Pulse oximetry in paediatric primary care in low-income and middle-income countries

Designing a Smartphone-Based Pulse Oximeter for Children in South Africa (Phefumla Project): Qualitative Analysis of Human-Centered Design Workshops With Health Care Workers

Background

Pulse oximeters noninvasively measure blood oxygen levels, but these devices have rarely been designed for low-resource settings and are inconsistently available at outpatient clinics.

Objective

The Phefumla project aims to develop and validate a pediatric smartphone-based pulse oximeter designed specifically for this context. We present the process of human-centered oximeter design with health care workers in South Africa.

Methods

We purposively sampled 19 health care workers from 5 clinics in Khayelitsha, Cape Town. Using a human-centered design approach, we conducted participatory workshops with four activities with health care workers: (1) they received 3D-printed prototypes of potential oximeter designs to provide feedback; (2) we demonstrated on dolls how they would use the novel oximeter; (3) they used pile sorting to rank design features and suggest additional features they desired; and (4) they designed their preferred user interface using a whiteboard, marker, and magnetized features that could be repositioned. We audio recorded the workshops, photographed outputs, and took detailed field notes. Analysis involved iterative review of these data to describe preferences, identify key design updates, and provide modifications.

Results

Participants expressed a positive sentiment toward the idea of a smartphone pulse oximeter and suggested that a pediatric device would address an important gap in outpatient care. Specifically, participants expressed a preference for the prototype that they felt enabled more diversity in the way it could be used. There was a strong tendency to prioritize pragmatic design features, such as robustness, which was largely dictated by health care worker context. They also added features that would allow the oximeter device to serve other clinical functions in addition to oxygen saturation measurement, such as temperature and respiratory rate measurements.

Conclusions

Our end user-centered rapid participatory approach led to tangible design changes and prompted design discussions that the team had not previously considered. Overall, health care workers prioritized pragmatism for pediatric pulse oximeter device design.

Clinical hypoxemia score for outpatient child pneumonia care lacking pulse oximetry in Africa and South Asia

Background

Pulse oximeters are not routinely available in outpatient clinics in low- and middle-income countries. We derived clinical scores to identify hypoxemic child pneumonia.

Methods

This was a retrospective pooled analysis of two outpatient datasets of 3-35 month olds with World Health Organization (WHO)-defined pneumonia in Bangladesh and Malawi. We constructed, internally validated, and compared fit & discrimination of four models predicting SpO2 < 93% and <90%: (1) Integrated Management of Childhood Illness guidelines, (2) WHO-composite guidelines, (3) Independent variable least absolute shrinkage and selection operator (LASSO); (4) Composite variable LASSO.

Results

12,712 observations were included. The independent and composite LASSO models discriminated moderately (both C-statistic 0.77) between children with a SpO2 < 93% and ≥94%; model predictive capacities remained moderate after adjusting for potential overfitting (C-statistic 0.74 and 0.75). The IMCI and WHO-composite models had poorer discrimination (C-statistic 0.56 and 0.68) and identified 20.6% and 56.8% of SpO2 < 93% cases. The highest score stratum of the independent and composite LASSO models identified 46.7% and 49.0% of SpO2 < 93% cases. Both LASSO models had similar performance for a SpO2 < 90%.

Conclusions

In the absence of pulse oximeters, both LASSO models better identified outpatient hypoxemic pneumonia cases than the WHO guidelines. Score external validation and implementation are needed.

Risk and accuracy of outpatient-identified hypoxaemia for death among suspected child pneumonia cases in rural Bangladesh: a multifacility prospective cohort study

BACKGROUND

Hypoxaemic pneumonia mortality risk in low-income and middle-income countries is high in children who have been hospitalised, but unknown among outpatient children. We sought to establish the outpatient burden, mortality risk, and prognostic accuracy of death from hypoxaemia in children with suspected pneumonia in Bangladesh.

