Edema has many possible causes: 1  Prolonged standing or sitting, especially in hot weather, can cause excess fluid to accumulate in the feet, ankles and lower legs. 2  Tiny valves inside the veins of the legs can become weakened, causing a common problem called venous insufficiency.
Cars with nitrous-equipped engines can be identified by the purge of the delivery system that most drivers perform prior to reaching the starting line. A separate electrically operated valve is used to release air and gaseous nitrous oxide trapped in the delivery system.
Nitrous Oxide is a sweet smelling, non irritating, colorless gas which you can breathe. Nitrous Oxide has been the primary means of sedation in dentistry for many years. Nitrous oxide is safe; the patient receives 50-70% oxygen with no less than 30% nitrous oxide.Patients are able to breathe on their own and remain in control of all bodily functions.hough there are no major contraindications to using nitrous oxide, you may not want to use it if you have emphysema, exotic chest problems, M.S., a cold or other difficulties with breathing. You may want to ask your dentist for a 5 minute trial to see how you feel with this type of sedation method before proceeding.