Tubeless simultaneous bilateral percutaneous nephrolithotomy: Safety, feasibility and efficacy in an Indian setting

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1 bs_bs_banner International Journal of Urology (2014) 21, doi: /iju Original Article: Clinical Investigation Tubeless simultaneous bilateral percutaneous nephrolithotomy: Safety, feasibility and efficacy in an Indian setting Sunil Pillai, Dilip Mishra, Pritam Sharma, Giridhar Venkatesh, Arun Chawla, Padmaraj Hegde and Joseph Thomas Department of Urology, Kasturba Medical College and Hospital, Manipal University, Manipal, Karnataka, India Abbreviations & Acronyms AKI = acute kidney injury CSRF = clinically significant residual fragments HD = hemodialysis ICD = intercostal drainage ICS = intercostal space INR = Indian rupees PCNL = percutaneous nephrolithotomy SBPCNL = simultaneous bilateral percutaneous nephrolithotomy SWL = shock wave lithotripsy Correspondence: Dilip Mishra M.S., M.R.C.S., M.Ch., Department of Urology, Kasturba Medical College, Manipal University, Manipal, Karnataka , India. docdilipmishra@yahoo.co.in Received 28 June 2013; accepted 23 October Online publication 28 November 2013 Objectives: To study the safety, feasibility and efficacy of tubeless simultaneous bilateral percutaneous nephrolithotomy. Methods: We retrospectively studied 85 patients who underwent tubeless simultaneous bilateral percutaneous nephrolithotomy in the Department of Urology, Kasturba Medical College, Manipal, Karnataka, India, from July 2006 to June The demographic profile and outcomes were compared with the other existing series reported in the literature. Results: A total of 65 male and 20 female patients with a mean age of 45.7 ± 11.6 years underwent tubeless simultaneous bilateral percutaneous nephrolithotomy. The mean stone burden was 299 mm 2, with 12 staghorn calculi. Mean operative time was 87.6 ± 35.5 min. A total of 95% of stones were cleared with single access tracts. The success rate of tubeless simultaneous bilateral percutaneous nephrolithotomy (stone clearance) was 95.2%. Mean hemoglobin drop was 1.1 ± 0.9 gm% per patient, with 10.5% of patients requiring blood transfusion. Mean hospital stay was 69.6 ± 28.4 h. Complications included urosepsis (Clavien grade 4), acute kidney injury requiring hemodialysis (grade 3), pneumonia (grade = 2) and hydrothorax requiring intercostal drainage tube insertion (grade 3). On follow up, 4.7% of the renal units required ancillary procedures. Conclusions: Our findings confirm that tubeless simultaneous bilateral percutaneous nephrolithotomy is a safe and effective modality of treatment. It allows obviating a second anesthetic exposure, thus reducing analgesic requirement, hospitalization time and costs. This translates into a significant socioeconomic impact on the outlook of Indian patients presenting with bilateral renal stone disease. Key words: tubeless. Introduction bilateral, cost-effective, percutaneous nephrolithotomy, simultaneous, Much has changed since the first PCNL was carried out by Fernstrom and Johannson in 1976, almost four decades ago, when it was carried out as a staged procedure. 1 It was 8 years later that Wickham described his series of single stage PCNL in 1984, with a mandatory nephrostomy tube drain post operatively. 2 The nephrostomy tube was believed to tamponade bleeding, help in drainage of the pelvi-calyceal system, minimize urinary extravasation and provide access for second look procedures if required. Bellman first described the technique of tubeless PCNL in Since then, the practice of routine tubeless PCNL has been increasingly accepted for large, uncomplicated renal calculi. 4,5 In the past decade, it has been extended to tubeless SBPCNL when it was first carried out by Weld and Wake in Tubeless SBPCNL allows faster convalescence with less postoperative pain, offering equal efficacy to stone clearance, in addition to obviating a second anesthetic exposure Currently, totally tubeless PCNL is also carried out, but in more selected cases Only a limited number of studies are available on tubeless SBPCNL In the Department of Urology, Kasturba Medical College, Manipal, Karnataka, India, we treat a large volume of patients with renal stones. A large number of these comprise of patients having bilateral renal calculi. The present study was initiated to evaluate the safety, feasibility and cost-effectiveness of tubeless SBPCNL in treatment of bilateral renal stone disease. To our knowledge, this represents the largest series of such cases published in the literature. Methods This was a retrospective descriptive study of patients undergoing tubeless SBPCNL from July 2006 to June 2013 in our institution. During the study period, a total of 4267 PCNL were carried 2013 The Japanese Urological Association 497

