There are several causes of shortness of breath (dyspnea) that clinical signs and symptoms may indicate certain diseases. Here I will explain the clinical types of dyspnea.
2. Pulmonary: Two pulmonary causes of dyspnea is restrictive defect with pulmonary spasticity or lower thoracic wall and obstructive defect with increased resistance to air flow. Patients with restrictive dyspnea (such as pulmonary fibrosis or thoracic deformity) usually feels comfortable at rest but becomes very dyspnea on activities cause pulmonary ventilation reaches the largest limit breathing capacity. On obstructive dyspnea (eg on obstuktif emphysema or asthma), increased efforts ventilation causing dyspnea, although at rest and breathing seemed difficult and restrained, especially during expiration.
3. Cardiac: In the early stages of heart failure. Cardiac output failed to keep pace with the increase in metabolic demand, which increases during exercise. Thus boost respiration increased primarily due to acidosis and cerebral tissue, and patients to hyperventilate. Various factors reflexes, including the stretch receptors in the lungs, may also play a role in hyperventilation. Shortness of breath is often accompanied by malaise or feeling suffocated. In the advanced stages of heart failure, pulmonary congestion and edema experience, capacity decreased lung ventilator, and efforts to increase ventilation. Reflex factors, especially juxtacapillary receptors (J) in the alveolar-capillary septum, contribute to improving pulmonary ventilation. Non-cardiogenic pulmonary edema or adult respiratory distress syndrome (ARDS) would cause a similar clinical picture through the same mechanism, but more acute. Cardiac asthma is a condition of acute respiratory insufficiency with bronchospasm, wheezing and hyperventilation. This situation may be indistinguishable from other types of asthma, but the cause is the failure of the left ventricle. Respiration periodic or Cheyne-Stokes characterized by periods of apnea and hyperpnea alternating regularly, often include a component of neurological disorders in the medullary respiratory center and cardiology component. In heart failure, slowing circulation is the dominant cause; acidosis and hypoxia in the respiratory center also plays a role. Orthopnea is respiratory disorder that occurs when the patient is lying down, thus forcing to sit. This situation triggered by an increase in venous return to the left ventricular failure and not able to handle this increased preload. Sometimes orthopnea occurs in other cardiovascular disorders (eg, pericardial effusion). Paroxysmal nocturnal dyspnea (PND), the patient is awake with gasping and must sit down and stand up to restore breathing that may be dramatic or frightening. The same factors that cause orthopnea also contribute to this form of respiratory distress. PND can occur in mitral stenosis, aortic insufficiency, hypertension and other conditions affecting the left ventricle.
4. Circulation: Air Hunger (acute dyspnea which occurs in the terminal stages of bleeding) is a bad sign that requires immediate transfusion. Dyspnea also occurs in chronic anemia, which occurs only during exercise, unless anemia is extreme.
5. Chemical: Diabetic acidosis (blood pH from 7.2 to 6.95) led to patterns of respiration slow and deep (Kussmaul breathing). But, because of respiratory capacity is maintained properly, patients rarely complain of dyspnea, otherwise uremic patients may complain of dyspnea because of fainting due to a combination of acidosis, heart failure, pulmonary edema and anemia.
6. Central: cerebral lesions (eg, bleeding) is often accompanied by strong hyperventilation that is sometimes noisy and great. Sometimes the unexpected happens period in the form of apnea, irregular, with periods of 4 or 5 breathing with a similar depth (Biot's respiration). Hyperventilation also common after a head injury. Decrease in PaCO2 causes reflex CNS vasoconstriction with decreased cerebral perfusion secondary cause a decrease in intracranial pressure.
7. Psychogenic: Overbreating hysterical type often found. At one of its kind, continuous hyperventilation sometimes cause acute alkalosis due to "blowing off" CO2; Chvostek trousseau sign and a positive result from a decrease in serum calcium ion levels. Another type is characterized by a deep respiration in which patients breathe with the maximum depth until respiration is "satisfied" that the current impulse hyperventilation disappeared. This situation is often repeated.