Abstract
In Response: McLure and Filshie emphasize that fluoroscopic technique is an important aid in preventing malpositions and in overcoming difficulties during insertion of Hickman catheters. Analyzing their article [1], we found that guidewire kink, sheath introducer kink, and sheath introducer damage ("usually by the under surface of the clavicle") accounted for 44 difficult insertions. These difficulties are attributable to the infraclavicular access (especially from the right side) [2,3], which was used in the study from the Royal Marsden-Hospital (84% right-sided and 15% left-sided subclavian insertions). Cockburn et al. [2] have impressively evidenced that the sharp angle of insertion of the subclavian vein into the superior vena cava is the major cause of kinking (see Figure 1). Furthermore, by using the infraclavicular approach, the rigid sheath and dilator may push against the opposite wall of the superior vena cava, thus impeding catheter feeding. Cockburn et al. therefore preferred a left-sided infraclavicular approach, in which kinking is less likely because of the more obtuse angle [2].Figure 1: A large-bore indwelling catheter placed via the infraclavicular subclavian access. Difficulties during insertion typically occur 1) when passing the gap between the first rib and the clavicle (small arrow) and 2) at the nearly rectangular course from the subclavian vein into the innominate vein (large arrow). At this point, the introducer sheath or the dilator may push against the opposite wall of the superior vena cava. The angular course predisposes to malposition.As outlined in our article [4], this problem was also a crux to our staff in approximately 20% of infraclavicular cannulations, but it was not observed with the right internal jugular and the supraclavicular approach (because the 180[degree sign] curved tunnel, which is obligatory with the internal jugular vein approach, may predispose to obstruction, the supraclavicular approach has become the prefered method in our institution). Recently, we confirmed the superiority of the supraclavicular access to the subclavian/innominate vein for nonangiographic placement of large-bore dialysis catheters (including 109 tunneled devices placed via an introducer sheath) [5]. Avoiding the small gap between the first rib and the clavicle and the impressive anatomically proper coaxial lie of the catheter (Figure 2) enabled easy puncture and feeding of the catheter through the sheath. An internal review of 184 additional soft silicone catheters (83 Hickman catheters and 101 implantable ports) revealed similar results.Figure 2: Anatomically proper coaxial lie of a catheter placed via the supraclavicular access. The arrow indicates the puncture site.The high rate of guidewire malposition reported by McLure and Filshie may also be attributed to the right infraclavicular approach with its angular course. Consistent with previous reports, in a recent review [6] of 2580 percutaneously inserted central venous lines (including 650 tunneled Dacron-cuffed devices), we found the lowest incidence of malposition rate with the supraclavicular route (right and left) (0.96%). This is obviously due to the straight direction into the superior vena cava, which allows deep insertion of the introducer sheath (analogous to the internal jugular vein approach). The highest incidences were found with the left internal jugular and the right infraclavicular access. We disagree with the conclusion that malpositions necessitate catheter reinsertion, with its attendant risks and costs. When postinsertional chest radiographs actually detect malposition, repositioniong without a new puncture is possible by a small cut at the venous entry site. In these rare cases (less than 3%), fluoroscopic aid may be recommended. Our current experience therefore provides evidence that a large number of difficulties is related to the chosen access site and supports the thesis that the implantation of Hickman catheters can be performed without routinely using fluoroscopic guidance, in particular when supraclavicular access is used. Manfred Muhm, MD* Gere Sunder-Plassmann, MD dagger Robert Apsner, MD dagger *Department of Cardiothoracic/Vascular Anesthesia and dagger Acute Dialysis Unit, Internal Medicine III; University of Vienna, Vienna, Austria
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.