Effect of saline flush on enhancement of proximal and distal segments using 320-row coronary CT angiography

Closed versus conventional IV catheter in performing coronary CT Angiography

Background

The purpose of this study was to compare the performance of a closed IV catheter system (CICS) with conventional IV catheters for IV contrast infusion in terms of contrast enhancement and associated complications during coronary CT angiography.

It is a retrospective study of 54 patients for whom a follow-up CCTA was requested were included for this study. Those patients had previous experience with the insertion of a 18 g conventional IV catheter which allows a flow rate of ≥ 6 ml/s and the complications during injection were registered. Patients were informed that a new IV catheter (The BD Nexiva™ Diffusics™ Closed IV Catheter System 22 g while still meeting a high flow rate > 6 m/s) will be used for their examination. We analyzed mean vascular attenuations in the ascending aorta, left main coronary artery, left ventricular (LV) cavity, and descending aorta (DA). Their feedback was collected regarding pain and the number of trials for catheter insertion. In addition, the access site was evaluated for any complication e.g. perforation, contrast extravasation or contamination.

Result

All patients were very satisfied with the new cannula. The catheter was inserted from the first trials. No one has perforation or extravasation. Mean vascular attenuations of the left main coronary artery, LV cavity, and DA were significantly higher during the use 0f the BD Nexiva™ Diffusics™ Closed IV Catheter System (all P ≤ 0.001).

Conclusion

Although the CICS has a small lumen, it allows a high flow rate; therefore, IV access required for CCTA can be secured with higher vascular attenuation and fewer complications. It is encouraged to use the CIVC system for CT angiographic studies, in particular CCTA.

I.v. contrast administration with dual source 128-MDCT: a randomized controlled study comparing 18-gauge nonfenestrated and 20-gauge fenestrated catheters for catheter placement success, infusion rate, image quality, and complications

OBJECTIVE

The purpose of this study was to compare the performance of a 20-gauge fenestrated catheter with an 18-gauge nonfenestrated catheter for i.v. contrast infusion during MDCT.

SUBJECTS AND METHODS

Two hundred five adult outpatients imaged on a dual-source 128-MDCT scanner with arterial phase body CT (flow rates, 5.0-7.5 mL/s) were randomized to either an 18-gauge nonfenestrated or 20-gauge fenestrated catheter. After randomization, any 18-gauge nonfenestrated subjects whose veins were deemed insufficient for that catheter gauge were assigned to a third cohort for placement of a 20-gauge fenestrated catheter. Catheter placement success, infusion rate, contrast volume, maximum pressure, complications, and aortic enhancement levels were recorded.

RESULTS

Catheters were placed on the first attempt in 97% (100/103) for 18-gauge nonfenestrated and 94% (96/102) for 20-gauge fenestrated placements and in two or fewer attempts in 99% of both groups. Mean infusion rates (5.74 mL/s for 18-gauge nonfenestrated and 5.58 mL/s for 20-gauge fenestrated placements) and aortic enhancement levels were not significantly different. Maximum pressure was higher with 20-gauge fenestrated catheters (mean ± SD, 230.5 ± 27.6 pounds per square inch [psi]) than 18-gauge nonfenestrated catheters (mean ± SD 215.6 ± 32.8 psi) (p = 0.002). One subject with an 18-gauge nonfenestrated catheter had a high-pressure alarm. In the third cohort, a 20-gauge fenestrated catheter was successfully placed in two or fewer attempts in 85% (28/33), with one minor extravasation attributed to vein insufficiency.

CONCLUSION

A 20-gauge fenestrated catheter performs similarly to an 18-gauge nonfenestrated catheter with respect to i.v. contrast infusion rates and aortic enhancement levels and can be placed in most subjects whose veins are deemed insufficient for an 18-gauge catheter.