Does Arterial Oxygen Desaturation as Measured by Pulse Oximetry Occur During Aspiration or Penetration in Acute Dysphagic Stroke Patients?

Abstract

Background: The high prevalence of swallowing problems and aspiration in stroke patients has been well documented. A reliable swallowing assessment that can accurately determine potential aspiration risk is necessary. The most recent adjunct to the clinical bedside assessment has been the use of pulse oximetry. Purpose: This study examines whether the use of oxygen saturation levels as measured by pulse oximetry can reliably predict the presence of aspiration or penetration of acute dysphagic stroke patients. Methods: This prospective study compared results of pulse oximetry in 20 people with dysphagia post stroke with normal controls. Fiberoptic Endoscopic Evaluation of the Swallow (FEES) was used to confirm the presence of aspiration or penetration. The FEES and pulse oximetry readings were taken simultaneously. Investigators evaluated the results of each test independently to avoid bias. Results: The results confirmed that saturation levels are lower in people with dysphagia post stroke than in the nondysphagic control group. No systematic relations between saturation levels and episodes of aspiration or penetration were found for any of the consistencies tested. Clinically significant changes in oxygen saturation are not found to predict risk of aspiration or penetration in the patient group. Measures of sensitivity (23.5%) and specificity (33.3%) are low. Conclusions: The results confirm that oxygen saturation as measured by pulse oximetry is not a reliable screening tool for identifying aspiration risk in acute stroke patients.