Utility of Pulse Oximetry to Detect Aspiration: An Evidence-Based Systematic Review

Pulse oximetry is a commonly used means to measure peripheral capillary oxyhemoglobin saturation (SpO₂). Potential use of pulse oximetry to detect aspiration is attractive to clinicians, as it is readily available, quick, and noninvasive. However, research regarding validity has been mixed. This systematic review examining evidence on the use of pulse oximetry to detect a decrease in SpO₂ indicating aspiration during swallowing is undertaken to further inform clinical practice in dysphagia assessment. A multi-engine electronic search was conducted on 8/25/16 and updated on 4/8/17 in accordance with standards published by the Preferred Reporting for Items for Systematic Reviews and Meta-Analysis Protocols (PRISMA). Inclusion criteria included use of pulse oximetry to detect aspiration with simultaneous confirmation of aspiration via a gold standard instrumental study. Keywords included dysphagia or aspiration AND pulse oximetry. Articles meeting criteria were reviewed by two blinded co-investigators. The search yielded 294 articles, from which 19 were judged pertinent and reviewed in full. Ten met the inclusion criteria and all were rated at Level III-2 on the Australian Diagnostic Levels of Evidence. Study findings were mixed with sensitivity ranging from 10 to 87%. Potentially confounding variables were observed in all studies reviewed, and commonly involved defining "desaturation" within a standard measurement error range (~ 2%), mixed populations, mixed viscosities/textures observed during swallowing, and lack of comparison group. The majority of studies failed to demonstrate an association between observed aspiration and oxygen desaturation. Current evidence does not support the use of pulse oximetry to detect aspiration.