METHODS

We conducted a prospective community-based cohort study encompassing three upazila (subdistrict) health complex catchment areas in Sylhet, Bangladesh. Children aged 3-35 months participating in a community surveillance programme and presenting to one of three upazila health complex Integrated Management of Childhood Illness (IMCI) outpatient clinics with an acute illness and signs of difficult breathing (defined as suspected pneumonia) were enrolled in the study; because lower respiratory tract infection mortality mainly occurs in children younger than 1 year, the primary study population comprised children aged 3-11 months. Study physicians recorded WHO IMCI pneumonia guideline clinical signs and peripheral arterial oxyhaemoglobin saturations (SpO2) in room air. They treated children with pneumonia with antibiotics (oral amoxicillin [40 mg/kg per dose twice per day for 5-7 days, as per local practice]), and recommended oxygen, parenteral antibiotics, and hospitalisation for those with an SpO2 of less than 90%, WHO IMCI danger signs, or severe malnutrition. Community health workers documented the children's vital status and the date of any vital status changes during routine household surveillance (one visit to each household every 2 months). The primary outcome was death at 2 weeks after enrolment in children aged 3-11 months (primary study population) and 12-35 months (secondary study population). Primary analyses included estimating the outpatient prevalence, mortality risk, and prognostic accuracy of hypoxaemia for death in children aged 3-11 months with suspected pneumonia. Risk ratios were produced by fitting a multivariable model that regressed predefined SpO2 ranges (<90%, 90-93%, and 94-100%) on the primary 2-week mortality outcome (binary outcome) using Poisson models with robust variance estimation. We established the prognostic accuracy of WHO IMCI guidelines for death with and without varying SpO2 thresholds.

FINDINGS

Participants were recruited between Sept 1, 2015, to Aug 31, 2017. During the study period, a total of 7440 children aged 3-35 months with the first suspected pneumonia episode were enrolled, of whom 3848 (54·3%) with an attempted pulse oximeter measurement and 2-week outcome were included in our primary study population of children aged 3-11-months. Among children aged 3-11 months, an SpO2 of less than 90% occurred in 102 (2·7%) of 3848 children, an SpO2 of 90-93% occurred in 306 (8·0%) children, a failed SpO2 measurement occurred in 67 (1·7%) children, and 24 (0·6%) children with suspected pneumonia died. Compared with an SpO2 of 94-100% (3373 [87·7%] of 3848), the adjusted risk ratio for death was 10·3 (95% CI 3·2-32·3; p<0·001) for an SpO2 of less than 90%, 4·3 (1·5-11·8; p=0·005) for an SpO2 of 90-93%, and 11·4 (3·1-41·4; p<0·001) for a failed measurement. When not considering pulse oximetry, of the children who died, WHO IMCI guidelines identified only 25·0% (95% CI 9·7-46·7; six of 24 children) as eligible for referral to hospital. For identifying deaths, in children with an SpO2 of less than 90% WHO IMCI guidelines had a 41·7% sensitivity (95% CI 22·1-63·4) and 89·7% specificity (88·7-90·7); for children with an SpO2 of less than 90% or measurement failure the guidelines had a 54·2% sensitivity (32·8-74·4) and 88·3% specificity (87·2-89·3); and for children with an SpO2 of less than 94% or measurement failure the guidelines had a 62·5% sensitivity (40·6-81·2) and 81·3% specificity (80·0-82·5).

INTERPRETATION

These findings support pulse oximeter use during the outpatient care of young children with suspected pneumonia in Bangladesh as well as the re-evaluation of the WHO IMCI currently recommended threshold of an SpO2 less than 90% for hospital referral.

FUNDING

Fogarty International Center of the National Institutes of Health (K01TW009988), The Bill & Melinda Gates Foundation (OPP1084286 and OPP1117483), and GlaxoSmithKline (90063241).

Defining the role of host biomarkers in the diagnosis and prognosis of the severity of childhood pneumonia: a prospective cohort study

Reliable tools to inform outpatient management of childhood pneumonia in resource-limited settings are needed. We investigated the value added by biomarkers of the host infection response to the performance of the Liverpool quick Sequential Organ Failure Assessment score (LqSOFA), for triage of children presenting with pneumonia to a primary care clinic in a refugee camp on the Thailand-Myanmar border. 900 consecutive presentations of children aged ≤ 24 months meeting WHO pneumonia criteria were included. The primary outcome was receipt of supplemental oxygen. We compared discrimination of a clinical risk score (LqSOFA) to markers of endothelial injury (Ang-1, Ang-2, sFlt-1), immune activation (CHI3L1, IP-10, IL-1ra, IL-6, IL-8, IL-10, sTNFR-1, sTREM-1), and inflammation (CRP, PCT), and quantified the net benefit of including biomarkers alongside LqSOFA. We evaluated the differential contribution of LqSOFA and host biomarkers to the diagnosis and prognosis of pneumonia severity. 49/900 (5.4%) presentations met the primary outcome. Discrimination of LqSOFA and Ang-2, the best performing biomarker, were comparable (AUC 0.82 [95% CI 0.76-0.88] and 0.81 [95% CI 0.74-0.87] respectively). Combining Ang-2 with LqSOFA improved discrimination (AUC 0.91; 95% CI 0.87-0.94; p < 0.001), and resulted in greater net benefit, with 10-30% fewer children who required oxygen supplementation incorrectly identified as safe for community-based management. Ang-2 had greater prognostic utility than LqSOFA to identify children requiring supplemental oxygen later in their illness course. Combining Ang-2 and LqSOFA could guide referrals of childhood pneumonia from resource-limited community settings. Further work on test development and integration into patient triage is required.

