An innovative method to prevent infection when measuring the arterial blood gas SpO2 saturation

Background

Patients are hospitalized for extended periods, particularly in intensive care units (ICUs). As a result, the saturation probe (pulse oximeter) remains attached for an extended period and microorganisms can grow in the wet environment. If the pulse oximeters are not reprocessed, cross-infection may occur. The literature contains several studies in which gloves were used for the measurement while various SpO2 (peripheral arterial oxygen saturation) measurements were compared with each other. However, such comparisons have yet to be made with the results of arterial blood gas SpO2 measurements by pulse oximeter, considered as the gold standard. The present study aimed to compare arterial blood gas values with the fingertip saturation measurement performed by having adult patients wear gloves of different colors, one after the other, on their fingers and determining the effect of the differently colored gloves (transparent, white, black, light blue) on saturation values.

Methods

The study was conducted on 54 patients in an ICU. Intra-arterial blood gas SpO2 results were measured. Oxygen saturation was measured while the patient 1. did not wear gloves and 2. sequentially wore a series of gloves of different colors. Paired t-test, correlation analysis, and Bland Altman charts were used to evaluate the results.

Results

The mean SpO2% value of the participants' intra-arterial blood gas measurements was 97.76±2.04. The mean SpO2% value obtained from the measurements of the fingers with a transparent glove was 0.43 points lower than the mean SpO2% value of the intra-arterial blood gas measurements (t=0.986, p=0.61). The mean SpO2% value obtained from the measurements of the fingers with a white glove was 0.93 points lower than the mean SpO2% value of the intra-arterial blood gas measurements (t=1.157, p=0.093).

Conclusion

Of the measurements performed with a glove, the mean SpO2% value obtained from the measurements of the fingers with a transparent glove was more consistent with the mean SpO2% value of the intra-arterial blood gas measurements than measurement of the fingers without a glove.

Application of Oxygen Saturation Test after Replantation of Avulsed Immature Permanent Teeth: A Prospective Observational Study

INTRODUCTION

The evaluation of pulp status is crucial for avulsed immature permanent teeth after replantation. In addition to commonly used clinical and radiographic examinations providing clinical evidence, the oxygen saturation test may offer valuable assistance. The aim of this study was to analyze the efficacy of a pulse oximeter in evaluating pulp status in avulsed and replanted immature permanent teeth.

METHODS

A prospective observational study was performed including 51 avulsed and replanted immature permanent teeth. Routine clinical and radiographic examinations were performed and used as the basis for the diagnosis of pulp status during the 1-year follow-up period. Meanwhile, the oxygen saturation values of these teeth were recorded using a modified pulse oximeter at each visit.

RESULTS

Seven teeth completed pulp revascularization (success group), whereas 44 teeth failed to revascularize (failure group). Abnormal clinical and/or radiographic manifestations in the failure group were observed at an average period of 42.7 days, which was too late because a high incidence of inflammatory root resorption (43.18%) had occurred. For oxygen saturation tests, teeth in the success group showed an immediate postreplantation oxygen value of 70.71 ± 3.35, then an upward trend starting from the 2-week postreplantation visit, and a significantly increased final value of 81.86 ± 2.34 at the 1-year visit. In contrast, no increase trend was found for teeth in the failure group because abnormal clinical and/or radiographic manifestations emerged.

CONCLUSIONS

The oxygen saturation test is a reliable diagnostic method to evaluate pulp status of avulsed teeth as early as 2 weeks after replantation.

Wireless Patient Monitoring System Based on Smart Wristbands and Central user Interface Software

In this article, a patient monitoring system is proposed that is able to obtain heart rate and oxygen saturation (SpO2) levels of patients, identify abnormal conditions, and inform emergency status to the nurses. The proposed monitoring system consists of smart patient wristbands, smart nurse wristbands, central monitoring user interface (UI) software, and a wireless communication network. In the proposed monitoring system, a unique smart wristband is dedicated to each of the patients and nurses. To measure heart rate and SpO2 level, a pulse oximeter sensor is used in the patient wristbands. The output of this sensor is transferred to the wristband's microcontroller where heart rate and SpO2 are calculated through advanced signal processing algorithms. Then, the calculated values are transmitted to central UI software through a wireless network. In the UI software, received values are compared with their normal values and a predefined message is sent to the nurses' wristband if an abnormal condition is identified. Whenever this message is received by a nurse's wristband, an acoustic alarm with vibration is generated to inform an emergency status to the nurse. By doing so, health services are delivered to the patients more quickly and as a result, the probability of the patient recovery is increased effectively.

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.

Resource Use and Clinical Outcomes in Infants with Supraventricular Tachycardia Monitored with the Owlet Smart Sock

OBJECTIVES

To describe the prevalence of Owlet Smart Sock (OSS) use in infants with supraventricular tachycardia (SVT) and associated demographic and clinical characteristics of users and to analyze the association of OSS use on medical resource use and clinical outcomes from emergency department (ED) encounters for SVT.

STUDY DESIGN

This was a single-center, retrospective cohort study of infants with confirmed SVT from 2015 to 2022. OSS users and nonusers were compared across clinical and demographic parameters. Medical resource use (phone calls, office visits, ED visits) and outcomes (need for intensive care, length of stay, echocardiographic function, clinical appearance) were compared between OSS users and nonusers.

RESULTS

Of 133 infants with SVT, OSS was used by 31 of 133 (23%), purchased before SVT diagnosis in 5 in 31 (16%) of users. No demographic difference was found between OSS users and nonusers. OSS users had more phone notes than nonusers, (P = .002) and more ED visits (P = .03), but the number of office visits and medication adjustments did not differ. During ED presentation, OSS users had better preserved left ventricular ejection fraction on echocardiogram (P = .04) and lower length of hospital stay by a mean 1.7 days (P = .02).

CONCLUSIONS

OSS is used by a portion of infants with SVT. It is associated with more frequent phone calls and ED visits but lower length of stay and better-preserved cardiac function upon presentation.

Exploring the Hidden Complexity: Entropy Analysis in Pulse Oximetry of Female Athletes

This study examines the relationship between physiological complexity, as measured by Approximate Entropy (ApEn) and Sample Entropy (SampEn), and fitness levels in female athletes. Our focus is on their association with maximal oxygen consumption (VO2,max). Our findings reveal a complex relationship between entropy metrics and fitness levels, indicating that higher fitness typically, though not invariably, correlates with greater entropy in physiological time series data; however, this is not consistent for all individuals. For Heart Rate (HR), entropy measures suggest stable patterns across fitness categories, while pulse oximetry (SpO2) data shows greater variability. For instance, the medium fitness group displayed an ApEn(HR) = 0.57±0.13 with a coefficient of variation (CV) of 22.17 and ApEn(SpO2) = 0.96±0.49 with a CV of 46.08%, compared to the excellent fitness group with ApEn(HR) = 0.60±0.09 with a CV of 15.19% and ApEn(SpO2) =0.85±0.42 with a CV of 49.46%, suggesting broader physiological responses among more fit individuals. The larger standard deviations and CVs for SpO2 entropy may indicate the body's proficient oxygen utilization at higher levels of physical demand. Our findings advocate for combining entropy metrics with wearable sensor technology for improved biomedical analysis and personalized healthcare.

Implementation of a Triage Protocol Outside the Hospital Setting for Timely Referral During the COVID-19 Second Wave in Chennai, India

India experienced a surge in COVID-19 cases during the second wave in the period of April-June 2021. A rapid rise in cases posed challenges to triaging patients in hospital settings. Chennai, the fourth largest metropolitan city in India with an 8 million population, reported 7564 COVID-19 cases on May 12, 2021, nearly 3 times higher than the number of cases in the peak of COVID-19 in 2020. A sudden surge of cases overwhelmed the health system. We had established standalone triage centers outside the hospitals in the first wave, which catered to up to 2500 patients per day. In addition, we implemented a home-based triage protocol from May 26, 2021, to evaluate patients with COVID-19 who were aged ≤45 years without comorbidities. Among the 27,816 reported cases between May 26 and June 24, 2021, a total of 16,022 (57.6%) were aged ≤45 years without comorbidities. The field teams triaged 15,334 (55.1%), and 10,917 (39.2%) patients were evaluated at triage centers. Among 27,816 cases, 19,219 (69.1%) were advised to self-isolate at home, 3290 (11.8%) were admitted to COVID-19 care centers, and 1714 (6.2%) were admitted to hospitals. Only 3513 (12.7%) patients opted for the facility of their choice. We implemented a scalable triage strategy covering nearly 90% of the patients in a large metropolitan city during the COVID-19 surge. The process enabled early referral of high-risk patients and ensured evidence-informed treatment. We believe that the out-of-hospital triage strategy can be rapidly implemented in low-resource settings.

Experiences of Patients With Chronic Obstructive Pulmonary Disease Using the Apple Watch Series 6 Versus the Traditional Finger Pulse Oximeter for Home SpO2 Self-Monitoring: Qualitative Study Part 2

BACKGROUND

Amid the rise in mobile health, the Apple Watch now has the capability to measure peripheral blood oxygen saturation (SpO2). Although the company indicated that the Watch is not a medical device, evidence suggests that SpO2 measurements among patients with chronic obstructive pulmonary disease (COPD) are accurate in controlled settings. Yet, to our knowledge, the SpO2 function has not been validated for patients with COPD in naturalistic settings.

