Pulse oximetry as a fifth pediatric vital sign

Accuracy of Apple Watch to Measure Cardiovascular Indices in Patients with Chronic Diseases: A Cross Sectional Study

Background

The validity of the Apple Watch to measure the heart rate (HR) and oxygen saturation (Spo2) for patients with chronic diseases such as diabetes mellitus (DM), dyslipidemia, and hypertension is still unclear. Therefore, this study aims to investigate the accuracy of the Apple Watch in measuring the Spo2 and HR in patients with chronic diseases.

Methods

Forty-one patients with chronic diseases, including 20 with hypertension, 10 with diabetes, and 11 with dyslipidemia, completed a cross-sectional study. All participants used the Apple Watch against the Polar chest strap and the pulse oximeter at rest and during moderate intensity exercise sessions to measure HR and the SpO2 at rest for 5 minutes, during exercise for 16 minutes, and followed by 3 minutes of rest. The HR was measured during all previous periods, but evaluation of the Spo2 included 5 measures, done only before and after exercise, with a minute interval between each measure.

Results

Overall, a strong correlation exists between measuring the SpO2 using the Apple Watch against the pulse oximeter (Contec) at rest (r = 0.92, p < 0.001) and after exercise (r = 0.86, p < 0.001) in all patients. The HR had a very strong correlation between the Apple Watch and the Polar chest strap (r = 0.99, p < 0.001) in all patients. There was no significant difference (p = 0.76) between the twenty-seven white and fourteen brown-skinned patients.

Conclusion

The Apple Watch is valid to measure the HR and SpO2 in patients with chronic diseases.

Clinical Trial Registration No

NCT05271864.

Arterial Oxygen Saturation: A Vital Sign?

ABSTRACT

The physical examination is a key part of a continuum that extends from the history of the present illness to the therapeutic outcome. An understanding of the pathophysiological mechanism behind a physical sign is essential for arriving at the correct diagnosis. Early detection of deteriorating physical/vital signs and their appropriate interpretation is thus the key to achieve correct and timely management. By definition, vital signs are "the signs of life that may be monitored or measured, namely pulse rate, respiratory rate, body temperature, and blood pressure." Vital signs are the simplest, cheapest and probably the most inexpensive information gathered bedside in outpatient or hospitalized patients. The pulse oximeter was introduced in the 1980s. It is an accurate and non-invasive method for the measurement of arterial hemoglobin oxygen saturation (SaO2). Pulse oximetry-based arterial oxygen saturation can be effectively used bedside in in-hospital and ambulatory patients with diagnosed or suspected lung disease. The present pandemic of COVID-19 should be considered as a wake-up call. Articles related to arterial oxygen saturation and its importance as a vital sign in patient care were searched online especially in PubMed. Available studies were studied in full length and data was extracted. Discussion: A. Clinical Utility of Oxygen Saturation Monitoring: There are many studies reporting the clinical applicability and usefulness of pulse oximetry in the early detection of hypoxemic events during intraoperative and postoperative periods. B. Role of clinical expertise accompanied by knowledge of physiology: A diagnostic sign is useful only if it is interpreted accurately and applied appropriately while evaluating a patient. The World Health Organisation also appreciates these facts and published "The WHO Pulse Oximetry Training Manual." Understanding the physiology behind and overcoming limitations of the diagnostic sign by clinical expertise is important. While using pulse oximetry, a clinician needs to keep in mind the sigmoidal nature of the oxygen-Hb dissociation curve. Considering these benefits of SaO2 measurement, there have been several references in the past to consider oxygen saturation as the fifth vital sign. In the present pandemic oxygen saturation i.e., SpO2 (arterial oxygen saturation) measured by pulse oxymeter, has been the single most important warning and prognostic sign be it for households, offices, street vendors, hospitals or governments. Measurement of trends of SaO2 added with respiratory rate will provide clinicians with a holistic overview of respiratory functions and multidimensional conditions associated with hypoxemia.

The role of oxygen in the development and treatment of bronchopulmonary dysplasia

Oxygen (O2) is crucial for both the development and treatment of one of the most important consequences of prematurity: bronchopulmonary dysplasia (BPD). In fetal life, the hypoxic environment is important for alveolar development and maturation. After birth, O2 becomes a double-edged sword. While O2 is needed to prevent hypoxia, it also causes oxidative stress leading to a plethora of morbidities, including retinopathy and BPD. The advent of continuous O2 monitoring with pulse oximeters has allowed clinicians to recognize the narrow therapeutic margins of oxygenation for the preterm infant, but more knowledge is needed to understand what these ranges are at different stages of the preterm infant's life, including at birth, in the neonatal intensive care unit and after hospital discharge. Future research, especially in innovative technologies such as automated O2 control and remote oximetry, will improve the understanding and treatment of the O2 needs of infants with BPD.

A Feeding Adequacy Scale for Children With Bronchiolitis: Prospective Multicenter Study

OBJECTIVES

To determine the measurement properties of the Feeding Adequacy Scale (FAS) in young children hospitalized with bronchiolitis.

METHODS

Multicenter cohort study of infants hospitalized with bronchiolitis at children's and community hospitals in Ontario, Canada. Caregivers and nurses completed the FAS, a 10-cm visual analog scale anchored by "not feeding at all" (score 0) and "feeding as when healthy" (score 10). The main outcome measures were feasibility, reliability, validity, and responsiveness of the FAS.

RESULTS

A total of 228 children were included with an average (SD) age of 6.3 (5.4) months. Completing the FAS was feasible for caregivers and nurses, with no floor or ceiling effects. Test-retest reliability was moderate for caregivers (intraclass correlation coefficient [ICC] 2,1 0.73; 95% confidence interval [CI] 0.63-0.80) and good for nurses (ICC 2,1 0.75; 95% CI 0.62-0.83). Interrater reliability between 1 caregiver and 1 nurse was moderate (ICC 1,1 0.55; 95% CI 0.45-0.64). For construct validity, the FAS was negatively associated with length of hospital stay and positively associated with both caregiver and nurse readiness for discharge scores (P values <.0001). The FAS demonstrated clinical improvement from the first FAS score at admission to the last FAS score at discharge, with significant differences between scores for both caregivers and nurses (P values for paired t test <.0001).

CONCLUSIONS

These results provide evidence of the feasibility, reliability, validity, and responsiveness of caregiver-completed and nurse-completed FAS as a measure of feeding adequacy in children hospitalized with bronchiolitis.

Pulse oximetry values from 33,080 participants in the Apple Heart & Movement Study

Wearable devices that include pulse oximetry (SpO₂) sensing afford the opportunity to capture oxygen saturation measurements from large cohorts under naturalistic conditions. We report here a cross-sectional analysis of 72 million SpO₂ values collected from 33,080 individual participants in the Apple Heart and Movement Study, stratified by age, sex, body mass index (BMI), home altitude, and other demographic variables. Measurements aggregated by hour of day into 24-h SpO₂ profiles exhibit similar circadian patterns for all demographic groups, being approximately sinusoidal with nadir near midnight local time, zenith near noon local time, and mean 0.8% lower saturation during overnight hours. Using SpO₂ measurements averaged for each subject into mean nocturnal and daytime SpO₂ values, we employ multivariate ordinary least squares regression to quantify population-level trends according to demographic factors. For the full cohort, regression coefficients obtained from models fit to daytime SpO₂ are in close quantitative agreement with the corresponding values from published reference models for awake arterial oxygen saturation measured under controlled laboratory conditions. Regression models stratified by sex reveal significantly different age- and BMI-dependent SpO₂ trends for females compared with males, although constant terms and regression coefficients for altitude do not differ between sexes. Incorporating categorical variables encoding self-reported race/ethnicity into the full-cohort regression models identifies small but statistically significant differences in daytime SpO₂ (largest coefficient corresponding to 0.13% lower SpO₂, for Hispanic study participants compared to White participants), but no significant differences between groups for nocturnal SpO₂. Additional stratified analysis comparing regression models fit independently to subjects in each race/ethnicity group is suggestive of small differences in age- and sex-dependent trends, but indicates no significant difference in constant terms between any race/ethnicity groups for either daytime or nocturnal SpO₂. The large diverse study population and study design employing automated background SpO₂ measurements spanning the full 24-h circadian cycle enables the establishment of healthy population reference trends outside of clinical settings.

