oxyhemoglobin dissociation curve

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Related to oxyhemoglobin dissociation curve: oxyhemoglobin saturation, Haldane effect


a line that is not straight, or that describes part of a circle, especially a line representing varying values in a graph.
dose-effect curve (dose-response curve) a graphic representation of the effect caused by an agent (such as a drug or radiation) plotted against the dose, showing the relationship of the effect to changes in the dose.
growth curve the curve obtained by plotting increase in size or numbers against the elapsed time.
oxyhemoglobin dissociation curve a graphic curve representing the normal variation in the amount of oxygen that combines with hemoglobin as a function of the partial pressures of oxygen and carbon dioxide. The curve is said to shift to the right when less than a normal amount of oxygen is taken up by the blood at a given Po2, and to shift to the left when more than a normal amount is taken up. Factors influencing the shape of the curve include changes in the blood pH, Pco2, and temperature; the presence of carbon monoxide; alterations in the constituents of the erythrocytes; and certain disease states.
pulse curve sphygmogram.
Spee curve (curve of Spee) the anatomic curvature of the occlusal alignment of teeth, beginning at the tip of the lower canine, following the buccal cusps of the premolars and molars, and continuing to the anterior border of the ramus.
strength-duration curve a graphic representation of the relationship between the intensity of an electric stimulus at the motor point of a muscle and the length of time it must flow to elicit a minimal contraction; see also chronaxie and rheobase. In cardiac pacing it is useful in determining characteristics of a particular pacing electrode and determining the most efficient selection of pacing parameters for an appropriate safety margin.
survival curve a graph of the probability of survival versus time, commonly used to present the results of clinical trials, e.g., a graph of the fraction of patients surviving (until death, relapse, or some other defined endpoint) at each time after a certain therapeutic procedure.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

ox·y·he·mo·glo·bin dis·so·ci·a·tion curve

(ok'sē-hē'mŏ-glōb'in di-sō'sē-ā'shŭn kŭrv)
A graphic illustration of the relationship between oxygen saturation of hemoglobin and the partial pressure of arterial oxygen (PaO2); the position and overall shape of this sigmoidal curve are affected by the hydrogen ion concentration (pH), body temperature, partial pressure of carbon dioxide (PCO2), and organic phosphates.
Synonym(s): oxyhaemoglobin dissociation curve, oxyhaemoglobin dissociation curve.
Medical Dictionary for the Health Professions and Nursing © Farlex 2012
References in periodicals archive ?
Corresponding values for S[O.sub.2] were calculated from an expression for the standard oxyhemoglobin dissociation curve (3)].
The value of [P.sub.50] determined from an excellent mathematical model of the oxyhemoglobin dissociation curve under standard conditions of 37[degrees]C, pH 7.40, P[CO.sub.2] = 5.33 kPa (40 mmHg), and a 2,3-diphosphoglycerate concentration of 5.0 mmol/L is 3.56 kPa (26.7 mmHg) (3).
On the oxyhemoglobin dissociation curve, an SaO2 of 90% equals a PaO2 of 60 mm Hg.