The SMART needle. A new Doppler ultrasound-guided vascular access needle.

Central venous access is an essential part of patient management in many clinical settings. Traditionally this has been achieved by a blind, external landmark guided technique which may not correlate exactly with the location of the vessel. We have prospectively evaluated the SMART needle, a new Doppler ultrasound guided vascular access device, in 40 patients, to evaluate whether it can improve on the standard technique. The SMART needle was easy to use and reliably distinguished between arterial and venous signals. No advantage was demonstrated in 'easy' internal jugular vein cannulations. Although ease of cannulation in difficult cases was subjectively improved, the differences in time to cannulation and number of passes between the groups failed to reach statistical significance and the complication rates were similar. However, the use of the SMART needle on two occasions enabled avoidance of carotid artery puncture by correctly distinguishing the artery from the vein, so that it may have a rôle in patients in whom difficult internal jugular venous cannulation is anticipated.