In-laboratory Testing Research Articles

A Radar-Based Opioid Overdose Detection Device for Public Restrooms: Design, Development, and Evaluation Study.

The opioid epidemic is a growing crisis worldwide. While many interventions have been put in place to try to protect people from opioid overdoses, they typically rely on the person to take initiative in protecting themselves, requiring forethought, preparation, and action. Respiratory depression or arrest is the mechanism by which opioid overdoses become fatal, but it can be reversed with the timely administration of naloxone. In this study, we described the development and validation of an opioid overdose detection radar (ODR), specifically designed for use in public restroom stalls. In-laboratory testing was conducted to validate the noncontact, privacy-preserving device against a respiration belt and to determine the accuracy and reliability of the device. We used an ODR system with a high-frequency pulsed coherent radar sensor and a Raspberry Pi (Raspberry Pi Ltd), combining advanced technology with a compact and cost-effective setup to monitor respiration and detect opioid overdoses. To determine the optimal position for the ODR within the confined space of a restroom stall, iterative testing was conducted, considering the radar's bounded capture area and the limitations imposed by the stall's dimensions and layout. By adjusting the orientation of the ODR, we were able to identify the most effective placement where the device reliably tracked respiration in a number of expected positions. Experiments used a mock restroom stall setup that adhered to building code regulations, creating a controlled environment while maintaining the authenticity of a public restroom stall. By simulating different body positions commonly associated with opioid overdoses, the ODR's ability to accurately track respiration in various scenarios was assessed. To determine the accuracy of the ODR, testing was performed using a respiration belt as a reference. The radar measurements were compared with those obtained from the belt in experiments where participants were seated upright and slumped over. The results demonstrated favorable agreement between the radar and belt measurements, with an overall mean error in respiration cycle duration of 0.0072 (SD 0.54) seconds for all recorded respiration cycles (N=204). During the simulated overdose experiments where participants were slumped over, the ODR successfully tracked respiration with a mean period difference of 0.0091 (SD 0.62) seconds compared with the reference data. The findings suggest that the ODR has the potential to detect significant deviations in respiration patterns that may indicate an opioid overdose event. The success of the ODR in these experiments indicates the device should be further developed and implemented to enhance safety and emergency response measures in public restrooms. However, additional validation is required for unhealthy opioid-influenced respiratory patterns to guarantee the ODR's effectiveness in real-world overdose situations.

Sleep Medicine Health-Care Worker Concerns About COVID-19: An Early Pandemic Survey.

The coronavirus disease 2019 (COVID-19) pandemic has produced numerous safety concerns for sleep medicine patients and health-care workers, especially related to the use of aerosol-generating positive airway pressure devices. Differences between physician and sleep technologist concerns with regard to viral exposure and mitigation strategies may inform protocols to ensure safety and promote patient and health-care worker resilience and retention. An anonymous online survey aimed at sleep medicine practitioners was active from April 29, 2020 to May 8, 2020. We obtained 379 responses, including from 75 physicians and 283 technologists. The proportion of all the respondents who were extremely/very concerned about the following: exposing patients (70.8%), exposing technologists (81.7%), and droplet (82.7%) and airborne (81.6%) transmission from CPAP. The proportion of respondents who felt that aerosol precautions were extremely/very important varied by scenario: always needed (45.6%); only with CPAP (25.9%); and needed, despite negative viral testing (67.0%). More technologists versus physicians rated the following as extremely/very important: testing parents for COVID-19 (71.2 vs 47.5%; P = .01), high-efficiency particulate air filters (75.1 vs 61.8%; P = .02), and extremely/very concerned about shared-ventilation systems (65.9 vs 51.5%; shared ventilation P = .041). The respondents in northeastern and western United States were more concerned about the availability of COVID-19 testing than were those in other regions of the United States. Among the total number of respondents, 68.0% expected a ≥ 50% drop in patients willing to have in-laboratory testing, with greatest drops anticipated in northeastern United States. Sleep health-care workers reported high levels of concern about exposure to COVID-19. Physicians and technologists generally showed high concordance with regard to the need for mitigation strategies, but the respondents differed widely with regard to which strategies were necessary.

A protocol for mitigating safety events in a sleep laboratory.

