With normal blood pressure and heart and lungs, why does one wake up breathless during sleep.?

Many reasons. If someone is obese or has some type of airway obstruction, this may can cause what is called obstructive sleep apnea, also gastric content regurgitation that goes to the lungs due gastroesophageal reflux may cause someone to wake up catching their breath.
Heart or lung diseas. Waking up breathless during sleep is always a serious medical problem that involves either the heart or lungs. It is never normal. The only instance in which someone would wake up breathless and have no medical problem is if they were having a nightmare or night terror. Otherwise, this condition should always be taken very seriously since it is caused either by serious heart or lung disease.

Related Questions

I get occasional palpitations. I haven't had them in weeks, but having them now after drinking hot chocolate. I feel breathless. I usually only have them after being active. My heart beats normal and have normal blood pressure. What should I do?

Anxiety disorder. Coco has some elements of caffine. But if you have normal BP and hr, it's ok. Read more...
Chocolate. Cocoa/chocolate can cause palpitations. Your symptoms suggest a rapid heart rhythm disorder (tachyarrhythmia). Ask your doctor for a 24 hour recorder (holter) or, if it happens less frequently, a 30 day event monitor to document what your heart is actually doing. Treatment hinges on this documentation. Get your thyroid and electrolytes checked. Avoid caffeine (coffee, cola, and chocolate). Read more...
Palpitation Sx. Palpitations are an awareness of extra heartbeats which most of us have. The sensation can be single or multiple and can sometimes last minutes. Different people may feel other symptoms along with them such as dizzy, lightheaded or short of breath. The palpitations are almost always atrial or ventricular premature beats. Usually benign but they are also found with abnormal hearts. Read more...