The rapid atrial swirl sign for ultrasound-guided tip positioning of antegrade-tunneled hemodialysis catheters: A cross-sectional pilot study

BACKGROUND

We have previously reported that the rapid atrial swirl sign (RASS) is an accurate and safe procedure for ultrasound (US)-guided tip positioning of retrograde-tunneled hemodialysis catheters (HDCs). However, application of RASS for placement of antegrade HDCs has not been investigated yet. Therefore, we here report our first experience of applying RASS for US-guided tip positioning of antegrade-tunneled HDCs.

METHODS

We performed a cross-sectional study to assess the feasibility of applying the RASS for US-guided tip positioning of antegrade-tunneled HDCs. We included a total number of 15 antegrade-tunneled HDC insertions in 13 patients requiring placement of a HDC for the temporary or permanent treatment of ESKD in a single-center, cross-sectional pilot study.

RESULTS

The overall success rate of applying the RASS for US-guided tip positioning of antegrade-tunneled HDCs was 15/15 (100%) confirmed by portable anterior-posterior chest radiography, with no major adverse events after HDC insertions. In addition, this insertion technique demonstrated optimal HDC flow without any observed malfunction.

CONCLUSION

This study investigated the efficacy of the RASS for US-guided tip positioning of antegrade-tunneled HDCs in patients with ESKD. Application of the RASS for US-guided tip positioning is an accurate and safe procedure for proper placement of antegrade-tunneled HDCs.

Myocardial Enhancement Following Agitated Saline Contrast Study in a Boxer Dog

•Myocardial enhancement after agitated saline contrast study in a dog is described. •Suspect air microemboli can inadvertently be introduced into coronary vasculature. •Air microemboli are a theoretic risk of saline contrast echocardiography.

The Rapid Atrial Swirl Sign for Ultrasound-Guided Tip Positioning of Retrograde-Tunneled Hemodialysis Catheters: A Cross-Sectional Study from a Single Center

Background: Chronic kidney disease (CKD) is a common medical problem in patients worldwide, with an increasing prevalence of patients with end-stage kidney disease (ESKD) requiring renal replacement therapy (RRT). In patients requiring RRT for more than two weeks or those who develop ESKD, tunneled hemodialysis catheter (HDC) insertion is preferred, based on a lower risk for infectious complications. While the efficacy of ultrasound (US)-guided tip positioning in antegrade-tunneled HDCs has previously been shown, its application for the insertion of retrograde-tunneled HDCs has not been described yet. This is especially important, since the retrograde-tunneled technique has several advantages over the antegrade-tunneled HDC insertion technique. Therefore, we here report our first experience of applying the rapid atrial swirl sign (RASS) for US-guided tip positioning of retrograde-tunneled HDCs. Methods: We performed a cross-sectional study to assess the feasibility of applying the RASS for US-guided tip positioning of retrograde-tunneled HDCs. We performed a total number of 24 retrograde-tunneled HDC insertions in 23 patients (requiring placement of a HDC for the temporary or permanent treatment of ESKD) admitted to our Department of Nephrology and Rheumatology at the University Medical Center Göttingen, Germany. Results: The overall success rate of applying the RASS for US-guided tip positioning of retrograde-tunneled HDCs was 24/24 (100%), with proper tip position in the right atrium in 18/23 (78.3%), or cavoatrial junction in 5/23 (21.7%) when RASS was positive and improper position when RASS was negative in 1/1 (100%), confirmed by portable anterior-posterior chest radiography, with only minor post-procedural bleeding in 2/24 (8.3%). In addition, this insertion technique allows optimal HDC flow, without any observed malfunction. Conclusion: This is the first study to investigate the efficacy of the RASS for US-guided tip positioning of retrograde-tunneled HDCs in patients with ESKD. Application of the RASS for US-guided tip positioning is an accurate and safe procedure for the proper placement of retrograde-tunneled HDCs.

Semiquantification of Systemic Venous Admixture During Venovenous Extracorporeal Oxygenation Via Bicaval Double-Lumen Cannula in Critically Ill Patients

Venovenous extracorporeal membrane oxygenation (VV-ECMO) is increasingly utilized in acute reversible cases of severe respiratory failure and as a bridge to lung transplantation. Venovenous extracorporeal membrane oxygenation using a bicaval double-lumen cannula (BCDLC) has several advantages over the traditional ECMO configuration; however, it also presents with several unique challenges. The assessment and quantification of venous admixture is difficult due to the specific position of BCDLC within the circulatory system. We describe the nature of the double-lumen bicaval venovenous ECMO cannula and relevant specific issues associated with monitoring complex details of oxygenation within different parts of circulation, including existing barriers for quantification of recirculation and venous admix. New conceptual approach to the quantification of venous admix is described. Right side echocardiographic contrast, when sequentially injected in separate superior vena cava (SVC) and inferior vena cava (IVC) venous basins, bypasses drainage ports of the catheter in double-lumen bicaval VV-ECMO configuration together with deoxygenated returning from the periphery venous blood. It was easily detectable entering right heart chambers by two- and three-dimensional echocardiography. Amount of bubbles from the agitated fluid contrast within right atrium indicates relative amount of venous admixture in relation to the returning from the oxygenator blood which is bubble free.

Agitated saline bubble-enhanced ultrasound for the positioning of cuffed, tunneled dialysis catheters in patients with end-stage renal disease

BACKGROUND

In patients with end-stage renal disease, the use of cuffed, tunneled dialysis catheters for hemodialysis has become integral to treatment plans. Fluoroscopy is a widely accepted method for the insertion and positioning of cuffed dialysis catheters, because it is easy to use, accurate and reliable, and has a relatively low incidence of complications. The purpose of our study was to evaluate the feasibility of tunneled hemodialysis catheter placement without the use of fluoroscopy but with a dynamic ultrasound-imaging-based guided technique.

METHODS

From January 2015 to December 2017, we performed an observational prospective cohort study of 56 patients with end-stage renal disease who required tunneled dialysis catheter placement.

RESULTS

The overall success rate for ultrasound-guided central access was 100%, with a mean number of 1.16 (±0.4) attempts per patient. There were no incidences of guide wire coiling/kinking, carotid puncture, pneumothorax, or catheter malfunction. Catheter flow during dialysis was 286 (±38) mL/min. The total number of catheter days was 7451, with a mean of 133 days and a range of 46-322 days. Life table analysis revealed primary patency rates of 100%, 96%, and 53% at 30, 60, and 120 days, respectively.

CONCLUSION

Dynamic ultrasound-based visualization of microbubbles in the right atrium is a highly accurate method to detect percutaneous implantation of large-lumen, tunneled, central venous catheters without the need for fluoroscopic guidance technology. Future research should further develop and confirm these initial findings.