data to a cloud server. Data is presented to a sleep professional via a dedicated interface to score and analyze the results. Methods Patients (n=9; mean age=47 (SD=10); mean BMI=33 (SD=6.6); 4 males) undergoing a PSG evaluation for OSA also wore 2 TSP patches applied on the chest and abdomen. The TSP patches detected respiratory effort, derived airflow, derived pressure, body position and movement. Two sets of respiratory data (with common SpO2 and heartrate as a reference from PSG) were created, one from PSG and one from the TSP. The data were then scored by a certified sleep technician, blinded to the conditions. Linear regression analyses were used to compare the two derived apnea-hypopnea indices (AHI). In the morning, all participants were asked about their experience using the TSP. The study was approved by the Western IRB. Results There was a significant correlation for AHI between the TSP and PSG (R2= 0.94; p<0.01). All participants found the TSP comfortable to wear and indicated that removing the patches was ‘easy’ or ‘very easy,’ Conclusion These preliminary results suggest the wireless TSP may be an effective, cost-efficient way to evaluate OSA. Despite small sample, results show promise as a new innovative product for home sleep testing. Support Supported by Tatch Inc.

Our Baby Can’t Eat, Can’t Breathe, and Can’t Sleep!

An infant with severe congenital laryngomalacia presented with inspiratory stridor when feeding, crying, or supine, relieved by prone or upright repositioning. Suprasternal retractions, hypoxemia, feeding difficulties, and failure to thrive prompted admission to the pediatric intensive care unit. Symptoms of sleep disordered breathing contributed to the severity of her laryngomalacia. Overnight polysomnography confirmed severe obstructive sleep apnea and sleep-related hypoxemia. The patient underwent supraglottoplasty with resolution of the wake hypoxemia but with residual stridor and apnea. Revision supraglottoplasty led to remission of the stridor and obstructive sleep apnea but emergence of central sleep apnea. This case discusses the clinical features, diagnostic evaluation, and management of congenital laryngomalacia. Supraglottoplasty, reserved for infants with moderate or severe laryngomalacia, is the treatment of choice. Obstructive sleep apnea improves but usually does not fully remit after supraglottoplasty. Central sleep apnea is not uncommon in infants with laryngomalacia and may reflect immature or abnormal brainstem nuclei regulating regulation of respiration during sleep.