Gareth Parry1. 1. Department of Anesthesia, University of British Columbia, Vancouver, British Columbia, Canada. garethandantonia@ntlword.com
Abstract
PURPOSE: The right internal jugular (RIJ) is commonly used to provide central venous access, and success of cannulation shows a positive correlation with the vein's diameter. The purpose of this study is to establish the patient position resulting in the largest RIJ diameter. METHOD: 2D ultrasound was used to measure RIJ diameter, in varying body positions, in 21 healthy volunteers. RESULTS: In the neutral position (table flat, head on the table in midline) the RIJ diameter was (mean +/- standard deviation) 9.2 +/- 2.18 mm. A small pillow under the head increased RIJ diameter (10.6 +/- 2.16 mm, P < 0.001). Trendelenburg tilt of 15 degrees increased RIJ diameter (12.1 +/- 2.34 mm, P < 0.001). In the Trendelenburg position (15 degrees of tilt), a small pillow under the head further increased RIJ diameter (13.3 +/- 2.26, mm P < 0.001), palpating for the carotid artery decreased RIJ diameter (8.2 +/- 1.98 mm, P < 0.001), and rotation of the head 45 degrees to the left did not reduce RIJ diameter significantly (11.7 +/- 2.52 mm, P = 0.12). CONCLUSION: The patient position to achieve maximal RIJ diameter cannulation is: 15 degrees of Trendelenburg tilt; a small pillow or head ring under the head; the head in or close to midline; and after palpation of the carotid artery, it should be released prior to vein cannulation.
PURPOSE: The right internal jugular (RIJ) is commonly used to provide central venous access, and success of cannulation shows a positive correlation with the vein's diameter. The purpose of this study is to establish the patient position resulting in the largest RIJ diameter. METHOD: 2D ultrasound was used to measure RIJ diameter, in varying body positions, in 21 healthy volunteers. RESULTS: In the neutral position (table flat, head on the table in midline) the RIJ diameter was (mean +/- standard deviation) 9.2 +/- 2.18 mm. A small pillow under the head increased RIJ diameter (10.6 +/- 2.16 mm, P < 0.001). Trendelenburg tilt of 15 degrees increased RIJ diameter (12.1 +/- 2.34 mm, P < 0.001). In the Trendelenburg position (15 degrees of tilt), a small pillow under the head further increased RIJ diameter (13.3 +/- 2.26, mm P < 0.001), palpating for the carotid artery decreased RIJ diameter (8.2 +/- 1.98 mm, P < 0.001), and rotation of the head 45 degrees to the left did not reduce RIJ diameter significantly (11.7 +/- 2.52 mm, P = 0.12). CONCLUSION: The patient position to achieve maximal RIJ diameter cannulation is: 15 degrees of Trendelenburg tilt; a small pillow or head ring under the head; the head in or close to midline; and after palpation of the carotid artery, it should be released prior to vein cannulation.