Which children with chest-indrawing pneumonia can be safely treated at home, and under what conditions is it safe to do so? A systematic review of evidence from low- and middle-income countries

Background

WHO pneumonia guidelines recommend that children (aged 2-59 months) with chest indrawing pneumonia and without any “general danger sign” can be treated with oral amoxicillin without hospital admission. This recommendation was based on trial data from limited contexts whose generalisability is unclear. This review aimed to identify which children with chest-indrawing pneumonia in low- and middle-income countries can be safely treated at home, and under what conditions is it safe to do so.

Methods

We searched MEDLINE, EMBASE, and PubMed for observational and interventional studies of home-based management of children (aged 28 days to four years) with chest-indrawing pneumonia in low- or middle-income countries.

Results

We included 14 studies, including seven randomised trials, from a variety of urban and rural contexts in 11 countries. Two community-based and two hospital-based trials in Pakistan and India found that home treatment of chest-indrawing pneumonia was associated with similar or superior treatment outcomes to hospital admission. Evidence from trials (n = 3) and observational (n = 6) studies in these and other countries confirms the acceptability and feasibility of home management of chest-indrawing pneumonia in low-risk cases, so long as safeguards are in place. Risk assessment includes clinical danger signs, oxygen saturation, and the presence of comorbidities such as undernutrition, anaemia, or HIV. Pulse oximetry is a critical risk-assessment tool that is currently not widely available and can identify severely ill patients with hypoxaemia otherwise possibly missed by clinical assessment alone. Additional safeguards include caregiver understanding and ability to return for review.

Conclusions

Home treatment of chest-indrawing pneumonia can be safe but should only be recommended for children confirmed to be low-risk and in contexts where appropriate care and safety measures are in place.

Introducing pulse oximetry in routine IMCI services in Bangladesh: A context-driven approach to influence policy and programme through stakeholder engagement

Background

Pneumonia is the leading cause of under-five child deaths globally and in Bangladesh. Hypoxaemia or low (<90%) oxygen concentration in the arterial blood is one of the strongest predictors of child mortality from pneumonia and other acute respiratory infections. Since 2014, the World Health Organization recommends using pulse oximetry devices in Integrated Management of Childhood Illness (IMCI) services (outpatient child health services), but it was not routinely used in most health facilities in Bangladesh until 2018. This paper describes the stakeholder engagement process embedded in an implementation research study to influence national policy and programmes to introduce pulse oximetry in routine IMCI services in Bangladesh.

Methods

Based on literature review and expert consultations, we developed a conceptual framework, which guided the planning and implementation of a 4-step stakeholder engagement process. Desk review, key informant interviews, consultative workshops and onsite demonstration were the key methods to involve and engage a wide range of stakeholders. In the first step, a comprehensive desk review and key informant interviews were conducted to identify stakeholder organisations and scored them based on their power and interest levels regarding IMCI implementation in Bangladesh. In the second step, two national level, two district level and five sub-district level sensitisation workshops were organised to orient all stakeholder organisations having high power or high interest regarding the importance of using pulse oximetry for pneumonia assessment and classification. In the third step, national and district level high power-high interest stakeholder organisations were involved in developing a joint action plan for introducing pulse oximetry in routine IMCI services. In the fourth step, led by a formal working group under the leadership of the Ministry of Health, we updated the national IMCI implementation package, including all guidelines, training manuals, services registers and referral forms in English and Bangla. Subsequently, we demonstrated its use in real-life settings involving various levels of (national, district and sub-district) stakeholders and worked alongside the government leaders towards carefully resuming activities despite the COVID-19 pandemic.

Results

Our engagement process contributed to the national decision to introduce pulse oximetry in routine child health services and update the national IMCI implementation package demonstrating country ownership, government leadership and multi-partner involvement, which are steppingstones towards scalability and sustainability. However, our experience clearly delineates that stakeholder engagement is a context-driven, time-consuming, resource-intensive, iterative, mercurial process that demands meticulous planning, prioritisation, inclusiveness, and adaptability. It is also influenced by the expertise, experience and positionality of the facilitating organization.

Conclusions

Our experience has demonstrated the value and potential of the approach that we adopted for stakeholder engagement. However, the approach needs to be conceptualised coupled with the allocation of adequate resources and time commitment to implement it effectively.

