Wireless Pulse Oximeter Research Articles

The effects of virtual reality interventions on occupational participation and distress from symptoms in palliative care patients: A pilot study.

Virtual reality (VR) offers the prospect of a safe and effective adjunct therapeutic modality to promote mental health and reduce distress from symptoms in palliative care patients. Common physiological and psychological symptoms experienced at the end of life may impact the person's participation in day-to-day activities that bring them meaning. The purpose of this study was to examine the effect of VR interventions on occupational participation and distress from symptoms. To describe the stimulus, results, and learnings from a single-site pilot study of virtual reality therapy in a specialist palliative care setting. Participants engaged in a VR session lasting from 9 to 30 minutes related to coping with pain, inner peace and mindfulness, adventure, and bucket list. The pilot prospective quantitative observational cohort study was conducted from November 2021 through March 2022 using a pre-post VR intervention research design. Quantitative data was collected using patient-rated assessments and a wireless pulse oximeter. Occupational performance, satisfaction, and distress symptoms were measured using the Canadian Occupational Performance Measure and the Palliative Care Outcomes Collaboration Symptom Assessment Scale (PCOC SAS). The intervention and study design adhered to international guidelines. Ten participants engaged in the VR interventions. Data showed significantly improved occupational performance and satisfaction scores (p < .001), decreases in PCOC SAS distress from pain (p = .01), fatigue (p < .001), and heart rate (p = .018). No adverse side effects were observed. Outcomes included an analysis of virtual reality's effectiveness to alleviate symptom burden and increase occupational participation for palliative care patients. Of specific interest to the research team was the application of virtual reality in a community-based and inpatient palliative care context to supplement allied health services and its feasibility of integration into standard palliative care. VR therapy showed positive improvements in the participants' occupational performance, satisfaction, and distress from pain and fatigue.

Excessive Oxygen Administration in High-Risk Patients Admitted to Medical and Surgical Wards Monitored by Wireless Pulse Oximeter.

The monitoring of oxygen therapy when patients are admitted to medical and surgical wards could be important because exposure to excessive oxygen administration (EOA) may have fatal consequences. We aimed to investigate the association between EOA, monitored by wireless pulse oximeter, and nonfatal serious adverse events (SAEs) and mortality within 30 days. We included patients in the Capital Region of Copenhagen between 2017 and 2018. Patients were hospitalized due to acute exacerbation of chronic obstructive pulmonary disease (AECOPD) or after major elective abdominal cancer surgery, and all were treated with oxygen supply. Patients were divided into groups by their exposure to EOA: no exposure, exposure for 1-59 min or exposure over 60 min. The primary outcome was SAEs or mortality within 30 days. We retrieved data from 567 patients for a total of 43,833 h, of whom, 63% were not exposed to EOA, 26% had EOA for 1-59 min and 11% had EOA for ≥60 min. Nonfatal SAEs or mortality within 30 days developed in 24%, 12% and 22%, respectively, and the adjusted odds ratio for this was 0.98 (95% CI, 0.96-1.01) for every 10 min. increase in EOA, without any subgroup effects. In conclusion, we did not observe higher frequencies of nonfatal SAEs or mortality within 30 days in patients exposed to excessive oxygen administration.