OBJECTIVE

This qualitative study explored the experiences of patients with COPD using the Apple Watch Series 6 versus a traditional finger pulse oximeter for home SpO2 self-monitoring.

METHODS

We conducted individual semistructured interviews with 8 female and 2 male participants with moderate to severe COPD, and transcripts were qualitatively analyzed. All received a watch to monitor their SpO2 for 5 months.

RESULTS

Due to respiratory distress, the watch was unable to collect reliable SpO2 measurements, as it requires the patient to remain in a stable position. However, despite the physical limitations and lack of reliable SpO2 values, participants expressed a preference toward the watch. Moreover, participants' health needs and their unique accessibility experiences influenced which device was more appropriate for self-monitoring purposes. Overall, all shared the perceived importance of prioritizing their physical COPD symptoms over device selection to manage their disease.

CONCLUSIONS

Differing results between participant preferences and smartwatch limitations warrant further investigation into the reliability and accuracy of the SpO2 function of the watch and the balance among self-management, medical judgment, and dependence on self-monitoring technology.

Recent Progress in Flexible and Wearable All Organic Photoplethysmography Sensors for SpO2 Monitoring

Flexible and wearable biosensors are the next-generation healthcare devices that can efficiently monitor human health conditions in day-to-day life. Moreover, the rapid growth and technological advancements in wearable optoelectronics have promoted the development of flexible organic photoplethysmography (PPG) biosensor systems that can be implanted directly onto the human body without any additional interface for efficient bio-signal monitoring. As an example, the pulse oximeter utilizes PPG signals to monitor the oxygen saturation (SpO2 ) in the blood volume using two distinct wavelengths with organic light emitting diode (OLED) as light source and an organic photodiode (OPD) as light sensor. Utilizing the flexible and soft properties of organic semiconductors, pulse oximeter can be both flexible and conformal when fabricated on thin polymeric substrates. It can also provide highly efficient human-machine interface systems that can allow for long-time biological integration and flawless measurement of signal data. In this work, a clear and systematic overview of the latest progress and updates in flexible and wearable all-organic pulse oximetry sensors for SpO2 monitoring, including design and geometry, processing techniques and materials, encapsulation and various factors affecting the device performance, and limitations are provided. Finally, some of the research challenges and future opportunities in the field are mentioned.

Preterm Infants off Positive Pressure Respiratory Support Have a Higher Incidence of Occult Cerebral Hypoxia

OBJECTIVE

To use cerebral near-infrared spectroscopy (NIRS) to quantify occult cerebral hypoxia across respiratory support modes in preterm infants.

STUDY DESIGN

In this prospective, longitudinal, observational study, infants ≤32 weeks gestation underwent serial pulse oximetry (oxygen saturation [SpO2]) and cerebral NIRS monitoring (4-6 hours per session) following a standardized recording schedule (daily for 2 weeks, every other day for 2 weeks, then weekly until 35 weeks corrected gestational age). Four calculations were made: median cerebral saturation, median cerebral hypoxia burden (proportion of NIRS samples below the hypoxia threshold [<67%]), median systemic saturation, and median systemic hypoxia burden (proportion of SpO2 samples below the desaturation threshold [<85%]). During each recording session, respiratory support mode was noted (room air, low-flow nasal cannula, high-flow nasal cannula, noninvasive positive pressure ventilation, continuous positive airway pressure, and invasive ventilation).

RESULTS

There were 1013 recording sessions made from 174 infants with a median length of 6.9 hours. Although the systemic (SpO2) hypoxia burden was significantly greater for infants on the highest respiratory support (invasive and noninvasive positive pressure ventilation), the cerebral hypoxia burden was significantly greater during recording sessions made on the lowest respiratory support (8% for room air; 29% for low-flow nasal cannula).

CONCLUSIONS

Premature infants on the highest levels of respiratory support have less cerebral hypoxia than those on lower respiratory support. These results raise concern about unrecognized cerebral hypoxia during lower acuity periods of neonatal intensive care unit hospitalization and adverse outcomes.

Evaluation of a Portable Blood Gas Analyzer for Prehospital Triage in Carbon Monoxide Poisoning: Instrument Validation Study

BACKGROUND

Carbon monoxide (CO) poisoning is an important cause of morbidity and mortality worldwide. Symptoms are mostly aspecific, making it hard to identify, and its diagnosis is usually made through blood gas analysis. However, the bulkiness of gas analyzers prevents them from being used at the scene of the incident, thereby leading to the unnecessary transport and admission of many patients. While multiple-wavelength pulse oximeters have been developed to discriminate carboxyhemoglobin (COHb) from oxyhemoglobin, their reliability is debatable, particularly in the hostile prehospital environment.

OBJECTIVE

The main objective of this pilot study was to assess whether the Avoximeter 4000, a transportable blood gas analyzer, could be considered for prehospital triage.

METHODS

This was a monocentric, prospective, pilot evaluation study. Blood samples were analyzed sequentially with 2 devices: the Avoximeter 4000 (experimental), which performs direct measurements on blood samples of about 50 µL by analyzing light absorption at 5 different wavelengths; and the ABL827 FLEX (control), which measures COHb levels through an optical system composed of a 128-wavelength spectrophotometer. The blood samples belonged to 2 different cohorts: the first (clinical cohort) was obtained in an emergency department and consisted of 68 samples drawn from patients admitted for reasons other than CO poisoning. These samples were used to determine whether the Avoximeter 4000 could properly exclude the diagnosis. The second (forensic) cohort was derived from the regional forensic center, which provided 12 samples from documented CO poisoning.

RESULTS

The mean COHb level in the clinical cohort was 1.7% (SD 1.8%; median 1.2%, IQR 0.7%-1.9%) with the ABL827 FLEX versus 3.5% (SD 2.3%; median 3.1%, IQR 2.2%-4.1%) with the Avoximeter 4000. Therefore, the Avoximeter 4000 overestimated COHb levels by a mean difference of 1.8% (95% CI 1.5%-2.1%). The consistency of COHb readings by the Avoximeter 4000 was excellent, with an intraclass correlation coefficient of 0.97 (95% CI 0.93-0.99) when the same blood sample was analyzed repeatedly. Using prespecified cutoffs (5% in nonsmokers and 10% in smokers), 3 patients (4%) had high COHb levels according to the Avoximeter 4000, while their values were within the normal range according to the ABL827 FLEX. Therefore, the specificity of the Avoximeter 4000 in this cohort was 95.6% (95% CI 87%-98.6%), and the overtriage rate would have been 4.4% (95% CI 1.4%-13%). Regarding the forensic samples, 10 of 12 (83%) samples were positive with both devices, while the 2 remaining samples were negative with both devices.

CONCLUSIONS

The limited difference in COHb level measurements between the Avoximeter 4000 and the control device, which erred on the side of safety, and the relatively low overtriage rate warrant further exploration of this device as a prehospital triage tool.

Does irradiation of the tooth structure interfere with oxygen saturation measured by pulse oximetry?-An ex vivo laboratorial study

The effect of tooth structure subjected to ionising radiation on oxygen saturation levels (SpO2 ) measured by pulse oximetry was investigated. Fifty-four extracted human third molars were sectioned mesiodistally. Pulse oximeter diodes were placed in prefabricated silicone moulds, secured on a vise with tooth surfaces placed between the diodes and the participant's finger, and SpO2 levels were measured. After that, the tooth surfaces were subjected to ionising radiation in fractionated doses of up to 70 Gy, and SpO2 was measured according to the protocol described. The Kolmogorov-Smirnov test was used for the analysis of normality of the quantitative variables, and Student's t-test compared mean SpO2 levels before and after irradiation. Mean SpO2 after irradiation was 94.6 ± 0.9%, without a statistically significant difference from SpO2 before irradiation, which was 94.7 ± 0.6%. Irradiation of the tooth structure did not interfere with SpO2 levels measured by pulse oximetry.

Knowledge of pulse oximetry among emergency and critical care nurses

BACKGROUND

The pulse oximeter is a simple, cost-effective and reliable device for estimating arterial blood oxygen saturation. Nurses are required to be knowledgeable in pulse oximeter use. Little is known about nurses' knowledge of pulse oximetry in the Middle East region.

AIM

To assess nurses' knowledge of pulse oximetry among emergency and critical care nurses and to explore predictors of nurses' knowledge of pulse oximetry.

METHODS

This is the second part of data analysis that was first presented in the 'proficiency in ECG' study conducted in Jordan. The original data used for both parts of analysis included a questionnaire with two tests; a knowledge of pulse oximeter test and an ECG proficiency test. Participants were asked to take, alone without receiving assistance, both tests. In this study, the second part of analysis, the focus is on the pulse oximeter test. The test consisted of 21 items that emphasize knowledge of basic physiological principles as well as device limitations; whether technical or interpretation. The test administration procedure also included asking participants to provide socio-demographic variables. In the original data collected in both parts of analysis, nurses working in the emergency department, cardiac care units or intensive care units from nine different hospitals (1 governmental, 6 private and 2 educational) and holding a bachelor degree or higher were asked to participate.