Polysomnography is a common outpatient procedure and the rate of adverse events is considered low. Due to the emergence and use of home sleep apnea testing, the patient population presenting for in-laboratory testing may have greater medical complexity, suggesting greater risk for in-laboratory adverse events. We believe that there is a greater need for standardized protocols to triage medically vulnerable populations and for formalized training of sleep technicians to respond to safety events. The sleep laboratories affiliated with the Beth Israel Deaconess Medical Center system developed a referral triage protocol for patients undergoing polysomnography and a training protocol for sleep technicians with a formalized response to medical incidents. Safety events occurring from January 2016 to January 2020 were documented and patient demographics, referral characteristics, event characteristics, and outcomes were analyzed. Sixty-five safety events occurred over this period, with a rate of 1:147 studies. The most common events were chest pain (20/65, 31%), shortness of breath (13/65, 20%), and vital sign abnormalities (12/65, 18%). Patients experiencing events were 49% (32/65) female, with a median age of 57 years (range, 19-91 years); 60 of 65 (92%) had documented medical comorbidities, with a median of 3 documented medical or psychiatric comorbidities (range, 0-9). With the formalized response protocol, the time from incident identification to activation of the appropriate response was a median of 3 minutes (range, 0-47 minutes). The incidence of in-laboratory safety events may be greater than previously described due to the widespread use of home sleep apnea testing. Implementation of formalized response protocols and sleep technician training may be necessary to meet the needs of an increasingly medically complex population.

Impact of the COVID-19 pandemic on obstructive sleep apnea: recommendations for symptom management

In the context of the current COVID-19 pandemic situation, we address the following important questions: (1) How can patients be identified for possible OSA while sleep clinic testing is temporarily unavailable or limited? and (2) What measures can be suggested to improve sleep health until proper diagnosis and treatment become safe and available again? As a proxy for home or in-laboratory testing, validation of a symptom-based measure of OSA risk is presented, based on an ongoing larger prospective study of 156 family medicine patients with OSA (88 women, 68 men; mean age, 57 years) and 60 control participants (36 women, 24 men; mean age, 54 years) recruited from the community. Participants completed the Sleep Symptom Checklist (SSC) and a range of other self-report measures; primary care patients also underwent a polysomnographic sleep study. Results showed that (1) individuals with OSA reported more symptoms on the SSC related to insomnia, daytime symptoms, sleep disorders, and psychological maladjustment than did the control group (all P < .001), and (2) their sleep-related symptoms were significantly more severe than those of the control patients. In addition, several polysomnographic indices in recently diagnosed untreated individuals with OSA were significantly correlated with SSC measured sleep disorder symptoms, and SSC scores significantly distinguished participants with OSA from control participants. Our findings suggest that family practitioners can effectively prescreen patients for possible OSA by inquiring about 5 items that form the SSC sleep disorders subscale. If OSA is suspected, then we can recommend a range of behavioral techniques to improve symptoms. The current pandemic causes us to reflect that the provisional targeting of symptoms and guidance regarding mitigation strategies while waiting for specialist care could serve patients well at any time.

The impact of the COVID-19 pandemic on sleep medicine practices.

The COVID-19 pandemic required sleep centers to consider and implement infection control strategies to mitigate viral transmission to patients and staff. Our aim was to assess measures taken by sleep centers due to the COVID-19 pandemic and plans surrounding reinstatement of sleep services. We distributed an anonymous online survey to health care providers in sleep medicine on April 29, 2020. From responders, we identified a subset of unique centers by region and demographic variables. We obtained 379 individual responses, which represented 297 unique centers. A total of 93.6% of unique centers reported stopping all or nearly all sleep testing of at least one type, without significant differences between adult and pediatric labs, geographic region, or surrounding population density. By contrast, a greater proportion of respondents continued home sleep apnea testing services. A total of 60.3% reduced home sleep apnea testing volume by at least 90%, compared to 90.4% that reduced in-laboratory testing by at least 90%. Respondents acknowledged that they implemented a wide variety of mitigation strategies. While no respondents reported virtual visits to be ≥ 25% of clinical visits prior to the pandemic, more than half (51.9%) anticipated maintaining ≥ 25% virtual visits after the pandemic. Among surveyed sleep centers, the vast majority reported near-cessation of in-laboratory sleep studies, while a smaller proportion reported reductions in home sleep apnea tests. A large increase in the use of telemedicine was reported, with the majority of respondents expecting the use of telehealth to endure in the future.

The impact of structured sleep schedules prior to an in-laboratory study: Individual differences in sleep and circadian timing.

IntroductionMany sleep and circadian studies require participants to adhere to structured sleep-wake schedules designed to stabilize sleep outcomes and circadian phase prior to in-laboratory testing. The effectiveness of this approach has not been rigorously evaluated, however. We therefore investigated the differences between participants’ unstructured and structured sleep over a three-week interval.MethodsTwenty-three healthy young adults completed three weeks of sleep monitoring, including one week of unstructured sleep and two weeks of structured sleep with consistent bed and wake times. Circadian phase was assessed via salivary dim light melatonin onset (DLMO) during both the unstructured and structured sleep episodes.ResultsCompared to their unstructured sleep schedule, participants’ bed- and wake times were significantly earlier in their structured sleep, by 34 ± 44 mins (M ± SD) and 44 ± 41 mins, respectively. During structured sleep, circadian phase was earlier in 65% of participants (40 ± 32 mins) and was later in 35% (41 ± 25 mins) compared to unstructured sleep but did not change at the group level. While structured sleep reduced night-to-night variability in sleep timing and sleep duration, and improved the alignment (phase angle) between sleep onset and circadian phase in the most poorly aligned individuals (DLMO < 1h or > 3h before sleep onset time; 25% of our sample), sleep duration and quality were unchanged.ConclusionOur results show adherence to a structured sleep schedule results in more regular sleep timing, and improved alignment between sleep and circadian timing for those individuals who previously had poorer alignment. Our findings support the use of structured sleep schedules prior to in-laboratory sleep and circadian studies to stabilize sleep and circadian timing in healthy volunteers.

