Does pulse oximeter use impact health outcomes? A systematic review

Abstract

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.

Keywords: Evidence Based Medicine; Health services research; Outcomes research; Paediatric Practice; Respiratory.

Figure 1

Flow chart showing the study selection process. See online supplementary appendix II for the Characteristics of Included Studies table and online supplementary appendix III for the Characteristics of Excluded Studies table.

Figure 2

Simple, hypothetical illustration of introducing pulse oximetry into primary care or walk-in clinical settings illustrating the trade-offs that may be apparent in terms of increased or decreased referral or admission rates based on plausible (low and high) estimates of existing rates and true prevalence of hypoxaemia. Note that in low-income countries children often have multiple acute respiratory infections (ARI) episodes per year. The estimates for the baseline (when pulse oximeters are not used) were the following: low estimate for referral rates from primary care facilities: 100 (1%); high estimate: 500 (5%); low estimate for admission from emergency department (ED): 500 (5%); high estimate: 1500 (15%). Referral and admission rates for when pulse oximeters are used were estimated by assuming an increase or decrease in primary care referrals/ED admissions of 5–50% over or below the baseline referral/admission rates. Hypoxaemia prevalence in children aged 7 days–36 months presenting to an ED with ARI has been shown to be as high as 59% (when hypoxaemia defined as SaO₂<91%) so these high estimates for referral/admission rates are reasonable. Referral/admission rates would be higher in a population if: the true hypoxaemia prevalence in the population is higher (eg, due to high altitude, seasonal effects on bronchiolitis, predisposing environmental factors for asthma); a larger proportion of hypoxaemic children are being missed by clinical evaluation; or higher thresholds are used to define hypoxaemia. The converse of these conditions would lead to lower referral/admission rates, as would a reduction in the number of false-positives as a result of improved accuracy of hypoxaemia diagnosis over clinical signs.