Upper Urinary Tract. Kerri T. Barnes, Megan T. Bing and Chad R. Tracy. Objective. Patients and Methods. Conclusion. Results. Keywords.

Transcription

1 Upper Urinary Tract Do ureteric stent extraction strings affect stent-related quality of life or complications after ureteroscopy for urolithiasis: a prospective randomised control trial Kerri T. Barnes, Megan T. Bing and Chad R. Tracy Department of Urology, University of Iowa, Iowa City, IA, USA This work was presented at the 213 AUA annual meeting Objective To determine whether ureteric stent extraction strings affect stent-related quality of life (QoL) or increase complications after ureteroscopy (URS) for stone disease. Patients and Methods In all, 68 patients undergoing URS (October 211 to May 213) for stone disease were randomised to receive a ureteric stent with or without an extraction string. Patients completed the Ureteric Stent Symptom Questionnaire (USSQ) on postoperative days 1 and 6, and 6 weeks after. Pain was assessed at. Adverse events, including early, stent migration, retained stent, urinary tract infection (UTI), emergency room (ER) visits and postoperative phone calls were monitored. Results There was no difference in stent-related QoL as measured by the USSQ between those with and without a stent extraction string, pain at between those who pulled their stent independently vs those who underwent cystoscopy for, or in the rate of UTIs, ER visits or phone calls between groups. Five patients (four female, one male) removed their stent early by inadvertently pulling the string; none required replacement. Patients without a string had a significantly longer period with the postoperative ureteric stent (1.6 vs 6.3 days, P <.1). One patient without a stent string retained her ureteric stent for 6 months, which was removed by cystoscopy without incident. Conclusion Ureteric stent extraction strings may offer several advantages without increasing stent-related urinary symptoms, complications, or postoperative morbidity. Keywords ureteroscopy, nephrolithiasis, ureteric stent, Ureteric Stent Symptom Questionnaire (USSQ) Introduction Previous studies have shown that ureteric stent placement increases postoperative patient morbidity and negatively affects quality of life (QoL) [1,2]. Additionally, randomised prospective clinical trials have shown that ureteric stents may be omitted in certain patients undergoing routine ureteroscopy (URS) [3,4]. Nonetheless, 8% of urologists report leaving an indwelling ureteric stent after uncomplicated URS for stone disease []. Because of the discrepancy in available studies and differing surgeon practices in leaving a routine stent, additional efforts have focused on limiting stent morbidity through decreasing dwell time and modifying stents with various materials, impregnated drugs, and various configurations [6]. While there is clearly morbidity associated with the stent itself, there is additional morbidity due to a secondary procedure for cystoscopic extraction. Current ureteric stents are typically packaged with an extraction string suture, allowing for removal without cystoscopy. However, the use of these strings is highly variable in practice ranging from string removal before placement, to in-office cystoscopic string extraction, and independent patient extraction at home. Surgeons who do not use a string stent may have concerns about accidental removal, potential for increased stent-related symptoms or complications (e.g. UTI), and the possibility of stent retention. Perhaps secondary to these concerns, there is a paucity of studies investigating the BJU International 213 BJU International doi:1.1111/bju.1241 BJU Int 214; 113: 6 69 Published by John Wiley & Sons Ltd. wileyonlinelibrary.com

2 Barnes et al. use of extraction strings and whether or not they are used is rarely mentioned in any studies evaluating stent symptoms. We previously reported results of a retrospective review showing no difference in post-procedure-related events between patients with ureteric stents with or without extraction strings after URS for stone disease [7]. As retrospective studies are complicated by multiple confounding variables, we designed a prospective, randomised trial using validated outcomes instruments to compare outcomes in patients who underwent ureteric stent placement with and without extraction strings after URS for stone disease. Patients and Methods In all, 41 patients undergoing routine URS for stone disease by one of four surgeons at our institution between October 211 and May 213 were approached preoperatively for participation in this randomised study. Patients with a solitary kidney, preoperative UTI, congenital anomaly of the urinary tract, who were pregnant, undergoing bilateral URS or those potentially requiring a ureteric stent for >7 days postoperatively were excluded. The study was approved by the University of Iowa Institutional Review Board. After the completion of URS, patients who continued to meet eligibility criteria were randomised using sealed envelopes to receive a ureteric stent either with or without an extraction string. To decrease selection bias, attending surgeons were blinded to patient participation in the study until the decision was made to place a postoperative stent. All stents were 6 F Cook Medical (Bloomington, IN) Universa soft ureteric stents with varying lengths based on patients height. The