Pulse oximeters are noninvasive devices that measure blood oxygen saturation and pulse rate. They are used to help health care workers detect hypoxemia – a low level of oxygen in the blood – and to know how much medical oxygen to administer to patients. While pulse oximeters that fit on a patient’s finger are the most common, there are several other types including hand-held, phone-based, and wearable models. When fingertip sensors don’t work well for infants or very young children, there are alternatives like toe sensors, earlobe sensors, or even wrap-around foot sensors that ensure more accurate readings despite smaller body parts or more delicate skin.

Because they are portable and non-invasive, pulse oximeters are particularly suitable for use at the primary care level. Detecting hypoxemia can allow timely treatment, including with oxygen therapy when needed, and save hundreds of thousands of lives each year. For example, during the COVID-19 pandemic, pulse oximeters were crucial for triaging COVID-19 patients and identifying those in need of urgent care and medical oxygen therapy, especially when hospital resources were scarce.

Pulse oximeters are an essential component of a strong health system. Understanding technological challenges, existing and pipeline products, and market challenges is key for facilitating equitable access to pulse oximeters and for Unitaid’s efforts to support countries to address medical oxygen gaps in their health systems in line with the WHO resolution on increasing access to medical oxygen in 2023. To help enable the scale-up of pulse oximeters in primary health care, Unitaid supported research to evaluate the feasibility, cost-effectiveness and impact of expanding the use of pulse oximeters for use by primary health workers in low-resource settings. The studies demonstrated good acceptance of pulse oximeters by health care providers and showed that to improve health outcomes, introduction of pulse oximeters needs to be integrated as part of “whole of systems” approach and not as a standalone intervention.

Unitaid and PATH also published the “Next generation pulse oximeters: technology and market landscape report” in 2022, which assessed the potential of multimodal pulse oximeter devices – devices that can measure oxygen levels and other vital statistics like respiratory rate, temperature, and/or hemoglobin – to improve the integrated diagnosis and treatment of illnesses for patients presenting at health facilities in low- and middle-income countries, with a focus on maternal and child health. During the COVID-19 pandemic, we delivered more than 5,000 pulse oximeters to health facilities in low- and middle-income countries. Through our support for the Open Oximetry Project, we have also worked to address challenges in existing pulse oximeters that have been shown to overestimate oxygen saturation in the blood of patients with darker skin pigmentation – which can lead to delayed or inadequate medical treatment, with potentially fatal consequences.