| peak expiratory flow | The maximum flow at the outset of forced expiration, which is reduced in proportion to the severity of airway obstruction, as in asthma. (05 Mar 2000) |
|---|---|
| peak expiratory flow rate | Measurement of the maximum rate of airflow attained during a forced vital capacity determination. Common abbreviations are pefr and pfr. (12 Dec 1998) |
| positive end-expiratory pressure | A technique used in respiratory therapy in which airway pressure greater than atmospheric pressure is achieved at the end of exhalation by introduction of a mechanical impedance to exhalation. (05 Mar 2000) |
| negative end-expiratory pressure | A subatmospheric pressure at the airway at the end of expiration. (05 Mar 2000) |
| expiratory | <physiology> Pertaining to, or employed in, the expiration or emission of air from the lungs; as, the expiratory muscles. Source: Websters Dictionary (01 Mar 1998) |
| expiratory centre | The region of the medulla oblongata that is electrically active during expiration and where electrical stimulation produces sustained expiration. (05 Mar 2000) |
| expiratory dyspnea | Difficulty with the expiratory phase of breathing, often due to obstruction in the larynx or large bronchi, such as by a foreign body. (05 Mar 2000) |
| expiratory resistance | Resistance to flow of gas out of the lungs or the total resistance to flow of gas during the expiratory phase of the respiratory cycle. (05 Mar 2000) |
| expiratory stridor | A singing sound due to the semi-approximated vocal folds offering resistance to the escape of air. (05 Mar 2000) |
| zero end-expiratory pressure | Airway pressure which, at the end of expiration, equals atmospheric pressure. (05 Mar 2000) |
| atomic volume | The atomic weight of an element divided by its density in the solid state; the volume of the gram-atomic weight of a solid element. (05 Mar 2000) |
| blood volume | Volume of circulating blood. It is the sum of the plasma volume and erythrocyte volume. (12 Dec 1998) |
| blood volume determination | Method for determining the circulating blood volume by introducing a known quantity of foreign substance into the blood and determining its concentration some minutes later when thorough mixing has occurred. From these two values the blood volume can be calculated by dividing the quantity of injected material by its concentration in the blood at the time of uniform mixing. Generally expressed as cubic centimeters or liters per kilogram of body weight. (12 Dec 1998) |
| blood volume nomogram | A nomogram used to predict blood volume on the basis of the individual's weight and height. (05 Mar 2000) |
| cardiac volume | The volume of the heart, usually relating to the volume of blood contained within it at various periods of the cardiac cycle. The amount of blood ejected from a ventricle at each beat is stroke volume. (12 Dec 1998) |