RESULTS

The total number of participating nurses was 210; out of 247 approached (response rate, 85%). The mean score in the nurses' knowledge of pulse oximetry test was 12.33 out of 21, corresponding to 58.7%. The clinical area currently working in predicted the knowledge of pulse oximetry test score after controlling for all other variables. Emergency department and intensive care unit nurses scored higher than cardiac care unit nurses by 1.86 and 1.63 points respectively (58.2% and 60% respectively).

CONCLUSION

Nurses consistently report inadequate education and training concerning pulse oximeter use and interpretation. A revision to hospital in-service education seminars and undergraduate nurses' curriculum to assure adequate preparation is needed.

RELEVANCE TO CLINICAL PRACTICE

Knowledge of pulse oximetry among emergency and critical care nurses is modest. This is a challenge worldwide. Predictors of nurses' knowledge of pulse oximetery are the clinical area currently working in (ICU and ED nurses are more knowledgeable than CCU nurses), proficiency in electrocardiography and taking an advanced cardiac life support course.

COVID-19 Proactive Disease Management Using COVID Virtual Hospital in a Rural Community

Purpose

A community teaching hospital serving a rural population established an intensive "hospital at home" program for patients with COVID-19 utilizing disease risk stratification and pulse oximeter readings to dictate nurse and clinician contact. Herein, we report patient outcomes and provider experiences resulting from this "virtual" approach to triaging pandemic care.

Methods

COVID-19-positive patients appropriate for outpatient management were enrolled in our COVID Virtual Hospital (CVH). Patients received pulse oximeters and instructions for home monitoring of vital signs. CVH nurses contacted the patient within 12-48 hours. The primary care provider was alerted of the patient's diagnosis and held a virtual visit with patient within 2-3 days. Nurses completed a triage form during each patient call; the resulting risk score determined timing of subsequent calls. CVH-relevant patient outcomes included emergency department (ED) visits, mortality, and disease-related hospitalization. Additionally, a survey of providers was conducted to assess CVH experience.

Results

From April 22, 2020, to December 21, 2020, 1916 patients were enrolled in the CVH, of which 195 (10.2%) had subsequent visits to the ED. Among those 195 ED visits, 102 (52.3%) were nurse-directed while 93 (47.7%) were patient self-directed; 88 (86.3%) nurse-directed ED visits were subsequently admitted to inpatient care and 14 were discharged home. Of the 93 self-directed ED visits, 3 (3.2%) were admitted. A total of 91 CVH patients (4.7%) were ultimately admitted to inpatient care. Seven deaths occurred among CVH patients, 5 of whom had been admitted for inpatient care. Among 71 providers (23%) who responded to the survey, 94% and 93% agreed that the CVH was beneficial to providers and patients, respectively.

Conclusions

Proactive in-home triage of patients with COVID-19 utilizing a virtual hospital model minimized unnecessary presentations to ED and likely prevented our rural hospital from becoming overwhelmed during year one of the pandemic.

Pulse Wave Amplitude Drops Index: A Biomarker of Cardiovascular Risk in Obstructive Sleep Apnea

Rationale: It is currently unclear which patients with obstructive sleep apnea (OSA) are at increased cardiovascular risk. Objective: To investigate the value of pulse wave amplitude drops (PWADs), reflecting sympathetic activations and vasoreactivity, as a biomarker of cardiovascular risk in OSA. Methods: PWADs were derived from pulse oximetry-based photoplethysmography signals in three prospective cohorts: HypnoLaus (N = 1,941), the Pays-de-la-Loire Sleep Cohort (PLSC; N = 6,367), and "Impact of Sleep Apnea syndrome in the evolution of Acute Coronary syndrome. Effect of intervention with CPAP" (ISAACC) (N = 692). The PWAD index was the number of PWADs (>30%) per hour during sleep. All participants were divided into subgroups according to the presence or absence of OSA (defined as ⩾15 or more events per hour or <15/h, respectively, on the apnea-hypopnea index) and the median PWAD index. Primary outcome was the incidence of composite cardiovascular events. Measurements and Main Results: Using Cox models adjusted for cardiovascular risk factors (hazard ratio; HR [95% confidence interval]), patients with a low PWAD index and OSA had a higher incidence of cardiovascular events compared with the high-PWAD and OSA group and those without OSA in the HypnoLaus cohort (HR, 2.16 [1.07-4.34], P = 0.031; and 2.35 [1.12-4.93], P = 0.024) and in the PLSC (1.36 [1.13-1.63], P = 0.001; and 1.44 [1.06-1.94], P = 0.019), respectively. In the ISAACC cohort, the low-PWAD and OSA untreated group had a higher cardiovascular event recurrence rate than that of the no-OSA group (2.03 [1.08-3.81], P = 0.028). In the PLSC and HypnoLaus cohorts, every increase of 10 events per hour in the continuous PWAD index was negatively associated with incident cardiovascular events exclusively in patients with OSA (HR, 0.85 [0.73-0.99], P = 0.031; and HR, 0.91 [0.86-0.96], P < 0.001, respectively). This association was not significant in the no-OSA group and the ISAACC cohort. Conclusions: In patients with OSA, a low PWAD index reflecting poor autonomic and vascular reactivity was independently associated with a higher cardiovascular risk.

Monitoring Perfusion Index in Patients Presenting to the Emergency Department Due to Drug Use

(1) Background: The perfusion index (PI) represents the ratio between pulsatile blood flow and non-pulsatile blood flow in the peripheral tissue. (2) We aimed to investigate the blood pressure perfusion of tissues and organs in ethnobotanical, synthetic cannabinoid and cannabis derivative consumers through the value of perfusion index. (3) Results: The patients enrolled were divided into two groups: group A, which included all patients who presented in the ED within the first three hours after consumption, and group B, which included those patients who presented more than three hours and up to 12 h after drug consumption. The average values of the PI in the case of group A/group B were 1.51 ± 1.07/4.55 ± 3.66. Statistically significant correlations in both groups were recorded between the drug intake ED admission, respiratory rate, peripheral blood oxygen saturation and tissue perfusion index (p < 0.001). The average value of the PI measured in group A was significantly lower compared to that measured in patients in group B. Therefore, we concluded that the perfusion of peripheral organs and tissues was lower in the first 3 h after drug administration. (4) Conclusions: PI plays an important role in the early detection of impaired organ perfusion and in monitoring tissue hypoxia. A decreased PI value may be an early indication of decreased perfusion organ damage.

Evaluation of the Effect of Antihypertensive Drugs on the Values of Dental Pulp Oxygen Saturation in Hypertension Patients: A Case-Control Study

Purpose This study aimed to know about the positive or negative effect of antihypertensive drugs of different groups on the values of dental pulp oxygen saturation in hypertension patients. Materials and Methods A case-control study to evaluate the impact of the antihypertensive drugs on the values of dental pulp oxygen saturation in hypertension patients. The studied sample consisted of 40 participants, and they were distributed into two groups: Group I (n=20): Hypertension patients treated with antihypertensive drugs, and Group II (n=20): Healthy participants. A finger pulse oximeter was recorded after a rest period of 15 minutes by BCI® Advisor® vital signs monitor. The patient was then asked to use a chlorhexidine digluconate mouth rinse for five minutes, and the two dental pulp pulse oximeters for the central upper incisors were also recorded for all participants. Data were analyzed using the Mann-Whitney U test. Results ​​​​​​The results showed that there was no significant difference between the finger pulse oximeters of the two studied groups (P-value = 0.421). The two dental pulp oxygen saturation was higher than the control group with statistically significant (P-value = 0.043, P-value = 0.002). Conclusions Within the limitation of this study, it can be concluded that antihypertensive drugs increase the dental pulp oxygen saturation in patients with hypertension who are treated with antihypertensive drugs, and thus there is a positive effect of these drugs in stimulating the dental pulp.

Parental Ability to Assess Pediatric Vital Signs

OBJECTIVE

To evaluate parents' ability to accurately assess their child's heart and respiratory rates (RRs) in the context of potential utility for telehealth visits.

STUDY DESIGN

In this controlled study of 203 child-parent pairs, parents measured their child's heart rate (HR) using 4 methods: palpation, auscultation, and 2 photoplethysmographic smartphone applications. Parents measured RR by inspecting the child and tapping the smartphone application. The gold standards were electrocardiogram for the HR and the child's breaths measured by a health care professional for 60 seconds for the RR. We plotted the measurements using a Bland-Altman plot with 95% limits of agreement.

RESULTS

Parents underestimated HR by palpation with a calculated bias of -18 beats per minute (bpm) (SD, 19), with limits of agreement ranging from -56 to 19 bpm. Parents overestimated and underestimated HR by auscultation with limits of agreement ranging from -53 to 46 bpm. Smartphone applications did not improve the accuracy of measurements. The accuracy of parental RR measurements was low. For young children, bias was -0.8 breaths per minute (brpm) (SD, 9.8) with limits of agreement from -20 to 19 brpm, and for older children, bias was 0.9 brpm (SD 7.4) with limits of agreement from 6 to 15 brpm. The sensitivity of parental subjective opinion to recognize accelerated RR was 37% (95% CI, 25%-51%).