Accuracy of Wireless Pulse Oximeter on Preterm or

Monitoring heart rate (HR) and oxygen saturation (SpO2) in infants is essential in the neonatal intensive care unit. Wireless pulse oximeter technology has been advancing but with limited accuracy data on preterm infants. This observational study compared HR and SpO2 of the wireless Owlet Smart Sock 3 (OSS3) to the wired Masimo SET (Masimo) pulse oximeter in preterm or <2.5 kg infants. Twenty-eight eligible infants were enrolled. They weighed between 1.7 and 2.5 kg and were without anomalies or medical instability. OSS3 and Masimo simultaneously monitored HR and SpO2 for 60 minutes. The data were aligned by time epoch and filtered for poor tracings. The agreement was compared using the Pearson's correlation coefficient, the Bland-Altman method, average root mean square (ARMS), and prevalence and bias adjusted kappa (PABAK) analyses. Two infants' data were excluded due to motion artifacts or device failures. The corrected gestational age and current weights were 35 ± 3 weeks and 2.0 ± 0.2 kg (mean ± standard deviation), respectively. Over 21 hours of data showed that HR was strongly correlated between the two devices (r = 0.98, p < 0.001), with a difference of -1.3 beats per minute (bpm) and the limit of agreement (LOA) -6.3 to 3.4 bpm based on the Bland-Altman method. SpO2 was positively correlated between the two devices (r = 0.71, p < 0.001) with a SpO2 bias of 0.3% (LOA: -4.6 to 4.5%). The estimated ARMS of OSS3 compared with Masimo was 2.3% for SpO2 in the 70 to 100% range. The precision decreased with lower SpO2. A strong agreement (PABAK = 0.94) was between the two devices on whether SpO2 was above or below 90%. OSS3 provided comparable HR and SpO2 accuracy to Masimo in preterm or <2.5 kg infants. Motion artifacts, lack of arterial blood gas comparisons, and lack of racial and ethnic diversity are the study limitations. More OSS3 data on the Lower HR and SpO2 ranges were needed before implementing inpatient use. · Pulse oximeters are vital for monitoring preterm infants' HR and SpO2 levels.. · Limited data exist on the accuracy of the wireless OSS3 on preterm infants.. · This observational study found that the OSS3 is comparable to the Masimo SET in measuring HR and SpO2 in preterm or <2.5 kg infants..

A Microcontroller Based Pulse Oximeter with Adaptive Algorithm for Non-Invasive COVID-19 Detection

A pulse oximeter is a clip-on device that is used to measure the oxygen saturation of the arterial blood. This measurement of oxygen saturation is very important to the medical practitioners because there are many anomalies that can lead to a drop of oxygen saturation such as suffocation, choking, lung infections (ronchitis, pneumonia and bronchiolitis), COVID-19 and inhalation of poisonous chemicals. With the outbreak of the novel Covid-19 pandemic which has in turn led to a paradigm shift in the way that activities are being carried out in different economies of the world, it has indeed become an imperative to adopt a more pragmatic approach in not only combating the thread of the current pandemic but to also adequately prepare ahead for any other outbreak that may occur in the future. A lot of researchers have adopted the use of traditional pulse oximeter for getting the level of oxygen saturation of the blood via non-invasive means. However, the use of traditional pulse oximeter exposed the medical practitioners to infectious diseases due to proximity problem. Also, discrepancies in the environmental factors, the readings obtained from the device becomes flawed with errors. To solve the aforementioned problem, this work designed a robust wireless pulse oximeter which is a very important device used in the medical field to obtain the level of oxygen saturation and heartbeat of a patient with safe proximity. Performance evaluation of the designed pulse oximeter was carried out using the SpO2 and heart rate as performance metrics. It can be observed that the Root Mean Squire Error (RMSE) values of SpO2 and BPM were found to be 1.549 and 3.233 respectively. The small RMSE values obtained indicates the successful performance of the designed pulse oximeter.

Inpatient comparison of wireless and wired pulse oximetry in neonates

To compare oxygen saturation (SpO2) and heart rate (HR) recorded by a reference wired pulse oximeter to a wireless pulse oximeter in inpatient neonates. Term infants born≥37 + 0 weeks and preterm infants born≤35 + 0 weeks gestation were enrolled and time-matched data pairs were obtained. The primary outcome was intraclass correlation coefficient and r-values between the two oximeters for heart rate and oxygen saturation. Thirty term and 20 preterm neonates were enrolled. There was a high degree of correlation between the two oximeters for HR (r = 0.926) among all 50 infants, and excellent interclass correlation (ICC = 0.961), but there were no bradycardia episodes in either term or preterm infants. There was a lesser degree of correlation for SpO2 values in the term and preterm groups (r = 0.242; 0.521, respectively) along with moderate interclass correlation (ICC = 0.719) but few episodes of hypoxemia≤90% occurred in enrolled subjects. There were no significant differences between the wireless and reference wired oximeters for assessing HR. There was less correlation between the two oximeters for monitoring SpO2 in both the term and preterm group. Wireless pulse oximetry may have practical advantages for use in inpatient neonates, but additional studies are needed that include bradycardia and desaturation events to delineate this question.