Hypoxaemia prevalence and management among children and adults presenting to primary care facilities in Uganda: A prospective cohort study

Hypoxaemia (low blood oxygen) is common among hospitalised patients, increasing the odds of death five-fold and requiring prompt detection and treatment. However, we know little about hypoxaemia prevalence in primary care and the role for pulse oximetry and oxygen therapy. This study assessed the prevalence and management of hypoxaemia at primary care facilities in Uganda. We conducted a cross sectional prevalence study and prospective cohort study of children with hypoxaemia in 30 primary care facilities in Uganda, Feb-Apr 2021. Clinical data collectors used handheld pulse oximeters to measure blood oxygen level (SpO2) of all acutely unwell children, adolescents, and adults. We followed up a cohort of children aged under 15 years with SpO2<93% by phone after 7 days to determine if the patient had attended another health facility, been admitted, or recovered. Primary outcome: proportion of children under 5 years of age with severe hypoxaemia (SpO2<90%). Secondary outcomes: severe (SpO2<90%) and moderate hypoxaemia (SpO2 90-93%) prevalence by age/sex/complaint; number of children with hypoxaemia referred, admitted and recovered. We included 1561 children U5, 935 children 5-14 years, and 3284 adolescents/adults 15+ years. Among children U5, the prevalence of severe hypoxaemia was 1.3% (95% CI 0.9 to 2.1); an additional 4.9% (3.9 to 6.1) had moderate hypoxaemia. Performing pulse oximetry according to World Health Organization guidelines exclusively on children with respiratory complaints would have missed 14% (3/21) of severe hypoxaemia and 11% (6/55) of moderate hypoxaemia. Hypoxaemia prevalence was low among children 5-14 years (0.3% severe, 1.1% moderate) and adolescents/adults 15+ years (0.1% severe, 0.5% moderate). A minority (12/27, 44%) of severely hypoxaemic patients were referred; 3 (12%) received oxygen. We followed 87 children aged under 15 years with SpO2<93%, with complete data for 61 (70%), finding low rates of referral (6/61, 10%), hospital attendance (10/61, 16%), and admission (6/61, 10%) with most (44/61, 72%) fully recovered at day 7. Barriers to referral included caregiver belief it was unnecessary (42/51, 82%), cost (8/51, 16%), and distance or lack of transport (3/51, 6%). Hypoxaemia is common among acutely unwell children under five years of age presenting to Ugandan primary care facilities. Routine pulse oximetry has potential to improve referral, management and clinical outcomes. Effectiveness, acceptability, and feasibility of pulse oximetry and oxygen therapy for primary care should be investigated in implementation trials, including economic analysis from health system and societal perspectives.

Improved oxygen systems at hospitals in three Nigerian states: An implementation research study

INTRODUCTION

Hypoxemia is a life-threatening condition and is commonly seen in children with severe pneumonia. A government-led, NGO-supported, multifaceted oxygen improvement program was implemented to increase access to oxygen therapy in 29 hospitals in Kaduna, Kano, and Niger states. The program installed pulse oximeters and oxygen concentrators, trained health care workers, and biomedical engineers (BMEs), and provided regular feedback to health care staff through quality improvement teams.

OBJECTIVE

The aim of this study is to evaluate whether the program increased screening for hypoxemia with pulse oximetry and prescription of oxygen for patients with hypoxemia.

METHODOLOGY

The study is an uncontrolled before-after interventional study implemented at the hospital level. Medical charts of patients under 5 admitted for pneumonia between January 2017 and August 2018 were reviewed and information on patient care was extracted using a standardized form. The preintervention period of this study was defined as 1 January to 31 October 2017 and the postintervention period as 1 February to 31 August 2018. The primary outcomes of the study were whether blood-oxygen saturation measurements (SpO₂ ) were documented and whether children with hypoxemia were prescribed oxygen.

RESULTS

A total of 3418 patient charts were reviewed (1601 during the preintervention period and 1817 during the postintervention period). There was a significant increase in the proportion of patients with SpO₂ measurements after the interventions were conducted (adjusted odds ratio [aOR] 5.0; 4.3-5.7, P < .001). Before the interventions, only 13.7% (95% confidence interval [CI]: 12.2-15.3) of patients had SpO₂ measurements and after the interventions, 82.4% (95% CI: 80.7-84.1) had SpO₂ measurements. Oxygen administration for patients with clinical signs of hypoxemia also increased significantly (aOR 5.0; 4.2-5.9, P < .001)-from 22.8% (95% CI: 18.8-27.2) to 77.9% (95% CI: 73.9-81.5).

CONCLUSION

Increasing pulse oximetry and oxygen therapy access and utilization in a low-resourced environment is achievable through a multifaceted program focused on strengthening government-owned systems.