[Evaluation of different protocols for the leg cuff technique for measurement of dynamic cerebral autoregulation].
OBJECTIVE
Aaslid's leg cuff method is a well validated technique to measure dynamic cerebral autoregulation. In the literature different protocols to choose cuff pressure have been described. The aim of this study is to find a technique as accurate as possible without un-necessary inconvenience for the patient.


METHODS
The leg cuff test with bilateral cuffs was performed on 10 young healthy volunteers with three different protocols (cuff pressure at systolic level, doppler controlled and 30 mmHg above systolic level). For each examination the autoregulation index invented by Tiecks and Mahony was calculated. Statistical modelling of correlated data was done with Generalized Estimating Equations.


RESULTS
The choice of the protocol influences the quality of the actual autoregulation test. The most reliable protocol is also the most inconvenient one for the patient. We found no systematic bias of the protocol on the autoregulation index, but the relation between induced blood pressure drop and resulting autoregulation index was close to statistical significance.


CONCLUSIONS
For the leg cuff test with bilateral cuffs in awake patients we recommend to apply the protocol proposed by Tiecks. Additional report of the magnitude of induced blood pressure drop would be helpful to improve the results' comparability.
Lorenz
M
M
Neurologische Klinik der Johann Wolfgang Goethe-Universität, Frankfurt am Main. matthias.lorenz@em.uni-frankfurt.de
Sterzer
P
P
Sitzer
M
M
D001794:Blood Pressure; D002560:Cerebrovascular Circulation / Q000502:physiology*; D006706:Homeostasis; D006801:Humans; D007866:Leg / Q000098:blood supply*; D015203:Reproducibility of Results; D014463:Ultrasonography / Q000379:methods*