Pulse oximetry: why oxygen saturation is still not a part of standard pediatric guidelines in low-and-middle-income countries (LMICs)

BACKGROUND

With the high frequency of acute respiratory infections in children worldwide, particularly so in low-resource countries, the development of effective diagnostic support is crucial. While pulse oximetry has been found to be an acceptable method of hypoxemia detection, improving clinical decision making and efficient referral, many healthcare set ups in low- and middle-income countries have not been able to implement pulse oximetry into their practice.

MAIN BODY

A review of past pulse oximetry implementation attempts in low- and middle-income countries proposes the barriers and potential solutions for complete integration in the healthcare systems. The addition of pulse oximetry into WHO health guidelines would prove to improve detection of respiratory distress and ensuing therapeutic measures. Incorporation is limited by the cost and unavailability of pulse oximeters, and subsequent oxygen accessibility. This restriction is compounded by the lack of trained personnel, and healthcare provider misconceptions. These hurdles can be combated by focus on low-cost devices, and cooperation at national levels for development in healthcare infrastructure, resource transport, and oxygen delivery systems.

CONCLUSION

The implementation of pulse oximetry shows promise to improve child morbidity and mortality from pneumonia in low- and middle-income countries. Steady measures taken to improve access to pulse oximeters and oxygen supplies, along with enhanced medical provider training are encouraging steps to thorough pulse oximetry integration.

Modelling the cost-effectiveness of pulse oximetry in primary care management of acute respiratory infection in rural northern Thailand

OBJECTIVES

We aimed to determine the cost-effectiveness of supplementing standard care with pulse oximetry among children <5 years with acute respiratory infection (ARI) presenting to 32 primary care units in a rural district (total population 241,436) of Chiang Rai province, Thailand, and to assess the economic effects of extending pulse oximetry to older patients with ARI in this setting.

METHODS

We performed a model-based cost-effectiveness analysis from a health systems perspective. Decision trees were constructed for three patient categories (children <5 years, children 5-14 years, and adults), with a 1-year time horizon. Model parameters were based on data from 49,958 patients included in a review of acute infection management in the 32 primary care units, published studies, and procurement price lists. Parameters were varied in deterministic sensitivity analyses. Costs were expressed in 2021 US dollars with a willingness-to-pay threshold per DALY averted of $8624.

RESULTS

The annual direct cost of pulse oximetry, associated staff, training, and monitoring was $24,243. It reduced deaths from severe lower respiratory tract infections in children <5 years by 0.19 per 100,000 patients annually. In our population of 14,075 children <5 years, this was equivalent to 2.0 DALYs averted per year. When downstream costs such as those related to hospitalisation and inappropriate antibiotic prescription were considered, pulse oximetry dominated standard care, saving $12,757 annually. This intervention yielded smaller mortality gains in older patients but resulted in further cost savings, primarily by reducing inappropriate antibiotic prescriptions in these age groups. The dominance of the intervention was also demonstrated in all sensitivity analyses.

CONCLUSIONS

Pulse oximetry is a life-saving, cost-effective adjunct in ARI primary care management in rural northern Thailand. This finding is likely to be generalisable to neighbouring countries with similar disease epidemiology and health systems.

Evaluation of a New Smartphone Powered Low-cost Pulse Oximeter Device

Background

Measurement of blood oxygen saturation is a vital part of monitoring coronavirus 2019 (COVID-19) patients. Pulse oximetry is commonly used to measure blood oxygen saturation and pulse rate for appropriate clinical intervention. But the majority of direct-to-consumer grade pulse oximeters did not pass through in-vivo testing, which results in their accuracy being questionable. Besides this, the ongoing COVID-19 pandemic exposed the limitations of the device in resource limited areas since independent monitoring is needed for COVID-19 patients. The purpose of this study was to perform an in-vivo evaluation of a newly developed smartphone powered low-cost pulse oximeter.

Methods

The new prototype of a smartphone powered pulse oximeter was evaluated against the standard pulse oximeter by taking measurements from fifteen healthy volunteers. The accuracy of measurement was evaluated by calculating the percentage error and standard deviation. A repeatability and reproducibility test were carried out using the ANOVA method.

Results

The average accuracy for measuring spot oxygen saturation (SPO2) and pulse rate (PR) was 99.18% with a standard deviation of 0.57 and 98.78% with a standard deviation of 0.61, respectively, when compared with the standard pulse oximeter device. The repeatability and reproducibility of SPO2 measurements were 0.28 and 0.86, respectively, which is in the acceptable range.

Conclusion

The new prototype of smartphone powered pulse oximeter demonstrated better performance compared to the existing low-cost fingertip pulse oximeters. The device could be used for independent monitoring of COVID-19 patients at health institutions and also for home care.

A Comprehensive Assessment of The Eight Vital Signs

The term “vital sign” has been assigned to various phenomena with the presumptive intent to emphasize their importance in health care resulting in the emergence of eight vital signs with multiple designations and overlapping terms. This review developed a case definition for vital signs and identified and described the fifth through eighth vital signs. PubMed/Medline, Google and biographical databases were searched using the individual Medical Subject Headings (MeSH) terms, vital sign and fifth, vital sign and sixth, vital sign and seventh, and vital sign eighth. The search was limited to human clinical studies written in English literature from 1957 up until November 30, 2021. Excluded were articles containing the term vital sign if used alone without the qualifier fifth, sixth, seventh, or eighth or about temperature, blood pressure, pulse, and respiratory rate. One hundred ninety-six articles (122 for the fifth vital sign, 71 for the sixth vital sign, two for the seventh vital sign, and one for the eighth vital sign) constituted the final dataset. The vital signs consisted of 35 terms, classified into 17 categories compromising 186 unique papers for each primary authored article with redundant numbered vital signs for glucose, weight, body mass index, and medication compliance. Eleven terms have been named the fifth vital sign, 25 the sixth vital sign, three the seventh, and one as the eighth vital sign. There are four time-honored vital signs based on the case definition, and they represent an objective bedside measurement obtained noninvasively that is essential for life. Based on this case definition, pulse oximetry qualifies as the fifth while end-tidal CO2 and cardiac output as the sixth. Thus, these terms have been misappropriated 31 times. Although important to emphasize in patient care, the remainder are not vital signs and should not be construed in this manner.

