Original Article
Transradial approach for challenging vascular access interventions
Vascular 2015, Vol. 23(4) 374–381 ! The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/1708538114546882 vas.sagepub.com
Mitra Rahmatzadeh1, Vikram Vijayan1, Carsten J Ritter1, Joseph Hockley1, Benjamin DK Leong1, Monique Sandford1,2 and Bibombe P Mwipatayi1,2,3
Abstract Background: Percutaneous interventional procedures for vascular access are usually performed using the draining cephalic or basilic vein. The transradial approach, which has been extensively investigated for coronary angiography and intervention, could be an attractive new technique for peri-anastomotic arteriovenous fistula stenosis. Method: From June 2012 to February 2013, 30 patients with end-stage renal failure were evaluated for transradial vascular access intervention. A 4-French (Fr) micropuncture kit was used to access the radial artery and then subsequently upgraded to a 5-Fr sheath. Fourteen patients required an upgrade to a 6-Fr sheath for the final intervention. Results: Primary technical success (residual stenosis 50% compared to the adjunct vein in the fistula. Abnormal fistula function was defined by clinical indicators such as recurrent clotting in needles, difficult needle placement, increased bleeding times post needle removal, swelling in limbs with vascular access and reduced dialysis adequacy (Kt/ V < 1.2 or URR < 65%) as well as by a number of dialysis parameters such as access flow (15%), reduced blood flow rate, venous pressure >120 mmHg with a 15-gauge needle at 200–225 ml/min blood flow and negative arterial pressure. URR stands for urea reduction ratio, meaning the reduction in urea as a result of adequate dialysis. On average, a Kt/V of 1.2 is roughly equivalent to an URR of about 63%, where K stands for the dialyzer clearance (the rate at which blood passes through the dialyzer), expressed in millilitres per minute (ml/min); t stands for time and V, the bottom part of the fraction, is the volume of water a patient’s body contains.
Interventional procedure Multiple operators participated in this single institutional study. The study design and approach were clearly defined in our practice guidelines enabling the delivery of a standardised procedure each time. Radial artery access was obtained at the wrist, 1–2 cm proximal to the styloid process. However, an Allen’s test was used to assess the integrity of the radial artery to perfuse the palmar arch. If the Allen’s test was negative, the hand was reliant on the radial artery for perfusion and an alternative site of access was used. After superficial infiltration of local anaesthesia, the radial artery (left side, n ¼ 18; right side, n ¼ 12) was punctured under ultrasound guidance using a 21-gauge, 4-cm Echo TipÕ needle (Cook Medical Incorporation, Bloomington, IN). A short 4- to 6- Fr introducer sheath (Terumo, Tokyo, Japan) was inserted (Figure 1). A 4-Fr glide catheter was used to direct either a hydrophilic 0.03500 angle GuidewireÕ (Terumo Medical Corporation, Somerset, NJ) or a V-18TM Control WireTM (Boston Scientific, Miami, FL) into the target brachial artery beyond the fistula anastomosis. Three to five thousand international units of heparin were administered intra-arterially. A diagnostic angiogram was performed with the catheter located at least 2–3 cm beyond the fistula anastomosis in order to accurately assess the anatomy. This enabled visualisation of the arterial tree at least 5–6 cm proximal to the site of insertion, including the visualisation and appropriate management of any potential central venous lesions. The endovascular intervention on any lesion within the fistula was then performed as required.
Definition and study end-point Primary outcome measures were post-interventional primary AVF patency and post-interventional primary assisted AVF patency, as defined by Sidawy et al.5 Patients were censored at the time of death, clinically dialysis-related issue, clinically significant stenosis, AVF ligation, transplantation or peritoneal dialysis conversion. A stenosis of the juxta-anastomotic artery has been defined as either luminal narrowing equal to or exceeding 50% compared to the normal vascular segment, located adjacent to the stenosis,6,7 or a minimal luminal diameter of 2.7 mm of the venous segment of the outflow of the fistula.8 Patients with radial artery diameters at the level of the wrist