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The Impact of Trendelenburg Position and Positive End-Expiratory Pressure on the Internal Jugular Cross-Sectional Area

BACKGROUND: Increasing the cross-sectional area (CSA) of the right internal jugular vein facilitates cannulation and decreases complications. Maneuvers such as the Trendelenburg tilt position and ventilation with a positive end-expiratory pressure (PEEP) may increase the CSA of the right internal jugular vein. We determined the changes in the CSA in response to different maneuvers. METHODS: The CSA (cm2) of the right internal jugular vein was assessed in 50 anesthetized adult cardiothoracic surgery patients using 2-dimensional ultrasound. First, the CSA was measured in response to supine position with no PEEP (control condition, S0) and compared with 5 different randomly ordered maneuvers: (1) PEEP ventilation with 5 cm H2O (S5), (2) PEEP with 10 cm H2O (S10), (3) a 20° Trendelenburg tilt position with a PEEP of 0 cm H2O (T0), (4) a 20° Trendelenburg tilt position combined with a PEEP of 5 cm H2O (T5), and (5) a 20° Trendelenburg tilt position combined with a PEEP of 10 cm H2O (T10). RESULTS: All maneuvers increased the CSA of the right internal jugular vein with respect to the control condition S0 (all P < 0.05). S5 increased the CSA on average by 15.9%, S10 by 22.3%, T0 by 39.4%, T5 by 38.7%, and T10 by 49.7%. CONCLUSION: In a comparison of the effectiveness of applying different PEEP levels and/or the Trendelenburg tilt position on the CSA of the right internal jugular vein, the Trendelenburg tilt position was most effective.