Dexmedetomidine vs Propofol on the Recordings of Deep Brain Activity Measured Through Implanted Stimulators
Dexmedetomidine vs Propofol on the Recordings of Deep Brain Activity Measured Through Implanted Stimulators
This clinical trial has been designed to study and compare changes in deep brain activity
 (field potentials) in Parkinson's disease (PD) patients while awake, and during sedation with
 dexmedetomidine or propofol. The recording is made through a deep brain stimulation (DBS)
 electrode implanted for PD management.

 The investigators hypothesize that dexmedetomidine produces fewer changes as compared to
 propofol, and that those changes are consistent and recognizable when compared to activity in
 patients not exposed to any sedation. Typification of those changes would in the future allow
 for patients to undergo this surgery comfortably while not compromising the quality of the
 recording and of the final clinical outcome. The principal variable analyzed is the signal's
 power in each of the frequency bands, absolute and relative. The analysis will include usual
 clinical methods such as rapid Fourier transform (FFT) and window fast Fourier transform
 (WFFT), wavelet analysis, Gabor, and coherence.
Comparative clinical trial, non blinded, controlled and sequential, evaluating the effects of
 propofol and dexmedetomidine in the basal ganglia of PD patients through a DBS electrode.

 It is a phase IV clinical trial evaluating the effects of a drug outside the approved.

 The study takes part in three phases:

 1. DBS placement under sedation with dexmedetomidine at 0.2 μg/kg/h. This will be called
 "dexmedetomidine record".

 2. Four days later and with no sedation, a recording will be registered in one of the
 specialized electrically isolated rooms at the Neurophysiology Department. This will be
 dubbed "basal recording". The equipment used is also the standard one used for routine
 postoperative recordings.

 3. 5 days after the initial surgery, and following the protocol in place for these
 procedures, the tunnelization and battery placement will take place. This is done under
 general anaesthesia. During anaesthetic induction, the patient is exposed to incremental
 doses of propofol. Different plasmatic concentrations will be targeted using the
 mathematical model in the target controlled infusion (TCI) pump. These recordings will
 be called "propofol at a 0.5, 1, 1.5, 2, 2.5 μg/mL".
Inclusion Criteria:

 -  Capacity to understand, consent and commit for the three phases of the study.

 -  Older than 18 years old.

 -  The patient is scheduled for DBS electrode placement for PD treatment by his
 neurologist.

 Exclusion Criteria:

 -  Allergy or hypersensibility to dexmedetomidine or propofol

 -  Cardiac blockade (types 2 and 3) without an implanted pacemaker

 -  Low blood pressure (mean < 60 mmHg) or symptoms of low cardiac output.

 -  Severe cerebrovascular disease.

 -  Pregnancy or nursing mothers.