Development of Low-Cost and Portable Pulse Oximeter Device with Improved Accuracy and Accessibility

Purpose

Methods

Results

Conclusion

Prevalence of hypoxaemia in children with pneumonia in low-income and middle-income countries: a systematic review and meta-analysis

Background

Pneumonia accounts for around 15% of all deaths of children younger than 5 years globally. Most happen in resource-constrained settings and are potentially preventable. Hypoxaemia is one of the strongest predictors of these deaths. We present an updated estimate of hypoxaemia prevalence among children with pneumonia in low-income and middle-income countries.

Methods

We conducted a systematic review using the following key concepts “children under five years of age” AND “pneumonia” AND “hypoxaemia” AND “low- and middle-income countries” by searching in 11 bibliographic databases and citation indices. We included all articles published between Nov 1, 2008, and Oct 8, 2021, based on observational studies and control arms of randomised and non-randomised controlled trials. We excluded protocol papers, articles reporting hypoxaemia prevalence based on less than 100 pneumonia cases, and articles published before 2008 from the review. Quality appraisal was done with the Joanna Briggs Institute tools. We reported pooled prevalence of hypoxaemia (SpO₂ <90%) by classification of clinical severity and by clinical settings by use of the random-effects meta-analysis models. We combined our estimate of the pooled prevalence of pneumonia with a previously published estimate of the number of children admitted to hospital due to pneumonia annually to calculate the total annual number of children admitted to hospital with hypoxaemic pneumonia.

Findings

We identified 2825 unique records from the databases, of which 57 studies met the eligibility criteria: 26 from Africa, 23 from Asia, five from South America, and four from multiple continents. The prevalence of hypoxaemia was 31% (95% CI 26–36; 101 775 children) among all children with WHO-classified pneumonia, 41% (33–49; 30 483 children) among those with very severe or severe pneumonia, and 8% (3–16; 2395 children) among those with non-severe pneumonia. The prevalence was much higher in studies conducted in emergency and inpatient settings than in studies conducted in outpatient settings. In 2019, we estimated that over 7 million children (95% CI 5–8 million) were admitted to hospital with hypoxaemic pneumonia. The studies included in this systematic review had high τ² (ie, 0·17), indicating a high level of heterogeneity between studies, and a high I² value (ie, 99·6%), indicating that the heterogeneity was not due to chance. This study is registered with PROSPERO, CRD42019126207.

Interpretation

The high prevalence of hypoxaemia among children with severe pneumonia, particularly among children who have been admitted to hospital, emphasises the importance of overall oxygen security within the health systems of low-income and middle-income countries, particularly in the context of the COVID-19 pandemic. Even among children with non-severe pneumonia that is managed in outpatient and community settings, the high prevalence emphasises the importance of rapid identification of hypoxaemia at the first point of contact and referral for appropriate oxygen therapy.

Funding

UK National Institute for Health Research (Global Health Research Unit on Respiratory Health [RESPIRE]; 16/136/109).

Prehospital Pediatric Respiratory Distress and Airway Management Training and Education: An NAEMSP Position Statement and Resource Document

Although pediatric airway and respiratory emergencies represent high-acuity situations, the ability of EMS clinicians to effectively manage these patients is hampered by infrequent clinical exposure and shortcomings in pediatric-specific education. Cognitive gaps in EMS clinicians' understanding of the differences between pediatric and adult airway anatomy and respiratory physiology and pathology, variability in the training provided to EMS clinicians, and decay of the psychomotor skills necessary to safely and effectively manage pediatric patients experiencing respiratory emergencies collectively pose significant threats to the quality and safety of care delivered to pediatric patients. NAEMSP recommends:Pediatric airway education should include discussion of the factors that make pediatric airway management challenging.EMS agencies should provide pediatric-specific education that addresses recognition and treatment of pediatric respiratory distress based upon pathophysiology affecting upper airways, lower airways, cardiovascular systems, or extrinsic causes of disordered breathing. Pediatric airway training should also differentiate between hypoxic and hypercapnic respiratory failure. Education should emphasize that the cognitive and psychomotor skills requisite in management of pediatric respiratory emergencies will differ across patient age groups.EMS clinicians should be provided education and training in technology-dependent children and children and youth with special health care needs.EMS clinicians should receive initial and ongoing education and training in pediatric airway and respiratory conditions that emphasizes the principle of using the least invasive most effective strategies to achieve oxygenation and ventilation.Initial and continuing pediatric-focused education should be structured to maintain EMS clinician competency in the assessment and management of pediatric airway and respiratory emergencies and should be provided on a recurring basis to mitigate the decay of EMS clinicians' knowledge and skills that occurs due to infrequent field-based clinical exposure.Integration of clinician education programs with quality management programs is essential for the development and delivery of initial and continuing education intended to help EMS clinicians attain and maintain proficiency in pediatric airway and respiratory management.

Oxygen saturation targets in pediatric respiratory disease

BACKGROUND

The present study aimed to assess the appropriate oxygen saturation target in patients with pediatric respiratory diseases by lowering the oxygen saturation target from SpO₂ 94% to 90%. No previous study has explored appropriate oxygen saturation targets in respiratory diseases other than bronchiolitis.

METHODS

The present, prospective, single-arm intervention trial enrolled pediatric inpatients with bronchiolitis, bronchitis, pneumonia, and asthma. The oxygen saturation target was lowered from SpO₂ 94% to 90% after the patients' general condition improved. The patients continued to be observed for 12 h after achieving SpO₂ 94%. The duration from the first cut-off point (SpO₂ 90% for 12 h without oxygen) to the second cut-off point (SpO₂ 94% for 12 h) was then evaluated.

RESULTS

In total, 248 patients completed the study. Patients with bronchiolitis, bronchitis, pneumonia, and asthma had an interval between the two cut-off points of 23.9, 15.5, 19.1, and 13.8 h, respectively, (mean 17.2 h; 95% confidence interval 15.0-19.5).

CONCLUSIONS

In generally healthy children, setting the oxygen saturation target at SpO₂ 90% after confirming improvement in their general condition was safe. The time required for increasing SpO₂ from 90% to 94% was longest in the patients with bronchiolitis.

Improving Capnography Use for Critically Ill Emergency Patients: An Implementation Study

OBJECTIVES

Capnography has established benefit during intubation and cardiopulmonary resuscitation (CPR). Implementation within emergency departments (EDs) has lagged. We sought to address barriers to improve documented capnography use for patients requiring intubation or CPR.

METHODS

A controlled before- and after-implementation study was performed in 2 urban EDs. The control site had an existing policy for capnography use. Interventions for the experimental site included a 5-minute informational video, placement of capnography monitors with a shortened warm-up period in all resuscitation rooms, laminated reminder cards, and feedback during staff meetings. Staff members were surveyed about knowledge before and after the intervention. Records were reviewed for documented capnography use for 3 months before and 6 months after the intervention. Change in documented use at the experimental site was compared with the control site.

RESULTS

At the experimental site, 118 providers participated and 190 records were reviewed; 544 records were reviewed from the control site. There was a significant increase in the proportion of documented capnography use at the experimental site (8% versus 19%, P = 0.04) compared with the control site (64% versus 71%, P = 0.10). However, there was no significant trend over time at the experimental site after the intervention (P = 0.86). Despite high baseline knowledge about capnography, providers had improvements in survey responses regarding indications for intubation and CPR, normal values, and minimum effective values during CPR.

CONCLUSIONS

Documented capnography use increased with simple interventions but with no positive trend. Additional work is needed to improve use, including further evaluation of capnography's implementation in the ED.