2 S PILLAI ET AL. Fig. 1 Computed tomography scan images showing bilateral renal stones. Fig. 2 Postoperative picture showing bilateral skin incision at Amplatz insertion site with skin suture. out. The procedures were carried out by three senior urological surgeons in our department. The choice of PCNL, as opposed to shock wave lithotripsy or retrograde intrarenal surgery was made after detailed counseling of the patients. It is important to mention that most of our patients reach our tertiary center either by referral or on their own volition to undergo PCNL in order to attain complete/maximal stone clearance in a single/minimum number of procedures. This is largely because of the logistics of travel from rural/suburban areas, and the financial burden of repeated procedures and regular follow up. Exclusion criteria included staged procedures and pediatric patients. Patients enrolled in the study were counseled and consented, understanding that tubeless SBPCNL would be considered only after the successful and uneventful completion of the first side. Preoperative work-up included complete blood picture, renal function tests, serum calcium and uric acid, and non-contrast computed tomography (Fig. 1). All surgeries were carried out by senior consultants. It was the same team that did both the sides, one after the other. All procedures were carried out under general anesthesia. Bilateral 6-Fr ureteral catheter placement was carried out before turning the patient in the prone position. Both sides were painted and draped separately. Access to the pelvi-calyceal system was carried out by the urologist in all cases. Punctures were made under fluoroscopic guidance, and Alken s telescopic metal dilators were used in all cases. Depending on the stone burden and infundibular width, and 26-Fr nephroscopes, and Amplatz sheaths of size Fr were used. Stones were either removed intact or fragmented using a pneumatic lithoclast. No nephrostomy tube was placed. On completion, stone clearance was confirmed with a combination of meticulous nephroscopy and fluoroscopy. A ureteral stent was inserted antegradely. No tract sealant was used, and the incision site was closed with a silk suture (Fig. 2). Local anesthetic infiltration with 2% lignocaine was given into the tract site in all cases. Operative time was calculated from the time of making the puncture to the time of placement of skin suture. On successful and uneventful completion of the first side, the same procedure was carried out for the other kidney. Postoperatively, complete blood picture and renal function tests were repeated; abdominal ultrasonography and abdominal roentgenogram (Fig. 3) were carried out postoperatively to assess the presence of any CSRF. Perioperative complications were stratified into five grades according to the modified Clavien classification system. 15 Grade 1 defined all events that, if left untreated, would have a spontaneous resolution or required a simple bedside intervention. Grade 2 complications required specific medication, including antibiotics and blood transfusion. Grade 3 complications necessitated surgical, endoscopic or radiological intervention (3a without general anesthesia, 3b under general anesthesia). Neighboring organ injuries and organ failures were classified as grade 4, and death was considered a grade 5 complication. Patients were asked to follow up after 3 4 weeks for double J stent removal. At the same time, an abdominal X-ray was obtained to look for any CSRF. The values are presented as the mean ± standard deviation. Data were analyzed using SPSS 16 for Windows (SPSS, Chicago, IL, USA). The cost of tubeless SBPCNL was analyzed in the group, and was compared with a consecutive group of 60 patients who underwent unilateral tubeless PCNL within the same study period. The average cost of an uncomplicated The Japanese Urological Association

