Clinical Comparison Between 0.5% Bupivacaine and 0.5% Bupivacaine- Dexamethasone 8Mg Combination in Brachial Plexus Block by Supraclavicular Approach

Brachialplexusblockis apopularapproachforupperlimbsurgeriesasan alternativetogeneralanesthesia.Thistypeofanesthesiamainly helpsintoachieve idealoperatingconditionsby producingmuscularrelaxation,maintainingstableintra-operativehemodynamicconditionandsympathetic blockwhich reducespostoperative pain, vasospasm and edema. 1 Theavailableliteraturehasalsoshownthatthistypeofblockmainlyavoids theuntowardeffectsofgeneralanesthesiaincluding upperairwayinstrumentationsand thuspreventsthe consequencesofit.Ithasalso beenshownthatitisattractive due to itseffectivenessintermsofcostandperformance,marginof safety,alongwithgood postoperativeanalgesia. 2 However,supraclavicular blockisa consistentandeasiest method for anesthesia and postoperativepain management. 3-5 Bupivacaineas alocalanesthesiausedmostfrequently asithasa longerdurationofactionvarying from3to8hours.However,ithaslimitingfactors likedelayedonset,patchyorincompleteanalgesia. Tominimizethesedrawbacks many drugslikeneostigmine,opioids,hyaluronidase,midazolam,clonidine, dexamethasoneetc.havebeenaddedtolocalanestheticstoimprovethequality and duration of action and postoperative analgesia. 6-10 The steroids have been shown to reduce the inflammation and also have shownanalgesiceffects.The painreliefafter administrationof steroidsisdue to reductionofinflammationbyinhibitionofphospholipaseA 2 andalsoblocksthe transmission in nociceptiveC– fibers to reducethepain. 11 PhospholipaseA 2 has been foundtoinducemembraneinjuryandedemabygeneratinginflammatorymediators. It is the enzyme responsible for liberation of arachidonic acid leading to the productionofprostaglandinsandleukotrienes.Italsosensitizessmallneuronsand enhancespaingeneration byabnormal conductionand intraneural edema. 12 Dexamethasoneisvery potentandhighlyselectiveglucocorticoid.Clinical usesof dexamethasone are for treatmentof many inflammatory andautoimmuneconditionsbutglucocorticoidarealsousedtotreat patients suffering from neuropathic pain and complex regional pain syndromes (CRPS).