Misaligned mechanical ultrasound transducer contributes to carotid puncture

This report describes a complication from the use of a mechanical ultrasound transducer and needle guide to perform internal jugular cannulation. Misalignment of the probe led to an inability to visualize the needle and accidental carotid puncture. Placement of the central line was successful with landmark technique, and there were no sequelae. The transducer design explains how such misalignment may occur if the crystal oscillation is not symmetric. The manufacturer recommends periodic testing for probe alignment, and awareness of this potential problem may help other users avoid patient injury with this type of ultrasound transducer.