Effect of the Location of Tetanic Stimulation on Autonomic Responses: A Randomized Cross-Over Pilot Study.

Background: Tetanic stimuli are used as standardized noxious inputs to investigate nociception. Previous studies have applied tetanic stimuli to various anatomical locations without validating that the resulting physiological responses were independent of the location where tetanic stimuli were applied. Our aim was to investigate the effects of three anatomical tetanic stimulus application sites on physiological variables reflecting autonomic nervous system responses as measured by photoplethysmography (PPG).

Electroencephalographic Arousal Patterns Under Dexmedetomidine Sedation.

Background: The depth of dexmedetomidine-induced sedation is difficult to assess without arousing the patient. We evaluated frontal electroencephalogram (EEG) as an objective measure of dexmedetomidine-induced sedation. Our aims were to characterize the response patterns of EEG during a wide range of dexmedetomidine-induced sedation and to determine which spectral power best correlated with assessed levels of dexmedetomidine-induced sedation.

Pharmacokinetics and pharmacodynamics of dexmedetomidine-induced vasoconstriction in healthy volunteers.

Aims: Alpha-2 agonists are direct peripheral vasoconstrictors, which achieve these effects by activating vascular smooth muscle alpha-2 adrenoceptors. The impact of this response during dexmedetomidine infusion remains poorly quantified. Our goal was to investigate the pharmacokinetic (PK) and pharmacodynamic (PD, vasoconstriction) effects of a computer-controlled dexmedetomidine infusion in healthy volunteers.

The Effect of Tracheal Intubation-Induced Autonomic Response on Photoplethysmography.

. Intraoperative stress responses and postoperative pain can be monitored using photoplethysmography (PPG). PPG signal has two components, AC and DC.