Introduction. Cerebral vasoreactivity (CVR) is the mechanism that maintains stable cerebral blood flow in response to cerebral metabolic variations or systemic blood pressure. The reference method for studying CVR is transcranial Doppler (TCD) using a vasodilator stimulus. A simple alternative to perform is the apnea test, but its results can be influenced by physiological variables and the height at which the subject is.
The objective of this study was to determine normal CVR values in a group of people residing in Quito.
Material and Methods. 48 people without a history of disease were examined. Flow parameters in the middle cerebral and basilar arteries were recorded. With the results of the apnea test, the percentage increase in flow velocity and the Breath Holding Index were calculated. This data was analyzed by sex and the age group.
Results. The average age was 34.8 years, with a predominance of those under 40 years of age and women (70.8%). Higher Vmf were recorded in women. CVR was significantly higher in the MCA (p 0.000) and lower in women. With age, flow parameters and apnea test results did not demonstrate significant differences.
Conclusions. In the cohort examined, the hemodynamic parameters recorded during the apnea test offer different results than those published in other series. The lower RVC appears to be influenced by altitude and sex.
