Non-contact monitoring of agitation and use of a sheltering device in patients with dementia in emergency departments: a feasibility study.

BACKGROUND: Agitation is common in geriatric patients with cognitive impairment, e.g. in persons with dementia (PWD), who are admitted to an emergency department (ED). It might be a first sign of upcoming delirium and is associated with a higher risk of an unfavorable clinical course. Hence, monitoring of vital signs and enhanced movement as indicators of upcoming agitation is essential in these patients during their stay in the ED. Since PWD rarely tolerate fixed monitoring devices, a novel developed non-contact monitoring system (NCMSys) might represent an appropriate alternative. Aim of this feasibility study was to test the validity of a NCMSys and of the tent-like "Charité Dome" (ChD), aimed to shelter PWD from the busy ED environment. Furthermore, effects of the ChD on wellbeing and agitation of PWD were investigated. METHODS: Both devices were attached to patient's bed. Tests on technical validity and safety issues of NCMSys and ChD were performed at the iDoc institute with six healthy volunteers. A feasibility study evaluating the reliability of the NCMSys with and without the ChD was performed in the real-life setting of an ED and on a geriatric-gerontopsychiatric ward. 19 patients were included, ten males and nine females; mean age: 77.4 (55-93) years of which 14 were PWD. PWD inclusion criteria were age ≥ 55 years, a dementia diagnosis and a written consent (by patients or by a custodian). Exclusion criteria were acute life-threatening situations and a missing consent. RESULTS: Measurements of heart rate, changes in movement and sound emissions by the NCMSys were valid, whereas patient movements affected respiratory rate measurements. The ChD did not impact patients' vital signs or movements in our study setting. However, 53% of the PWD (7/13) and most of the patients without dementia (4/5) benefited from its use regarding their agitation and overall wellbeing. CONCLUSIONS: The results of this feasibility study encourage a future controlled clinical trial in geriatric ED patients, including PWD, to further evaluate if our concept of non-contact measurement of vital signs and movement combined with the "Charité Dome" helps to prevent upcoming agitation in this vulnerable patient group in the ED. TRIAL REGISTRATION: ICTRP: "Charité-Dome-Study - DRKS00014737" (retrospectively registered).

Analysis of nocturnal pulse oximetry in sleep medicine.

Oxygen saturation obtained from nocturnal pulse oximetry is a significant evaluation parameter for sleep related breathing disorders, especially in the diagnosis of the obstructive sleep apnea syndrome (OSA). Today clinical interpretation relies mainly on the number of desaturation events per hour (oxygen desaturation index, ODI). In this study various alternatives were established and their applicability for OSA screening was evaluated. The discussed methods include time-based approaches (Δ-index), non-linear analysis (central tendency measure, approximate entropy), and spectral methods (Welch transform, wavelet transform). When applied to 192 data sets (132 male, 60 female, 47.9±15.5 years, BMI 27.4±6.5 kg/m(2)) these methods showed good correlation with clinical findings. When discriminating between non-OSA and OSA patients the approaches under investigation yield sensitivity values between 96.6% and 100% and specificity values between 97.4% and 100%. Particularly spectral methods could provide parameters for an optimized OSA screening based on nocturnal pulse oximetry.

Sensitivity and specificity of telemedicine-based long-term pulse-oximetry in comparison with cardiorespiratory polygraphy and polysomnography in patients with obstructive sleep apnoea syndrome.

We investigated the feasibility of night-time pulse-oximetry telemedicine. We compared polysomnography (PSG) as the gold standard with simultaneously recorded pulse-oximetry from a wrist pulse-oximeter. The results were evaluated by a sleep specialist and compared with outpatient polygraphy. A total of 135 consecutive patients (mean age 55 years, mean body mass index 31.6 kg/m(2)) were studied. Patients with minor, moderate and severe PSG findings were grouped together and compared to those without PSG findings; the resulting sensitivity was 1 and specificity 0.35. In addition, patients with and without minor PSG findings were grouped together and compared to those with moderate and severe PSG findings; the resulting sensitivity was 0.66 and the specificity was 0.98. The receiver operating characteristic (ROC) of telemedically-evaluated oximetry was superior to that of outpatient polygraphy. In contrast, the automatic assessment of severity based on the Oxygen Desaturation Index was unsatisfactory. For patients suspected of sleep related breathing disorders (SRBD), telemedically-evaluated pulse-oximetry is able to identify those who should be referred to a sleep laboratory for definitive diagnosis and treatment. The technique appears to be suitable for first screening in all patients at risk for SRBD.