V11-09: The parallel guidewire rapid release percutaneous tract dilation
The parallel rapid release ureteral access sheath is a good way to transform the working wire into a safety wire. The guide is passed in the first 4 cm of the dilator which has a lateral slit. When the dilator is retrieved, the wire is released from the dilator through the lateral slit, and stays outside the access sheath. _x000D_ We present a video of percutaneous tract dilation parallel to the guidewire, using the same principle. The working guidewire becomes safety guidewire outside the Amplatz sheath, at the end of the dilation.
Between February 2016 and October 2016, 15 PCNL have been performed with dilation of the tract beside the guidewire._x000D_ Technique: A stiff 8 Fr ureteral catheter or JJ-stent pusher is used. The Amplatz catheter can also be used. Its tip is held with a forceps. With a &[Prime]lancet&[Prime] blade scalpel, beginning from the tip, a 4-5 cm longitudinal slit is performed in one side of the catheter. At the end of the slit, the scalpel is turned on its self to perform a small hole to accommodate the guidewire. It will be the egress point of the guidewire. After calyx puncture, a guidewire is inserted down the ureter or it is coiled in an opposite calyx. A pre-dilation to 12 Fr is performed. The catheter is bent just after the slit. Thus, the small hole will be in the apex of the bend. The tail of the guidewire is inserted into the slit tip of the catheter. After transiting in the 4 cm of the catheter with the slit, the guidewire will egress through the hole, in the summit of the bend. The catheter is advanced over the guidewire until reaching the calyceal cavity. &[Prime]One shot&[Prime] dilation is performed over the catheter with a 24 Fr Amplatz dilator and sheath. The long part of the catheter, Amplatz dilator and sheath are beside the working guidewire. When the Amplatz sheath reaches the calyx, the catheter is attracted and the guidwire is released from the first part of the catheter through the slit. Thus, the working guidewire become safety guidewire outside the Amplatz sheath._x000D_
15 patients had PCNL with dilation with this technique, 9 males and 6 females. The mean age was 39 (56-23). 8 right kidneys and 7 left. The main stone burden was 43 mm (32-56). The dilation beside the guidewire was possible in all cases. Operative time was 70 min (45-95). The tract dilation time was 4.5 min (3.5- 7). The hemoglobin drop was 0.89 (0.5-1.8). There was no complication noted during this dilation.
The dilation beside the guidewire is safe and feasible in this small series. It allows the economy of a guidewire. However, the catheter has to be very stiff to allow having a straight path to guide the dilator into the calyx. More studies are necessary to develop the technique.