Exspiráció

Exspiráció is the act of exhalation in respiration, the phase during which air is expelled from the lungs. It is the counterpart to inspiráció (inhalation). The term comes from Latin exspiratio and is used in Hungarian medical literature alongside kilégzés; in everyday language kilégzés is typically preferred.

Physiology of exspiráció varies with breathing effort. During quiet or resting breathing, exspiráció is largely passive, driven by the elastic recoil of the lungs and chest wall after the diaphragm and inspiratory muscles relax. In forced or active exhalation, expiratory muscles such as the internal intercostals and abdominal muscles actively decrease thoracic volume to accelerate air release, which is important during speaking, coughing, or intense exercise.

Measurement and clinical relevance. Exspiráció is central to spirometry, where parameters such as forced expiratory volume in one second (FEV1), forced vital capacity (FVC), and expiratory reserve volume (ERV) are derived from the exhaled air. Capnography and other assessments analyze the composition and flow of air during exspiráció to evaluate ventilation efficiency. Abnormal exspiráció patterns can indicate respiratory disease: obstructive conditions like COPD and asthma often show prolonged or effortful exhalation and reduced expiratory flow, while restrictive disorders can reduce overall exhaled volumes. Aging may also affect expiratory muscle strength and flow rates.

See also. Related terms include inspiráció, kilégzés, spirometry, and clinical measures such as FEV1, FVC, and ERV.