Arterial Oxygen Saturation: A Vital Sign?

Area of Science:

• Medical Diagnostics
• Pulmonology
• Critical Care Medicine

Background:

• Physical examination is integral to patient care, from initial assessment to treatment outcomes.
• Understanding the pathophysiology of physical signs is crucial for accurate diagnosis and timely management.
• Vital signs, including pulse rate, respiratory rate, body temperature, and blood pressure, are fundamental bedside measurements.

Purpose of the Study:

• To highlight the importance of arterial oxygen saturation (SaO2) as a vital sign.
• To review the clinical utility and application of pulse oximetry in patient care.
• To emphasize the role of physiological understanding and clinical expertise in interpreting diagnostic signs like SaO2.

Main Methods:

• Literature search on arterial oxygen saturation and its significance as a vital sign, primarily in PubMed.
• Review and analysis of available studies on pulse oximetry's clinical applicability.
• Extraction of data from relevant articles to support the discussion.

Main Results:

• Pulse oximetry is effective for non-invasive measurement of arterial oxygen saturation (SpO2).
• Studies confirm the clinical utility of pulse oximetry in early detection of hypoxemic events.
• Arterial oxygen saturation, especially when trended with respiratory rate, offers a comprehensive view of respiratory status.

Conclusions:

• Arterial oxygen saturation, measured by pulse oximetry, is increasingly recognized as the fifth vital sign.
• Accurate interpretation of SaO2, informed by physiological knowledge, is essential for effective clinical decision-making.
• During the COVID-19 pandemic, SpO2 has proven to be a critical warning and prognostic indicator across various settings.