Multiple H-bonding chain extender-based polyurethane: Ultrastiffness, hot-melt adhesion, and 3D printing finger orthosis

Mallet finger is a common athletic injury, and the current treatment involves fixing the injured finger by a splint or orthosis. 3D printing technology offers an innovative way to customize patient-specific finger orthosis that fits the individual anthropometrics. However, the existing printed materials cannot combine the high stiffness and toughness to construct an ideal finger orthosis. Herein, we report a new chain extender carrying one amide and one urea group in the side chain, and utilize it to extend polyurethane prepolymer to fabricate a highly stiff and tough thermoplastic polyurethane (TPU). Strong and mobile H-bonds in the side chain promote the formation of multiphase-separated structure in the TPU network, thus endowing this TPU with high Young’s modulus (213.0 ± 3.7 MPa) and high toughness (47.8 ± 1.9 MJ m−3). Due to the dynamic H-bonds in the polymer network, this TPU exhibits an excellent 3D printing ability, and can be used to print finger orthosis by fused deposition modeling technology at an elevated temperature. The printed finger orthosis can be attached with a wireless pulse oximeter by virtue of TPU adhesiveness, thus monitoring vital physiological signals on the injured index finger that can be well fixed by the stiff orthosis.

Investigation of Wireless Pulse Oximeters for Smartphone-based Remote Monitoring of Lung Health

Coronavirus has the greatest effect on the human lungs. This is why lungs of patients with COVID- 19 require constant medical monitoring. One of the tools for the lungs condition monitoring is based on the wireless pulse oximeters connected to smartphones. There is an attempt to analyze the types of pulse oximeters, their technical characteristics, principles of operation and basic requirements for these measuring instruments in the article. According to this study, the most effective pulse oximeters for 24/7 monitoring of lung function were selected. Principles of pulse oximeter functioning and mathematical basis of its operation have been described. The criteria for pulse oximeter selection have been determined, and comparative analysis of pulse oximeters with wireless communication has been conducted.

Evaluation of the efficacy of wireless sterilizable pulse oximeter in assessment of bowel viability during surgery

Background Intestinal viability is crucial before commencement of any anastomoses or establishment of stomas after resection of the gut for any surgical reason, and depending on the clinical sense and subjective methods alone may result in disastrous results and complications affecting the outcomes of the surgical procedures. There are many techniques available nowadays for assessing bowel viability, but most of them are technically demanding and not usually available in the operating theater, besides the cost of many of them, which may represent another added burden. For all the aforementioned reasons, the wireless pulse oximeter (PO) has emerged as a possible new method which can aid in assessment of bowel viability during surgeries with the advantages of availability, low cost, and simple rapid way of gut viability assessment. Purpose The aim of this study was to evaluate the capability of the wireless PO in discrimination between viable and nonviable intestine intraoperatively before establishment of stomas or intestinal anastomoses. Study design This was a prospective study that included 40 patients who were evaluated intraoperatively by the wireless PO to assess the viability of the proximal and distal ends of the intestine. The intestinal viability in the first 10 patients was also evaluated by the fluorescein dye in addition to the PO. Here, fluorescein was used as a well-established method to validate the new technique of the PO. All the readings were recorded, and patients were followed up for 2 weeks postoperatively to detect any complications related to intestinal ischemia. Results Three cases were complicated: two cases of failed anastomosis with leakage and the third case was ischemic end colostomy stoma. The mean values of PO readings in the noncomplicated group (37 cases) were 95.65 and 96.32% in the proximal and distal segments, respectively, whereas in the complicated group (three cases), mean values were 89 and 87% in the proximal and distal segments, respectively. Conclusion The PO device is safe, portable, and nonsophisticated, which can be used easily by surgeons in assessment of bowel viability during surgery. It takes less time to assess the intestinal viability and is very cost-effective, as one device can be used in multiple patients.

Hypoxemia following hospital discharge after fast-track hip and knee arthroplasty - A prospective observational study subanalysis.

