Sunday, December 13, 2009

Effect of head up tilt on cerebral circulation.

Acta Astronaut. 1994 Jul;33:69-76.
Effect of head up tilt on cerebral circulation.

Yoshimoto S, Ueno T, Mayanagi Y, Sekiguchi C, Yumikura S, Miyamoto A, Yajima K.

Dept. of Neurosurgery, Tokyo Police Hospital, Japan.

This study was performed to study the effect of the head up tilt (HUT) on cerebral circulation across the time course (60 degrees HUT for 15 minutes) and across the different angles of HUT (15, 30, 45, 60 degrees HUT for 15 minutes). Cerebral circulation was continuously monitored during 15 minutes of HUT by the carotid Doppler flow meter, the transcranial Doppler flow meter, and the near infra-red spectrophotometer. The results show that the cerebral blood flow decreased during HUT and that the cerebral blood volume decreased initially and then gradually increased. And the magnitude of the effect may have the relationship with the angles of the HUT.

PMID: 11539540 [PubMed - indexed for MEDLINE]


rpav said...

Is this study suggesting that having the head raised on pillows would have this negative effect?

Andrew K Fletcher said...

I think the paper refers to tilting the whole bed at different angles over a short period and relates to the blood flow in relation to these changes.

All of the angles used were far more acute than the 5 degrees used in Inclined Therapy. It does lend to a question about where I.T becomes less efficient.