Desaturatie

Desaturatie is a term used to describe a reduction in saturation. In medical contexts it refers to a decrease in the oxygen saturation of arterial blood, commonly measured as SpO2. In photography and image processing, desaturatie denotes the lowering of color saturation, which makes colors appear more muted or grayscale.

In healthy individuals, arterial oxygen saturation is typically 95–100%. Desaturatie can be detected with pulse oximetry, which estimates SpO2 from light transmitted through a fingertip. Arterial blood gas analysis provides direct measurements of SaO2. Desaturatie can be acute or chronic and may be transient during sleep or exertion.

Causes include lung diseases (COPD, pneumonia, asthma), acute respiratory distress syndrome, pulmonary edema, pulmonary embolism, altitude exposure, and ventilation–perfusion mismatch. Cardiac conditions, anemia, or impaired hemoglobin function can also affect oxygen-carrying capacity. Clinically, desaturation signals reduced oxygen delivery to tissues and may require intervention.

Management focuses on treating the underlying cause and ensuring adequate oxygenation, often starting with supplemental oxygen and close monitoring. Thresholds for intervention vary; SpO2 targets depend on patient factors, but values persistently below 90% are generally concerning and may require escalation, such as noninvasive or invasive ventilation.

In imaging, desaturation reduces chroma and can be used as an artistic effect or as part of color analysis. In color spaces such as HSV/HSB or HSL, saturation is a coordinate that can be reduced to produce desaturated or grayscale images.