Two Small Intravenous Catheters for High-Rate Contrast Medium Injection for Computed Tomography in Patients Lacking Superficial Veins to Accommodate a Large Catheter

Abstract

ObjectiveTo prospectively investigate the feasibility of using 2 small intravenous catheters for high-rate computed tomography (CT) contrast injection in patients lacking superficial veins capable of accommodating ≤ 20-gauge catheters.Materials and MethodsSixty-eight consecutive eligible adults referred for dynamic liver CT were enrolled; 58 had previously undergone liver CT, including 8 that experienced extravasation. Two 22- or 24-gauge catheters were placed in all patients after 2–5 venipunctures, and 2 mL/kg of contrast agent (370 mg I/mL) was split-administered through both catheters to achieve total flow rate of 4 mL/s. Patients' experience and examination success rate, defined as uneventful scans completed at 4 mL/s or at < 4 mL/s achieving standard image quality in all phases, were analyzed. Quantitative hepatic signal-to-noise and hepatic vascular contrast-to-noise ratios (CNRs) were compared with 30 control examinations scanned at 4 mL/s using an 18-gauge catheter.ResultsOne case each of extravasation and severe injection pain caused the examination to be aborted. Success rate was 88.2% (60/68; 54 patients scanned at 4 mL/s, 6 at 3.5–3.9 mL/s). Fifty-five of 58 patients (94.8%) that had past CT regarded the venipuncture as more tolerable than (n = 36) or similar to (n = 19) past experiences; 45 of 58 patients (77.6%) found contrast injection less painful than (n = 35) or similar to (n = 10) past experiences. When compared with control examinations, signal-to-noise ratio was similar in all phases (p ≥ 0.502), but the hepatic arterial CNR in arterial phase was slightly inferior (p ≤ 0.047).ConclusionUsing 2 small intravenous catheters can effectively achieve high-rate CT contrast injection in patients lacking adequate superficial veins.

Alternative vascular device for high-flow computed tomography angiography: ultrasound-guided long peripheral catheter (4 Fr × 10 cm)

“…1 Infusion rates between 5 and 8 mL/s have been used and have not been associated with increased extravasation, infiltration, compartment syndrome, necrosis, or limb loss when there is adequate vascular access. [2][3][4] Different sizes of catheters have been evaluated, but wide diameters are required to achieve flows greater than 5 mL/s. Short catheters (20 gauge or higher) are required.…”