3 Tubeless SBPCNL Fig. 3 Postoperative X-ray of the abdomen showing bilateral double J stents in situ after complete stone clearance. Table 1 Demographic variables Table 2 Operative and postoperative outcomes Total patients 85 Total renal units 170 Male/female 65/20 Age in years (mean ± SD), 45.7 ± 11.6 (range 18 79) Mean stone burden 299 ± 310 mm 2 (range mm 2 ) unilateral PCNL was calculated and compared with the average cost of an uncomplicated tubeless SBPCNL. Results Tubeless SBPCNL was carried out in 85 patients (170 renal units) 65 men and 20 women. The mean age was 45.7 ± 11.6 years (range years). The mean stone burden was 299 ± 310 mm 2 (range mm 2 ; Table 1). There were 12 staghorn calculi (mean burden 1256 mm 2 ) in the study. The mean operative time was 87.6 ± 35.5 min (range min). The mean operative time per renal unit was 44.5 ± min (range min). Single punctures were used to gain access in 95% of patients (163/170 renal units). Out of the single punctures, 118 were inferior calyceal (69.4%), 25 midcalyceal (14.7%) and 20 were superior calyceal (11.7%). Two punctures were required in seven (4.1%) renal units. A total of 14 punctures were supracostal, with five in the 10th to 11th ICS and nine in 11th 12th ICS. Totally tubeless PCNL was carried out in 21 renal units (21.3%), and even a double J stent was not inserted after stone clearance. Parenteral analgesia was required in most patients within the first 18 h, and intravenous or intramuscular Pentazocine 50 mg was used. The mean hospital stay was 69.6 ± 28.4 h (range days). The mean drop in hemoglobin was 1.1 ± 0.9 g% (range g%). Postoperative complications were graded according to the Clavien grading system. 15 Blood transfusion was given to nine patients (10.5%) postoperatively (Clavien grade 2). Three patients (3.5%) had hydrothorax requiring ICD insertion (Clavien grade 3), one patient (1.1%) developed pneumonia (Clavien grade 2), one patient (1.1%) developed urosepsis (Clavien grade 4) and one patient (1.1%) developed acute kidney injury (AKI) requiring HD (Clavien grade 3; Table 2). The success rate of tubeless SBPCNL (stone clearance) was 95.2%. On follow up, eight renal units (4.7%) had CSRF four requiring PCNL and four requiring ureteroscopy. Mean operative time 87.6 ± 35.5 min (range min) Mean operative time per renal unit 44.5 ± min (range min) No. punctures One 163/170 renal units Two 7/170 renal units Single punctures distribution Inferior calyx 118 Middle calyx 25 Superior calyx 20 Mean hospital stay 69.6 ± 28.4 h (range days) Mean drop in hemoglobin 1.1 ± 0.9 g% (range g%) Postoperative complications Blood transfusion (Clavien grade 2) 9 (10.5%) Pneumonia (Clavien grade 2) 1 (1.1%) Hydrothorax requiring ICD insertion 3 (3.5%) (Clavien grade 3) AKI requiring HD (Clavien grade 3) 1 (1.1%) Urosepsis (Clavien grade 4) 1 (1.1%) Complete stone clearance 162 renal units (95.2%) CSRF requiring ancillary procedure 8 renal units (4.7%) Totally tubeless PCNL (no DJ Stent) 21 renal units (21.3%) The average cost of an uncomplicated tubeless SBPCNL procedure in our institute was INR (US$750), whereas the average cost of an uncomplicated unilateral PCNL amounted to INR (US$583). If a patient was to undergo staged PCNL for bilateral renal stones, they would incur an extra cost of INR (US$416) as compared with a patient undergoing tubeless SBPCNL. Discussion PCNL has evolved and has been accepted as a standard procedure for large (>2 cm) renal calculi. The recent European Association of Urology guidelines recommend PCNL as the procedure of choice for stones >2 cm. 16 Several improvements in the technique and equipment of PCNL have led to decreased morbidity. Tubeless PCNL is a significant step in this direction. 3 5 The basis for this concept is a surgical principle that assumes that the nephrostomy tract, which represents a form of controlled trauma to the urinary tract, will heal spontaneously, provided adequate drainage is secured. 12,13 Several studies have shown 2013 The Japanese Urological Association 499

