Kidney stones are a prevalent global disease, with varying prevalence rates across different regions. The prevalence in North America ranges from 7–13%, in Europe from 5–9%, and in Asia from 1–5%[3]. In China, the prevalence is approximately 5.8%[4]. Among kidney stone patients, approximately 10–20% present with staghorn kidney stones[5]. PCNL is the primary treatment approach for staghorn kidney stones[1]. Due to the branching and anatomical characteristics of staghorn kidney stones, multi-tracts and stages surgical treatments are often required to improve the stone-free rate(SFR). Research indicates that the higher of the S.T.O.N.E score for the staghorn stone, the more stone branches there are, and the greater the likelihood of multi-tract and muti-stages PCNL, which can lead to a reduced SFR and longer postoperative hospital stay[6, 7]. Aron et al. reported that an average of 3.28 percutaneous renal channels were needed to effectively remove staghorn kidney stones, achieving a SFR of 84%[8]. However, the use of multiple renal accesses also heightens the risk of surgical bleeding[9, 10]. Consequently, the routine placement of indwelling nephrostomy tubes following complex PCNL is performed to mitigate postoperative bleeding risk, despite the associated increase in postoperative pain and length of hospital stay.
Compared to patients with indwelling nephrostomy tubes, Tubeless PCNL allows for earlier resumption of normal activities, reduced postoperative pain, and shorter hospital stays[11]. Although studies have demonstrated the safety of tubeless PCNL in patients without complications such as bleeding[12], not all PCNL patients are suitable candidates for this approach. Currently, tubeless PCNL is commonly recommended for uncomplicated cases with small stones, short operative duration, and complete stone clearance[13, 14]. However, for patients with high-risk factors like staghorn kidney stones and increased bleeding risk, urologists typically opt for the conventional method involving postoperative indwelling nephrostomy tubes[15].
Scholars have made various attempts to expand the indications for tubeless PCNL and reduce tract bleeding. Lee et al. explored the use of fibrin glue injection for hemostasis[16], while Takeda M employed electrocoagulation with a resectoscope to mitigate the risk of postoperative bleeding[17]. Joel E employed compression with an adjunct hemostatic agent for tract closure[18]. In our study, we also implemented tubeless PCNL for complex stones and utilized a microchannel hemostatic electrocoagulation device during the procedure to address tract bleeding and minimize postoperative complications. Our initial results were promising. The microchannel hemostatic electrocoagulation device comprises three components: a power supply, a handle, and an electrode(Fig. 4). The detachable electrode, approximately 40 cm in length and made of medical stainless steel, can be inserted through the nephroscope and connected to the handle. The larger electrode head enhances contact surface area, thereby improving hemostatic efficacy. After confirming complete stone fragmentation, a safety guidewire is inserted through the channel, and the percutaneous renal sheath is gradually withdrawn while monitoring the tract. If bleeding is observed at the percutaneous access site, the microchannel hemostatic electrocoagulation device is inserted for direct visual electrocoagulation to achieve hemostasis. Postoperative nephrostomy tube placement is unnecessary, and postoperative review CT scans reveal no complications such as perirenal effusion, thereby effectively reducing postoperative pain and hospital stays while ensuring safety.
Scholars have explored various surgical approaches to improve SFR, minimize percutaneous renal puncture access, and reduce surgical complications. The combination of PCNL and F-URS has gained popularity in the management of kidney stones, facilitated by advancements in surgical equipment, particularly flexible ureteroscopes. This approach proves beneficial for managing staghorn kidney stones as it improves SFR, reduces complications, and minimizes the need for additional percutaneous accesses and procedures[19, 20]. Following the initial removal of the majority of stones via PCNL, some stones within the parallel calyces may remain inaccessible through existing channels. Utilizing a flexible ureteroscope, these stones can be fragmented with a holmium laser and then removed or relocated to the renal pelvis for subsequent fragmentation and the removal. This obviates the requirement for additional percutaneous access tracts. Unlike the conventional retrograde approach, we employ antegrade percutaneous F-URS through the existing percutaneous access tract. We utilize a disposable flexible ureteroscope, facilitating smooth access to all parallel calyces. Furthermore, the 18Fr percutaneous renal sheath offers a larger and shorter route compared to the 12/14 Fr ureteral access sheath, simplifying the operation of the flexible ureteroscope and enabling direct removal of larger stones. Additionally, the combination of flexible ureteroscope, percutaneous nephroscope, and ultrasound can be utilized to confirm the absence of residual stones at the end of lithotripsy.
Following the completion of stone removal, all patients underwent combined flexible ureteroscopy, percutaneous nephroscopy, and ultrasound to complete stone clearance. Electrocoagulation was subsequently performed on the percutaneous renal tract to achieve hemostasis, eliminating the need for nephrostomy tube placement. None of the patients experienced symptoms such as fever, bleeding, or back pain, and the first postoperative day CT scan revealed no residual stones. Subsequent urological CT scans performed one month after surgery showed no perirenal effusion or other complications. Additionally, the double-J stent was successfully removed during this follow-up period.