CONCLUSION

Parents were not able to assess their child's RR or HR accurately. Digital remote assessment of children should not rely on parental measurements of vital signs.

Raynaud's Phenomenon During Non-operating Room Anesthesia: A Case Report

Non-operating room anesthesia challenges the anesthesiologist to deliver the same high-quality care as in the operating room. Amid the perplexity of the unfamiliar environment, scarcity of ancillary staff, and physical limitations, a distressing signal from pulse oximetry can cause a scare. We present a case of Raynaud's phenomenon in a patient posted for cystogastrostomy in the endoscopic retrograde cholangiopancreatography suite. The patient had pulmonary complications, a left-sided pleural effusion with underlying lung collapse related to pancreatitis; thus, a non-reassuring reading from pulse oximetry caused alarm. The patient had sinus tachycardia, with a heart rate of 104 beats per minute, and a blood pressure of 100/60 mmHg. We provided supplemental oxygen to the patient while planning for emergency tracheal intubation because of a low peripheral oxygen saturation of 87%. The patient was conscious during this time, prompting us to check the pulse oximeter probe. We then noticed that patient's digits had turned blue/pale. A sudden attack of Raynaud's in the perioperative period can mislead the caregivers, and an unwarranted state of panic can ensue.

Noninvasive Non-Contact SpO2 Monitoring Using an Integrated Polarization-Sensing CMOS Imaging Sensor

BACKGROUND

In the diagnosis and primary health care of an individual, estimation of the pulse rate and blood oxygen saturation (SpO2) is critical. The pulse rate and SpO2 are determined by methods including photoplethysmography (iPPG), light spectroscopy, and pulse oximetry. These devices need to be compact, non-contact, and noninvasive for real-time health monitoring. Reflection-based iPPG is becoming popular as it allows non-contact estimation of the heart rate and SpO2. Most iPPG methods capture temporal data and form complex computations, and thus real-time measurements and spatial visualization are difficult.

METHOD

In this research work, reflective mode polarized imaging-based iPPG is proposed. For polarization imaging, a custom image sensor with wire grid polarizers on each pixel is designed. Each pixel has a wire grid of varying transmission axes, allowing phase detection of the incoming light. The phase information of the backscattered light from the fingertips of 12 healthy volunteers was recorded in both the resting as well as the excited states. These data were then processed using MATLAB 2021b software.

RESULTS

The phase information provides quantitative information on the reflection from the superficial and deep layers of skin. The ratio of deep to superficial layer backscattered phase information is shown to be directly correlated and linearly increasing with an increase in the SpO2 and heart rate.

CONCLUSIONS

The phase-based measurements help to monitor the changes in the resting and excited state heart rate and SpO2 in real time. Furthermore, the use of the ratio of phase information helps to make the measurements independent of the individual skin traits and thus increases the accuracy of the measurements. The proposed iPPG works in ambient light, relaxing the instrumentation requirement and helping the system to be compact and portable.

Usefulness of a Pulse Oximeter and Multimodality Imaging for Diagnosing Platypnea-orthodeoxia Syndrome

Platypnea-orthodeoxia syndrome (POS) is a rare disease characterized by dyspnea and hypoxemia in orthostatism that improves in the recumbent position. We herein report an 81-year-old woman with dyspnea in the upright position following thoracic vertebral compression fractures. After the patient's daughter brought a recording showing decreasing SpO₂ (peripheral capillary oxygen saturation) in the upright position as measured by a portable pulse oximeter outside the hospital, a small atrial septal defect (ASD) was detected. A contrast echocardiogram and four-dimensional flow magnetic resonance imaging demonstrated a right-to-left shunt. The patient's symptoms dramatically improved after percutaneous ASD closure. In conclusion, such new technologies are useful for diagnosing POS.

Diagnostic Accuracy of Pulp Vitality Tests and Pulp Sensibility Tests for Assessing Pulpal Health in Permanent Teeth: A Systematic Review and Meta-Analysis

The current systematic review and meta-analysis was carried out to compare the diagnostic accuracy of pulp vitality and pulp sensibility tests in assessing pulpal health. PubMed/MEDLINE, Cochrane Central Register of Controlled Trials, Web of Science, Google Scholar and Open Grey databases were searched and after assessing eligibility criteria the data were extracted. True-positive, false-positive, true-negative, false-negative, sensitivity and specificity values were extracted or calculated if not presented. Quality of studies was evaluated based on the QUADAS 2 tool. Meta-analysis was performed in MetaDTA (v2.0; Shinyapps, RStudio PBC, Boston, MA, USA) and Review Manager 5.3 (RevMan web; The Cochrane Collaboration, London, UK). Ten articles were included for qualitative synthesis and five for meta-analysis. The pooled diagnostic odds ratio for pulse oximeter (PO), electric pulp tester (EPT), cold test (CT) and heat test (HT) was 628.5, 10.75, 17.24 and 3.47, respectively. Pairwise comparison demonstrated a higher pooled mean sensitivity and specificity with PO compared with EPT. Comparison between PO and CT and between PO and HT also demonstrated a higher pooled mean sensitivity and specificity for PO. Summary points on receiver operating characteristic curves confirmed the ability of PO to correctly screen negatives in presenting patients as compared to EPT, CT and HT but no study was rated as good on quality assessment. PO can be considered as the most accurate diagnostic method as compared to EPT, CT and HT. This review provides information about the reliability and diagnostic accuracy of using pulp vitality and sensibility tests for assessing pulp status.

Oxygen Saturation in Primary Teeth of Individuals With Sickle Cell Disease and Sickle Cell Trait

Purpose

To determine oxygen saturation in the pulp of primary teeth in children with sickle cell disease (SCD) and sickle cell trait (SCT) for establishing the usefulness of pulse oximetry in screening and monitoring of SCD or therapy.

Materials and Methods

A cross-sectional study among 30-60 months children with sickle cell disease (SCD) and sickle cell trait (SCT) compared with healthy children (HbAA). A pulse oximeter (BCI 3301) recorded oxygen saturation on six anterior primary maxillary teeth and on index fingers. Data were analyzed using SPSS version 20.0. Mean oxygen saturation for teeth and fingers was calculated. Comparison of Mean across groups was done using post hoc analysis in one-way ANOVA (Bonferroni test). Pearson correlation coefficient was calculated for mean oxygen saturation on fingers and teeth. Level of significance was set at 0.05.

Results

Altogether 360, 102, and 96 teeth were examined from children with SCD, SCT, and HbAA respectively. 53% of participants were girls. The mean age of participants was 46.3 months ± 9.4 SD. Low mean oxygen saturation (77.5%) was recorded from teeth of children with SCD relative to those with SCT and HbAA (>86%; P = 0.00). There was no statistically significant difference in oxygen saturation on teeth between children with SCT and HbAA. The mean oxygen saturation on fingers was found to be above 97.2% regardless of sickle cell status. There was no correlation between oxygen saturation on teeth and fingers.

Conclusion

Pulse oximeter detected a lower oxygen saturation in dental pulp of primary teeth of participants with SCD (HbSS) relative to those with SCT (HbAS) and HbAA. Oxygen saturation on fingers remained unaffected regardless of sickle cell disease status. Although more studies are needed, our study shows that when other conditions affecting peripheral tissue oxygen delivery are ruled out, the low pulse oximetry in primary teeth may be indicative of SCD. The oximeter may also be useful in monitoring response to SCD therapy targeted at improving oxygen carrying capacity and delivery.

"Oxygen Pheriwala:" An innovative model for SARS-CoV-2 screening in resource-limited settings

The second wave of SARS-CoV-2 infection came as a hypoxic emergency and situation became worse in rural India, where undiagnosed COVID-19 patients died without any diagnosis or intervention. The primary aim of this innovative model was the early diagnosis of suspected SARS-CoV-2 cases, providing empirical treatment and timely referral to appropriate COVID care facilities. Fever was measured with infrared thermometer and oxygen saturation level with pulse oximeter. A total of 8203 people were screened, of which 274 persons were febrile and 69 (25%) were hypoxic too. Sixty-four out of 69 (93%) patients turned COVID-19 positive on reverse transcription-polymerase chain reaction. At the end of 3 weeks, 48/64 (75%) patients were successfully discharged. This model can be easily implemented in resource-limited regions to identify and prioritize the patients not only in this pandemic but also in outbreak of other communicable diseases.

Pulse Oximeter Performance, Racial Inequity, and the Work Ahead

It has long been known that many pulse oximeters function less accurately in patients with darker skin. Reasons for this observation are incompletely characterized and potentially enabled by limitations in existing regulatory oversight. Based on decades of experience and unpublished data, we believe it is feasible to fully characterize, in the public domain, the factors that contribute to missing clinically important hypoxemia in patients with darkly pigmented skin. Here we propose 5 priority areas of inquiry for the research community and actionable changes to current regulations that will help improve oximeter accuracy. We propose that leading regulatory agencies should immediately modify standards for measuring accuracy and precision of oximeter performance, analyzing and reporting performance outliers, diversifying study subject pools, thoughtfully defining skin pigmentation, reporting data transparently, and accounting for performance during low-perfusion states. These changes will help reduce bias in pulse oximeter performance and improve access to safe oximeters.

