Hyperventilation (rapid deep breathing)
Hyperventilation is the breathing response kicked off by an acute panic attack or anxiety attack. Hyperventilation causes the amount of carbon dioxide (CO2) in the blood to drop too low. Hyperventilation: Overbreathing. This can cause dizziness, lightheadedness, weakness, shortness of breath, a sense of unsteadiness, muscle spasms in the hands and feet, and tingling around the mouth and fingertips. All of these symptoms are the result of abnormally low levels of carbon dioxide in
the blood caused by overbreathing.
In normal breathing, both the depth and frequency of breaths is varied by the neural system in order to balance the flow of oxygen into the body with the flow of carbon dioxide out of the body. The gasses in the alveoli are nearly in equilibrium with the gasses in the blood. At rest, less than 10% of the gas in the alveoli is replaced each breath. Deeper breaths exchange more of the alvolar gas with air and have the net effect of drawing more carbon dioxide out of the body, since the carbon dioxide concentration in normal air is very low. This respiratory control is the first, most powerful, and most rapid mechanism acting to control body pH. A rise in pH will be countered by retention of carbon dioxide (shallower breaths) until pH is restored by the resulting increase in carbonic acid. The normal person is not consciously aware of this constant regulatory activity. Of course the kidneys are essential to long term regulation, because sulphate and nitrate ions, for instance, can not be gassified, but the kidneys operate on a much slower time scale.
Hyperventilation is an unreasoning rapid breathing associated with psychological shortness of breath or feeling of smothering and is one of the symptom complex of a panic attack. It feeds on itself by producing a marked lowering of the pCO2 (carbon dioxide levels) with an associated drop of blood calcium levels resulting in tetany (spastic loss of muscle function). This results in a vicious cycle — pushing the diver into a peripheral narrowing and locked into panic driven behavior. Rapid breathing can also be caused by faulty equipment, causing a retention of CO2. Hyperventilation is often due to anxiety or panic. Other less common causes include stimulant use; excessive use of aspirin; pulmonary disease such as asthma, chronic obstructive pulmonary disease (COPD), and pulmonary embolism; infection such as pneumonia or sepsis; heart disease such as congestive heart failure or heart attack; pain; and ketoacidosis when diabetes is out of control.
In many cases, hyperventilation can be controlled with home treatment.Reassurance can help relax breathing. Breathing in and out of a paper bag (to increase the level of carbon dioxide in the blood) is no longer recommended (because the level of carbon dioxide can rise too high).