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Scientific Reports Sep 2022In patients with kidney failure treated by hemodialysis, intradialytic arterial oxygen saturation (SaO) time series present intermittent high-frequency high-amplitude...
In patients with kidney failure treated by hemodialysis, intradialytic arterial oxygen saturation (SaO) time series present intermittent high-frequency high-amplitude oximetry patterns (IHHOP), which correlate with observed sleep-associated breathing disturbances. A new method for identifying such intermittent patterns is proposed. The method is based on the analysis of recurrence in the time series through the quantification of an optimal recurrence threshold ([Formula: see text]). New time series for the value of [Formula: see text] were constructed using a rolling window scheme, which allowed for real-time identification of the occurrence of IHHOPs. The results for the optimal recurrence threshold were confronted with standard metrics used in studies of obstructive sleep apnea, namely the oxygen desaturation index (ODI) and oxygen desaturation density (ODD). A high correlation between [Formula: see text] and the ODD was observed. Using the value of the ODI as a surrogate to the apnea-hypopnea index (AHI), it was shown that the value of [Formula: see text] distinguishes occurrences of sleep apnea with great accuracy. When subjected to binary classifiers, this newly proposed metric has great power for predicting the occurrences of sleep apnea-related events, as can be seen by the larger than 0.90 AUC observed in the ROC curve. Therefore, the optimal threshold [Formula: see text] from recurrence analysis can be used as a metric to quantify the occurrence of abnormal behaviors in the arterial oxygen saturation time series.
Topics: Humans; Oximetry; Oxygen; Polysomnography; Sleep Apnea Syndromes; Sleep Apnea, Obstructive
PubMed: 36163364
DOI: 10.1038/s41598-022-20493-0 -
Biomedical Instrumentation & Technology May 2021Following a merger of two children's hospitals, leadership discovered a considerable utilization volume of single-use sensors that was associated with declining hospital...
BACKGROUND
Following a merger of two children's hospitals, leadership discovered a considerable utilization volume of single-use sensors that was associated with declining hospital reimbursements. This discovery resulted in the establishment of a new sensor management strategy, the goal of which was to decrease costs and waste associated with disposable pulse oximetry sensors.
IMPLEMENTATION
The sensor management strategy involved using replacement tapes with single-patient-use pulse oximeter sensors instead of the current practice of reprobing with a new sensor. A 60% utilization goal was set, with the focus shifted from sensors used per patient to replacement tapes per sensor.
RESULTS
The implementation of a new sensor management strategy between the years 2006 and 2019 in a hospital system decreased sensor volume by more than 780,000 sensors and realized a cost avoidance of more than 7 million dollars.
CONCLUSION
A sensor management strategy can substantially reduce the cost and medical waste commonly associated with the use of disposable, single-patient pulse oximetry sensors.
Topics: Child; Hospitals; Humans; Oximetry; Oxygen
PubMed: 34019076
DOI: 10.2345/0899-8205-55.2.59 -
Scientific Reports Sep 2023Oxygenation is a crucial indicator of tissue viability and function. Oxygen tension ([Formula: see text]), i.e. the amount of molecular oxygen present in the tissue is a...
Oxygenation is a crucial indicator of tissue viability and function. Oxygen tension ([Formula: see text]), i.e. the amount of molecular oxygen present in the tissue is a direct result of supply (perfusion) and consumption. Thus, measurement of [Formula: see text] is an effective method to monitor tissue viability. However, tissue oximetry sensors commonly used in clinical practice instead rely on measuring oxygen saturation ([Formula: see text]), largely due to the lack of reliable, affordable [Formula: see text] sensing solutions. To address this issue we present a proof-of-concept design and validation of a low-cost, lifetime-based oxygen sensing fiber. The sensor consists of readily-available off-the shelf components such as a microcontroller, a light-emitting diode (LED), an avalanche photodiode (APD), a temperature sensor, as well as a bright in-house developed porphyrin molecule. The device was calibrated using a benchtop setup and evaluated in three in vivo animal models. Our findings show that the new device design in combination with the bright porphyrin has the potential to be a useful and accurate tool for measuring [Formula: see text] in tissue, while also highlighting some of the limitations and challenges of oxygen measurements in this context.
Topics: Animals; Blood Gas Analysis; Fiber Optic Technology; Oximetry; Oxygen; Porphyrins
PubMed: 37679415
DOI: 10.1038/s41598-023-41917-5 -
Indian Pediatrics Dec 2021
Topics: Child; Humans; Oximetry; Oxygen; Oxygen Saturation; Shock, Septic
PubMed: 34939579
DOI: No ID Found -
Sensors (Basel, Switzerland) Jan 2022Oxyhemoglobin saturation by pulse oximetry (SpO) has always played an important role in the diagnosis of symptoms. Considering that the traditional SpO measurement has a...
