We call it “Hyperventilation” when a person involuntarily, and subconsciously, breathes a lot faster than they need to. “Than they need to” means that nothing is stopping the body from obtaining enough oxygen, like diseases of the heart, lungs, or circulation. Other conditions may make a person breathe fast, like fever, hyperthyroidism, or too much acid in the blood (diabetic ketoacidosis, severe kidney failure, certain poisonings). That’s not what we mean.
In other words, with Hyperventilation, the person is completely well physically, but simply begins to breathe fast, sometimes very fast. It’s invariably due to anxiety or panic, for reasons that may or may not be consciously realized.
Our key to diagnosis is that exertion doesn’t make the breathing worse, and may often improve it. Whenever the body can’t get enough oxygen, breathing always gets harder with exertion. It’s impossible to lack oxygen at rest for whatever reason, then go for a brisk walk with ease. See our definition of “true” shortness of breath.
People hyperventilating get enough oxygen, but breathe out too much carbon dioxide, much more than they need to. This can produce a variety of symptoms, including:
- sense of being short of breath
- lightheadedness or dizziness
- tingling of the hands and lips
- chest tightness
- rarely crampy spasms of the hands or feet
- in rare cases, passing out
Of course, a heart attack or serious lung disease can cause many of these same symptoms, but not the tingling. When this is present, we clue in to the diagnosis. Still, the main criterion is always that the patient’s sense of shortness of breath does not worsen with exertion.
Physical examination is completely normal with Hyperventilation, no signs of any serious disease. Most specifically, there are no respiratory retractions. These refer to where the skin sucks in with each breath, meaning our respiratory muscles are being forced to work extra. This is seen between the ribs in children, or in adults if lung disease is severe. We look for milder degrees in the hollows above the collarbones, and in the small notch where the neck meets the breastbone. Since our oxygen is always normal with Hyperventilation, there couldn’t possibly be any reason for the body to overwork.
Similarly, if we check a hyperventilating person’s oxygen saturation (“O2 Sat”) with a little device called a pulse oximeter, which slips on a finger or maybe ear lobe, it’s by definition normal. Normal means ≥95%. Abnormal is <90%, while 90-94% are equivocal (can’t really tell).
Since the medical history is always the most important component of diagnosis, we wouldn’t diagnose Hyperventilation if we had reason to suspect other causes of shortness of breath. It would be a risky diagnosis in a person with risk factors for, say, a Heart Attack or Pulmonary Embolism, or Type-1 Diabetes. See our topic Shortness of Breath.
Hyperventilation tends to recur, so a history of past episodes lasting minutes to hours helps convince us. But every chronic symptom has its beginning, so a first episode is always tricky. Since underlying anxiety resolves with sleep, attacks don’t last longer than a day. Another may occur again the next day, but would be triggered at some point, not simply present upon awakening.
Treatment for hyperventilation attacks involves addressing the underlying anxiety. There are many methods, from medication to therapy to acupuncture and more.
One “gimmick” many clinicians have practiced (myself included) is to have the patient place a small paper bag over their mouth, and breathe in and out of it. It serves to calm, and can reverse symptoms by breathing back in the carbon dioxide that’s being lost. This may sound risky, and certainly is if we aren’t sure of our diagnosis. We’d only perform it while constantly observing the patient, and expect it to help very soon. But once a person has had several attacks and has used it with success, it’s a handy home remedy. As a disclaimer, major medical resources like “Up-To-Date” and “Medscape” (“eMedicine”) strongly discourage paper bags, lest they be used prior to achieving a solid diagnosis.