The Optimal Angle of Head Rotation for Internal Jugular Cannulation as Determined by Ultrasound Evaluation

Area of Science:

• Vascular anatomy
• Surgical positioning
• Medical imaging

Background:

• Understanding the spatial relationship between the internal jugular vein (IJV) and carotid artery (CA) is crucial for procedures like central venous catheterization.
• Head rotation can alter this anatomical relationship, potentially impacting procedural safety and efficacy.

Purpose of the Study:

• To determine the degree of head rotation that maximizes the anatomical separation between the right IJV and CA.

Main Methods:

• A prospective, observational cohort study was conducted at a university medical center.
• Fifty adult patients undergoing cardiac surgery were included.
• Ultrasound and digital calipers were used to measure IJV-CA separation at various head angles (-15° to +90°) in the Trendelenburg position.

Main Results:

• Maximal vertical separation of the IJV from the CA occurred at a +75° head angle, with 60.3% of the IJV being vertically unencumbered.
• This was significantly greater than at 0° (37.2%) or +15° (40.3%) head angles (p<0.01).
• Only 72% of patients could achieve the +75° position, and 54% could reach +90°.

Conclusions:

• Contralateral head rotation increases the vertical separation between the IJV and CA.
• Extreme angles of head rotation, particularly +75°, yield the greatest anatomical separation, though patient positioning limitations exist.