Post-operative hypoxemia is prevalent in hospitalized patients and may adversely affect recovery. However, little data exist on the post-discharge phase or details on duration, severity and potential risk factors. Thus, we investigated the incidence and risk factors for severe desaturation during the first post-operative week after THA/TKA by continuous nocturnal oxygen saturation monitoring. The study was a secondary analysis of a prospective cohort study of 112 patients undergoing fast-track THA/TKA. Patients with known sleep apnoea were excluded. Oxygen saturation and heart rate were recorded by a wireless wrist-worn pulse oximeter 2 nights before and 7 nights after surgery. Data on demographics, opioid consumption and cognitive function were collected from medical charts, patient diaries and clinical testing respectively. The primary outcome was occurrence of severe desaturation defined as periods with saturation <85% lasting ≥10minutes. Secondary outcomes included description of various saturation levels and relevant risk factors. Severe oxygen desaturation occurred in 35% of the patients during the first post-operative week. Duration and severity of hypoxemic episodes increased after the first post-operative day. Pre-operative episodes of hypoxemia significantly increased the risk of post-operative hypoxemic events (OR 2.4-4.4, CI 0.4-46), while pre- and post-operative opioid use, age, gender, ASA classification, type of surgery or anaesthesia were significantly related to the development of post-operative hypoxemia. One third of the patients suffered from increased and prolonged episodes of severe nocturnal hypoxemia during the first week after THA/TKA discharge. Increased risk for severe hypoxemic episodes was related to pre-operative hypoxemia.

The Mobile-Based 6-Minute Walk Test: Usability Study and Algorithm Development and Validation.

BackgroundThe 6-min walk test (6MWT) is a convenient method for assessing functional capacity in patients with cardiopulmonary conditions. It is usually performed in the context of a hospital clinic and thus requires the involvement of hospital staff and facilities, with their associated costs.ObjectiveThis study aimed to develop a mobile phone–based system that allows patients to perform the 6MWT in the community.MethodsWe developed 2 algorithms to compute the distance walked during a 6MWT using sensors embedded in a mobile phone. One algorithm makes use of the global positioning system to track the location of the phone when outdoors and hence computes the distance travelled. The other algorithm is meant to be used indoors and exploits the inertial sensors built into the phone to detect U-turns when patients walk back and forth along a corridor of fixed length. We included these algorithms in a mobile phone app, integrated with wireless pulse oximeters and a back-end server. We performed Bland-Altman analysis of the difference between the distances estimated by the phone and by a reference trundle wheel on 49 indoor tests and 30 outdoor tests, with 11 different mobile phones (both Apple iOS and Google Android operating systems). We also assessed usability aspects related to the app in a discussion group with patients and clinicians using a technology acceptance model to guide discussion.ResultsThe mean difference between the mobile phone-estimated distances and the reference values was −2.013 m (SD 7.84 m) for the indoor algorithm and −0.80 m (SD 18.56 m) for the outdoor algorithm. The absolute maximum difference was, in both cases, below the clinically significant threshold. A total of 2 pulmonary hypertension patients, 1 cardiologist, 2 physiologists, and 1 nurse took part in the discussion group, where issues arising from the use of the 6MWT in hospital were identified. The app was demonstrated to be usable, and the 2 patients were keen to use it in the long term.ConclusionsThe system described in this paper allows patients to perform the 6MWT at a place of their convenience. In addition, the use of pulse oximetry allows more information to be generated about the patient’s health status and, possibly, be more relevant to the real-life impact of their condition. Preliminary assessment has shown that the developed 6MWT app is highly accurate and well accepted by its users. Further tests are needed to assess its clinical value.

