Comparison Of Supraclavicular Brachial Plexus Block With Different Injection Methods

Objective: Supraclavicular brachial plexus block is considered as one of the most effective anesthetic methods for surgeries in the forearm.Its disadvantage,is the risk of pneumothorax,vascular puncture,Horner's syndrome,due to inaccurate placement of the needle.Ultrasound-guided technique may reduce the risk of complications and increase the success rate of block.In this prospective,randomized,observer-blinded study,we compared double-injection(DI)and multiple-injection(MI)techniques to perform supraclavicular brachial plexus block.Methods:Select eighty patients who were schedule for operation of forearm or wrist or hand,ASA physical status ?to ?,male or female,and body mass index between 17.5-28.5kg/m2,were randomly allocated to receive a DI(n=40)or MI(n=40)technique ultrasound-guided supraclavicular block.Those patients with psychotic disorder,local anesthetics allergy,and history of supraclavicular fossol operatopn were excluded before the operation.The local anesthetic drug(lidocaine 2% 10 ml and ropivacaine0.5% 10ml)were prepared for all patients,In both groups,with ultrasoundguided,half the volume was injected inside the main neural cluster.For the DI technique,redirection the needle,deposite the second 10 ml anesthetic drug at the “corner pocket”(intersection of the first rib and subclavian artery).In contrast,for the MI technique,the remaining 10 ml was divided into equal volume and injected inside every single neural cluster.For instance,if 2,3,4,or 5 clusters were identified;aliquots of 5,3.3,2.5or 2 ml were used,respectively.The main outcome we observe was the total anesthesia-related time(sum of performance and onset times).Give cold test and motor test on dominant place of radial,ulnar,median and musculocutaneous nerves.Take records of performance time,needle passes,onset time,success rate,and adverse events.Results: Due to a quicker onset(P<0.05),the total anesthesia-related time was shorter with the MI technique(P<0.05).The 2 methods achieved comparable success rate;There was no surgical failures for both groups.The DI group required fewer needle passes(P<0.05)and shorter performance times(P<0.05).No intergroup differences were observed in duration of anesthesia and adverse events(P>0.05).Conclusion: DI and MI ultrasound-guided supraclavicular blocks seem to provide comparable success rates.MI spend more performance time,but due to quicker onset,the MI technique block results in a shorter total anesthesia-related time.Both groups have similar duration of analgesia,and there was no adverse enent happened during the operation in both groups.