Q: When my toddler takes a nap, she sleeps on her stomach. When she wakes up, her face and eyes are red and swollen. Why? Is she allergic to something in the bed?
A: A "puffy" face on waking is common. Although we've never seen a formal explanation, we think mild swelling of the facial tissues can be explained by what is known about blood circulation.
The smallest blood vessels, the capillaries that wind their way through body tissues, are somewhat leaky. A small amount of liquid from the blood seeps out. It tends to collect where tissues are loose. The eyelids are a good example. The liquid is also pulled down by gravity, so it shows up as swelling in body parts that are "dependent" -- meaning, in medical terms, lower or nearer the ground.
When a child is sleeping on her stomach, liquid can gradually fill up loose spaces in her face. When she wakes up, the liquid drains out partly by gravity and partly by the squeezing action of her facial muscles as she begins to move them.
Facial skin can get pinker, as well as puffy, while a child sleeps if her face gets warm. To get rid of excess heat, the small blood vessels dilate (expand).
All that being said, we suspect your daughter's swollen, red face is somewhat out of the ordinary or you wouldn't have written us about it. Something in her bed may be causing a skin reaction while she sleeps. If so, it would exaggerate the normal changes we have spoken about above. Perhaps a crib toy or blanket, laundry soap that remains on the sheets or even the coarseness of the cloth is irritating her skin.
We suggest you experiment by removing all extras from the crib, changing detergents, rinsing sheets and blankets twice and line-drying them. Make certain that you are using a clean, cotton mattress pad and smooth cotton sheets. If you accomplish all that without improvement, you will need to sit down with your daughter's doctor to decide whether the problem is troublesome enough to warrant more investigation.
Dr. Wilson is director of general pediatrics at the Johns Hopkins Children's Center; Dr. Joffe is director of adolescent medicine.