Technical note: Evaluation of a wireless pulse oximeter for measuring arterial oxygen saturation and pulse rate in newborn Holstein Friesian calves

Pulse oximetry is a well-established technique in human and veterinary medicine. In farm animals, it could also be a useful tool for the detection of critical conditions relating to oxygen supply and the cardiovascular system. Among other uses, an innovative application could be the monitoring of fetuses during birth. This could help in the early identification of critical situations and support farmers and veterinarians in their decision to start obstetric or life-support interventions. Until now, however, its use in ruminant medicine was still limited to experimental applications. The objective of this study was to evaluate the accuracy of the Radius-7 Wearable Pulse CO-Oximeter (Masimo Corporation, Irvine, CA) for monitoring vital parameters in newborn calves. All measurements were conducted on animals in the lying down position. The sensor of the pulse oximeter was placed in the interdigital space of the calves' front legs and fixed with a homemade latex hoof cover. The pulsoximetric measurements of arterial oxygen saturation (SpO2) in 40 newborn calves were compared with the corresponding results (SaO2) from a portable blood gas analyzer (VetScan iStat1, Abaxis Inc., Union City, CA), which served as the reference. For this, an arterial blood sample was taken from the medial intermediate branch of the caudal auricular artery. In addition, the pulse rate was measured in 10 calves aged between 0 and 7 d with the pulse oximeter and simultaneously with a heart rate belt (Polar Equine Belt, Polar Electro Oy, Kempele, Finland) to determine their level of agreement. Spearman correlation coefficient for oxygen saturation was 93.8% for the pulse oximeter and the blood gas analyzer, and 97.7% for the pulse rate measured with the pulse oximeter and the heart rate belt. Bland-Altman plots revealed an overestimation of SaO2 by 2.95 ± 6.39% and an underestimation of the pulse rate by -0.41 ± 3.18 beats per minute compared with the corresponding reference methods. In summary, the pulse oximeter is suitable for continuous monitoring of arterial oxygen saturation and pulse in newborn Holstein Friesian calves. For practical use, purpose-built technical equipment is required to attach the sensor to the calves' legs.

Factors which influence concordance among measurements obtained by different pulse oximeters currently used in some clinical situations.

To evaluate both concordance among those measurements obtained by three different pulse oximeters currently used by nursing professionals in hospital units and the factors which can influence this concordance. Many models of wireless pulse oximeters in the present market do not offer possibility of calibration and, therefore, they do not ensure patients' safety in daily clinical practice. This is a descriptive and cross-sectional study. The sample of patients (140) was selected from such hospital units, and all of them had to fulfil inclusion and exclusion criteria for participation. The instruments used to carry out this research were a monitor (calibrated), two models of portable wireless pulse oximeters (used for 3years by the nursing staff, without being calibrated), a tympanic thermometer and a weather meter. The concordance correlation coefficient (CCC) was used to establish the concordance, whereas the Landis-Koch criteria were used to interpret the results. The concordance among the three devices was considered as "good" (CCC: 0.925 and 0.974 (95%)). The CCC (0.925) for saturation measures was regarded as "very good"/"almost perfect," and the pulse measure was considered as "very good" CCC 0.974, providing in both cases a high level of concordance (CCC>0.91). The overall concordance as regards pulse and oxygen saturation among the three pulse oximeters analysed is considered as "very good" according to the Landis-Koch criteria. There exists a "very good" concordance among two wireless oximeters which have been used by the health staff for 3years and which did not offer any possibility of calibration and one monitor which belongs to the healthcare institution. This aspect is of crucial importance in daily clinical practice, and it is also relevant to ensure patient's safety.

A Comparison of Wireless Pulse Oximetry Technologies during SustainedShivering in Post-Operative Patients

Background: Pulse oximetry measures oxygen saturation in arterial blood non-invasively and is routinely practiced in many clinical settings. Technological advancements have expanded the performance capabilities of these devices to operate wirelessly, making pulse oximetry measures more convenient to obtain. Factors such as patient motion however can potentially complicate the ability to retrieve these measures. We examined the performance of two wireless pulse oximeters in patients who shiver postoperatively. Methods: Two additional pulse oximeter sensors (Masimo and Nonin) were added to 30 patients who shivered post-operatively and met eligibility criteria. Dropout rates were calculated by dividing the number of times that each instrument displayed no SpO2 or pulse rate value by the total time both sensors were in camera view for that subject. We used Wilcoxon matched pairs tests to compare the average time until the first reading displayed on the sensor for each device as well as dropout times. Dropout events were also compared using McNemar's test. Results: Drops in signal occurred in thirteen subjects. The Masimo sensor had more dropouts and a longer average drop duration, which was found to be statistically significant (p=0.02). Masimo's sensor required more s on average than Nonin's (8.86>8.78) to display the first reading, but this was not found to be statistically significant (p=0.90). Masimo also had a higher percentage of drops however this was not statistically significant (p=0.07). Conclusion: Overall incidence of shivering was low among patients in this setting (0.1%). More than 1/3 of subjects experienced drops during identical time intervals indicating that motion artifact may impact results regardless of technology. Additionally, Masimo's sensor is not meant for clinical use thereby raising questions regarding our statistically significant result in this particular setting. Combined with results from part I of this study, we cannot confidently detect a statistically significant difference between manufacturers.