4 S PILLAI ET AL. Table 3 Comparison with other studies Study n Stone burden Operative variations Duration (min) Mean hospital stay (h) Analgesic requirement Complications Weld and Wake 6 Tracts balloon dilated to 30-Fr N/A N/A Tracts dilated to 30-Fr N/A N/A 1 Right: 225 mm 2 ; Left: mm 2 34-Fr Amplatz sheaths Wound closed with 0 chromic sutures Gupta et al. 7 1 Right: 84 mm 2 ; Left: 108 mm 2 30/34-Fr Amplatz sheaths Stones fragmented with pneumatic lithotripter Istanbulluoglu et al mm 2 7-Fr ureteral catheters were placed bilaterally Tenoxicam 1 patient had postoperative Tracts dilated with Amplatz dilators 20 mg anuria treated with bilateral indwelling ureteral stents at 26-Fr rigid nephroscope postoperative hour 16 Stones fragmented with pneumatic lithotripter No antegrade stents inserted post PCNL Shah et al Right: mm 2 ; Left: Tract dilated with telescoping metal dilators Morphine mm 2 Stones fragmented with pneumatic lithotripter 16.6 mg Wound was strapped with a pressure dressing Alice Yu et al Case 1: 121 to 225 mm 2 ; Case 2: Right: 2500 mm 2 ; Left: 841 mm 2 Tracts balloon dilated to 30-Fr Diclofenac mg Stones fragmented using combined pneumatic and ultrasonic lithotripter with rigid nephroscope and Holmium laser with flexible nephroscope 6F stents inserted 4 patients presented with post-pcnl residual stone fragments; one required SWL 1 patient presented with stone recurrence 2 months post-pcnl, treated with ureteroscopy and holmium laser lithotripsy Wang et al mm 2 Tracts dilated using Amplatz dilators patients required postoperative SWL Stones fragmented with pneumatic lithotripter Percutaneous tract cauterized using roller ball resectoscope for haemostasis 7-Fr stents inserted Wound closed with 3-0 Nylon sutures Present study mm 2 Tracts dilated using Amplatz dilators Pentazocine 50 mg Stones were fragmented with pneumatic lithotripter Wound closed with 1-0 Silk sutures 3 with pleural effusion, 1 patient pneumonia and 1 patient urosepsis. follow up, 8 renal units had CSRF requiring ancillary procedures The Japanese Urological Association

5 Tubeless SBPCNL the nephrostomy tube to not only be unnecessary in the majority of cases, but in fact, increases the morbidity by increasing postoperative pain and analgesic requirement, increases risk of urinary leak and prolonging hospital stay. 3 5 The management of bilateral renal calculi safely remains a challenge. The usual approach has been to undergo PCNL in a staged manner. Silverstein et al. reported a first large comparison of SBPCNL with staged bilateral PCNL. 17 They showed similar stone-free rates, blood loss per operation, and transfusion rates for simultaneous and staged bilateral PCNL. They showed that reduced total operative time, hospital stay and total blood loss, along with the requirement for only one anesthesia, makes SBPCNL an attractive option for select individuals. However, in patients with larger, less easily accessible stones, excessive bleeding might be encountered more frequently on the first side, thereby delaying management of the second side to a later date. 17 Wang et al. compared staged PCNL for bilateral renal stones versus tubeless SBPCNL in a randomized controlled trial. 9 They noted that the length of stay in the tubeless SBPCNL group (3.62 ± 1.03 days) was shorter than in the staged tubeless PCNL group (6.37 ± 1.55 days) to a statistically significant degree. Similarly, the pain score and analgesic requirements favored the tubeless SBPCNL group with statistical significance. Return to work and direct costs were nearly uniformly higher for patients undergoing the staged tubeless PCNL compared with those undergoing simultaneous bilateral tubeless PCNL. The tubeless SBPCNL group also showed shorter operative times and shorter hospital stay. 9 SBPCNL has been shown in a few studies to date to be a safe and efficacious treatment option It has the advantages of a single anesthesia, single surgical and psychological stress, reduced total operating time, less medication, and shorter hospital stay, with the obvious cost implications. 9 The tubeless PCNL technique reduces patient discomfort, considerably reducing the analgesic requirement, and thereby hastens convalescence and further shortens hospital stay. 3 5 In an appropriately selected group of patients, tubeless SBPCNL attempts to combine the best of both these advancements in treatment of renal calculi for benefit of the patient. To date, six studies have analyzed SBPCNL. 6 10,14 Our results compare favorably with the existing studies. To our knowledge, the present study represents the largest single-center series in the available literature. The present results compare favorably with the existing studies. 