Extrafascial Catheter Tip Placement For Continuous interscalene Brachial Plexus Block Reduces Hemidiaphragmatic Paresis Compared With a Conventional intrafascial Tip Placement : a Randomized, Controlled, Double-Blind Trial

Background and Goal of StudyPerineural dexamethasone has gained popularity in regional anaesthesia to prolong analgesia duration, but its advantage over systemic administration is disputed. The objective of this meta-analysis was to compare the analgesic efficacy of both routes of administration during peripheral nerve blockade.Materials and MethodsThe methodology followed the PRISMA statement guidelines. The primary outcome was duration of analgesia analysed according to the type of local anaesthetic administered (bupivacaine or ropivacaine). Secondary outcomes included cumulative opioid consumption in intravenous morphine equivalents, pain scores and complications rates (neurologic complication, infection, hyperglycaemia).Results and DiscussionEleven controlled trials, including 914 patients, were identified. Duration of analgesia was significantly increased with perineural dexamethasone versus systemic dexamethasone by a mean difference of 3h (95%CI: 1.4, 4.5 h; p=0.0001). Subgroup analysis reveals that the duration of analgesia was increased by 21% with bupivacaine (mean difference: 4.0 hours; 95%CI: 2.8, 5.2 hours; p