Experiences From an Implementation Model of ARI Diagnostic Device in Pneumonia Case Management Among Under-5 Children in Peripheral Healthcare Centers in India

OBJECTIVES

To address pneumonia, a major killer of under-5 children in India, a multimodal pulse oximeter was implemented in Health and Wellness Centers. Given the evidence of pulse oximetry in effective pneumonia management and taking into account the inadequate skills of front-line healthcare workers in case management, the device was introduced to help them readily diagnose and treat a child and to examine usability of the device.

DESIGN

The implementation was integrated with the routine OPD of primary health centers for 15 months after healthcare workers were provided with an abridged IMNCI training. Monthly facility data was collected to examine case management with the diagnostic device. Feedback on usefulness of the device was obtained.

SETTING

Health and Wellness Centers (19) of 7 states were selected in consultation with state National Health Mission based on patient footfall.

PARTICIPANTS

Under-5 children presenting with ARI symptoms at the OPD.

RESULTS

Of 4846 children, 0.1% were diagnosed with severe pneumonia and 23% were diagnosed with pneumonia. As per device readings, correct referrals were made of 77.6% of cases of severe pneumonia, and 81% of pneumonia cases were correctly given antibiotics. The Pulse oximeter was highly acceptable among health workers as it helped in timely classification and treatment of pneumonia. It had no maintenance issue and battery was long-lasting.

CONCLUSION

Pulse oximeter implementation was doable and acceptable among health workers. Together with IMNCI training, PO in primary care settings is a feasible approach to provide equitable care to under-5 children.

The Effect of Nail Polish and Henna on the Measures of Pulse Oximeters in Healthy Persons

PURPOSE

The aim of the study was to determine the effects of nail polish and henna on pulse oximetry measurements in healthy individuals.

METHODS

The study was designed as quasi-experimental and cross-sectional study. The population consisted of 682 women studying in a university's nursing department in the Mediterranean region during the academic year of 2016 to 2017. The sample consisted of 103 female students who agreed to participate in the study and met the inclusion criteria. The data were collected using a personal information form prepared in light of the literature. A single layer of nail polish of the same brand was applied; white on the thumb, red on the ring finger, and black on the little finger of the left hand, while henna was applied on the index finger of the left hand of the students. The middle finger was considered as the control group. A portable Nellcor (N-65) pulse oximeter was used for oxygen saturation measurements. The data were analyzed using means, SD, and paired-samples t test.

FINDINGS

There was no statistically significant difference between oxygen saturation measurements of fingers with henna and red nail polish and the control finger (P > .05). However, oxygen saturation levels of fingers with black and white nail polish were lower than the control group's levels, and the difference was statistically significant (P < .05).

CONCLUSIONS

The results demonstrated that white and black nail polish had an impact on oxygen saturation measurements, whereas henna and red nail polish had no effect on the measurements. Based on these findings, nurses may be advised to remove patients' nail polish before measuring oxygen saturation using the finger. In addition, conducting new studies investigating the effects of nail polish, henna, and false nails, which are increasingly used today, on SpO2 values, is suggested.

Prediction of Extubation Failure in COVID-19

BACKGROUND

[Formula: see text] may be a reliable noninvasive alternative to the [Formula: see text] index. Furthermore, the ROX index (ie, the ratio of [Formula: see text] to breathing frequency) has been validated to predict high-flow nasal cannula failure in subjects under spontaneous breathing. However, these indices have not been tested in subjects with COVID-19 receiving invasive mechanical ventilation. This study aims to verify the correlation between both the ROX index and [Formula: see text] with [Formula: see text] and the ratio of [Formula: see text] to breathing frequency, and to determine the accuracy of the indices that use [Formula: see text] for the prediction of extubation failure in subjects with COVID-19.

METHODS

A prospective cohort study was conducted from May 15, 2020, to June 15, 2020, with subjects with COVID-19 on invasive mechanical ventilation. Indices using [Formula: see text] in the formula were compared to those using [Formula: see text]. Additionally, the performance of the indices in predicting extubation failure was evaluated.

RESULTS

This study included 69 subjects age 64.8 ± 14.6 y. There were no differences between the median values of the indices, including between the ROX index and [Formula: see text] to breathing frequency (P = .40) or between [Formula: see text] and [Formula: see text] (P = .83). When comparing the ROX index with the [Formula: see text] index to breathing frequency, they were found to be strongly correlated (R² = 0.75 [95% CI 0.6763-0.8152], P < .001). The comparison of [Formula: see text] with [Formula: see text] revealed R² = 0.70 (95% CI 0.563-0.749, P < .001). The area under the receiver operating characteristic curve for the ROX index to determine extubation failure was 0.74 (P = .01), whereas for [Formula: see text] it was 0.78 (P < .001).

CONCLUSIONS

The indices presented a good correlation in subjects with COVID-19 on invasive mechanical ventilation, and both the ROX index and [Formula: see text] can discriminate extubation failure in this population.

COVID-19-The impact of variable and "low normal" pulse oximetry scores on Oximetry@Home services and clinical pathways: Confounding variables?

COVID‐19 Oximetry@Home services have been commissioned nationally. This allows higher‐risk patients with mild COVID‐19 symptoms to remain at home, being supplied with a Pulse Oximeter to measure their oxygen saturation (SpO₂) two to three times daily for two weeks. Patients record their readings manually or electronically which are monitored by a clinical team. Clinical decisions, using an algorithm, are based on SpO₂ readings in a narrow range with 1–2 point changes potentially affecting care. In this article, we discussed the problem that multiple factors affect SpO₂ readings, and that some “normal” individuals will have “low‐normal” scores at the threshold of clinical management, without any known respiratory problem. We discuss the potential magnitude of this problem based on the associated literature and consider how this will have an impact on the use of the Oximetry@home services, potentially partially confounding their purpose; to reduce face‐to‐face medical care.

Monitoring Symptoms of Infectious Diseases: Perspectives for Printed Wearable Sensors

Infectious diseases possess a serious threat to the world's population, economies, and healthcare systems. In this review, we cover the infectious diseases that are most likely to cause a pandemic according to the WHO (World Health Organization). The list includes COVID-19, Crimean-Congo Hemorrhagic Fever (CCHF), Ebola Virus Disease (EBOV), Marburg Virus Disease (MARV), Lassa Hemorrhagic Fever (LHF), Middle East Respiratory Syndrome (MERS), Severe Acute Respiratory Syndrome (SARS), Nipah Virus diseases (NiV), and Rift Valley fever (RVF). This review also investigates research trends in infectious diseases by analyzing published research history on each disease from 2000-2020 in PubMed. A comprehensive review of sensor printing methods including flexographic printing, gravure printing, inkjet printing, and screen printing is conducted to provide guidelines for the best method depending on the printing scale, resolution, design modification ability, and other requirements. Printed sensors for respiratory rate, heart rate, oxygen saturation, body temperature, and blood pressure are reviewed for the possibility of being used for disease symptom monitoring. Printed wearable sensors are of great potential for continuous monitoring of vital signs in patients and the quarantined as tools for epidemiological screening.

Experiences with use of a pulse oximeter multimodal device in outpatient management of children with Acute Respiratory Infection during Covid pandemic

Background:

While Covid-19 infection rate in children is low, respiratory symptoms are a common mode of presentation which calls for better management of such symptoms. However, ARI case managemnet in primary health settings settings has challenges as health workers lack skills to count respiratory rate and check chest indrawing. To address this multimodal pulse oximeters have been introduced in health and wellness centres of seven states to ease the work of front line health workers. A study was undertaken to understand the usability of the multimodal pulse oximeter during Covid times.

Methods:

A qualitative study was conducted with the aid of indepth interviews among a convenience sample of eleven health care workers from ten health and wellness centres. Interviews were conducted and recorded over phone, after obtaining consent. Transcribed interviews were coded and analysed on a qualitative analysis software. Content analysis was conducted.

Results:

Total children screened during covid lockdown period (April 1-May 31) is 571, those diagnosed with pneumonia and severe pneumonia is 68 and 2. Health care workers were satisfied with pulse oximeter as it helped in timely diagnosis and treatment, and offered protection from possible infection as it mitigated the need for physical contact.

Conclusion:

The multimodal pulse oximeter is well accepted among providers as it is easy to use aiding in timely management of ARI in children. It has an added protection as it's use reduces the need for physical contact. It can be adopted in other HWC and primary health facilities.