A Personalized Physical Activity Coaching App for Breast Cancer Survivors: Design Process and Early Prototype Testing.

BackgroundExisting evidence supports the many benefits of physical activity (PA) in breast cancer survival. However, few breast cancer survivors adhere to the recommended levels of activity. A PA coaching app that provides personalized feedback, guidance, and motivation to the user might have the potential to engage these individuals in a more active lifestyle, in line with the general recommendations. To develop a successful tool, it is important to involve the end users in the design process and to make theoretically grounded design decisions.ObjectiveThis study aimed to execute the design process and early prototype evaluation of a personalized PA coaching app for posttreatment breast cancer survivors. In particular, the study explored a design combining behavioral theory and tailored coaching strategies.MethodsThe design process was led by a multidisciplinary team, including technical and health professionals, and involved input from a total of 22 survivors. The process comprised 3 stages. In stage 1, the literature was reviewed and 14 patients were interviewed to understand the needs and considerations of the target population toward PA apps. In stage 2, the global use case for the tool was defined, the features were ideated and refined based on theory, and a digital interactive prototype was created. In stage 3, the prototype went through usability testing with 8 patients and was subjected to quality and behavior change potential evaluations by 2 human-computer interaction experts.ResultsThe design process has led to the conceptualization of a personalized coaching app for walking activities that addresses the needs of breast cancer survivors. The main features of the tool include a training plan and schedule, adaptive goal setting, real-time feedback and motivation during walking sessions, activity status through the day, activity history, weekly summary reports, and activity challenges. The system was designed to measure users’ cadence during walking, use this measure to infer their training zone, and provide real-time coaching to control the intensity of the walking sessions. The outcomes from user testing and expert evaluation of the digital prototype were very positive, with scores from the system usability scale, mobile app rating scale, and app behavior change scale of 95 out of 100, 4.6 out of 5, and 15 out of 21, respectively.ConclusionsImplementing a user-centered design approach for the development and early evaluation of an app brings essential considerations to tailor the solution to the user’s needs and context. In addition, informing the design on behavioral and tailored coaching theories supports the conceptualization of the PA coaching system. This is critical for optimizing the usability, acceptability, and long-term effectiveness of the tool. After successful early in-laboratory testing, the app will be developed and evaluated in a pilot study in a real-world setting.

Point-of-Care Testing vs. Laboratory Testing during High Patient Volume Situations

Introduction: Our aim was to determine what patient volume, if any, in-laboratory testing provides results faster than Point-of-Care-Testing (POCT). Methods: To evaluate POCT effectiveness during high volume situations, POCT was compared to in-laboratory testing during busy periods with large numbers of patients. Our setting was an urban level 1 trauma center with an academic emergency medicine department (ED) and annual patient volume of 70,000. Patients seen requiring laboratory testing during peak volume between 11 a.m. and 7 p.m. were enrolled over a five-week period. One tube of blood was sent to the laboratory and the other tube was run in the ED using POCT. Turnaround time was recorded as time from when the tube was received to when the result was available. We also completed a time-motion study to assess the number of POCT machines that would be needed to process the entire average hourly hospital laboratory volume. Results: We collected 539 hematology and chemistry specimens. The POCT group was significantly faster than in-laboratory testing, with mean POCT [complete blood count (CBC) and chemistry] 3.5 minutes compared to in-laboratory CBC test time of 30.9 minutes and chemistry test time of 55 minutes. As the volume of samples peaked, there was a slight but insignificant decrease in POCT turnaround time. If POCT was used to process the entire average hospital laboratory volume which approached 54 samples an hour, 3 POCT machines would be necessary to maintain turnaround times. Conclusion: Even during ED high volume situations, POCT provided results significantly faster than in-laboratory testing.