6 10,14 Three case reports, including a single patient 6,7 and two patients, 10 have shown successful tubeless SBPCNL with comparable results. Istanbulluoglu et al. reported six cases of tubeless SBPCNL. 14 The stone burden was mm 2. The duration of the procedure was 87.5 min, with a mean hospital stay of 43.2 h. One patient developed postoperative anuria managed with bilateral ureteral stenting at 16 h postoperatively. Shah et al. reported 10 cases with a stone burden of mm 2. 8 The duration of the procedure was 90.1 min, with a mean hospital stay of 40.2 h. Four patients presented with post-pcnl residual stone fragments, of which one required SWL. Wang et al. reported the largest series of 50 cases of tubeless SBPCNL compared with staged PCNL in 49 cases. 9 The mean stone burden was mm 2. They described cauterization of the percutaneous tract using a roller ball for hemostasis. The average duration of procedure was min, with a mean hospital stay of 38.7 h. However, the mean stone clearance was 72%, and nine patients required SWL during follow up. In the present study, 85 patients were operated on. The decision to proceed to the second side was taken after successful completion of the first side, and in conjunction with the anesthetist. Our mean stone burden was 299 mm 2. We have used internal DJ stents (6-Fr) in all but 21 renal units, which were totally tubeless. The mean operative time, mean duration of the procedure and mean hospital stay were comparable with other studies (Table 3). We achieved 95.2% complete stone clearance, which is comparable. Though the mean hemoglobin drop was 1.1 g%, a blood transfusion was required in 10.5% of patients, which was an incidental finding. The rate of blood transfusion after bilateral simultaneous PCNL varied in the literature from 4.2 to 28.6%. 17,21,22 We observed that the amount of blood loss and the subsequent need for transfusion correlated with the number of tracts required. Of the 14 patients that had supracostal tubeless procedures, three had hydrothorax requiring ICD drainage. Notably, all three had 10th ICS punctures. Other complications were comparable with other studies. There were various limitations in our study. The basic nature of the study being retrospective and descriptive in the form of a case series is one. There was no comparison group, as most of the cases with bilateral renal stones were managed simultaneously. Although the cost comparison was made with patients undergoing unilateral PCNL, this does not constitute a formal economic appraisal, and is just an indicator of the costs involved. Further randomized controlled study is required to reconfirm the benefits of tubeless SBPCNL with better quality evidence. Conclusion It is our experience that tubeless SBPCNL carried out in large volume centers by experienced urologists is a safe and effective treatment modality. Tubeless SBPCNL has its distinct advantages of obviating a second anaesthetic exposure, reduced analgesic requirement, and reduced overall hospital stay and decreased financial burden. This has an enormous impact on the outlook of an Indian patient with bilateral renal stone disease because of its cost implications. Conflict of interest None declared. References 1 Fernström I, Johannson B. Percutaneous pyelolithotomy: a new extraction technique. Scand. J. Urol. Nephrol. 1976; 10: Wickham JEA, Miller RA, Kellett MJ et al. Percutaneous nephrostolithotomy: one stage or two? Br. J. Urol. 1984; 56: Bellman GC, Davidoff R, Candela J et al. Tubeless percutaneous renal surgery. J. Urol. 1997; 157: Al-Ba adani HT, Al-Kohlany KM, Al-Adimi A et al. Tubeless percutaneous neprolithotomy: the new gold standard. Int. Urol. Nephrol. 2008; 40: Rana AM, Mithani S. Tubeless percutaneous nephrolithotomy: call of the day. J. Endourol. 2007; 21: The Japanese Urological Association 501

