A comparison between ultrasound guided supraclavicular and infraclavicular approach to brachial plexus block for upper limb surgery: a randomized observer blinded study

Upperlimb surgeries canbe performed under general or regional anaesthesia. Regional anaesthesiaoffers  several advantages over general  anaesthesia such as aconscious patient , avoidance of polypharmacy and airway Intervention, betterhemodynamics, good post- operative analgesia, early resumption of activities,reduced hospital stay and improved functional outcome. Brachial plexus block atthe level of the clavicle can anaesthetize all four distal upper extremitynerve territories producing an intense blockage. Supraclavicular brachialplexus block is a popular technique for upper limb surgeries because of its quickonset and high success rate.This is because at this level, thebrachial plexus elements are tightly grouped and produces a good neurologicalblock. Corner pocket sparing and thereby a less dense ulnar blockade is aproblem in supraclavicular block.  So supraclavicular blockade requires atwo point injection.  There is a  possibility of horner’s syndrome,phrenic nerve palsy and pneumothorax which may also be considered as itsdisadvantage. The main advantage of infraclavicular block isthe fewer incidences of complications with reduced the risks of inadvertentlung/pleural puncture and avoidance of injury to the neurovascular structuresin the neck. It is an ideal site for catheter technique for continuous infusionof local anaesthetics. There is lesser incidence of ulnar nerve sparing withsingle point injection. The disadvantage is that plexus is situated deeper atthis level and the angle of approach is more acute. This makes thevisualization of the relevant anatomy and the needle tip, challenging ininexperienced hands and in obese patients. Although both supraclavicularand infraclavicular blocks can be performed for upper limb surgeries,anaesthesiologists often have an inclination to supraclavicular block overinfraclavicular block because of an ease of administration. The advent ofreal time ultrasound helps in direct visualisation of nerves and theirsurrounding anatomy. It also allows for continuous   observation of the needle tip and the spread of local anaesthetics, reducedlocal anaesthetic dose required to achieve a good block, avoidance of injury tothe nearby vascular structures making ultrasound guided brachial plexus blockhighly appealing to anaesthesiologists. The rational of this study is toevaluate the efficacy of ultrasound guided infraclavicular approach of brachialplexus block compared to ultrasound guided supraclavicular approach of brachialplexus block in upper limb surgeries.