Pulmonary edema
Flash pulmonary edema is a medical emergency.  It is pulmonary edema that comes on very quickly.  Usually pulmonary edema takes a few hours to develop.  But in the worst cases of flash pulmonary edema, a person's lungs can fill completely with fluid in minutes.  Flash pulmonary edema can also be caused by moving a person with pulmonary edema, or lying them down.