Comparison of two doses of dexmedetomidine as adjuvent to 0.5% Ropivacaine in ultrasound guided brachial plexus block in upper limb surgeries-A Randomised Control Trail

In today’s world brachial plexus block has evolved as an important part of dailyroutine anaesthesiology practice as an substitute to general anaesthesia for upper limb surgeries. This mode of anaesthesia is also considered safe due to its application with an ultrasound guided live imaging. Also, it aids patient in form of providing post operative analgesia and reducing hospital stay that helps patient financially also.

The first supraclavicular block was performed in 1912 by kulen kampff byconventional parasthesia technique blind technique. Giving regional anaesthesia by blind technique has an high failure risk and risk of damaging vital anatomical structures. Ultrasound guided regional anaesthesia eliminates this drawback of blind technique.2 In 1978 La Grange introduced application of doppler probe to identify arteries .

In regional anaesthesia we use a local anaesthesia that is used to block the brachialplexus. These local anaesthetics have limited duration of action and providing post operativeanalgesia. Ropivacaine being a long acting amino amide is one of foremost drug used inbrachial plexus block. Ropivacaine when compared with bupivacaine and levobupivacainehas lower lipid solubility and hence provide greater sensory and motor blockade duration and also motor function recovery is fast.

Ropivacaine when compared with other local anaesthetic like bupivacaine and levobupivacaine is less cardiac and central nervous system toxic drug. It acts on voltage gatedsodium channels that blocks peripheral afferents.

Even with use of Ropivacaine it was found that duration of analgesia was limited andpatients complained of post operative pain and opiod administration was required to prolongpost operative analgesia duration. So use of adjuvents with  local anaesthetic came into existence such as dexmedetomidine, clonidine, opioids and neostigmine. These helped toprolong post operative analgesia. Opioids are known to cause various side effects like apnea,respiratory suppression, hypoxia so dexmedetomidine provides anaesthesiologists with abetter alternative to opoids and helps to elinminates these side effets.

Dexmedetomidine is an alpha 2 receptor blocker agonist that can be used as anadjuvent to local anaesthetic in order to prolong duration of post operative analgesia and to decrease time of onset . Dexmedetomidine has analgesic, sedative antihypertensive and anaesthetic sparing properties that contributes multimodaly. Dexmedetomidine as alpha 2agonist is highly selective (more than 8 times selective as compared to clonidine ) as an adjuvant.

Previous studies are present that have compared various local anaesthetics alone andwith combination with adjuvents in brachial plexus blocks for upper limb surgeriesindividually. To our comprehension few study are known to have compared effects ofropivacaine in regional anaesthesia in brachial plexus block in combination with two differentdosages of dexmedetomidine, and access results of these two groups.