PHARMACOKINETICS AND PHARMACODYNAMICS OF PROPOFOL AND DEXMEDETOMIDINE DURING ELECTIVE PROCEDURAL SEDATIONS AND CHARACTERISTICS OF THEIR COMBINATION (LITERATURE REVIEW)

Abstract

In the previous publication, we outlined the general principles of procedural sedation (PS), the depth of suppression of consciousness and spontaneous motor activity, the minimum quantity of patients' pre-procedural examinations and the aspects of informed consent obtaining. The principles of vital signs monitoring, patients' immobilisation, and the detection and treatment of adverse events have been described. A key aspect of the PS is the readiness to ensure patency of the airways and oxygenation at least one level deeper than the existing level of the PS.
 In this publication, attention is focused on the pharmacokinetics and pharmacodynamics of propofol and dexmedetomidine - the main drugs for elective PS and on the combination between them. In a future publication, we plan to characterize other key medications for PS, such as midazolam, ketamine, thiopental, and fentanyl.
 Propofol is a short-track anaesthesia drug, and it was the most widely distributed in the 21st century because after its use patients quickly and fully regain consciousness. At the same time, to achieve the necessary deep level of sedation and prevent unintended movements of the patient, it is often required to use high doses of propofol that can cause clinically significant suppression of the patency of the upper respiratory airways, depth of breathing, and hemodynamic. Therefore, in this publication, we promote the implementation of multimodal sedation and analgesia with the use of moderate doses of several drugs, which allows a significant reduction in the dose of propofol and thus increase the safety of PS. Dexmedetomidine has both sedative and analgesic properties with a minimal effect on the patency of the upper airways and the depth of breathing, thus is the best drug to combine with propofol in PS.
 In children, intranasal administration of dexmedetomidine and midazolam is an important alternative method of premedication, which provides a gentle entry into sedation and prevents the child's stress reactions to the placement of a venous catheter. Although the use of dexmedetomidine in children's practice is still "off-label" and outside the indications approved by the FDA in this publication we provide evidence to justify its safety and effectiveness of its usage in paediatrics PS.