Pulp Vitality Testing with a Developed Universal Pulse Oximeter Probe Holder

Background and Objectives An accurate determination of the pulp status is relevant for a proper endodontic diagnosis. Objectives: The aim was to develop a universal pulse oximeter probe holder for measuring the oxygen saturation and to evaluate the use of pulse oximetry as a test for pulp vitality, by comparing the levels of oxygen saturation in the index finger and in the healthy dental pulp. Materials and Methods The universal holder was designed with software and printed with a 3D printer. The study was carried out on 128 healthy teeth. They were divided into eight groups according to tooth type. Ten root canal treated teeth served as a negative control group. For each patient, a pulse oximeter was first applied on the tooth followed by the index finger. The significance level (α) was set at 0.05. Results: The developed and manufactured universal pulse oximeter probe holder was suitable to measure the pulp vitality of all types of teeth. The handle allowed for holding the pulse oximeter on the tooth in parallel, firmly and securely. Significantly higher oxygen saturation was observed in the index finger (97.22%) compared to the dental pulp (93.17%) (p < 0.001). No correlation was observed between the maxillary teeth and index finger oxygen saturation values (r = 0.05, p = 0.72), whereas, between the mandibular teeth and index finger, a positive correlation was detected (r = 0.29, p = 0.02). There were no significant differences in the pulp oxygen saturation values between different teeth groups. Conclusion: The newly developed universal pulse oximeter probe holder is an effective device for pulp vitality testing.

A Single-Center Validation of the Accuracy of a Photoplethysmography-Based Smartwatch for Screening Obstructive Sleep Apnea

BACKGROUND

Obstructive sleep apnea (OSA), the most common upper-airway disease, is closely associated with the risk of cardiovascular diseases. However, the early screening of OSA is a main challenge, relying on polysomnography (PSG) or home sleep apnea test (HSAT) in hospitals. Photoplethysmography (PPG) has been developed as a novel technology for screening of OSA, while the validation of PPG-based smart devices is limited compared to that for PSG or HSAT devices.

OBJECTIVE

This study aimed to investigate the feasibility and validity of a PPG-based smartwatch in the screening of OSA.

METHODS

A total of 119 patients were recruited from the Chinese People's Liberty Army General Hospital (Beijing, China). Among them, 20 patients were assessed for a whole-night sleep study by a smartwatch and PSG simultaneously, as well as 82 cases by a smartwatch and HSAT simultaneously. Using PSG or HSAT as the "gold standard", we compared the accuracy, sensitivity, specificity, negative predictive value (NPV), positive predictive value (PPV), and positive likelihood ratio (+LR) or negative likelihood ratio (-LR) at three apnea hypopnea index (AHI) levels: AHI≥5, AHI≥15, and AHI≥30.

RESULTS

A total of 17/119 patients were excluded from the study due to the poor quality of PPG signals. Among the remaining cases, 83 patients were diagnosed with OSA. Compared to HSAT device, the accuracy, sensitivity, and specificity of the PPG-based smartwatch in predicting moderate-to-severe OSA patients (AHI≥15) were 87.9%, 89.7%, and 86.0%, respectively. Compared to PSG device, the accuracy, sensitivity, and specificity of the PPG-based smartwatch in predicting OSA in patients (AHI≥5) were 81.1%, 76.5%, and 100%, respectively.

CONCLUSION

The PPG-based smartwatch outperformed in terms of detecting OSA; nevertheless, validation in a large-scale population is imperative.

TRIAL REGISTRATION

Chinese Clinical Trial Registry of the International Clinical Trials Registry Platform of the World Health Organization ChiCTR-OOC-17014138; http://www.chictr.org.cn/showprojen.aspx?proj=24191.

Gadgets and Armamentarium of Maxillofacial Surgeons during Coronavirus Pandemic

Introduction:

We all know about the grave situation caused by the novel coronavirus in recent times. Although the maxillofacial surgeons are not at forefront of dealing with the coronavirus directly, they are at increased risk due to their working area on face, mouth, and oral cavity. There is an urgent need to upgrade the already set guidelines and follow them stringently. Any procedure done within the oral cavity is a high-risk procedure and this upgradation is necessary because present means are insufficient to prevent infection from this deadly virus. This article aims to review and discuss all the new gadgets and armamentarium required to deal with patients during and post coronavirus pandemic.

Materials and Methods:

The authors performed a thorough literature search on various armamentarium and new gadgets introduced into the field of dentistry during the coronavirus pandemic worldwide. The relevant armamentarium is discussed under three broad headings, namely, those required before, during and after the procedures for easy understanding.

Results:

A total of 15 gadgets and armamentarium related to oral and maxillofacial surgical practice are named and discussed in the literature review.

Discussion:

We are particularly vulnerable to the transmission of diseases easily both due to the field of interest of work and type of instrumentation. Thus, we need to be extremely cautious about the procedure. Since, the literature is scarce about the sequelae of the coronavirus disease; shift to the automated, contactless gadgets is the way to look forward to a healthy dental practice.

Conclusion:

These gadgets are user friendly for any small dental set-up as well. The choice of these upgraded instruments are prerogative of the individual professionals according to their exclusive practice. Yet, the authors encourage all health care professionals to focus on better training in infection control and cross-contamination.

Wearability Testing of Ambulatory Vital Sign Monitoring Devices: Prospective Observational Cohort Study

Background

Timely recognition of patient deterioration remains challenging. Ambulatory monitoring systems (AMSs) may provide support to current monitoring practices; however, they need to be thoroughly tested before implementation in the clinical environment for early detection of deterioration.

Objective

The objective of this study was to assess the wearability of a selection of commercially available AMSs to inform a future prospective study of ambulatory vital sign monitors in an acute hospital ward.

Methods

Five pulse oximeters (4 with finger probes and 1 wrist-worn only, collecting pulse rates and oxygen saturation) and 2 chest patches (collecting heart rates and respiratory rates) were selected to be part of this study: The 2 chest-worn patches were VitalPatch (VitalConnect) and Peerbridge Cor (Peerbridge); the 4 wrist-worn devices with finger probe were Nonin WristOx2 3150 (Nonin), Checkme O2+ (Viatom Technology), PC-68B, and AP-20 (both from Creative Medical); and the 1 solely wrist-worn device was Wavelet (Wavelet Health). Adult participants wore each device for up to 72 hours while performing usual “activities of daily living” and were asked to score the perceived exertion and perception of pain or discomfort by using the Borg CR-10 scale; thoughts and feelings caused by the AMS using the Comfort Rating Scale (CRS); and to provide general free text feedback. Median and IQRs were reported and nonparametric tests were used to assess differences between the devices’ CRS scores.

Results

Quantitative scores and feedback were collected in 70 completed questionnaires from 20 healthy volunteers, with each device tested approximately 10 times. The Wavelet seemed to be the most wearable device (P<.001) with an overall median (IQR) CRS score of 1.00 (0.88). There were no statistically significant differences in wearability between the chest patches in the CRS total score; however, the VitalPatch was superior in the Attachment section (P=.04) with a median (IQR) score of 3.00 (1.00). General pain and discomfort scores and total percentage of time worn are also reflective of this.

Conclusions

Our results suggest that adult participants prefer to wear wrist-worn pulse oximeters without a probe compressing the fingertip and they prefer to wear a smaller chest patch. A compromise between wearability, reliability, and accuracy should be made for successful and practical integration of AMSs within the hospital environment.

Efficiency of new custom-made pulse oximeter sensor holder in assessment of actual pulp status

Aim

This study aims to assess the diagnostic accuracy of new custom-made pulse oximeter sensor holder in assessment of actual pulp status with three pulp sensibility tests.

Materials and Methods

Seventy-nine single canal teeth requiring endodontic therapy was included in the study. The tooth that was requiring root canal treatment was tested with heat test, cold test, electric pulp test, and pulse oximeter. Between each test, a time period of 2 min was allowed. The response from three pulp sensibility tests and the reading from pulse oximeter were recorded. Following which root canal treatment was performed. The result obtained from four pulp tests were correlated with the clinical finding after access cavity preparation. The data obtained was statistically assessed. Receiver operator characteristic (ROC) curve analysis was performed to assess the efficacy of the pulp tests. In the above statistical tools, the probability value. 05 is considered as significant level.

Results

The overall diagnostic accuracy was found to be significantly higher with pulse oximeter when compared with other three pulp sensibility tests. The ROC curve demonstrates the results obtained from pulse oximeter was found to be more reliable than other pulp tests.

Conclusion

Within the limitation of the study, diagnostic accuracy of pulse oximeter with custom made sensor holder was reliable and accurate in assessment of actual pulp status.

Effect of Prior Health Knowledge on the Usability of Two Home Medical Devices: Usability Study

Background

Studies on the usability of health care devices are becoming more common, although usability standards are not necessarily specified and followed. Yet, there is little knowledge about the impact of the context of use on the usability outcome. It is specified in the usability standard (ISO 9241-11, 2018) of a device that it may be affected by its context of use and especially by the characteristics of its users. Among these, prior health knowledge (ie, knowledge about human body functioning) is crucial. However, no study has shown that prior health knowledge influences the usability of medical devices. 

Objective

Our study aimed to fill this gap by analyzing the relationship between the usability of two home medical devices (soon to be used in the context of ambulatory surgery) and prior health knowledge through an experimental approach.

Methods

For assessing the usability of two home medical devices (blood pressure monitor and pulse oximeter), user tests were conducted among 149 students. A mixed-methods approach (subjective vs objective) using a variety of standard instruments was adopted (direct observation, video analysis, and questionnaires). Participants completed a questionnaire to show the extent of their previous health knowledge and then operated both devices randomly. Efficiency (ie, handling time) and effectiveness (ie, number of handling errors) measures were collected by video analysis. Satisfaction measures were collected by a questionnaire (system usability scale [SUS]). The qualitative observational data were coded using inductive analysis by two independent researchers specialized in cognitive psychology and cognitive ergonomics. Correlational analyses and clusters were performed to test how usability relates to sociodemographic characteristics and prior health knowledge.

