FEATURE

A guided guide to the guide wire

BY KENRICK KAI CHI CHAN AND NAOMI NEAL

The use of guide wires has become a core skill utilised by urologists, especially within the field of endourology. The authors take us through the development of the guide wire and their current use in urology.

The history urethral via the femoral artery In tandem with the development and The first evidence we could find of a “guide into the aorta using a trocar as a guide growing use of the guide wire, progression wire” associated with urology was actually [4]. Seldinger goes onto describe that in the field of ureteroscopy was also published in 1962 by Jalundhwala, in which this concept was further modified by underway. Although the first ureteroscopy a trauma and orthopaedic guide wire (albeit Dr Jonson in 1949 [5] who performed a was accidently performed in 1912 by Hugh a rather thick and stiff wire unlike what thoracic by cannulating the Hampton Young (where he inserted a is used today) broke off during a trans- common carotid artery, and then advanced paediatric cystoscope into an extremely cervical nailing of a femur fracture and then a silver thread to guide the cannula into dilated ureter), it wasn’t until 1960 when the unfortunately migrated into the patient’s the thoracic aorta. Unfortunately, this first flexible ureteroscopy was performed bladder [1]. It was only found three months procedure was abandoned, as it was feared by McGovern and Walzak (almost a after the initial orthopaedic procedure the cannula would damage the aortic decade before the first rigid ureteroscopy). and was removed via a suprapubic wall. However, the described method of Unfortunately, due to the limitations of the cystostomy. However, it is technically the advancing a silver thread to guide and scopes and their relatively poor flexibility, first documented account of a “guide wire” facilitate the introduction of a larger early ureteroscopy was limited to the within the urological system! instrument into a lumen is probably the sole purpose of diagnostics [10]. It wasn’t When one mentions the use of a guide first mention of what would resemble a until the 1980s that a working flexible wire to safely gain access and introduce guide wire today. and rigid ureteroscope was developed. instruments into a lumen or hollow organ, It could be inserted over a guide wire many will know about the Seldinger The move into urology and had the added benefit of supporting technique. Named after the esteemed Dr irrigation apparatus and incorporating a The introduction of the guide wire Sven-Ivar Seldinger, who, before developing working channel through which a variety of was originally used in many vascular his technique, used a piano wire when instruments could be deployed [11]. procedures that benefited from the trying to advance a polyethylene tube for Seldinger technique. Then, in 1962 Pekka [2]. However, Seldinger himself Guide wires today Soila used the Seldinger technique for the did not invent the concept of a guide wire, Today, guide wires are developed for specific transurethral endoscopic introduction of a but rather developed a technique on how specialities and specific situations. Each ureteric catheter into the renal pelvis using to effectively use them. He then went on one is designed and manufactured with a Seldinger guide wire. The purpose of this to manufacture the first modern day guide different characteristics in mind. In fact, procedure was for sampling urine and the wire with the Stille-Werner Company. the basic concepts of guide wire technology injection of radio-opaque contrast, very The main issue that Seldinger and his actually cover 15 broad areas: trackability, much like how today’s retrograde studies colleagues faced was that from torqueability, flexibility, crossability are performed [6]. vessels was a particular problem. This was (ability to navigate past obstructions), In June 1978, Hepperlen et al. described usually secondary to the common use of supportability (ability to support another large bore needles in order to facilitate a novel technique for placing a ureteric device over it), core diameter, core taper, tip the placement of large bore . over a Teflon guide wire which had style, shaping ribbons, tip coils, coatings, The catheters themselves were also very to be inserted into the renal pelvis via support, tip load, support catheters, and flexible, meaning that it was difficult to an endoscope first [7]. Six months later, wire length [12]. advance them once they were in the lumen Bigongiari described the transurethral It is also not only the characteristics of as they would kink or bend. Seldinger was conversion of a percutaneous ureteric the wires that vary, but also the materials able to overcome this problem by using a stent to an indwelling pigtail stent using from which they are made from. Nitinol ‘metal leader’ which was a metal wire with a guide wire [8]. Shortly after this, in (nickel-titanium alloy) or steel is usually the a flexible tip. 1981, Fritzsche et al. first described the main core in most wires. Some guide wires In his publication ‘Catheter replacement successful transvesical bypassing of ureteric are coated with other substances such as of the needle in percutaneous arteriography, obstructions using angiographic guide silicone or polytetrafluoroethylene (PTFE) a new technique’ [3], Seldinger refers to wires and catheters in combination with which enhance lubricity, or with other novel previous papers published around the endoscopy [9]. These procedures formed the hydrophilic coatings to allow for easier subject of introducing catheters into basis of today’s practice and have become manoeuvrability in tortuous lumens [13]. lumens. This included Pedro L Fariñas’s more efficacious with the advancements in The field of guide wire technology and described method in 1941 of passing a guide wire technology. the birth of endourology have encouraged

