Original contribution Comparison of the diameter, cross-sectional area, and position of the left and right internal jugular vein and carotid artery in adults using ultrasound ☆,☆☆,★ Michaël J. Bos MD a , Rick F.H.J. van Loon MSc b , Luke Heywood MBBS, FANZCA c , Mitchell P. Morse BAppSc, MBBS (Qld), FANZCA c , André A.J. van Zundert MD, PhD, FRCA, EDRA, FANZCA (Professor of Anaesthesia) c, ⁎ a Department of Anaesthesiology, Maastricht University Medical Centre, Maastricht, the Netherlands b Department of Anaesthesiology, Catharina Hospital Eindhoven, Eindhoven, the Netherlands c The University of Queensland & Royal Brisbane & Women's Hospital, Department of Anaesthesia and Perioperative Medicine, Herston Campus, Brisbane, Qld 4029, Australia Received 14 May 2015; accepted 22 December 2015 Keywords: Anatomy; Left internal jugular vein; Right internal jugular vein; Carotid artery; Ultrasound Abstract Study objective: Central venous access is indicated for transduction of central venous pressure and the administration of inotropes in the perioperative period. The right internal jugular vein (RIJV) is cannulated preferentially over the left internal jugular vein (LIJV). Cannulation of the LIJV is associated with a higher complication rate and a perceived increased level of difficulty when compared with cannulation of the RIJV. Possible explanations for the higher complication rate include a smaller diameter and more anterior position relative to the corresponding carotid artery (CA) of the LIJV compared with the RIJV. In this study, the RIJV and LIJV were examined in mechanically ventilated patients to determine the validity of these possible explanations. Design: A prospective, nonrandomized cohort study. Setting: The operating room of a major teaching hospital. Patients: One hundred fifty-one patients scheduled for elective heart surgery. Intervention: Ultrasound examination of the RIJV and LIJV at the level of the cricoid cartilage with a 12-MHz linear transducer in 151 anesthetized, mechanically ventilated patients in the Trendelenburg position. Measurements and results: In 72% of patients, the RIJV was dominant over the LIJV. The diameter and cross- sectional area of the RIJV was larger than the LIJV (P b .001). An anterior position of the LIJV in relation to the left CA was detected more often when compared with the RIJV and right CA (15.1% vs 5.4%, P = .01). ☆ Trial Registration: Clinical trials ID NCT01599299. ☆☆ Sources of financial support: Department funds only. ★ No financial disclosures to make. ⁎ Corresponding author at: Department of Anaesthesia and Perioperative Medicine, RBWH Ned Hanlon Building level 4, Butterfield St, Herston Campus, Brisbane, QLD 4029, Australia. Tel.: + 61 736465673; fax: + 61 736461308. E-mail addresses: bos_michiel@yahoo.com (M.M.J. Bos), rick.v.loon@catharinaziekenhuis.nl (R.F.H.J. van Loon), luke.heywood@health.qld.gov.au (L. Heywood), mitchellmorse@hotmail.com (M.P. Morse), vanzundertandre@gmail.com, a.vanzundert@uq.edu.au (A.A.J. van Zundert). http://dx.doi.org/10.1016/j.jclinane.2015.12.034 0952-8180/© 2016 Elsevier Inc. All rights reserved. Journal of Clinical Anesthesia (2016) 32, 65–69