6 bs_bs_banner S PILLAI ET AL. 6 Weld KJ, Wake RW. Simultaneous bilateral tubeless percutaneous nephrolithotomy. Urology 2000; 56: Gupta NP, Kumar P, Aron M et al. Bilateral simultaneous tubeless percutaneous nephrolithotomy. Int. Urol. Nephrol. 2003; 35: Shah HN, Kaushik VB, Hegde SS et al. Safety and efficacy of bilateral simultaneous tubeless percutaneous nephrolithotomy. Urology 2005; 66: Wang CJ, Chang CH, Huang SW. Simultaneous bilateral tubeless percutaneous nephrolithotomy of staghorn stones: a prospective randomized controlled study. Urol. Res. 2011; 39: Yu A, Shahrour W, Andonian S. Simultaneous bilateral tubeless percutaneous nephrolithotomy:a report of 2 cases and review of the literature. Can. Urol. Assoc. J. 2012; 6: E Crook TJ, Lockyer CR, Keoghane SR et al. Totally tubeless percutaneous nephrolithotomy. J. Endourol. 2008; 22: Karami H, Gholamrezaie HR. Totally tubeless percutaneous nephrolithotomy in selected patients. J. Endourol. 2004; 18: Aghamir SMK, Hosseini SR, Gooran S. Totally tubeless percutaneous nephrolithotomy. J. Endourol. 2004; 18: Istanbulluoglu OM, Ozturk B, Cicek T et al. Case report: bilateral simultaneous tubeless and stentless percutaneous nephrolithotomy. J. Endourol. 2008; 22: Clavien PA, Barkun J, de Oliveira ML et al. The Clavien-Dindo classification of surgical complications: five-year experience. Ann. Surg. 2009; 250: Turk C, Knoll T, Petrik A, Sarica K, Straub M, Seitz C. EAU Guidelines on Urolithiasis [Cited 13 August 2013.] Available from URL: % pdf 17 Silverstein AD, Terranova SA, Auge BK et al. Bilateral renal calculi: assessment of staged v synchronous percutaneous nephrolithotomy. J. Endourol. 2004; 18: Regan JS, Lam HS, Lingeman JE. Simultaneous bilateral percutaneous nephrolithotomy. J. Endourol. 1992; 6: Holman E, Khan AM, Pasztor I, Toth C. Simultaneous bilateral compared with unilateral percutaneous nephrolithotomy. BJU Int. 2002; 89: Holman E, Salah MA, Toth C. 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Urology 2008; 72: Editorial Comment Editorial Comment from Dr Armitage to Tubeless simultaneous bilateral percutaneous nephrolithotomy: Safety, feasibility and efficacy in an Indian setting Since its first description in 1976, percutaneous nephrolithotomy (PCNL) has evolved such that it is now considered the first-line treatment for large (>2 cm) renal stones. 1 Further modifications to the procedure, such as supine positioning to allow concomitant retrograde intrarenal surgery and tubeless PCNL, where a nephrostomy tube is not inserted, are designed to improve effectiveness and minimize morbidity. In this study, the authors presented a retrospective review of their experience of tubeless simultaneous bilateral PCNL (SBPCNL). 2 They report safety and effectiveness outcomes for 170 renal units in 85 patients, and as such it constitutes the largest series of tubeless SBPCNL to date. It is noteworthy that this report originates from a very highvolume center, where more than 600 PCNL procedures are carried out each year, and that senior surgeons were undertaking the surgery. These factors are almost certainly relevant to the excellent stone-free rates that have been achieved, and the reported safety outcomes that are comparable to those in the contemporary literature. 3,4 Indeed, there remains considerable controversy regarding the role of centralization of PCNL to high-volume centers for what is considered a complex endourological procedure, and tubeless SBPCNL might introduce an additional degree of complexity still. Specific reference is made to proceeding with tubeless SBPCNL only after completion of the first side without any complication. This is clearly intuitive, but extremely important, and in keeping with an earlier study that suggested operating on the symptomatic side or more complicated stone first. 5 Where differential renal function is known, this could also be of relevance in deciding which side to embark on first. Where there is careful patient selection, and when undertaken in high-volume centers with considerable expertise, tubeless SBPCNL might offer certain advantages over staged PCNL. For example, the authors have cited reduced overall length of stay, reduced analgesic requirements and the need for only one general anesthetic. There is also reduced cost, which is of particular relevance in the context of certain healthcare systems, such as that in India. Where patients have had to travel large distances and where they are paying for their treatment, tubeless SBPCNL could be an attractive alternative to staged PCNL, particularly if further prospective studies confirm outcomes as good as those reported in this series. James N Armitage M.D., F.R.C.S.(Urol.) Department of Urology, Addenbrooke s Hospital, Cambridge, UK jim_armitage@hotmail.com Conflict of interest None declared. DOI: /iju The Japanese Urological Association