Final answer:
Blue or purple discoloration of lips and nail beds is generally a sign of low oxygen saturation in the blood. A blanch test can indicate the presence of dehydration or shock. The nail bed and its health can be assessed by looking at color changes or using specific tests.
Step-by-step explanation:
Causes of Blue Lips and Nail Beds
The discoloration of lips and nail beds to a blue or purple hue is commonly associated with low oxygen saturation in the blood. This condition, known as cyanosis, occurs when there isn't enough oxygen being delivered to the body's tissues. Healthcare providers may perform a blanch test to assess blood flow. When the capillaries under the fingernail are depressed, the nail bed turns white. If blood flow is adequate, the pink color should quickly return. A delayed return to pink may indicate issues such as dehydration or shock.
Beyond oxygen saturation, other conditions like fungal infections can also affect the health of nails, leading to thickened and yellow coloration, and products used during manicures and pedicures can sometimes be harmful if not used properly.
The cuticle of a nail is made of dead skin cells and serves as a protective barrier for the nail bed and the growth matrix. It should be noted that the nail bed itself is rich in capillaries, which are visible through the nail plate and give the nail its typical pink color when healthy and well-oxygenated.