Oxyhemoglobin saturation by pulse oximetry (SpO) has always played an important role in the diagnosis of symptoms. Considering that the traditional SpO measurement has a certain error due to the number of wavelengths and the algorithm and the wider application of machine learning and spectrum combination, we propose to use 12-wavelength spectral absorption measurement to improve the accuracy of SpO measurement. To investigate the multiple spectral regions for deep learning for SpO measurement, three datasets for training and verification were built, which were constructed over the spectra of first region, second region, and full region and their sub-regions, respectively. For each region under the procedures of optimization of our model, a thorough of investigation of hyperparameters is proceeded. Additionally, data augmentation is preformed to expand dataset with added noise randomly, increasing the diversity of data and improving the generalization of the neural network. After that, the established dataset is input to a one dimensional convolution neural network (1D-CNN) to obtain a measurement model of SpO. In order to enhance the model accuracy, GridSearchCV and Bayesian optimization are applied to optimize the hyperparameters. The optimal accuracies of proposed model optimized by GridSearchCV and Bayesian Optimization is 89.3% and 99.4%, respectively, and trained with the dataset at the spectral region of six wavelengths including 650 nm, 680 nm, 730 nm, 760 nm, 810 nm, 860 nm. The total relative error of the best model is only 0.46%, optimized by Bayesian optimization. Although the spectral measurement with more features can improve the resolution ability of the neural network, the results reveal that the training with the dataset of the shorter six wavelength is redundant. This analysis shows that it is very important to construct an effective 1D-CNN model area for spectral measurement using the appropriate spectral ranges and number of wavelengths. It shows that our proposed 1D-CNN model gives a new and feasible approach to measure SpO based on multi-wavelength.
Topics: Bayes Theorem; Deep Learning; Machine Learning; Neural Networks, Computer; Oximetry
PubMed: 35009870
DOI: 10.3390/s22010328 -
The Lancet. Global Health Mar 2022
Topics: Developing Countries; Humans; Income; Oximetry; Oxygen; Poverty
PubMed: 35180401
DOI: 10.1016/S2214-109X(22)00025-0 -
Archives of Disease in Childhood Mar 2021Pneumonia is the largest cause of child deaths in low-income countries. Lack of availability of oxygen in small rural hospitals results in avoidable deaths and... (Clinical Trial)
Clinical Trial Comparative Study
BACKGROUND
Pneumonia is the largest cause of child deaths in low-income countries. Lack of availability of oxygen in small rural hospitals results in avoidable deaths and unnecessary and unsafe referrals.
METHOD
We evaluated a programme for improving reliable oxygen therapy using oxygen concentrators, pulse oximeters and sustainable solar power in 38 remote health facilities in nine provinces in Papua New Guinea. The programme included a quality improvement approach with training, identification of gaps, problem solving and corrective measures. Admissions and deaths from pneumonia and overall paediatric admissions, deaths and referrals were recorded using routine health information data for 2-4 years prior to the intervention and 2-4 years after. Using Poisson regression we calculated incidence rates (IRs) preintervention and postintervention, and incidence rate ratios (IRR).
RESULTS
There were 18 933 pneumonia admissions and 530 pneumonia deaths. Pneumonia admission numbers were significantly lower in the postintervention era than in the preintervention era. The IRs for pneumonia deaths preintervention and postintervention were 2.83 (1.98-4.06) and 1.17 (0.48-1.86) per 100 pneumonia admissions: the IRR for pneumonia deaths was 0.41 (0.24-0.71, p<0.005). There were 58 324 paediatric admissions and 2259 paediatric deaths. The IR for child deaths preintervention and postintervention were 3.22 (2.42-4.28) and 1.94 (1.23-2.65) per 100 paediatric admissions: IRR 0.60 (0.45-0.81, p<0.005). In the years postintervention period, an estimated 348 lives were saved, at a cost of US$6435 per life saved and over 1500 referrals were avoided.
CONCLUSIONS
Solar-powered oxygen systems supported by continuous quality improvement can be achieved at large scale in rural and remote hospitals and health care facilities, and was associated with reduced child deaths and reduced referrals. Variability of effectiveness in different contexts calls for strengthening of quality improvement in rural health facilities.
TRIAL REGISTRATION NUMBER
ACTRN12616001469404.
Topics: Adolescent; Child; Child, Preschool; Cost-Benefit Analysis; Developing Countries; Health Facilities; Hospitalization; Hospitals, Rural; Humans; Incidence; Infant; Infant, Newborn; Mortality; Oximetry; Oxygen; Oxygen Inhalation Therapy; Papua New Guinea; Pneumonia; Program Evaluation; Quality Improvement; Solar Energy
PubMed: 33067311
DOI: 10.1136/archdischild-2020-320107 -
BMJ Global Health Nov 2021Acute fever is a common presenting symptom in low/middle-income countries (LMICs) and is strongly associated with sepsis. Hypoxaemia predicts disease severity in such...
