PRO AND CONTRA ON ADJUVANTS TO NEUROAXIAL ANESTHESIA AND PERIPHERAL NERVE BLOCKS.

Abstract

Modern approach in surgical treatment and in managing acute and chronic pain is nowadays more and more based on the implementation of all possible techniques of regional anesthesia (RA). Local anesthetics (LA) are needed to achieve standard regional anesthesia. Local anesthetics are primarily characterized by time constraints and duration of action, and depending on the amount applied, adverse effects on the cardiac and central nervous system may occur. Adjuvants are drugs used together with LA due to their synergistic effect, i.e. they improve start latency and duration of sensory and motor blockade and enable reduction of cumulative dose of LA and reduction of adverse effects on cardiac and nervous system. Nowadays, there is a huge variety of drugs that can be administered in combination with LA, and they, in general, can be divided into opioid and non-opioid adjuvants. The administration of opioids in RA over an extended time period was accompanied by some negative characteristics as respiratory depression, nausea, vomiting. So, their usage is still under a special control. Due to the positive effects shown by drugs from non-opioid adjuvants group (e.g. adrenaline, alpha adrenergic agonists, steroids, magnesium, midazolam, ketamine etc.), indications for their administration broadened. However, there are still some restrains in clinical practice based on the fact that neurotoxicity and demonstration of neurological complications in regional anesthesia haven't been properly researched yet.