Differentiating Drug-related and State-related Effects of Dexmedetomidine and Propofol on the Electroencephalogram.
Anesthesiology
; 129(1): 22-36, 2018 07.
Article
in En
| MEDLINE
| ID: mdl-29642080
ABSTRACT
BACKGROUND:
Differentiating drug-related changes and state-related changes on the electroencephalogram during anesthetic-induced unconsciousness has remained a challenge. To distinguish these, we designed a rigorous experimental protocol with two drugs known to have distinct molecular mechanisms of action. We hypothesized that drug- and state-related changes can be separated.METHODS:
Forty-seven healthy participants were randomized to receive dexmedetomidine (n = 23) or propofol (n = 24) as target-controlled infusions until loss of responsiveness. Then, an attempt was made to arouse the participant to regain responsiveness while keeping the drug infusion constant. Finally, the concentration was increased 1.5-fold to achieve presumable loss of consciousness. We conducted statistical comparisons between the drugs and different states of consciousness for spectral bandwidths, and observed how drug-induced electroencephalogram patterns reversed upon awakening. Cross-frequency coupling was also analyzed between slow-wave phase and alpha power.RESULTS:
Eighteen (78%) and 10 (42%) subjects were arousable during the constant drug infusion in the dexmedetomidine and propofol groups, respectively (P = 0.011 between the drugs). Corresponding with deepening anesthetic level, slow-wave power increased, and a state-dependent alpha anteriorization was detected with both drugs, especially with propofol. The slow-wave and frontal alpha activities were momentarily disrupted as the subjects regained responsiveness at awakening. Negative phase-amplitude coupling before and during loss of responsiveness frontally and positive coupling during the highest drug concentration posteriorly were observed in the propofol but not in the dexmedetomidine group.CONCLUSIONS:
Electroencephalogram effects of dexmedetomidine and propofol are strongly drug- and state-dependent. Changes in slow-wave and alpha activity seemed to best detect different states of consciousness.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Propofol
/
Dexmedetomidine
/
Electroencephalography
/
Adrenergic alpha-2 Receptor Agonists
/
Hypnotics and Sedatives
Type of study:
Clinical_trials
Limits:
Adult
/
Humans
/
Male
Language:
En
Journal:
Anesthesiology
Year:
2018
Document type:
Article