The impact of pulse oximetry on diagnosis, management and outcomes of acute febrile illness in low-income and middle-income countries: a systematic review

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.

A Cost Analysis of Pulse Oximetry as a Determinant in the Decision to Admit Infants With Mild to Moderate Bronchiolitis

OBJECTIVES

A previous randomized controlled trial showed that artificially elevating the pulse oximetry display resulted in fewer hospitalizations with no worse outcomes. This suggests that management decisions based mainly on pulse oximetry may unnecessarily increase health care costs. This study assessed the incremental cost of altered relative to true oximetry in infants with mild to moderate bronchiolitis.

METHODS

A cost analysis was undertaken from the health care system and societal perspectives using patient-level data from the randomized controlled trial, with a 5-day time horizon after emergency department visit. Infants aged 4 weeks to 12 months with mild to moderate bronchiolitis were randomized to pulse oximetry measurements with true or altered saturation values displayed by artificially increasing saturation 3% points above true values. Direct and indirect health care costs were measured. Sensitivity analyses were performed to assess parameter uncertainty.

RESULTS

From the health care system perspective, the average cost per patient was Can $1155 for altered oximetry and $1967 for true oximetry, with a net savings of $812. From a societal perspective, the average cost per patient was $1559 for altered oximetry and $2473 for true oximetry, with a net savings of $914. Probabilistic analyses demonstrated that altered oximetry remained the less costly study group, with an average savings of $810 (95% confidence interval, $748-$872) from the health care system perspective and $910 (95% confidence interval, $848-$973) from the societal system perspective.

CONCLUSIONS

Reliance on oximetry as a major determinant in the decision to hospitalize infants with mild to moderate bronchiolitis is associated with significantly greater costs.

Intermittent vs Continuous Pulse Oximetry in Hospitalized Infants With Stabilized Bronchiolitis: A Randomized Clinical Trial

IMPORTANCE

There is low level of evidence and substantial practice variation regarding the use of intermittent or continuous monitoring in infants hospitalized with bronchiolitis.

OBJECTIVE

To compare the effect of intermittent vs continuous pulse oximetry on clinical outcomes.

DESIGN, SETTING, AND PARTICIPANTS

This multicenter, pragmatic randomized clinical trial included infants 4 weeks to 24 months of age who were hospitalized with bronchiolitis from November 1, 2016, to May 31, 2019, with or without supplemental oxygen after stabilization at community and children's hospitals in Ontario, Canada.

INTERVENTIONS

Intermittent (every 4 hours, n = 114) or continuous (n = 115) pulse oximetry, using an oxygen saturation target of 90% or higher.

MAIN OUTCOMES AND MEASURES

The primary outcome was length of hospital stay from randomization to discharge. Secondary outcomes included length of stay from inpatient unit admission to discharge and outcomes measured from randomization: medical interventions, safety (intensive care unit transfer and revisits), parent anxiety and workdays missed, and nursing satisfaction.

RESULTS

Among 229 infants enrolled (median [IQR] age, 4.0 [2.2-8.5] months; 136 [59.4%] male; 101 [44.1%] from community hospital sites), the median length of hospital stay from randomization to discharge was 27.6 hours (interquartile range [IQR], 18.8-49.6 hours) in the intermittent group and 25.4 hours (IQR, 18.3-47.6 hours) in the continuous group (difference of medians, 2.2 hours; 95% CI, -1.9 to 6.3 hours; P = .17). No significant differences were observed between the intermittent and continuous groups in the median length of stay from inpatient unit admission to discharge: 49.1 (IQR, 37.2-87.0) hours vs 46.0 (IQR, 32.5-73.8) hours (P = .13) or in frequencies or durations of hospital interventions, such as oxygen supplementation initiation: 4 of 114 (3.5%) vs. 9 of 115 (7.8%) (P = .16) and median duration of oxygen supplementation: 20.6 (IQR, 7.6-46.1) hours vs. 21.4 (11.6-52.9) hours (P = .66). Similarly, there were no significant differences in frequencies of intensive care unit transfer: 1 of 114 (0.9%) vs 2 of 115 (2.7%) (P = .76); readmission to hospital: 3 of 114 (2.6%) in the intermittent group vs 4 of 115 (3.5%) in the continuous group (P > .99); parent anxiety: mean (SD) parent anxiety score, 2.9 (0.9) in the intermittent group vs 2.8 (0.9) in the continuous group (P = .40); or parent workdays missed: median workdays missed, 1.5 (IQR, 0.5-3.0) vs 1.5 (IQR, 0.5-2.5) (P = .36). Mean (SD) nursing satisfaction with monitoring was significantly greater in the intermittent group: 8.6 (1.7) vs 7.1 (2.8) of 10 workdays; the mean difference was 1.5 (95% CI, 0.9-2.2; P < .001).

CONCLUSIONS AND RELEVANCE

In this randomized clinical trial, among infants hospitalized with stabilized bronchiolitis with and without hypoxia and managed using an oxygen saturation target of 90% or higher, clinical outcomes, including length of hospital stay and safety, were similar with intermittent vs continuous pulse oximetry. Nursing satisfaction was greater with intermittent monitoring. Given that other important clinical practice considerations favor less intense monitoring, these findings support the standard use of intermittent pulse oximetry in stable infants hospitalized with bronchiolitis.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02947204.

Normal Percentiles for Respiratory Rate in Children-Reference Ranges Determined from an Optical Sensor

(1) Background: Increased respiratory rates (RRs) are described in several medical conditions, including pneumonia, bronchiolitis and asthma. There is variable methodology on how centiles for RR are derived in healthy children. Available age percentiles for RR have been generated using methods that have the potential themselves to alter the rate. (2) Methods: An optical respiratory sensor was used to measure RR. This technique enabled recording in awake children without the artefact of the observer's presence on the subject's RR. A cross-sectional sample of healthy children was obtained from maternity wards, childcare centres and schools in Brisbane, Queensland, Australia. (3) Results: RRs were observed in 560 awake and 103 sleeping children of which data from 320 awake and 94 sleeping children were used to develop centile charts for children from birth to 13 years of age. RR is higher when children are awake compared to asleep. There were significant differences between awake and sleeping RR in young children. The awake median RR was 59.3 at birth and 25.4 at 3 years of age. In comparison, the median sleeping RR was 41.4 at birth and 22.0 at 3 years. (4) Conclusions: The centile charts will assist in determining abnormal RRs in children and will contribute to further systematic reviews related to this important vital sign. This is particularly in relation to the data on children aged from 0 to 3 years, where data are presented on both the awake and sleeping state. Many studies in the literature fail to acknowledge the impact of sleep state in young children on RR.

Teaching the physical examination by context and by integrating hand-held ultrasound devices

Although practiced to this day, teaching the 'head-to-toe' physical examination (PE) does not appear to fully achieve its objective, and since the 1970s, there have been proposals to replace the traditional teaching of the head-to-toe examination by a selective PE aimed at testing diagnostic hypotheses; by a core PE to be supplemented by additional maneuvers as clinically indicated; and by limiting the number of PE maneuvers to be taught. The need to update the teaching of the PE is further indicated by the availability of hand-held pulse oximeters, spirometry and especially point of care ultrasound devices (PoCUS). This paper is a call to update the introduction of medical students into the PE by (a) teaching the PE by clinical contexts, rather than by organ systems, (b) restricting the number of PE maneuvers by discerning between a core of 'essential' PE signs of urgent conditions, 'important' signs that should supplement the core as clinically indicated, and 'optional' PE signs that are no longer useful, and (c) combining previously proposed alternatives of the traditional head-to-toe PE with application of hand-held ultrasound devices. We provide examples of essential, important and optional signs of the cardiovascular system.

