|ICD9= |}}Tachypnea (or "tachypnoea") (Greek: "rapid breathing")'s characterized by rapid breathing. It isn't identical with hyperventilation - tachypnea may be necessary for a sufficient gas-exchange of the body, for example after exercise, in which case it isn't hyperventilation. Tachypnea differs from hyperpnea in that tachypnea's rapid shallow breaths, while hyperpnea's rapid deep breaths. Tachypnea can also be a symptom of carbon monoxide poisoning in which oxygen delivery to the tissues… (More on Tachypnea)