Keeping the blood at the proper level of oxygen saturation can be difficult in the case of a newborn or a premature baby and it's generally the case that pulse oximeters will be employed on a regular basis to keep tabs on the baby's saturation level. A severe de-saturation may cause the baby's lips to turn blue and may also impact the color of the skin. The baby's body might also become floppy or lacking in tone. In these cases a baby must be fed additional oxygen so as to enhance his or her oxygen saturation level.