stents were inserted either under direct visualisation using a rigid cystoscope with fluoroscopic guidance or with fluoroscopic guidance alone. Before placing stents with extraction strings, the suture knot on the end of the string was removed and a new knot was tied, leaving a short, 1 2 cm air knot as previously described [6]. The string was shortened to several centimetres past the urethral meatus, leaving enough length for men to have an erection and women to easily find the string for removal. The string was not secured to the patient s skin to prevent a loop that could easily be entangled and lead to premature extraction. All patients were prescribed perioperative antibiotics and postoperative α-blockers, pain medications, and anticholinergics as needed. All participants were asked to complete the validated Ureteric Stent Symptom Questionnaire (USSQ) on postoperative days (POD) 1 and 6 and 6 weeks after, which served as the control. The USSQ consists of several domains including urinary symptoms, pain, general health, work performance, and sexual matters. Participants with extraction strings removed stents at home on POD 7. Those without strings came for in-office cystoscopy on POD 7 14, allowing for scheduling restraints. At the time of, Fig. 1 Study design and enrolment. 33 patients 1 patients screened 41 patients approached 1 patients consented 68 patients randomised No 3 patients 114 Excluded 9 solitary kidney 78 preoperative UTI 27 bilateral ureteroscpoy 296 Refused 22 did not want string 66 wanted string 27 refused research 37 Screen Failures 2 longer stent time 8 no stent placed 4 bilateral ureteroscopy participants completed a Likert visual analogue scale (VAS) that rated pain from 1. Adverse events including early stent removal, stent migration, retained stents, culture-confirmed UTI, emergency room (ER) visits, and phone calls were monitored. Sample size was calculated based on previous results of the USSQ validation study [8]. In all, 76 patients, 38 per arm, would be sufficient to detect a difference of 2% and 3% in the mean index scores for the urinary symptom and general health domains, respectively, with 8% power. The mean scores for each of the USSQ domains were compared using the two-tailed Student s t-test. Categorical variables were analysed using the chi-square test. Adverse events were analysed using Fisher s exact test. All reported P values were two-sided with statistical significance set at.. Results In all, 68 patients were randomised: 33 with stent string and 3 with no string (Fig. 1). Surveys were returned by 42 of the 68 patients randomised (62%). There was no difference between groups in regard to gender, age, body mass index or side (Table 1). The index scores for the USSQ domains over the study period are shown in Fig. 2. There was no difference in urinary symptoms, pain, general health, or work performance between the groups on either POD 1, 6 or 6 weeks after. Table 2 shows VAS pain scores at. Overall, the mean pain score was 2. in those with a stent string and 3.1 in those with no string undergoing cystoscopy (P =.4). The mean stent dwell-time was 1.6 days in patients without a string and 6.3 days in patients with a string (P <.1). Other potential complications from the presence of the extraction string are listed in Table 3. Of the 33 patients with a 66 BJU International 213 BJU International

3 Stent extraction strings and QOL/complications after URS for urolithiasis Fig. 2 Index scores for USSQ domains on POD 1 and 6, and 6 weeks after. (A) Urinary symptoms. (B) VAS pain scores. (C) General health. (D) Work performance. A Urinary Symptoms No B VAS Pain Scores No C General Health No D 6 Work Performance No Table 1 Baseline characteristics of study population. Variable No string P Number of patients 33 3 Male, n Female, n Mean age, years Mean BMI, kg/m Left side, n Right side, n Stone location: n kidney ureter combination Mean stone size, mm Preoperative stent, n First kidney stone, n Previous stone surgery, n Table 2 VAS pain scores at. Pain score, mean (SD, range) No string P Overall 2. (2.8, 1) 3.1 (2.8, 1).4 Men 4.3 (3.8, 1 1) 2 (1.1, 1 4).38 Women 2.1 (2.8, 8) 4.6 (2.9, 1).67 stent string, five (1%) inadvertently removed their stent before POD 7 (one male, four females) at 4 days postoperatively, none of which required replacement. In all, 32/33 patients (97%) with a stent string were able to remove Table 3 Complications associated with the presence of an extraction string. Complication (n = 33), n No string (n = 3), n P Stent dislodgement (1 male, 4 female). Stent migration 1. UTI 3 (1 male, 2 female) 3 (1 male, 2 female) 1. ER visit 3.71 Phone calls Retained stent 1.89 their stent at home without difficulty, while one male patient with a stent string presented to clinic for help with removal secondary to anxiety. There were no incidents of proximal stent migration requiring URS for. There was no difference in rates of UTI between the groups, with three patients in each group presenting with symptomatic UTI (one male, two females). There was no difference in the number of ER visits or postoperative phone calls between groups. One female participant without a string was lost to follow-up and retained her ureteric stent for 6 months. It was subsequently removed by in-office cystoscopy without incident. Discussion There is a wide variability in the use of extraction strings for postoperative after routine URS. Reasons for this variability are unclear, but probably relate to surgeon BJU International 213 BJU International 67

