Correlation between the arterial pulse wave of the cerebral microcirculation and CBF during breath holding and hyperventilation in human.

OBJECTIVE

To evaluate if relative changes in the amplitude of the arterial pulse wave of the cerebral microcirculation (APWCM) measured by near-infrared spectroscopy (NIRS) may provide information about relative changes of cerebral blood flow (CBF) in cerebral cortex.

METHODS

In 10 healthy human volunteers, through simultaneous recording of the APWCM amplitude by means of NIRS and the mean blood flow velocity (MBFV) of middle cerebral artery by means of transcranial Doppler (TCD) at rest and during breath holding and hyperventilation, we evaluate a possible correlation between relative changes of the mean APWCM amplitude and relative changes of MBFV.

RESULTS

We found a significant linear correlation: breath holding: R(2) 0.84, p < 0.001, hyperventilation: R(2) 0.81, p<0.001.

CONCLUSION

The relative changes of the mean APWCM amplitude seem able to provide information about relative changes of CBF of cerebral cortex in healthy adult humans during breath holding and hyperventilation.

SIGNIFICANCE: APWCM detected by NIRS, a safe, repeatable, inexpensive technology and at the bedside may improve the study of cerebral cortex microcirculation in neurological diseases.