Impact of Neck Position on the Probability of Common Carotid Artery Puncture During Ultrasound-Guided Stellate Ganglion Block.

BACKGROUND: The carotid artery must be avoided during stellate ganglion block. However, information on optimal neck position during the ultrasound-guided approach is limited.

OBJECTIVE: To investigate the relation between the target area of the procedure and the carotid artery in different neck positions.

DESIGN: Observational study.

SETTING: Tertiary university.

PARTICIPANTS: A total of 30 sides of the neck from 18 healthy participants were included.

METHODS: An ultrasound transducer was placed at the level of the anterior tubercle of C6 with a short-axis view for measuring the distance from the tip of the C6 anterior tubercle to the margin of the carotid artery. The participants were first examined through ultrasonography in 3 different rotational neck positions (neutral, semicontralateral rotation, and full-contralateral rotation), in the supine position. After changing to the lateral decubitus position, the measurement was performed again in the same 3 neck positions.

MAIN OUTCOME MEASURES: The C6 anterior tubercle to carotid distance was measured with ultrasound.

RESULTS: The C6 anterior tubercle to carotid distance was the longest with full-contralateral neck rotation (P < .05). The distance was longer in the semicontralateral neck rotation compared with the neutral neck position (P < .05). Supine or decubitus positions did not affect the distance.

CONCLUSIONS: We suggest that the full-contralateral neck rotation posture in either the supine or decubitus position is most beneficial for avoiding damage to the carotid artery during the ultrasound-guided stellate ganglion block.

LEVEL OF EVIDENCE: Not applicable.