| Vd/Vt | dead space ventilation/total ventilation [ratio] |
|---|---|
| VR | right arm [electrode]; valve replacement; variable ratio; vascular resistance; venous reflux; venous... |
| Auto-PEEP | self-controlled positive end-expiratory pressure |
| CCRT | computer-controlled radiation therapy |
| CCT | carotid compression tomography; central conduction time; cerebrocranial trauma; chocolate-coated tab... |
| ventilation/perfusion mismatch | An imbalance between alveolar ventilation and pulmonary capillary blood flow. (05 Mar 2000) |
|---|---|
| ventilation-perfusion ratio | The ratio of alveolar ventilation to simultaneous alveolar capillary blood flow in any part of the lung. (12 Dec 1998) |
| ventilation/perfusion ratio | The ratio of alveolar ventilation to simultaneous alveolar capillary blood flow in any part of the lung; because both ventilation and perfusion are expressed per unit volume of tissue and per unit time, which cancel, the units become liters of gas per liter of blood. (05 Mar 2000) |
| ventilation-perfusion scan | A lung function test, especially useful for pulmonary embolism, employing an inhaled radionuclide for ventilation and an intravenous radionuclide for perfusion; their respective distributions in the lung are recorded scintigraphically. (05 Mar 2000) |
| ventilation perfusion scanning | <investigation, radiology> A nuclear medicine test that involves the inhalation of a radioactive gas and the injection of a radioactive compound into the bloodstream. A special camera measures the radioactive compound and generates a image of the lungs. Comparisons are made between the images generated. Pulmonary embolism can be diagnosed using this procedure. (12 Jan 1998) |
| maximal voluntary ventilation | Measure of the maximum amount of air that can be breathed in and blown out over a sustained interval such as 15 or 20 seconds. Common abbreviations are mvv and mbc. (12 Dec 1998) |
| maximum voluntary ventilation | The volume of air breathed when an individual breathes as deeply and as quickly as possible for a given time (e.g., 15 sec.). Synonym: maximum breathing capacity. (05 Mar 2000) |
| mechanical ventilation | <anaesthetics> Mechanically assisted breathing using a electrically powered device that forces oxygenated air into the lungs and then allow time for passive exhalation of air. (27 Sep 1997) |
| middle ear ventilation | Ventilation of the middle ear in the treatment of secretory (serous) otitis media, usually by placement of tubes or grommets which pierce the tympanic membrane. (12 Dec 1998) |
| wasted ventilation | That part of the pulmonary ventilation which is ineffective in exchanging oxygen and carbon dioxide with pulmonary capillary blood; calculated as physiologic dead space multiplied by respiratory frequency. (05 Mar 2000) |
| continuous positive pressure ventilation | Synonym: controlled mechanical ventilation. (05 Mar 2000) |
| high-frequency jet ventilation | Respiratory support system used primarily with rates of about 100 to 200/min with volumes of from about one to three times predicted anatomic dead space. Used to treat respiratory failure and maintain ventilation under severe circumstances. (12 Dec 1998) |
| high-frequency ventilation | Ventilatory support system using frequencies from 60-900 cycles/min or more. Three types of systems have been distinguished on the basis of rates, volumes, and the system used. They are high frequency positive-pressure ventilation (hfppv), high-frequency jet ventilation (hfjv), and high-frequency oscillation (hfo). (12 Dec 1998) |
| pulmonary ventilation | The process of exchange of air between the lungs and the ambient air. Pulmonary ventilation is a measure of the rate of ventilation expressed usually in liters per minute. (12 Dec 1998) |
| spontaneous intermittent mandatory ventilation | Intermittent mandatory ventilation spontaneously initiated by the patient, to increase tidal volume, and subsequently synchronised with patient's respiratory cycle. Synonym: synchronised intermittent mandatory ventilation. (05 Mar 2000) |