4 Barnes et al. preference and a perceived concern for postoperative symptoms and complications. Based on this randomised prospective study, these concerns may be unfounded as we were unable to find a difference in stent-related symptoms between patients with and without ureteric stent extraction strings as measured by the validated USSQ. Furthermore, there was no difference in the incidence of postoperative complications, including symptomatic UTIs, ER visits or patient phone calls between groups. As for most previous studies [1,2,9], the present study confirms that ureteric stents negatively affect QoL during the time they are left indwelling. Therefore, any decrease in stent dwell time should lead to improved patient outcomes and fewer days of decreased QoL. While every attempt was made to schedule patients at 1 week for cystoscopic stent extraction, stent dwell time was significantly longer for those presenting for cystoscopic extraction vs those with the freedom to remove their stent at home independent of their schedule or that of their surgeon (1.6 vs 6.3 days, P <.1). Extraction string placement may also alleviate the concern of the forgotten stent due to increased visibility of the exteriorised string and may also prevent proximal stent migration, which has been reported in up to 8% of cases [4]. Despite prospectively following patients and recording those with a stent, one patient in the cystoscopic cohort failed to follow up on multiple occasions, resulting in a stent dwell time of 6 months. In addition to the effects on QoL, patient convenience and satisfaction may be directly correlated with at-home stent removal. This is particularly true at a tertiary care centre where patients may travel significant distances for evaluation and treatment. On average, patients in the present cohort saved an average of a 28 km (177 miles) round trip travel by removing their stents at home. While we did not do a formal cost analysis in the present study, ureteric stent extraction by string may lead to obvious healthcare and patient cost savings. Importantly, stent strings eliminate the need for cystoscopy, which currently is reimbursed at $ (USA dollars) [1,11]. If all patients who underwent URS during the present 18-month study period had an extraction string placed, this would have resulted in $97 cost savings at our hospital alone. In addition to healthcare-related costs, there are direct financial benefits to patients in having their stent removed at home, including potentially fewer lost days of work as well as mitigation of travel costs. Recent estimates by the American Automobile Association indicate that the cost of driving a car averages $.2.6/km ($.4.9/mile) [12], such that home removal for patients in the present study saved an out of pocket expense of $68 16 per patient. Although little is known about pain associated with cystoscopic stent extraction using flexible cystoscopy, both men and women appear to tolerate routine flexible cystoscopy for other disorders relatively well, although men generally have higher VAS pain scores than women [13,14]. A recent study using VAS pain scores to evaluate pain during stent removal using a rigid cystoscopy showed no difference in pain in patients undergoing cystoscopy vs extraction by stent string although there were only 13 patients in the later cohort [1]. We hypothesised that patients who could remove their stent using a string would have lower pain scores at removal than those undergoing cystoscopy. Somewhat surprisingly, similar to the above study by Kuehhas et al. [1], we were unable to show a difference in VAS pain scores at in the present cohort. While it may be that there is truly no difference in pain between extraction methods, the present study may be biased by the proportionally higher number of women in the overall cohort, who may report lower baseline pain scores with cystoscopy relative to men. Additionally, we routinely use intraurethral lidocaine jelly for in the office, which may decrease pain associated with stent extraction [13]. While the present results are encouraging and lend support for the use of ureteric extraction strings, there are several limitations that need to be considered. As has been found in multiple other survey studies, response to the USSQ survey was lower than anticipated, so that reaching our target enrolment was not possible within the constraints of the present study and may have underpowered the study to detect slight differences in patient outcomes. However, survey compliance was similar between cohorts and only slightly lower than similar studies using the USSQ as a survey tool [9,16 18]. Furthermore, the accrual rate was also lower than anticipated, with only 2% of patients approached agreeing to participate. This was generally due to anxiety over having to remove their ureteric stent independently, a preference for one technique due to prior experience, or a concern over having a string coming out of their urethral meatus. These concerns were particularly amplified in men, which led to a higher than expected rate of female participants in the present study, a fact which may limit the generalizability to the typical stone population where the prevalence of stones is higher in men [19]. Despite