Results

The results indicated a lack of usability for both devices. Regarding the blood pressure monitor (137 participants), users made approximately 0.77 errors (SD 1.49), and the mean SUS score was 72.4 (SD 21.07), which is considered “satisfactory.” The pulse oximeter (147 participants) appeared easier to use, but participants made more errors (mean 0.99, SD 0.92), and the mean SUS score was 71.52 (SD 17.29), which is considered “satisfactory.” The results showed a low negative and significant correlation only between the effectiveness of the two devices and previous knowledge (blood pressure monitor: r=−0.191, P=.03; pulse oximeter: r=−0.263, P=.001). More subtly, we experimentally identified the existence of a threshold level (χ²_2,146=10.9, P=.004) for health knowledge to correctly use the pulse oximeter, but this was missing for the blood pressure monitor.

Conclusions

This study has the following two contributions: (1) a theoretical interest highlighting the importance of user characteristics including prior health knowledge on usability outcomes and (2) an applied interest to provide recommendations to designers and medical staff.

Perfusion Index Analysis in Patients Presenting to the Emergency Department Due to Synthetic Cannabinoid Use

Background and Objectives: The perfusion index (PI) indicates the ratio of pulsatile blood flow in peripheral tissue to non-pulsatile blood flow. This study was performed to examine the blood perfusion status of tissues and organs of patients using synthetic cannabinoids (SCs). Materials and Methods: The records of patients aged 17 or over presenting to the adult emergency department due to SC use between 1 January 2016 and 31 December 2017 were examined in this single-center, retrospective, cross-sectional study. Examined factors included time from consumption of SC to presentation to the emergency department, as well as simultaneously determined systolic and diastolic blood pressures, heart rate (beats per min), Glasgow Coma Score (GCS), and PI values. Patients were divided into two groups, A and B, depending on the amount of time that had elapsed between SC consumption and presentation to the emergency department, and statistical data were compared. Results: The mean PI value in Group A was lower than that in Group B. Therefore, we concluded that peripheral tissue and organ blood perfusion is lower in the first 2 h following SC consumption than after 2 h. Systolic, diastolic, and mean arterial blood pressure and mean GCS values were also statistically significantly lower in Group A than in Group B. Conclusions: A decreased PI value may be an early sign of reduced-perfusion organ damage. PI is a practical and useful parameter in the early diagnosis of impaired organ perfusion and in monitoring tissue hypoxia leading to organ failure.

Multi-Site Photoplethysmography Technology for Blood Pressure Assessment: Challenges and Recommendations

Hypertension is one of the most prevalent diseases and is often called the “silent killer” because there are usually no early symptoms. Hypertension is also associated with multiple morbidities, including chronic kidney disease and cardiovascular disease. Early detection and intervention are therefore important. The current routine method for diagnosing hypertension is done using a sphygmomanometer, which can only provide intermittent blood pressure readings and can be confounded by various factors, such as white coat hypertension, time of day, exercise, or stress. Consequently, there is an increasing need for a non-invasive, cuff-less, and continuous blood pressure monitoring device. Multi-site photoplethysmography (PPG) is a promising new technology that can measure a range of features of the pulse, including the pulse transit time of the arterial pulse wave, which can be used to continuously estimate arterial blood pressure. This is achieved by detecting the pulse wave at one body site location and measuring the time it takes for it to reach a second, distal location. The purpose of this review is to analyze the current research in multi-site PPG for blood pressure assessment and provide recommendations to guide future research. In a systematic search of the literature from January 2010 to January 2019, we found 13 papers that proposed novel methods using various two-channel PPG systems and signal processing techniques to acquire blood pressure using multi-site PPG that offered promising results. However, we also found a general lack of validation in terms of sample size and diversity of populations.

Randomised study comparing heart rate measurement in newly born infants using a monitor incorporating electrocardiogram and pulse oximeter versus pulse oximeter alone

AIM

To determine whether IntelliVue (ECG plus Masimo pulse oximeter (PO)) measures heart rate (HR) in low-risk newborns more quickly than Nellcor PO (PO alone).

METHODS

Unmasked parallel group randomised (1:1) study.

RESULTS

We studied 100 infants, 47 randomised to IntelliVue, 53 to Nellcor. Time to first HR was shorter with IntelliVue ECG than Nellcor (median (IQR) 24 (19, 39) vs 48 (36, 69) s, p<0.001). There was no difference in time to display both HR and SpO₂ (52 (47, 76) vs 48 (36, 69) s, p=0.507). IntelliVue PO displayed initial bradycardia more often than the Nellcor (55% vs 6%). Infants monitored with IntelliVue were handled more frequently and for longer.

CONCLUSIONS

IntelliVue ECG displayed HR more quickly than Nellcor PO. IntelliVue PO often displayed initial bradycardia. Infants monitored with IntelliVue were handled more often. Study of ECG in high-risk infants is warranted.

Performance of a novel reusable pediatric pulse oximeter probe

OBJECTIVE

To assess the performance of reusable pulse oximeter probe and microprocessor box combinations, of varying price-points, in the context of a low-income pediatric setting.

METHODS

A prospective, randomized cross-over study comparing time to biologically plausible oxygen saturation (SpO₂ ) between: (1) Lifebox LB-01 probe with Masimo Rad-87 box (L + M) and (2) a weight-appropriate reusable Masimo probe with Masimo Rad-87 box (M + M). A post hoc secondary analysis comparison with historical usability testing data with the Lifebox LB-01 probe and Lifebox V1.5 box (L + L) was also conducted. Participants, children aged 0 to 35 months, were recruited from pediatric wards and outpatient clinics in the central region of Malawi. The primary outcome was time taken to achieve a biologically plausible SpO ₂ measurement, compared using t tests for equivalence.

RESULTS

We recruited 572 children. Plausible SpO₂ measurements were obtained in less than 1 minute, 71%, 70%, and 63% for the M + M, L + M, and L + L combinations, respectively. A similar pattern was seen for less than 2 minutes, however, this effect disappeared at less than 5 minutes with 96%, 96%, and 95% plausible measurements. Using a ±10 second threshold for equivalence, we found L + M and M + M to be equivalent, but were under-powered to assess equivalence for L + L.

CONCLUSIONS

The novel reusable pediatric Lifebox probe can achieve a quality SpO₂ measurement within a pragmatic time range of weight-appropriate Masimo equivalent probes. Further research, which considers the cost of the devices, is needed to assess the added value of sophisticated motion tolerance software.

How Effective Is Pulse Arrival Time for Evaluating Blood Pressure? Challenges and Recommendations from a Study Using the MIMIC Database

Cardiovascular disease (CVD) is the number one cause of non-infectious morbidity and mortality in the world. The detection, measurement, and management of high blood pressure play an essential role in the prevention and control of CVDs. However, owing to the limitations and discomfort of traditional blood pressure (BP) detection techniques, many new cuff-less blood pressure approaches have been proposed and explored. Most of these involve arterial wave propagation theory, which is based on pulse arrival time (PAT), the time interval needed for a pulse wave to travel from the heart to some distal place on the body, such as the finger or earlobe. For this study, the Medical Information Mart for Intensive Care (MIMIC) database was used as a benchmark for PAT analysis. Many researchers who use the MIMIC database make the erroneous assumption that all the signals are synchronized. Therefore, we decided to investigate the calculation of PAT intervals in the MIMIC database and check its usefulness for evaluating BP. Our findings have important implications for the future use of the MIMIC database, especially for BP evaluation.

Sleep-Disordered Breathing Is a Stronger Risk Factor for Proliferative Diabetic Retinopathy than Metabolic Syndrome and the Number of Its Individual Components

PURPOSE

To evaluate whether the features of sleep-disordered breathing (SDB) are stronger independent factors for proliferative diabetic retinopathy (PDR) compared to the incidence of metabolic syndrome (MetS) and the number of its individual components.

METHODS

We studied a cross-sectional total of 132 patients with type 2 diabetes. Thirty-nine patients had non-proliferative diabetic retinopathy (NPDR) and 93 patients had PDR. Pulse oximetry was conducted, and the patients' mean oxygen saturation (mean SpO2%) and 4% oxygen desaturation index (4% ODI times/hour) were evaluated. We compared the SDB and MetS variables between the NPDR and PDR patients. A logistic regression analysis was used to determine the independent factors for the diagnosis of PDR.

RESULTS

The MetS diagnosis was made significantly more often in the PDR group (p = 0.04). The number of individual MetS components was significantly greater in the PDR group compared to the NPDR group (p = 0.01). The mean SpO2 of the NPDR group was not significantly different from that of the PDR group. The 4% ODI in the NPDR group was significantly lower than that in the PDR group (p = 0.01). The logistic regression analysis using the prevalence of MetS and the number of MetS components revealed that younger age and high 4%ODI value were independent factors contributing to the diagnosis of PDR.

