Biomaterial Database

A mathematical expression to describe the ventilatory response to hypoxia and hypercapnia. 1977

A S Rebuck, and A S Slutsky, and C K Mahutte

A mathematical expression has been developed to describe the ventilatory responses to changes in arterial oxygen saturation (SaO2) and arterial carbon dioxide tension (PCO2). The derivation is based on the experimental observations: (1) that ventilation is a linear function of PCO2 under isoxic conditions, and (2) that ventilation is a linear function of SaO2 under isocapnic conditions. It is assumed that all functions are continuous and single valued, with the implication that for any given SaO2 and PCO2 there is a unique ventilatory response. The analysis following from these three assumptions has enabled us to derive the following expression for ventilation: VI(SaO2, PCO2) = alpha1 - SaO2 - PCO2 + alpha2 - SaO2 + alpha3 - PCO2 + alpha4 where the alpha's are constants for an individual. This equation, which follows uniquely from the assumption stated, is simpler and contains fewer parameters than previous expressions used to describe ventilation.

UI	MeSH Term	Description	Entries
D008433	Mathematics	The deductive study of shape, quantity, and dependence. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Mathematic
D008954	Models, Biological	Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.	Biological Model,Biological Models,Model, Biological,Models, Biologic,Biologic Model,Biologic Models,Model, Biologic
D012119	Respiration	The act of breathing with the LUNGS, consisting of INHALATION, or the taking into the lungs of the ambient air, and of EXHALATION, or the expelling of the modified air which contains more CARBON DIOXIDE than the air taken in (Blakiston's Gould Medical Dictionary, 4th ed.). This does not include tissue respiration (	Breathing
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D006935	Hypercapnia	A clinical manifestation of abnormal increase in the amount of carbon dioxide in arterial blood.
D000860	Hypoxia	Sub-optimal OXYGEN levels in the ambient air of living organisms.	Anoxia,Oxygen Deficiency,Anoxemia,Deficiency, Oxygen,Hypoxemia,Deficiencies, Oxygen,Oxygen Deficiencies