the difficulty in accruing a large number of patients, the results of the present study mirror those of our larger retrospective study, which also showed no difference in ER visits, unexpected clinic visits, or phone calls based on the presence or absence of an extraction string [7]. The low participation rate does highlight that patients often have a strong preference for extraction method and that practitioners should consult with their patients before making a decision on whether or not to leave an extraction string. While strings may be of benefit for the above mentioned reasons, it is important to note that extraction strings may not be appropriate in all cases. In the present study, we found that 1.2% of patients with an extraction string prematurely removed the stent, which is significantly higher than the 4.7% 68 BJU International 213 BJU International

5 Stent extraction strings and QOL/complications after URS for urolithiasis previously reported in our retrospective study. Reasons for the higher rate in the present cohort may be improved reporting due to the prospective nature of the study or due to a higher percentage of women (64% vs 8%), who tend to be more likely to prematurely removal their stents, presumably secondary to female hygiene habits. Therefore, caution should be taken in cases of ureteric perforation, endopyelotomy, solitary kidney or pyelonephritis, where there may be a more imperative need for prolonged stenting. In conclusion, the use of ureteric stent extraction strings after URS for stone disease does not increase stent-related urinary symptoms, complications, or morbidity during removal, with equivalent rates of symptomatic UTI, ER visits and postoperative phone calls. While they may not be appropriate for all patients, the use of extraction strings may improve patient convenience, eliminate unnecessary decline in QoL from longer dwell time, and decrease costs to the healthcare system as well as the patient. Conflict of Interest None declared. References 1 Tolley D. Ureteric stents, far from ideal. Lancet 2; 36: Giannarini G, Keeley FX Jr, Valent F et al. Predictors of morbidity in patients with indwelling ureteric stents: results of a prospective study using the validated Ureteric Stent Symptom Questionnaire. BJU Int 211; 17: Denstedt JD, Wollin TA, Sofer M, Nott L, Weir M, D A Honey RJ. A prospective randomized controlled trial comparing nonstented versus stented ureteroscopic lithotripsy. J Urol 21; 16: Haleblian G, Kijvikai K, de la Rosette J, Preminger G. Ureteral stenting and urinary stone management: a systematic review. J Urol 28; 179: Netto NR Jr, Ikonomidis J, Zillo C. Routine ureteral stenting after ureteroscopy for ureteral lithiasis: is it really necessary? J Urol 21; 166: Lim KT, Kim YT, Lee TY, Park SY. Effects of tamsulosin, solifenacin, and combination therapy for the treatment of ureteral stent related discomforts. Korean J Urol 211; 2: Bockholt N, Wild T, Gupta A, Tracy CR. Ureteric stent placement with extraction strings: no strings attached? BJU Int 212; 11: E Joshi HB, Newns N, Stainthorpe A, MacDonagh RP, Keeley FX Jr, Timoney AG. Ureteric stent symptom questionnaire: development and validation of a multidimensional quality of life measure. J Urol 23; 169: Calvert R, Wong K, Chitale S et al. Multi-length or 24 cm ureteric stent? A multicenter randomized comparison of stent-related symptoms using a validated questionnaire. BJU Int 213; 111: Centers for Medicare & Medicaid Services. Hospital Outpatient Prospective Payment System. Available at: -and-education/medicare-learning-network-mln/mlnproducts/ downloads/hospitaloutpaysysfctsht.pdf. Accessed 9 December Sutherland TN, Pearle MS, Lotan Y. How much is a kidney worth? Cost-effectiveness of routine imaging after ureteroscopy to prevent silent obstruction. J Urol 213; 189: American Automobile Association. Your Driving Costs How Much Are YouReallyPayingToDrive, 213 Edn. Available at: Accessed 2 August Aaronson DS, Walsh TJ, Smith JF, Davies BJ, Hsieh MH, Konety BR. Meta-analysis: does lidocaine gel before flexible cystoscopy provide pain relief? BJU Int 29; 14: Gee JR, Waterman BJ, Jarrard DF, Hedican SP, Bruskewwitz RC, Nakada SY. Flexible and rigid cystoscopy in women. JSLS 29; 13: KuehhasF,MiernikA,SharmaVetal.A prospective evaluation of pain associated with stone passage, stents and using a visual analogue scale. Urology 213; 82: Joshi HB, Stainthorpe A, MacDonagh RP, Keeley FX Jr, Timoney AG, Barry MJ. Indwelling ureteral stents: evaluation of symptoms, quality of life and utility. J Urol 23; 169: Lee C, Kuskowski M, Premoli J, Skemp N, Monga M. Randomized evaluation of ureteral stents using validated symptom questionnaire. J Endourol 2; 19: Davenport K, Kumar V, Collins J, Melotti R, Timoney AG, Keeley FX Jr. New ureteral stent design does not improve patient quality of life: a randomized, controlled trial. J Urol 211; 18: Scales CD Jr, Smith AC, Hanley JM, Saigal CS, Urologic Diseases in America Project. Prevalence of kidney stones in the United States. Eur Urol 212; 62: 16 Correspondence: Chad R. Tracy, University of Iowa, Department of Urology, 2 Hawkins Dr 3 RCP, Iowa City, IA , USA. chad-tracy@uiowa.edu Abbreviations: ER, emergency room; POD, postoperative days; QoL, quality of life; URS, ureteroscopy; USSQ, Ureteral Stent Symptom Questionnaire; VAS, visual analogue scale. BJU International 213 BJU International 69