Effect of rewarming in oxygenation and respiratory condition after neonatal exposure to moderate therapeutic hypothermia

BACKGROUND

To assess changes in clinical condition and oxygenation in neonates after rewarming following moderate therapeutic hypothermia (MTH) for neonatal encephalopathy.

METHODS

Retrospective study of 28 neonates receiving MTH in a tertiary neonatal intensive care unit in Israel. We compared pre-and 24 h post-rewarming arterial oxygen saturation (SaO₂) as measured by the blood gases analyzer, pulse-oximetry saturation (SpO₂), and cardio-respiratory condition.

RESULTS

The SpO₂ declined from 96.9% (±2.9) before rewarming to 95.2% (±2.6) after rewarming (p < 0.001). Twelve neonates (42.9%) had clinical respiratory impairment (needing higher respiratory support or had new onset desaturations). In 16 neonates (57.1%) with no change in respiratory support after rewarming, SpO₂ decreased from 98.3 ± 1.9% to 95.6 ± 3.0% (p < 0.001) and SaO₂ decreased from 97.1 ± 1.7% to 96.0 ± 2.3% (p = 0.002). The mean SpO₂ decrease was greater than mean SaO₂ decrease (2.63 ± 1.8 and 1.1 ± 1.3 respectively, p = 0.021).

CONCLUSION

Neonates who underwent MTH showed reduction in oxygenation after rewarming either by decreasing SpO₂ or increasing FiO₂ requirements. The SpO₂ decline was larger than the SaO₂ decline. We suggest careful monitoring of neonates after rewarming.

Use of Venous Pco2 in Determination of Death by Neurological Criteria in Children

BACKGROUND

Compare the increase in partial pressure of carbon dioxide (Pco₂) from venous blood samples with that of arterial blood samples during apnea challenge test in determination of death by neurological criteria.

METHODS

Prospective nonrandomized cohort study in tertiary care pediatric intensive care unit. Patients older than 37 week's gestation admitted to PICU with irreversible brain injury at the time when attending physician will perform apnea challenge test as part of brain death examination from October 2015 till September 2017.

INTERVENTIONS

None.

RESULTS

The primary outcome was to measure and compare the increase in Pco₂ from venous blood samples with that from arterial blood samples during apnea challenge test. A total of nine apnea challenge tests from seven patients (ages five months to 17 years) were included in the study. Pco₂ in venous blood sample increased less than that in arterial blood samples (venous, 26.1 mm Hg; S.D., 10.1; 95% confidence interval, 18 to 34 mm Hg; arterial, 33.9 mm Hg; S.D., 12.0; 95% confidence interval, 24 to 43 mm Hg) (P = 0.02).

CONCLUSION

Postapnea challenge test Pco₂ of 60 mm Hg along with increase of 20 mm Hg in venous blood sample correlated to Pco₂ greater than 60 mm Hg along with increase of greater than 20 mm Hg in arterial blood sample. Further studies are warranted to assess if current recommendations for determination of death by neurological criteria in children can be modified to allow for use of venous blood samples as an alternate to arterial blood samples.

Quantitative real-time pulse oximetry with ultrafast frequency-domain diffuse optics and deep neural network processing

Pulse oximetry is a ubiquitous optical technology, widely used for diagnosis and treatment guidance. Current pulse oximeters provide indications of arterial oxygen saturation. We present here a new quantitative methodology that extends the capability of pulse oximetry and provides real-time molar concentrations of oxy- and deoxy-hemoglobin at rates of up to 27 Hz by using advanced digital hardware, real-time firmware processing, and ultra-fast optical property calculations with a deep neural network (DNN). The technique utilizes a high-speed frequency domain spectroscopy system with five frequency-multiplexed wavelengths. High-speed demultiplexing and data reduction were performed in firmware. The DNN inversion algorithm was benchmarked as five orders of magnitude faster than conventional iterative methods for optical property extractions. The DNN provided unbiased optical property extractions, with an average error of 0 ± 5.6% in absorption and 0 ± 1.4% in reduced scattering. Together, these improvements enabled the measurement, calculation, and real-time continuous display of hemoglobin concentrations. A proof-of-concept cuff occlusion measurement was performed to demonstrate the ability of the device to track oxy- and deoxy-hemoglobin, and measure quantitative photoplethysmographic changes during the cardiac cycle. This technique substantially extends the capability of pulse oximetry and provides unprecedented real-time non-invasive functional information with broad applicability for cardiopulmonary applications.

Minimizing Medical Radiation Exposure by Incorporating a New Radiation "Vital Sign" into the Electronic Medical Record: Quality of Care and Patient Safety

There is a clearly perceived and imminent need to decrease unnecessary and detrimental exposure to medical ionizing radiation. We propose a new radiation "vital sign" that incorporates cumulative radiation exposure to create a risk score on the basis of an individualized assessment of potential harm from additional exposure to medical radiation. We propose to then tie the risk score to real-time, evidence-based, clinical decision support for procedures that use ionizing radiation. Additionally, we offer recommendations that minimize unnecessary or low-yield uses. Preference is given to approaches and modalities that use less or no ionizing radiation and that are medically appropriate, acceptable to, and safer for patients.

Barriers to the Implementation of Newborn Pulse Oximetry Screening: A Different Perspective

Pulse oximetry screening of the well newborn to assist in the diagnosis of critical congenital heart disease (CCHD) is increasingly being adopted. There are advantages to diagnosing CCHD prior to collapse, particularly if this occurs outside of the hospital setting. The current recommended approach links pulse oximetry screening with the assessment for CCHD. An alternative approach is to document the oxygen saturation as part of a routine set of vital signs in each newborn infant prior to discharge, delinking the measurement of oxygen saturation from assessment for CCHD. This approach, the way that many hospitals which contribute to the Australian New Zealand Neonatal Network (ANZNN) have introduced screening, has the potential benefits of decreasing parental anxiety and expectation, not requiring specific consent, changing the interpretation of false positives and therefore the timing of the test, and removing the pressure to perform an immediate echocardiogram if the test is positive. There are advantages of introducing a formal screening program, including the attainment of adequate funding and a universal approach, but the barriers noted above need to be dealt with and the process of acceptance by a national body as a screening test can take many years.

The influence of reducing fever on blood oxygen saturation in children

Laboratory-based studies on the oxyhemoglobin dissociation curve (ODC) suggest that high blood temperature decreases the affinity of hemoglobin for oxygen. The aim of the study was to evaluate the influence of pyrexia on oxygen saturation (SpO₂) in children presenting to the emergency department. Normoxemic children with body temperature at or above 38.5 °C were included. Patients with a dynamic respiratory disease were excluded. SpO₂ was measured before and after antipyretic treatment. The changes in body temperature and SpO₂ were assessed and compared to the changes predicted from the ODC. Thirty-four children completed the study. Mean temperature at presentation was 39.17 ± 0.549 °C and mean SpO₂ was 96.15 ± 2.21%. The mean decrease in temperature after antipyretic treatment was 1.71 ± 0.67 °C and mean increase in SpO₂ was 0.95 ± 1.76%. Among children in whom pyrexia decreased by 1.5 °C or more, the mean increase in SpO₂ was 1.45 ± 1.57%. The measured increase in SpO₂ was close to the increase anticipated from the ODC.

