RT Journal Article SR Electronic T1 Ultrasound guidance for peripheral nerve blocks: an observational trend study of national data JF Regional Anesthesia & Pain Medicine JO Reg Anesth Pain Med FD BMJ Publishing Group Ltd SP 681 OP 683 DO 10.1136/rapm-2019-101113 VO 45 IS 9 A1 Haskins, Stephen C A1 Fiasconaro, Megan A1 Wilson, Lauren A1 Poeran, Jashvant A1 Liu, Jiabin A1 Memtsoudis, Stavros YR 2020 UL http://rapm.bmj.com/content/45/9/681.abstract AB