BACKGROUND
Acute fever is a common presenting symptom in low/middle-income countries (LMICs) and is strongly associated with sepsis. Hypoxaemia predicts disease severity in such patients but is poorly detected by clinical examination. Therefore, including pulse oximetry in the assessment of acutely febrile patients may improve clinical outcomes in LMIC settings.
METHODS
We systematically reviewed studies of any design comparing one group where pulse oximetry was used and at least one group where it was not. The target population was patients of any age presenting with acute febrile illness or associated syndromes in LMICs. Studies were obtained from searching PubMed, EMBASE, CABI Global Health, Global Index Medicus, CINAHL, Cochrane CENTRAL, Web of Science and DARE. Further studies were identified through searches of non-governmental organisation websites, snowballing and input from a Technical Advisory Panel. Outcomes of interest were diagnosis, management and patient outcomes. Study quality was assessed using the Cochrane Risk of Bias 2 tool for Cluster Randomised Trials and Risk of Bias in Non-randomized Studies of Interventions tools, as appropriate.
RESULTS
Ten of 4898 studies were eligible for inclusion. Their small number and heterogeneity prevented formal meta-analysis. All studies were in children, eight only recruited patients with pneumonia, and nine were conducted in Africa or Australasia. Six were at serious risk of bias. There was moderately strong evidence for the utility of pulse oximetry in diagnosing pneumonia and identifying severe disease requiring hospital referral. Pulse oximetry used as part of a quality-assured facility-wide package of interventions may reduce pneumonia mortality, but studies assessing this endpoint were at serious risk of bias.
CONCLUSIONS
Very few studies addressed this important question. In LMICs, pulse oximetry may assist clinicians in diagnosing and managing paediatric pneumonia, but for the greatest impact on patient outcomes should be implemented as part of a health systems approach. The evidence for these conclusions is not widely generalisable and is of poor quality.
Topics: Africa; Child; Developing Countries; Humans; Income; Oximetry
PubMed: 34824136
DOI: 10.1136/bmjgh-2021-007282 -
Journal of Global Health 2022Hypoxaemia is one of the strongest predictors of mortality among children with pneumonia. It can be identified through pulse oximetry instantaneously, which is a... (Observational Study)
Observational Study
Success and time implications of SpO measurement through pulse oximetry among hospitalised children in rural Bangladesh: Variability by various device-, provider- and patient-related factors.
BACKGROUND
Hypoxaemia is one of the strongest predictors of mortality among children with pneumonia. It can be identified through pulse oximetry instantaneously, which is a non-invasive procedure but can be influenced by factors related to the specific measuring device, health provider and patient. Following WHO's global recommendation in 2014, Bangladesh decided to introduce pulse oximetry in paediatric outpatient services, ie, the Integrated Management of Childhood Illness (IMCI) services in 2019. A national committee updated the existing IMCI implementation package and decided to test it by assessing the pulse oximetry performance of different types of assessors in real-life inpatient settings.
METHODS
We adopted an observational design and conducted a technology assessment among children admitted to a rural district hospital. Eleven nurses and seven paramedics received one-day training on pulse oximetry as assessors. Each assessor performed at least 30 pulse oximetry measurements on children with two types of handheld devices. The primary outcome of interest was obtaining a successful measurement of SpO2, defined as observing a stable (±1%) reading for at least 10 seconds. Performance time, ie, time taken to obtain a successful measurement of SpO was considered the secondary outcome of interest. In addition, we used Generalized Estimating Equation to assess the effect of different factors on the pulse oximetry performance.
RESULTS
The assessors obtained successful measurements of SpO in all attempts (n = 1478) except one. The median time taken was 30 (interquartile range (IQR) = 22-42) seconds, and within 60 seconds, 92% of attempts were successful. The odds of obtaining a successful measurement within 60 seconds were 7.3 (95% confidence interval (CI) = 3.7-14.2) times higher with a Masimo device than a Lifebox device. Similarly, assessors aged >25 years were 4.8 (95% CI = 1.2, 18.6) times more likely to obtain a successful measurement within 60 seconds. The odds of obtaining a successful measurement was 2.6 (95% CI = 1.6, 4.2) times higher among children aged 12-59 months compared to 2-11 months.
CONCLUSIONS
Our study indicated that assessors could achieve the necessary skills to perform pulse oximetry successfully in real-life inpatient settings through a short training module, with some effect of device-, provider- and patient-related factors. The National IMCI Programme of Bangladesh can use these findings for finalising the national IMCI training modules and implementation package incorporating the recommendation of using pulse oximetry for childhood pneumonia assessment.
Topics: Bangladesh; Child; Child, Hospitalized; Humans; Hypoxia; Oximetry; Pneumonia
PubMed: 35493782
DOI: 10.7189/jogh.12.04036 -
Pulmonology 2022
Topics: Humans; Noninvasive Ventilation; Oximetry
PubMed: 35339420
DOI: 10.1016/j.pulmoe.2022.02.008