CONCLUSION

Pyrexia was associated with decreased SpO₂ in normoxemic children. The influence of pyrexia in children with low-normal oxygen saturation is expected to be much higher because of the non-linear shape of the ODC. Physicians treating patients with fever should be aware of this effect, especially in patients with borderline hypoxia. What is Known: • High blood temperature decreases the affinity of oxygen to hemoglobin. • It is not known whether fever would decrease SpO ₂ . What is New: • Fever is associated with decreased SpO ₂ .

Initial Asthma Severity Assessment Tools as Predictors of Hospitalization

BACKGROUND

Assessment tools to classify and prioritize patients, such as systems of triage, and indicators of severity, such as clinical respiratory scores, are helpful in guiding the flow of asthmatic patients in the emergency department.

OBJECTIVE

Our aim was to assess the performance of the Pediatric Assessment Triangle (PAT), triage level (TL), Pulmonary Score (PS), and initial O₂ saturation (O₂ sat), in predicting hospitalization in pediatric acute asthma exacerbations.

STUDY DESIGN

Retrospective study evaluating PAT, TL, and PS at presentation, and initial O₂ sat of asthmatic children in the pediatric emergency department (PED). The primary outcome measure was the rate of hospitalization. Secondary outcomes were length of stay (LOS) in the PED and admission to the pediatric intensive care unit (PICU).

RESULTS

PAT, TL, PS, and initial O₂ sat were recorded in 14,953 asthmatic children. Multivariate analysis yielded the following results: Abnormal PAT and more severe TLs (I-II) were independent risk factors for hospitalization (odds ratio [OR] 1.6, 95% confidence interval [CI] 1.4-1.8; OR 3.4, 95% CI 2.6-4.3, respectively) and longer LOS (OR 1.5, 95% CI 1.3-1.7; OR 2.6, 95% CI 2-3.3, respectively). PS > 3 showed a strong association with hospitalization (OR 8.1, 95% CI 7-9.4), PICU admission (OR 9.6, 95% CI 3-30.9) and longer LOS (OR 6.2, 95% CI 5.6-6.9). O₂ sat < 94% was an independent predictor of admission (OR 5.2, 95% CI 4.6-5.9), PICU admission (OR 4.6, 95% CI 4.5-4.6), and longer LOS (OR 4.6, 95% CI 4.1-5.2).

CONCLUSIONS

PAT, TL, PS, and initial O₂ sat are good predictors of hospitalization in pediatric acute asthma exacerbations.

Continuous noninvasive monitoring in the neonatal ICU

PURPOSE OF REVIEW

Standard hemodynamic monitoring such as heart rate and systemic blood pressure may only provide a crude estimation of organ perfusion during neonatal intensive care. Pulse oximetry monitoring allows for continuous noninvasive monitoring of hemoglobin oxygenation and thus provides estimation of end-organ oxygenation. This review aims to provide an overview of pulse oximetry and discuss its current and potential clinical use during neonatal intensive care.

RECENT FINDINGS

Technological advances in continuous assessment of dynamic changes in systemic oxygenation with pulse oximetry during transition to extrauterine life and beyond provide additional details about physiological interactions among the key hemodynamic factors regulating systemic blood flow distribution along with the subtle changes that are frequently transient and undetectable with standard monitoring.

SUMMARY

Noninvasive real-time continuous systemic oxygen monitoring has the potential to serve as biomarkers for early-organ dysfunction, to predict adverse short-term and long-term outcomes in critically ill neonates, and to optimize outcomes. Further studies are needed to establish values predicting adverse outcomes and to validate targeted interventions to normalize abnormal values to improve outcomes.

Does pulse oximeter use impact health outcomes? A systematic review

OBJECTIVE

Do newborns, children and adolescents up to 19 years have lower mortality rates, lower morbidity and shorter length of stay in health facilities where pulse oximeters are used to inform diagnosis and treatment (excluding surgical care) compared with health facilities where pulse oximeters are not used?

DESIGN

Studies were obtained for this systematic literature review by systematically searching the Database of Abstracts of Reviews of Effects, Cochrane, Medion, PubMed, Web of Science, Embase, Global Health, CINAHL, WHO Global Health Library, international health organisation and NGO websites, and study references.

PATIENTS

Children 0-19 years presenting for the first time to hospitals, emergency departments or primary care facilities.

INTERVENTIONS

Included studies compared outcomes where pulse oximeters were used for diagnosis and/or management, with outcomes where pulse oximeters were not used.

MAIN OUTCOME MEASURES

mortality, morbidity, length of stay, and treatment and management changes.

RESULTS

The evidence is low quality and hypoxaemia definitions varied across studies, but the evidence suggests pulse oximeter use with children can reduce mortality rates (when combined with improved oxygen administration) and length of emergency department stay, increase admission of children with previously unrecognised hypoxaemia, and change physicians' decisions on illness severity, diagnosis and treatment. Pulse oximeter use generally increased resource utilisation.

CONCLUSIONS

As international organisations are investing in programmes to increase pulse oximeter use in low-income settings, more research is needed on the optimal use of pulse oximeters (eg, appropriate oxygen saturation thresholds), and how pulse oximeter use affects referral and admission rates, length of stay, resource utilisation and health outcomes.

Monitoring the respiratory rate by miniature motion sensors in premature infants: a comparative study

OBJECTIVE

Existing respiratory rate (RR) monitors suffer from inaccuracy. The study assesses the accuracy of a novel modality that monitors lung ventilation with miniature motion sensors.

STUDY DESIGN

RR was measured by three methods: impedance technology, motion sensors and visual count, in babies (n=9) that breathed spontaneously or with respiratory support and babies (n=12) that received high-frequency oscillatory ventilation (HFOV).

RESULTS

A line close to equality (slope=0.96, r(2)=0.83) was obtained between the motion sensor and the visual count of the RR with narrow 95% limits of agreements (<14.0 b.p.m.). The relationship between the impedance and the visual count showed a lower correlation (r(2)=0.65) and wider 95% limits of agreements (21.4 b.p.m.). The motion sensor- and the ventilator-determined RRs demonstrated a good agreement during HFOV, whereas the impedance failed to measure the RR during HFOV.

CONCLUSION

Monitoring RR with motion sensors is more accurate compared with the impedance, in infants, in all ventilation modes.

Evidence-Based Protocols to Guide Pulse Oximetry and Oxygen Weaning in Inpatient Children with Asthma and Bronchiolitis: A Pilot Project

Nurses', respiratory therapists' (RTs), and physicians' concerns about oxygen weaning practices and pulse oximetry use in healthy children during inpatient admissions prompted this multidisciplinary evidence-based project. A nurse-led inter-professional team found lack of consistent oxygen weaning practices and lack of guidelines for nurses or RTs regarding pulse oximetry use with children admitted for acute respiratory illness. The team created and piloted evidence-based oxygen weaning and pulse oximetry protocols. After a 6 month pilot, children in the pilot had shorter length of stay, time on oxygen, and time on continuous pulse oximetry. Protocols improved patient outcomes and decreased associated charges.