CONCLUSION

Our findings confirmed that compared to MetS and the number of its individual components, SDB may be a factor contributing to the progression to PDR. However, further careful longitudinal validation studies are needed.

Comparison of the anesthetic effects of 2,2,2-tribromoethanol on ICR mice derived from three different sources

This study was conducted to compare the anesthetic effects of 2,2,2-tribromoethanol (TBE, Avertin®) in ICR mice obtained from three different sources. TBE (2.5%) was intraperitoneally injected at three doses: high-dose group (500 mg/kg), intermediate-dose group (250 mg/kg), and low-dose group (125 mg/kg). Anesthesia time, recovery time, end-tidal peak CO₂ (ETCO₂), mean arterial blood pressure, heart rate, oxygen saturation (SpO₂), body temperature, pH, PCO₂, and PO₂ of the arterial blood were measured. Stable anesthesia was induced by all doses of TBE and the anesthesia time was maintained exhibited dose dependency. No significant differences in anesthetic duration were found among the three different strains. However, the anesthesia time was longer in female than in male mice, and the duration of anesthesia was significantly longer in female than in male mice in the high-dose group. The recovery time was significantly longer for female than male mice in the intermediate- and high-dose groups. In the ICR strains tested, there were no significant differences in the mean arterial blood pressure, SPO₂, arterial blood PCO₂, and PO₂, which decreased after TBE anesthesia, or in heart rate and ETCO₂, which increased after TBE anesthesia. In addition, body temperature, blood biochemical markers, and histopathological changes of the liver, kidney, and lung were not significantly changed by TBE anesthesia. These results suggested that ICR mice from different sources exhibited similar overall responses to a single exposure to TBE anesthesia. In conclusion, TBE is a useful drug that can induce similar anesthetic effects in three different strains of ICR mice.

Photoplethysmography and Deep Learning: Enhancing Hypertension Risk Stratification

Blood pressure is a basic physiological parameter in the cardiovascular circulatory system. Long-term abnormal blood pressure will lead to various cardiovascular diseases, making the early detection and assessment of hypertension profoundly significant for the prevention and treatment of cardiovascular diseases. In this paper, we investigate whether or not deep learning can provide better results for hypertension risk stratification when compared to the classical signal processing and feature extraction methods. We tested a deep learning method for the classification and evaluation of hypertension using photoplethysmography (PPG) signals based on the continuous wavelet transform (using Morse) and pretrained convolutional neural network (using GoogLeNet). We collected 121 data recordings from the Multiparameter Intelligent Monitoring in Intensive Care (MIMIC) Database, each containing arterial blood pressure (ABP) and photoplethysmography (PPG) signals. The ABP signals were utilized to extract blood pressure category labels, and the PPG signals were used to train and test the model. According to the seventh report of the Joint National Committee, blood pressure levels are categorized as normotension (NT), prehypertension (PHT), and hypertension (HT). For the early diagnosis and assessment of HT, the timely detection of PHT and the accurate diagnosis of HT are significant. Therefore, three HT classification trials were set: NT vs. PHT, NT vs. HT, and (NT + PHT) vs. HT. The F-scores of these three classification trials were 80.52%, 92.55%, and 82.95%, respectively. The tested deep method achieved higher accuracy for hypertension risk stratification when compared to the classical signal processing and feature extraction method. Additionally, the method achieved comparable results to another approach that requires electrocardiogram and PPG signals.

Performance, Acceptability, and Usability of Respiratory Rate Timers and Pulse Oximeters When Used by Frontline Health Workers to Detect Symptoms of Pneumonia in Sub-Saharan Africa and Southeast Asia: Protocol for a Two-Phase, Multisite, Mixed-Methods Trial

Background

Pneumonia is one of the leading causes of death in children aged under 5 years in both sub-Saharan Africa and Southeast Asia. The current diagnostic criterion for pneumonia is based on the increased respiratory rate (RR) in children with cough or difficulty breathing. Low oxygen saturation, measured using pulse oximeters, is indicative of severe pneumonia. Health workers often find it difficult to accurately count the number of breaths, and the current RR counting devices are often difficult to use or unavailable. Nonetheless, improved counting devices and low-cost pulse oximeters are now available on the market.

Objective

The objective of our study was to identify the most accurate, usable, and acceptable devices for the diagnosis of pneumonia symptoms by community health workers and first-level health facility workers or frontline health workers in resource-poor settings.

Methods

This was a multicenter, prospective, two-stage, observational study to assess the performance and usability or acceptability of 9 potential diagnostic devices when used to detect symptoms of pneumonia in the hands of frontline health workers. Notably, 188 possible devices were ranked and scored, tested for suitability in a laboratory, and 5 pulse oximeters and 4 RR timers were evaluated for usability and performance by frontline health workers in hospital, health facility, and community settings. The performance was evaluated against 2 references over 3 months in Cambodia, Ethiopia, South Sudan, and Uganda. Furthermore, acceptability and usability was subsequently evaluated using both qualitative and quantitative methodologies in routine practice, over 3 months, in the 4 countries.

Results

This project was funded in 2014, and data collection has been completed. Data analysis is currently under way, and the first results are expected to be submitted for publication in 2018.

Conclusions

This is the first large-scale evaluation of tools to detect symptoms of pneumonia at the community level. In addition, selecting an appropriate reference standard against which the devices were measured was challenging given the lack of existing standards and differences of opinions among experts. The findings from this study will help create a standardized and validated protocol for future studies and support further comparative testing of diagnostic devices in these settings.

Trial Registration

Australian New Zealand Clinical Trials Registry ACTRN12615000348550; https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=367306&isReview=true (Archived by Website at http://www.webcitation.org/72OcvgBcf)

International Registered Report Identifier (IRRID)

RR1-10.2196/10191

Can Photoplethysmography Replace Arterial Blood Pressure in the Assessment of Blood Pressure?

Arterial Blood Pressure (ABP) and photoplethysmography (PPG) are both useful techniques to monitor cardiovascular status. Though ABP monitoring is more widely employed, this procedure of signal acquisition whether done invasively or non-invasively may cause inconvenience and discomfort to the patients. PPG, however, is simple, noninvasive, and can be used for continuous measurement. This paper focuses on analyzing the similarities in time and frequency domains between ABP and PPG signals for normotensive, prehypertensive and hypertensive subjects and the feasibility of the classification of subjects considering the results of the analysis performed. From a database with 120 records of ABP and PPG, each 120 s in length, the records where separated into epochs taking into account 10 heartbeats, and the following statistical measures were performed: Correlation (r), Coherence (COH), Partial Coherence (pCOH), Partial Directed Coherence (PDC), Directed Transfer Function (DTF), Full Frequency Directed Transfer Function (ffDTF) and Direct Directed Transfer Function (dDTF). The correlation coefficient was r > 0.9 on average for all groups, indicating a strong morphology similarity. For COH and pCOH, coherence (linear correlation in frequency domain) was found with significance (p < 0.01) in differentiating between normotensive and hypertensive subjects using PPG signals. For the dataset at hand, only two synchrony measures are able to convincingly distinguish hypertensive subjects from normotensive control subjects, i.e., ffDTF and dDTF. From PDC, DTF, ffDTF, and dDTF, a consistent, a strong significant causality from ABP→PPG was found. When all synchrony measures were combined, an 87.5 % accuracy was achieved to detect hypertension using a Neural Network classifier, suggesting that PPG holds most informative features that exist in ABP.

Childhood pneumonia diagnostics: community health workers' and national stakeholders' differing perspectives of new and existing aids

Background: Pneumonia heavily contributes to global under-five mortality. Many countries use community case management to detect and treat childhood pneumonia. Community health workers (CHWs) have limited tools to help them assess signs of pneumonia. New respiratory rate (RR) counting devices and pulse oximeters are being considered for this purpose.

Objective: To explore perspectives of CHWs and national stakeholders regarding the potential usability and scalability of seven devices to aid community assessment of pneumonia signs.

Design: Pile sorting was conducted to rate the usability and scalability of 7 different RR counting aids and pulse oximeters amongst 16 groups of participants. Following each pile-sorting session, a focus group discussion (FGD) explored participants’ sorting rationale. Purposive sampling was used to select CHWs and national stakeholders with experience in childhood pneumonia and integrated community case management (iCCM) in Cambodia, Ethiopia, Uganda and South Sudan. Pile-sorting data were aggregated for countries and participant groups. FGDs were audio recorded and transcribed verbatim. Translated FGDs transcripts were coded in NVivo 10 and analysed using thematic content analysis. Comparative analysis was performed between countries and groups to identify thematic patterns.

Results: CHWs and national stakeholders across the four countries perceived the acute respiratory infection (ARI) timer and fingertip pulse oximeter as highly scalable and easy for CHWs to use. National stakeholders were less receptive to new technologies. CHWs placed greater priority on device acceptability to caregivers and children. Both groups felt that heavy reliance on electricity reduced potential scalability and usability in rural areas. Device simplicity, affordability and sustainability were universally valued.

Conclusions: CHWs and national stakeholders prioritise different device characteristics according to their specific focus of work. The views of all relevant stakeholders, including health workers, policy makers, children and parents, should be considered in future policy decisions, research and development regarding suitable pneumonia diagnostic aids for community use.