Accuracy of Pulse Oximetry in Dark-skinned Patients

Lisa Smith, RN, DNP, CRNA

DNP Nurse Anesthesia

Accuracy of Pulse Oximetry in Dark-skinned Patients

Project Category:  Evidence Synthesis 

Project Team: Lisa Smith, DNP, CRNA Guada Carter DNP, CRNA Michael Ledvina CRNA, DNAP, Jennifer Greenwood CRNA, PhD (Advisor)

Abstract

Background: Pulse oximetry is the most common non-invasive tool used to monitor oxygenation in healthcare settings; unfortunately, the accuracy of pulse oximetry was not tested in a diverse population prior to its widespread utilization. Inaccurate readings could lead to misinterpretation of oxygenation and a potential mismanagement of respiratory interventions to correct hypoxemia. The purpose of this systematic review was to determine the accuracy of pulse oximetry in adult patients with dark skin pigmentation in comparison to fair skin.

Methods: A systematic review was conducted by first utilizing a systematic search of PubMed, OVID MEDLINE, and CINAHL. The inclusion criteria for this review consisted of adult subjects, and studies that compared pulse oximetry (SpO2) to arterial oxygen saturation (SaO2). All study designs were considered. Each study was evaluated independently by two reviewers using the JBI Critical Appraisal Checklist and data was extracted.

Results: A total of fourteen articles were included in this review, including a pooled sample of 122,300 subjects. The articles composed of six non-randomized quasi-experimental, two cohort,

two observational, and four retrospective cohort studies. Each study investigated bias, defined as the difference between SpO2 and SaO2. Eleven studies revealed that there was increased bias in subjects with darker skin complexions compared to fair-skinned counterparts; the range of bias among these studies was 0.6% to 5.4% and -0.2% to 3.2%, respectively.

Conclusions: All articles evaluated confirm that pulse oximetry is less accurate in subjects of darker skin. Clinicians should have a lower threshold for utilizing other methods to evaluate oxygenation in darker-skinned patients, especially when there is increased suspicion of hypoxemia.

Full Manuscript Slide Presentation Video