Utility and feasibility of integrating pulse oximetry into the routine assessment of young infants at primary care clinics in Karachi, Pakistan: a cross-sectional study

Background

Hypoxemia may occur in young infants with severe acute illnesses or congenital cardiac anomalies, but is not reliably detected on physical exam. Pulse oximetry (PO) can be used to detect hypoxemia, but its application in low-income countries has been limited, and its feasibility in the routine assessment of young infants (aged 0–59 days) has not been previously studied. The aim of this study was to characterize the operational feasibility and parent/guardian acceptability of incorporating PO into the routine clinical assessment of young infants in a primary care setting in a low-income country.

Methods

This was a cross-sectional study of 862 visits by 529 infants at two primary care clinics in Karachi, Pakistan (March to June, 2013). After clinical assessment, oxygen saturation (Sp02) was measured by a handheld PO device (Rad-5v, Masimo Corporation) according to a standardized protocol. Performance time (PT) was the time between sensor placement and attainment of an acceptable PO reading (i.e., stable SpO₂ + 1 % for at least 10 s, heart rate displayed, and adequate signal indicators). PT included the time for one repeat attempt at a different anatomical site if the first attempt did not yield an acceptable reading within 1 min. Parent/guardian acceptability of PO was based on a questionnaire and unprompted comments about the procedure. All infants underwent physician assessment.

Results

Acceptable PO readings were obtained in ≤1 and ≤5 min at 94.4 % and 99.8 % of visits, respectively (n = 862). Median PT was 42 s (interquartile range 37; 50). Parents/guardians overwhelmingly accepted PO (99.6 % overall satisfaction, n = 528 first visits). Of 10 infants with at least one visit with Sp02 <92 % on a first PO attempt, 3 did not have a significant acute illness on physician assessment. There were no PO-related adverse events.

Discussion

Using a commercially available handheld pulse oximeter, acceptable Sp02 measurements were obtained in nearly all infants in under 1 minute. The procedure was readily integrated into existing assessment pathways and parents/guardians had positive views of the technology.

Conclusions

When incorporated into routine clinical assessment of young infants at primary care clinics in a low-income country, PO was feasible and acceptable to parents/guardians. Future research is needed to determine if the introduction of routine PO screening of young infants will improve outcomes in low-resource settings.

Lost without trace: oximetry signal dropout in preterm infants

Oxygen saturation (SpO2) signal dropout leaves caregivers without a reliable measure to guide oxygen therapy. We studied SpO2 dropout in preterm infants on continuous positive airway pressure, noting the SpO2 values at signal loss and recovery and thus the resultant change in SpO2, and the factors influencing this parameter. In 32 infants of median gestation 26 weeks, a total of 3932 SpO2 dropout episodes were identified (1.1 episodes/h). In the episodes overall, SpO2 decreased by 1.1%, with the SpO2 change influenced by starting SpO2 (negative correlation), but not dropout duration. For episodes starting in hypoxia (SpO2 <85%), SpO2 recovered at a median of 3.2% higher than at SpO2 dropout, with a downward trajectory in a quarter of cases. We conclude that after signal dropout SpO2 generally recovers in a relative normoxic range. Blind FiO2 adjustments are thus unlikely to be of benefit during most SpO2 dropout episodes.

Predictors of duration and treatment failure of severe pneumonia in hospitalized young Nepalese children

Background

Pneumonia in young children is still the most frequent cause of death in developing countries. We aimed to identify predictors for recovery and treatment failure in children hospitalized with severe pneumonia.

Methods

We enrolled 610 Nepalese children, aged 2 – 35 months from February 2006 to June 2008. Study participants were provided with standard treatment for pneumonia and followed up until discharge. Three multiple regression models representing clinical variables, clinical and radiological combined and all variables, including C-reactive protein (CRP) and viral etiology were used to assess the associations.

Results

The median age of study participants was 6 months with 493 (82%) infants and 367 (61%) males. The median time (IQR) till recovery was 49 (31, 87) hours and treatment failure was experienced by 209 (35%) of the children. Younger age, hypoxia on admission and radiographic pneumonia were independent predictors for both prolonged recovery and risk of treatment failure. While wasting and presence of any danger sign also predicted slower recovery, Parainfluenza type 1 isolated from the nasopharynx was associated with earlier resolution of illness. Gender, being breastfed, stunting, high fever, elevated CRP, presence of other viruses and supplementation with oral zinc did not show any significant association with these outcomes.

Conclusion

Age, hypoxia and consolidation on chest radiograph were significant predictors for time till recovery and treatment failure in children with severe pneumonia. While chest radiograph is not always needed, detection and treatment of hypoxia is a crucial step to guide the management of hospitalized children with pneumonia.

Moving beyond silos: How do we provide distributed personalized medicine to pregnant women everywhere at scale? Insights from PRE-EMPT

While we believe that pre-eclampsia matters-because it remains a leading cause of maternal and perinatal morbidity and mortality worldwide-we are convinced that the time has come to look beyond single clinical entities (e.g. pre-eclampsia, postpartum hemorrhage, obstetric sepsis) and to look for an integrated approach that will provide evidence-based personalized care to women wherever they encounter the health system. Accurate outcome prediction models are a powerful way to identify individuals at incrementally increased (and decreased) risks associated with a given condition. Integrating models with decision algorithms into mobile health (mHealth) applications could support community and first level facility healthcare providers to identify those women, fetuses, and newborns most at need of facility-based care, and to initiate lifesaving interventions in their communities prior to transportation. In our opinion, this offers the greatest opportunity to provide distributed individualized care at scale, and soon.

Reliability of pulse oximetry during cardiopulmonary resuscitation in a piglet model of neonatal cardiac arrest

BACKGROUND

Pulse oximetry is widely used in intensive care and emergency conditions to monitor arterial oxygenation and to guide oxygen therapy.

OBJECTIVE

To study the reliability of pulse oximetry in comparison with CO-oximetry in newborn piglets during cardiopulmonary resuscitation (CPR).

METHODOLOGY

In a prospective cohort study in 30 healthy newborn piglets, cardiac arrest was induced, and thereafter each piglet received CPR for 20 min. Arterial oxygen saturation was monitored continuously by pulse oximetry (SpO2). Arterial blood was analyzed for functional oxygenation (SaO2) every 2 min. SpO2 was compared with coinciding SaO2 values and bias considered whenever the difference (SpO2 - SaO2) was beyond ±5%.

RESULTS

Bias values were decreased at the baseline measurements (mean: 2.5 ± 4.6%) with higher precision and accuracy compared with values across the experiment. Two minutes after cardiac arrest, there was a marked decrease in precision and accuracy as well as an increase in bias up to 13 ± 34%, reaching a maximum of 45.6 ± 28.3% after 10 min over a mean SaO2 range of 29-58%.

CONCLUSION

Pulse oximetry showed increased bias and decreased accuracy and precision during CPR in a model of neonatal cardiac arrest. We recommend further studies to clarify the exact mechanisms of these false readings to improve reliability of pulse oximetry during the marked desaturation and hypoperfusion found during CPR.

Oxygen saturation index and severity of hypoxic respiratory failure

BACKGROUND

The oxygenation index (OI = mean airway pressure, MAP × FiO2 × 100 : PaO2) is used to assess the severity of hypoxic respiratory failure (HRF) and persistent pulmonary hypertension of the newborn (PPHN). An indwelling arterial line or arterial punctures are necessary to obtain PaO2 for the calculation of OI. Oxygenation can be continuously and noninvasively assessed using pulse oximetry. The use of the oxygen saturation index (OSI = MAP × FiO2 × 100 : SpO2) can be an alternate method of assessing the severity of HRF.