Low Cost Real-Time Portable Pulse Oximeter with Wireless Network

To facilitate quicker detection of symptoms of cardiovascular and respiratory disorders, the use of smaller portable wireless sensors which consume less power is an essential requirement. Wireless pulse oximeter are convenient devices which aid to remotely monitor a patient’s heart rate and blood oxygen saturation (SpO\(_2\)), The result of this studyshows a developed portable, low cost device which can be used to measure the heart rate, and SpO\(_2\) of an individual. To this end, a small pulse oximeter was developed; which used an elastic transmissive mode finger probe to measure the heart rate and SpO\(_2\). The device could successfully measure these vital signs and display on a LCD screen. The readings taken from individual for a period of one minute shows average heart rate of 75.6 bpm at zero offset and the average SpO\(_2\) readings derived from the device was 98.7% at zero offset. The model designed is also rechargeable to make it more sustainable for use in rural areas where there is insufficient power supply. The prototype pulse oximeter designed is portable, consumes less power and capable of sending processed measured data to an online database via a WLAN network thereby satisfying the criteria for sustainable telemedicine.This device is therefore recommended for use in local hospitals and remote medical centre to aid easier detection and prevention of critical medical diseases.

Design of a finger base-type pulse oximeter.

A pulse oximeter is a common medical instrument used for noninvasively monitoring arterial oxygen saturation (SpO2). Currently, the fingertip-type pulse oximeter is the prevalent type of pulse oximeter used. However, it is inconvenient for long-term monitoring, such as that under motion. In this study, a wearable and wireless finger base-type pulse oximeter was designed and implemented using the tissue optical simulation technique and the Monte Carlo method. The results revealed that a design involving placing the light source at 135°-165° and placing the detector at 75°-90° or 90°-105° yields the optimal conditions for measuring SpO2. Finally, the wearable and wireless finger base-type pulse oximeter was implemented and compared with the commercial fingertip-type pulse oximeter. The experimental results showed that the proposed optimal finger base-type pulse oximeter design can facilitate precise SpO2 measurement.

Design of Wireless Intra-Operative Pulse Oximeter With Reticulated Pressure-Sensitive Head1

Design of Wireless Intra-Operative Pulse Oximeter With Reticulated Pressure-Sensitive Head1

Novel wearable and wireless ring-type pulse oximeter with multi-detectors.

The pulse oximeter is a popular instrument to monitor the arterial oxygen saturation (SPO2). Although a fingertip-type pulse oximeter is the mainstream one on the market at present, it is still inconvenient for long-term monitoring, in particular, with respect to motion. Therefore, the development of a wearable pulse oximeter, such as a finger base-type pulse oximeter, can effectively solve the above issue. However, the tissue structure of the finger base is complex, and there is lack of detailed information on the effect of the light source and detector placement on measuring SPO2. In this study, the practicability of a ring-type pulse oximeter with a multi-detector was investigated by optical human tissue simulation. The optimal design of a ring-type pulse oximeter that can provide the best efficiency of measuring SPO2 was discussed. The efficiency of ring-type pulse oximeters with a single detector and a multi-detector was also discussed. Finally, a wearable and wireless ring-type pulse oximeter was also implemented to validate the simulation results and was compared with the commercial fingertip-type pulse oximeter.

Concordance among Measurements Obtained by Three Pulse Oximeters Currently Used by Health Professionals.

