Biomaterial Database

[Artificial ventilation, a special interaction of pulmonary mechanics and gas exchange]. 1991

A J van Vught, and K Haasnoot

Afd. Intensive Care Chirurgie, Utrecht.

During artificial ventilation the lungs are intermittently insufflated by respiratory gases in a certain pattern (ventilatory conditions). The consequences in terms of stretch of lung tissue, airway pressure, alveolar pressure and gas exchange depend on the mechanical properties of airways, lung tissue and thoracic wall. These properties are age dependent and may be changed considerably by disease. The basic principles of ventilatory support can be explained as an interaction of ventilatory gases passing through the airways in and out of the lungs, the subsequent changes in stretch of lung tissue and thoracic wall and pressure variations in the airways and alveoli. Overstretched lung and airways tissue causes damage (barotrauma, air leakage). During artificial ventilation intrathoracic pressure increases, which diminishes venous return to the heart and decreases cardiac output. In addition, the sometimes inevitably high oxygen concentrations may be toxic. In this article the ventilatory cycle is analysed into its different sequences and the interaction with the respiratory system and its consequences are discussed.

UI	MeSH Term	Description	Entries
D008168	Lung	Either of the pair of organs occupying the cavity of the thorax that effect the aeration of the blood.	Lungs
D008170	Lung Compliance	The capability of the LUNGS to distend under pressure as measured by pulmonary volume change per unit pressure change. While not a complete description of the pressure-volume properties of the lung, it is nevertheless useful in practice as a measure of the comparative stiffness of the lung. (From Best & Taylor's Physiological Basis of Medical Practice, 12th ed, p562)	Compliance, Lung,Compliances, Lung,Lung Compliances
D011312	Pressure	A type of stress exerted uniformly in all directions. Its measure is the force exerted per unit area. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Pressures
D011650	Pulmonary Alveoli	Small polyhedral outpouchings along the walls of the alveolar sacs, alveolar ducts and terminal bronchioles through the walls of which gas exchange between alveolar air and pulmonary capillary blood takes place.	Alveoli, Pulmonary,Alveolus, Pulmonary,Pulmonary Alveolus
D011659	Pulmonary Gas Exchange	The exchange of OXYGEN and CARBON DIOXIDE between alveolar air and pulmonary capillary blood that occurs across the BLOOD-AIR BARRIER.	Exchange, Pulmonary Gas,Gas Exchange, Pulmonary
D012121	Respiration, Artificial	Any method of artificial breathing that employs mechanical or non-mechanical means to force the air into and out of the lungs. Artificial respiration or ventilation is used in individuals who have stopped breathing or have RESPIRATORY INSUFFICIENCY to increase their intake of oxygen (O2) and excretion of carbon dioxide (CO2).	Ventilation, Mechanical,Mechanical Ventilation,Artificial Respiration,Artificial Respirations,Mechanical Ventilations,Respirations, Artificial,Ventilations, Mechanical
D012131	Respiratory Insufficiency	Failure to adequately provide oxygen to cells of the body and to remove excess carbon dioxide from them. (Stedman, 25th ed)	Acute Hypercapnic Respiratory Failure,Acute Hypoxemic Respiratory Failure,Hypercapnic Acute Respiratory Failure,Hypercapnic Respiratory Failure,Hypoxemic Acute Respiratory Failure,Hypoxemic Respiratory Failure,Respiratory Depression,Respiratory Failure,Ventilatory Depression,Depressions, Ventilatory,Failure, Hypercapnic Respiratory,Failure, Hypoxemic Respiratory,Failure, Respiratory,Hypercapnic Respiratory Failures,Hypoxemic Respiratory Failures,Respiratory Failure, Hypercapnic,Respiratory Failure, Hypoxemic,Respiratory Failures
D002302	Cardiac Output	The volume of BLOOD passing through the HEART per unit of time. It is usually expressed as liters (volume) per minute so as not to be confused with STROKE VOLUME (volume per beat).	Cardiac Outputs,Output, Cardiac,Outputs, Cardiac
D002648	Child	A person 6 to 12 years of age. An individual 2 to 5 years old is CHILD, PRESCHOOL.	Children
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man