Portable Monitoring for Diagnosis of Sleep Apnea

Economic and access issues are driving the use of portable monitoring for primary diagnosis of obstructive sleep apnea (OSA) in selected adults. Its applicability has been demonstrated for adults at high risk of sleep apnea, but many caveats and research questions remain. For technical reasons, most limited-channel diagnostic devices tend to underestimate the severity of the disease. In addition, portable monitoring is of little value for sleep disorders other than OSA and has not been advocated for children or the elderly. Similarly, auto-continuous positive airway pressure (APAP) is an alternative to in-laboratory continuous PAP titration. The cost-effectiveness of portable diagnostic testing and APAP titration in actual practice is yet to be determined, but will be a critical question in the years ahead. Future research should examine their use for extended populations, and the economic effect of these modalities, to determine the best use of these techniques as alternatives to traditional in-laboratory testing.

Noninferiority of Functional Outcome in Ambulatory Management of Obstructive Sleep Apnea

Home portable monitor testing is increasingly being used to diagnose patients with obstructive sleep apnea (OSA) and to initiate them on continuous positive airway pressure (CPAP) treatment. To compare functional outcome and treatment adherence in patients who receive ambulatory versus in-laboratory testing for OSA. Veterans with suspected OSA were randomized to either home testing or standard in-laboratory testing. Home testing consisted of a type 3 portable monitor recording followed by at least three nights using an automatically adjusting positive airway pressure apparatus. Participants diagnosed with OSA were treated with CPAP for 3 months. We measured the change in Functional Outcomes of Sleep Questionnaire score, with an a priori noninferiority delta of -1, and the mean daily hours of objectively measured CPAP adherence, with an a priori noninferiority delta of -0.75 hour/day. Of the 296 subjects enrolled, 260 (88%) were diagnosed with OSA, and 213 (75%) were initiated on CPAP. Mean ± SD functional outcome score improved 1.74 ± 2.81 in the home group (P < 0.001) and 1.85 ± 2.46 in the in-laboratory group (P < 0.0001). The lower bound of the one-sided 95% noninferiority confidence interval was -0.54. Mean ± SD hours of daily CPAP adherence were 3.5 ± 2.5 hours/day in the home group and 2.9 ± 2.3 hours/day in the in-laboratory group (P = 0.08). The lower bound of the one-sided 95% noninferiority confidence interval was 0.03. Functional outcome and treatment adherence in patients evaluated according to a home testing algorithm is not clinically inferior to that in patients receiving standard in-laboratory polysomnography.

Development of a Heavy-Duty Engine Test Cycle Representative of On-Highway Not-To-Exceed Operation

This paper describes the development of an engine test cycle that is representative of the real-world heavy-duty engine activity in the not-to-exceed (NTE) zone of operation. The test cycle is intended to provide an in-laboratory verification capability to determine if an engine exceeds the in-use emissions standards. By simulating the real-world driving pattern of the vehicle the test cycles provide the most realistic estimation of emission levels in the NTE zone of operation. It is well recognized that traditional laboratory test cycles do not provide an accurate representation of a vehicle's operation on the road under present-day driving conditions. This cycle was developed by collecting and analysing engine activity data and statistical information on heavy-duty vehicle use for different applications under real-world conditions. A test vehicle instrumented with the West Virginia University mobile emissions measurement system (MEMS), a portable on-board tailpipe exhaust emissions measurement system, was used to obtain engine operating conditions, vehicle speed, and in-use brake-specific emissions of CO2 and NO x. The vehicle was tested on specific routes, which included a mix of highway and city driving patterns. The speed and torque points were normalized according to procedures described in the Code of Federal Regulations (CFR) Title 40, Part 1065. A representative transient cycle that was developed has been used to conduct emissions tests on heavy-duty diesel engines, and serves to characterize NO x emissions during the NTE operation. This characterization will aid in-laboratory testing and provide a better understanding of the emissions behaviour during on-road NTE operation, electronic control module calibrations, and engine development. The results indicate that the on-highway NTE cycle called the ‘WVU NTE cycle’ produced emissions results that were within ±1 per cent of those produced during an on-road test.

Perceptual training improves syllable identification in new and experienced hearing aid users

We assessed the effects of perceptual training of syllable identification in noise on nonsense syllable test (NST) performance of new (Experiment 1) and experienced (Experiment 2) hearing aid (HA) users with sensorineural hearing loss. In Experiment 1, new HA users were randomly assigned to either immediate training (IT) or delayed training (DT) groups. IT subjects underwent 8 weeks of at-home syllable identification training and in-laboratory testing, whereas DT subjects underwent identical in-laboratory testing without training. Training produced large improvements in syllable identification in IT subjects, whereas spontaneous improvement was minimal in DT subjects. DT subjects then underwent training and showed performance improvements comparable with those of the IT group. Training-related improvement in NST scores significantly exceeded improvements due to amplification. In Experiment 2, experienced HA users received identical training and testing procedures as users in Experiment 1. The experienced users also showed significant training benefit. Training-related improvements generalized to untrained voices and were maintained on retention tests. Perceptual training appears to be a promising tool for improving speech perception in new and experienced HA users.