urology news | MAY/JUNE 2020 | VOL 24 NO 4 | www.urologynews.uk.com FEATURE

research into guide wire characteristics, more flexible hydrophilic-tipped wires. 5. Jonsson G. Thoracic aortography by means of a cannula inserted percutaneously into the common carotid and there are now publications on the Changing an old encrusted ureteric stent artery. Acta radiol 1949;31(5-6):376-86. analysis of guide wire characteristics and would be a good example of this. When the 6. Soila P. Guide wire replacement in catheterization of their clinical use in everyday practice. They lumen of the stent is encrusted, the stiffness ureters. J Urol 1962;87(6):1000-2. have facilitated an explosion of progress of a starter wire is a much better tool to push 7. Bigongiari LR. Transurethral conversion of a within the field of endourology and are through the encrustations than the more percutaneous ureteral stent to an indwelling stent. Am J Roentgenol 1978;131(6):1098-9. flexible hydrophilic-ended wires. used in a diverse number of urological 8. Hepperlen TW, et al. Self-retained internal ureteral procedures and clinical situations including We should also not forget the important : A new approach. J Urol 1978;119(6):731-4. ureteroscopy, stent insertions, percutaneous use of the guide wire by some of our 9. Fritzsche P, et al. Urologic applications of angiographic nephrolithotomy (PCNL) access, facilitating colleagues, the interventional radiologists guide wire and catheter techniques. J Urol 1981;125(6):774-80. dilation of urethral and uretero-ileal who are able to use a multitude of 10. Bagley DH, Huffman Jl, Lyon ES. Combined rigid and anastomotic strictures, and even the different guide wires for the placement of flexible ureteropyeloscopy.J Urol 1983;130(2):243-4. placement of difficult urethral catheters. nephrostomies and antegrade stents when 11. Bagley DH. ‘Development of the Ureteroscope’. In: an endoscopically retrograde approach Patel SR, Moran ME, Nakada SY (Eds.). The History is just not feasible, or even for renal of Technologic Advancements in Urology Springer Which guide wire to use International Publishing; 2018. So how do you choose which wire to use embolisation, thereby giving our patients an 12. Fornell D. Understanding the design and function of in which situation? Each clinician will additional option of treatment, especially in guidewire technology. Diagnostic and Interventional undoubtedly have their own preferences those in whom a general anaesthetic may Cardiology 2016 www.dicardiology.com/article/ not be suitable. understanding-design-and-function-guidewire- based on their personal experience and technology [accessed 9 December 2019]. expertise. Some very valuable advice given A wide range of wires are used in 13. Hernandez Bustos N, Yaghoubian A, Mozafarpour S, to me as a trainee in urology was to not only interventional with varying tips Eisner B. ‘History of the Development of Guidewires, have a plan A, but also a plan B, C, D and E! and flexibilities. These include the ultra-stiff Access Sheaths, Baskets, and Ureteral Stents’. In: Patel SR, Moran ME, Nakada SY (Eds.). The History of Technologic wire that is used in nephrostomy insertion An example of this might be when trying to Advancements in Urology Springer International navigate an impacted ureteric stone in the after initial puncture of the kidney. This Publishing; 2018. middle of the night. One may wish to start allows for the loading of a robust dilator with a standard starter wire, it has a slightly that is used to dilate the nephrostomy tract stiffened tip, and doesn’t cost as much as prior to nephrostomy tube insertion. In the some of the other more specialised wires. same way, the super stiff wire is also used in If this fails to get past the stone, one could PCNL operations and suprapubic catheter try plan B, perhaps a Sensor wire, which insertions in order to load the dilator as well has a hydrophilic tip that allows it to better as the working sheath. navigate around stones (under fluoroscopic Hydrophilic wires are also commonly screening) when the ureter is tight. used by interventional radiologists for the Failing that, plan C might be to use a more insertion of antegrade ureteric stents via AUTHORS specialised (and more costly) completely nephrostomies. For example, a patient hydrophilic wire. These can be quite tricky who has an obstructed kidney after a to use given how they are designed to slip transurethral resection of a bladder tumour past obstructions, as well as slip through the would likely have a nephrostomy inserted in surgeon’s fingers! (Sometimes, using a piece the first instance. After which, an antegrade of gauze to manipulate the wire helps). So, stent might be considered, however, given what if this also fails? Another technique the possibility of a narrowed ureteric orifice that is commonly used is to pass a wire up and recent bladder resection resulting in to the obstruction, then pass a ureteric friable and possibly thin bladder wall, the extremely flexible hydrophilic wires are a catheter over the wire up to the stone. With Kenrick Kai Chi Chan, the added rigidity of the ureteric catheter good option to both navigate the ureteric orifice as well as be less likely to traumatise Core Surgical Trainee, Urology Department, Churchill stabilising the ureter, a hydrophilic wire can Hospital, Oxford University Hospitals NHS Foundation then be tried to navigate around the stone. the surrounding bladder wall. Trust. Similarly, such a technique can be employed Guide wires have come a long way since to straighten a tortuous ureter when placing the first silver thread and piano wire. The a stent. By advancing the catheter up to the need for advancements in this area has tortuosity and manipulating the guidewire produced an arsenal of tools from which proximally through each tortuosity, an urologists (and other specialities) can choose excess of coiled guidewire (often a super from, each designed and manufactured for stiff wire is helpful here) can be placed different clinical purposes. in the renal pelvis. The ureter can then be straightened whilst simultaneously References retracting the wire from the renal pelvis and 1. Jalundhwala JM. An unusual foreign body (guide wire) in bladder. BJUI 1962;34(3):335-7. advancing the ureteric catheter proximally 2. Nyman U. Seldinger Biography. 2000 www.seldinger. Naomi Neal, up the ureter. se/gallery/seldinger%20biography.pdf [accessed 5 Urology Consultant, Urology Department, Churchill Apart from cost, why would you want December 2019]. Hospital, Oxford University Hospitals NHS Foundation to use a stiff starter wire in endourology? 3. Seldinger SI. Catheter replacement of the needle in Trust. Surely one would want to be as least percutaneous arteriography: A new technique. Acta Radiologica [old series] 1953;39:(5):368-76. traumatic as possible? There are some Declaration of competing interests: None declared. 4. Fariñas PL. A new technique for the arteriographic situations where it’s much easier to use a examination of the abdominal aorta and its branches. stiffer-ended starter wire rather than the Am J Roentgenol 1941;46:641.

urology news | MAY/JUNE 2020 | VOL 24 NO 4 | www.urologynews.uk.com