Oxygen saturation is considered as the 5(th) vital sign. Presently, there exist fixed and wireless pulse oximeters, being the latter most widely used in the last years. Some of them have no possibility of calibration. This situation leads the health staff to adopt therapeutic attitudes which can be wrong. Therefore, it is extremely important to know if these wireless oximeters show a right concordance as regards measurements, since it is of great interest in daily clinical practice. To evaluate concordance among measurements obtained by three different pulse oximeters currently used by health professionals. This is an observational, descriptive and cross-sectional study related to the concordance of the results obtained in measurements collected by three different pulse oximeters (one monitor and two wireless oximeters) which are available and in use in this hospital unit. The sample size calculation was performed for a concordance above 0.81 and an estimation error which did not exceed 0.20. The intraclass correlation index (ICI) was used to establish the concordance whereas the Landis-Koch criteria were used to interpret the results. Systematic errors were analyzed using the Bland-Altman plot. The overall concordance among the three pulse oximeters analyzed resulted in 0.88, a value considered as "good" according to the Landis-Koch criteria. The results obtained show that in daily clinical practice both wireless pulse oximeters analyzed can be used with a certain reliability, taking into account the limitations of this research.

Onboard Tagging for Real-Time Quality Assessment of Photoplethysmograms Acquired by a Wireless Reflectance Pulse Oximeter

Onboard assessment of photoplethysmogram (PPG) quality could reduce unnecessary data transmission on battery-powered wireless pulse oximeters and improve the viability of the electronic patient records to which these data are stored. These algorithms show promise to increase the intelligence level of former "dumb" medical devices: devices that acquire and forward data but leave data interpretation to the clinician or host system. To this end, the authors have developed a unique onboard feature detection algorithm to assess the quality of PPGs acquired with a custom reflectance mode, wireless pulse oximeter. The algorithm uses a Bayesian hypothesis testing method to analyze four features extracted from raw and decimated PPG data in order to determine whether the original data comprise valid PPG waveforms or whether they are corrupted by motion or other environmental influences. Based on these results, the algorithm further calculates heart rate and blood oxygen saturation from a "compact representation" structure. PPG data were collected from 47 subjects to train the feature detection algorithm and to gauge their performance. A MATLAB interface was also developed to visualize the features extracted, the algorithm flow, and the decision results, where all algorithm-related parameters and decisions were ascertained on the wireless unit prior to transmission. For the data sets acquired here, the algorithm was 99% effective in identifying clean, usable PPGs versus nonsaturated data that did not demonstrate meaningful pulsatile waveshapes, PPGs corrupted by motion artifact, and data affected by signal saturation.

Design and evaluation of a wireless electronic health records system for field care in mass casualty settings

There is growing interest in the use of technology to enhance the tracking and quality of clinical information available for patients in disaster settings. This paper describes the design and evaluation of the Wireless Internet Information System for Medical Response in Disasters (WIISARD). WIISARD combined advanced networking technology with electronic triage tags that reported victims' position and recorded medical information, with wireless pulse-oximeters that monitored patient vital signs, and a wireless electronic medical record (EMR) for disaster care. The EMR system included WiFi handheld devices with barcode scanners (used by front-line responders) and computer tablets with role-tailored software (used by managers of the triage, treatment, transport and medical communications teams). An additional software system provided situational awareness for the incident commander. The WIISARD system was evaluated in a large-scale simulation exercise designed for training first responders. A randomized trial was overlaid on this exercise with 100 simulated victims, 50 in a control pathway (paper-based), and 50 in completely electronic WIISARD pathway. All patients in the electronic pathway were cared for within the WIISARD system without paper-based workarounds. WIISARD reduced the rate of the missing and/or duplicated patient identifiers (0% vs 47%, p<0.001). The total time of the field was nearly identical (38:20 vs 38:23, IQR 26:53-1:05:32 vs 18:55-57:22). Overall, the results of WIISARD show that wireless EMR systems for care of the victims of disasters would be complex to develop but potentially feasible to build and deploy, and likely to improve the quality of information available for the delivery of care during disasters.