Cerebral hypoxia historical perspective
Anika Zahoor M.D.[1] NOTOC__
|
Cerebral hypoxia Microchapters |
|
Diagnosis |
|---|
|
Treatment |
|
Case Studies |
|
Cerebral hypoxia historical perspective On the Web |
|
American Roentgen Ray Society Images of Cerebral hypoxia historical perspective |
|
Risk calculators and risk factors for Cerebral hypoxia historical perspective |
Overview
The relationship between brain function and blood flow has been studied since the classical paper of Roy and Sherrington (61) at the end of the 19th century.
Historical Perspective
- Despite the absence of quantitative methods, early investigators were able to establish some of the basic principles of the cerebral circulation; among these was a recognition of the dominating influence of carbon dioxide and the reciprocal effect of oxygen (72).
- Interestingly, even the idea that local cerebral blood flow (CBF) was transiently augmented with increased neuronal activation, alluded to by Roy and Sherrington, had received additional qualitative experimental support.
- A listing of the qualitative methods in use at the time, including methods such as venous outflow, radium emanation, and thermocouple, can be found in the 1936 Wolff review (72).
- Nevertheless, despite more than 100 years of effort, there are still major areas concerning the control of the cerebral circulation that remain unknown.
- The observations that decreasing oxygen led to increased blood flow and that the increase was blunted perhaps by the accompanying hypoxia-induced hyperventilation and resultant decreased carbon dioxide remained wholly qualitative until a useful quantitative method, based on inert gases, was developed for measuring CBF and oxygen metabolism by Kety and Schmidt (33, 35).