A large catheter sheath introducer with an increased side-port functional gauge

Newly designed catheter introducers manufactured by Arrow International, Inc. or Cook, Inc. have an enlarged sideport hub and an enlarged sheath diameter (from 8.0-8.5 Fr). We measured the in vitro and in vivo infusion pressure-flow characteristics of the side ports of these introducers, with and without 7.0 and 7.5 Fr pulmonary artery (PA) catheters, and expressed these results in terms of an equivalent pressure-flow relationship through standard 22- to 14-gauge peripheral iv catheters. The 8.0 Fr Arrow introducers without a PA catheter exhibited a pressure-flow relationship equivalent to that of the standard 15-gauge catheter, while the 8.0 Fr Arrow introducers with 7.0 or 7.5 Fr PA catheters were equivalent to 18- and 22-gauge standard catheters, respectively. Similarly, the 8.5 Fr Arrow introducers with 7.0 or 7.5 Fr PA catheters functioned like 16- and 19-gauge standard catheters, respectively. Cook introducers had similar flow rates but progressively leaked fluid back through the hemostatic valve when the infusion pressure exceeded 150 mm Hg; consequently, we did not test these introducers in patients. Although in 3 (18%) of 17 patients, the side-port fluid infusion route of the Arrow introducer was grossly obstructed at some unknown point, the side-port enlargements still improved side-port pressure-flow characteristics. It was possible to infuse fluid more rapidly through the introducer side-port while using pulmonary vascular pressure to titrate the infusion rate.