Abstract
Part 1 comments on the types of local anaesthetics (LAs); it provides a better understanding of the mechanisms of action of LAs, and their pharmacokinetics and toxicity. It reviews the newer LAs such as levobupivacaine, ropivacaine, and articaine, and examines the newer structurally different LAs. The addition of adjuvants such as adrenaline, bicarbonate, clonidine, and corticosteroids is explored. Comment is made on the delivery of topical LAs via bioadhesive plasters and gels and controlled-release local anaesthetic matrices. Encapulation matrices such as liposomes, microemulsions, microspheres and nanospheres, hydrogels and liquid polymers are discussed as well. New innovations pertaining to LA formulations have indeed led to prolonged action and to novel delivery approaches.
Highlights
Local anaesthetics (LAs) are used clinically for anaesthesia and analgesia either following surgery or for management of other acute and chronic pain conditions; they only last a few hours
Lignocaine is perhaps most commonly used or known local anaesthetic agent; it is used either in local or regional anaesthesia, or in epidural or spinal blockade; it has a number of uses in anaesthesia and pain medicine
Injectable local anaesthetics are subject to absorption; a large fraction of the injected drug is removed by the systemic circulation and distributed to distant organs according to their vascular density [9]
Summary
Local anaesthetics (LAs) are used clinically for anaesthesia and analgesia either following surgery or for management of other acute and chronic pain conditions; they only last a few hours. Local anaesthesia for a prolonged period of days is best provided using catheter techniques [1] with disposable pumps [2] or multiple injections [3]. Most attempts to prolong LA action have so far only doubled or tripled the plain drug effect time, using adjuncts to LA agents of readily available agents. These include opioids and clonidine that delay local anaesthetic clearance from their site of action [4] and dexamethasone that prolongs peripheral nerve and plexus blocks [5]
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have