The utility of transthoracic echocardiography to confirm central line placement: an observational study.

BACKGROUND

Ultrasound visualization of neck vessels is the standard method used to assist with internal jugular vein (IJV) central line placement. Nevertheless, this practice has not eliminated the risk of carotid puncture and/or inadvertent arterial cannulation. Transesophageal echocardiography (TEE) effectively verifies wire placement within the heart but is invasive and not always available. We examined the feasibility and potential utility of using transthoracic echocardiography (TTE) to verify the distal wire in the right atrium (RA) before dilation and cannulation of the IJV.

METHODS

Following institutional Research Ethics Board approval and signed consent, 100 patients scheduled for elective cardiac surgery were recruited. As per standard practice at our institution, all patients were to have a central line inserted under general anesthesia with TEE visualization of the guidewire. Transesophageal echocardiography (apical or subcostal four-chamber images) was performed by one of four operators while another anesthesiologist performed central line placement. Following IJV puncture, blood was rapidly aspirated and reinjected to produce microbubbles. Subsequently, a 0.035-inch j-tipped flexible guidewire was inserted and visualized with TEE. The wire was then reinserted into the RA under TTE visualization.

RESULTS

Overall, the RA was viewed 94% (95% confidence interval [CI] 87 to 98) of the time with TTE, and both the microbubbles and guidewire were detected 91% (95% CI 84 to 96) of the time. The subjects in whom the guidewire could not be well visualized had a higher mean body mass index (33.6 vs 28.8; P = 0.01).

CONCLUSIONS

Transthoracic echocardiography [corrected] is a feasible, noninvasive, and potentially useful method to confirm appropriate placement of the guidewire before dilation and cannulation of the IJV.