A Retrospective Cohort to Access the Accuracy of Agitated Saline Bubble–Enhanced Ultrasound to Visualize Appropriated Position of Hemodialysis Catheter: Does Catheter Venous Site Matter?

Background: The non-tunnelled hemodialysis catheter (HDC) is commonly used to start renal replacement therapy in hospitalised patients, especially in acute kidney injury. Malposition of HDC is associated with delayed therapy and inadequate dialysis. Agitated saline bubble-enhanced ultrasound (SBUS) has become a new method to visualise catheter position at the same time of insertion. Our aim is to analyse the concordance of SBUS and chest radiography (CXR) to assess HDC position, according to the site of insertion: right vs left internal jugular vein (IJV).

Methods: From December 2019 to May 2021, we evaluated 152 hospitalized patients submitted to IJV catheter insertion. We evaluated the time from puncture to CXR result, procedure-related complications, blood flow and the accuracy of SBUS when compared to CXR to detect HDC position adequacy at both sites.

Results: The median [IQR] time between catheter insertion and CXR result was 191 [93;288] minutes, no difference between puncture sites. Complications after catheter insertion were mostly arterial puncture (2% overall), similar incidence between sites. The incidence of inadequate blood flow was higher at the left IJV than at the right IJV. For HDC at the right IJV, there was high concordance between position-adequacy assessment by SBUS and CXR ( of Gwet = 0.95, CI: 0.915; 0.992), 95.6% accuracy.  For HDC at the left IJV the concordance was low ( of Gwet 0.37, IC: -0.21; 0,94), as was accuracy (64.3%).

Conclusion: Compared with chest radiography, agitated saline bubble-enhanced ultrasound is a suitable method to check catheter placement when right internal jugular vein is used, but not left for internal jugular vein.