RT Journal Article SR Electronic T1 International consensus on anatomical structures to identify on ultrasound for the performance of basic blocks in ultrasound-guided regional anesthesia JF Regional Anesthesia & Pain Medicine JO Reg Anesth Pain Med FD BMJ Publishing Group Ltd SP rapm-2021-103004 DO 10.1136/rapm-2021-103004 A1 James Simeon Bowness A1 Amit Pawa A1 Lloyd Turbitt A1 Boyne Bellew A1 Nigel Bedforth A1 David Burckett-St Laurent A1 Alain Delbos A1 Nabil Elkassabany A1 Jenny Ferry A1 Ben Fox A1 James L H French A1 Calum Grant A1 Ashwani Gupta A1 William Harrop-Griffiths A1 Nat Haslam A1 Helen Higham A1 Rosemary Hogg A1 David F Johnston A1 Rachel Joyce Kearns A1 Sandra Kopp A1 Clara Lobo A1 Sonya McKinlay A1 Stavros Memtsoudis A1 Peter Merjavy A1 Eleni Moka A1 Madan Narayanan A1 Samer Narouze A1 J Alison Noble A1 David Phillips A1 Meg Rosenblatt A1 Amy Sadler A1 Maria Paz Sebastian A1 Alasdair Taylor A1 Athmaja Thottungal A1 Luis Fernando Valdés-Vilches A1 Thomas Volk A1 Simeon West A1 Morné Wolmarans A1 Jonathan Womack A1 Alan James Robert Macfarlane YR 2021 UL http://rapm.bmj.com/content/early/2021/09/22/rapm-2021-103004.abstract AB There is no universally agreed set of anatomical structures that must be identified on ultrasound for the performance of ultrasound-guided regional anesthesia (UGRA) techniques. This study aimed to produce standardized recommendations for core (minimum) structures to identify during seven basic blocks. An international consensus was sought through a modified Delphi process. A long-list of anatomical structures was refined through serial review by key opinion leaders in UGRA. All rounds were conducted remotely and anonymously to facilitate equal contribution of each participant. Blocks were considered twice in each round: for “orientation scanning” (the dynamic process of acquiring the final view) and for the “block view” (which visualizes the block site and is maintained for needle insertion/injection). Strong recommendations for inclusion were made if ≥75% of participants rated a structure as “definitely include” in any round. Weak recommendations were made if >50% of participants rated a structure as “definitely include” or “probably include” for all rounds (but the criterion for “strong recommendation” was never met). Thirty-six participants (94.7%) completed all rounds. 128 structures were reviewed; a “strong recommendation” is made for 35 structures on orientation scanning and 28 for the block view. A “weak recommendation” is made for 36 and 20 structures, respectively. This study provides recommendations on the core (minimum) set of anatomical structures to identify during ultrasound scanning for seven basic blocks in UGRA. They are intended to support consistent practice, empower non-experts using basic UGRA techniques, and standardize teaching and research.