OBJECTIVE

To evaluate the correlation between OSI and OI in the following: (1) neonates with HRF and (2) a lamb model of meconium aspiration syndrome.

METHODS

Human neonates: a retrospective chart review of 74 ventilated late preterm/term neonates with indwelling arterial access and SpO2 values in the first 24 h of life was conducted. OSI and OI were calculated and correlated. Lamb model: arterial blood gases were drawn and preductal SpO2 was documented in 40 term newborn lambs with asphyxia and meconium aspiration. OI and OSI were calculated and correlated with pulmonary vascular resistance (PVR).

RESULTS

Mean values of OSI and OI showed a correlation coefficient of 0.952 in neonates (mean value of 308 observations in 74 neonates) and 0.948 in lambs (mean value of 743 observations in 40 lambs). In lambs, with increasing PVR, there was a decrease in OI and OSI.

CONCLUSION

OSI correlates significantly with OI in infants with HRF. This noninvasive measure may be used to assess the severity of HRF and PPHN in neonates without arterial access.

Pulse oximetry in very low birth weight infants

Pulse oximetry has become ubiquitous and is used routinely during neonatal care. Emerging evidence highlights the continued uncertainty regarding definition of the optimal range to target pulse oximetry oxygen saturation levels in very low birth weight infants. Furthermore, maintaining optimal oxygen saturation targets is a demanding and tedious task because of the frequency with which oxygenation changes, especially in these small infants receiving prolonged respiratory support. This article addresses the historical perspective, basic physiologic principles behind pulse oximetry operation, and the use of pulse oximetry in targeting different oxygen ranges at various time-points throughout the neonatal period.

Non invasive monitoring in mechanically ventilated pediatric patients

Cardiopulmonary monitoring is a key component in the evaluation and management of critically ill patients. Clinicians typically rely on a combination of invasive and non-invasive monitoring to assess cardiac output and adequacy of ventilation. Recent technological advances have led to the introduction: of continuous non-invasive monitors that allow for data to be obtained at the bedside of critically ill patients. These advances help to identify hemodynamic changes and allow for interventions before complications occur. In this manuscript, we highlight several important methods of non-invasive cardiopulmonary monitoring, including capnography, transcutaneous monitoring, pulse oximetry, and near infrared spectroscopy.

Clinical use of pulse oximetry: official guidelines from the Thoracic Society of Australia and New Zealand

Pulse oximetry provides a simple, non-invasive approximation of arterial oxygenation in a wide variety of clinical settings including emergency and critical-care medicine, hospital-based and ambulatory care, perioperative monitoring, inpatient and outpatient settings, and for specific diagnostic applications. Pulse oximetry is of utility in perinatal, paediatric, adult and geriatric populations but may require use of age-specific sensors in these groups. It plays a role in the monitoring and treatment of respiratory dysfunction by detecting hypoxaemia and is effective in guiding oxygen therapy in both adult and paediatric populations. Pulse oximetry does not provide information about the adequacy of ventilation or about precise arterial oxygenation, particularly when arterial oxygen levels are very high or very low. Arterial blood gas analysis is the gold standard in these settings. Pulse oximetry may be inaccurate as a marker of oxygenation in the presence of dyshaemoglobinaemias such as carbon monoxide poisoning or methaemoglobinaemia where arterial oxygen saturation values will be overestimated. Technical considerations such as sensor position, signal averaging time and data sampling rates may influence clinical interpretation of pulse oximetry readings.

High rate of missing vital signs data at triage in a paediatric emergency department

BACKGROUND

Vital signs measurement is considered standard practice in paediatric emergency department triage assessment, but studies have shown variable incidence of missing data.

OBJECTIVES

To evaluate the rate of missing data for vital signs at triage and to determine clinical and environmental predictive factors.

METHODS

A retrospective cohort design was used to study a database of consecutive patients registered at a tertiary paediatric emergency department during randomly chosen shifts. Demographic and clinical data were collected. Univariate and multivariate logistic regression analyses were performed to evaluate the determinants of missing data for body temperature, heart rate, respiratory rate, blood pressure and pulse oximetry.

RESULTS

There were 2081 patients triaged during the study periods. On multivariate logistic regression analysis, triage level (from 1 = priority to 4 = nonurgent) was an independent predictor of missing data for heart rate, respiratory rate, blood pressure and pulse oximetry (OR 1.48 to 2.05). Patients visiting the emergency department during the day shift (OR 1.08 to 4.72) and the evening shift (OR 1.38 to 9.24) had a higher rate of missing data than those visiting during the night shift. A decreased level of consciousness, an immunocompromised state and referral by a physician did not meet statistical significance as predictive factors.

CONCLUSIONS

There was a high rate of missing data for vital signs. Factors related to patients' clinical characteristics, such as acuity of triage level, were associated with a higher rate of vital signs documentation at triage. An environmental factor, shift of presentation, was also independently associated with a higher rate.

Acute respiratory failure in children

Acute respiratory failure is the most common medical emergency in children. One aim of this review is to discuss the physiologic peculiarities that explain the increased vulnerability of infants and children to any pathology affecting the respiratory tract. The other aim is to highlight the importance of history taking and correct physical examination for early recognition of an impending catastrophic progression of respiratory failure. Under most circumstances, correct physical examination alone allows one to pinpoint the cause to a particular part of the respiratory system and to make the appropriate decisions for a proactive and life-saving management of the critically ill child.

The role of pulse oximetry in chiropractic practice: a rationale for its use

OBJECTIVE

Pulse oximetry is used regularly to assess oxygen saturation levels. The objective of this commentary is to discuss a rationale for using pulse oximetry in chiropractic practice.

DISCUSSION

Pulse oximetry may offer doctors of chiropractic a way to monitor patients' oxygen saturation levels. Quantification of saturation values with heart rate may give clinical aid to the management of chiropractic patients. Markedly reduced saturation levels may necessitate medical referral, whereas mildly reduced levels could lead to changes in chiropractic management.

CONCLUSIONS

Pulse oximetry has the potential to be an integral part of chiropractic practice.

Relationship between oxygen saturation and umbilical cord pH immediately after birth

BACKGROUND

The aim of this study is to determine the relationship between oxygen saturation (SpO(2)) by pulse oximetry levels and umbilical cord arterial pH values in healthy newborns during the first 15 minutes of life.

METHODS

The study was performed with healthy term, appropriate-for-gestational-age newborn infants. The infants were divided in two groups: umbilical cord arterial blood pH value ≤7.19 (group 1) and >7.19 (group 2); SpO(2) levels during the first 15 minutes of life were compared between groups.

RESULTS

The study was completed with 129 infants (33 in group 1 and 96 in group 2). A significant correlation was found between first-measured preductal and postductal SpO(2) levels by pulse oximetry and umbilical cord arterial pH values ([r²:0.72(0.62 -0.79); p < 0.001] and [r²:0.32(0.25 - 0.54); p < 0.001], respectively). In group 1, infants had lower SpO(2) levels at both preductal and postductal measurements during the first 11 minutes of life and time to reach ≥90% SpO(2) level was longer compared with infants in group 2.

CONCLUSION

Determination of umbilical arterial blood pH values, in addition to clinical findings and oxygen saturation measurements, might be helpful in deciding the concentration of oxygen and whether or not to continue oxygen supplementation in the delivery room.