Local Anesthetic Flexible Ureterorenoscopy in the Management of Urolithiasis

Introduction

Ureterorenoscopy (URS) is increasingly performed in the evaluation and management of upper tract pathology. Although local anesthetic (LA) flexible cystoscopy is well established, ^1,2 URS has been performed traditionally under general or regional anesthesia. There has been an understandable reticence to perform ureteroscopy under local anesthesia because of patient pain, or fear of ureteral injury secondary to patient movement.

However, there are an increasing cohort of patients presenting with complicated renal tract calculi who are unwilling or unfit for general or regional anesthesia. ^3,4 This is most commonly as a consequence of increased risk secondary to comorbidity. In this cohort, with imperative reasons to intervene, options, including percutaneous nephrostomy and long-term LA ureteral stents, are associated with significant comorbidity. ^5,6

We present our institution's experience of LA URS.

Methods

We retrospectively reviewed the records of all patients who had URS for urolithiasis under local anesthesia at our institution from January 2007 to October 2018.

In total 78 patients were included in the final cohort as they were performed under local anesthesia. During the same time period, we performed >1000 ureteroscopies under general or regional anesthesia. There were 45 men and 33 women with a mean age of 68 years (range 28–92).

Patients were scored using the Charlson comorbidity index. All patients were assessed by a consultant anesthetist who deemed that the patients had a high morbidity and/or mortality rate for general anesthesia and were not suitable for regional anesthesia.

Procedure

Patients were fully consented before the procedure with alternative options discussed.

Patients were positioned in the supine position. None of the patients had preoperative analgesics. We do not use ureteral access sheaths. Standard antibiotic prophylaxis was 3 mg/kg intravenous gentamicin. Lubricating gel containing lidocaine (10 mL lubricating gel with 2% lidocaine) was administered per urethra. The flexible ureteroscope (Olympus P5, 8.4F ureteroscope, single 3.6F port) was passed directly into the bladder under vision. The ureteroscope was subsequently passed into the ureteral orifice, with or without the use of a hydrophilic guidewire. We alternated continuous low-pressure irrigation and aspiration of fluid according to views and intraoperative requirements. Fragmentation of calculi was undertaken using a holmium:YAG laser. Basket retrieval of fragments was undertaken as necessary.

Follow-up imaging, with kidney, ureter, and bladder radiograph and ultrasonography renal tract, were organized at 3 months postoperatively. Stone free was defined as no evidence of remaining stones intraoperatively and no stones on three monthly postoperative imaging.

Results

*Eighty-five ureteroscopies were undertaken in 78 patients for urinary tract calculi. All patients tolerated the procedure, with only lubricating gel per urethra, and none were abandoned because of pain.

Mean Charlson comorbidity score was 5.2. In total 70% of patients were anticoagulated. In total 58% of patients were men and 53% of procedures were performed on the left kidney. Indications for URS included pain (68%) and renal failure (15%). Totally 10% of patients had been stented before ureteroscopy, predominantly because of preceding sepsis. The majority of patients had unprepared ureters. Median hospital stay was 1 day (range 0–37). A few patients had prolonged hospital stays, predominantly because of delays awaiting community social care placement, unrelated to their surgery.

All patients tolerated the procedure and none required additional analgesia during the procedure. The overall stone-free rate was 84% after the first procedure. Nine percent (n = 7) of patients required a second LA URS. The median stone size was 8 mm (interquartile range: 5–12). Table 1 shows stone-free rate according to stone location. Sixteen (19%) patients were left with a ureteral stent after their ureteroscopy.

There were no complications above Clavien Grade 2. Two patients had ureteral injuries (one passage of guidewire outside of the ureter, one extravasation of contrast), both were managed with a ureteral stent at the same sitting and required no additional intervention for this complication. Neither of these complications were a consequence of patient movement. There were no other intraoperative complications. Postoperative complications included urinary tract infection and renal colic (Table 2).

Discussion

As urologists, we are facing an increasingly elderly and comorbid population. ^{7 –9} With imperative indications, including obstructing ureteral calculi, these patients have been managed with morbid temporizing solutions, including percutaneous nephrostomy and long-term ureteral stenting. With the miniaturization of ureteroscopes ¹⁰ and technical modifications to limit pain, this study shows that LA ureteroscopy is a valuable addition to the armamentarium. We report the first series to describe URS using solely LA lubricating gel per urethra.

In the comorbid patient, the main advantage of LA ureteroscopy is the absence of the complications associated with general/regional anesthesia. ¹¹ In addition, there are purported advantages pertaining to cost and length of hospital stay. ¹² The median length of stay was 1 day in this cohort; however, the majority could have been performed as day case procedures if social circumstances had allowed.

In comparison with other studies of LA ureteroscopy, our stone-free rate of 84% is comparable. ^13,14 Park and colleagues in their study of 55 patients, with none in the upper ureter, showed stone-free rates of 93%. ¹² Although it should be noted that Park and colleagues used a semirigid ureteroscope and preoperative intramuscular pethidine. Sallami et al. in their ureteroscopy study, which used an LA penile block, showed success rates of 84%; however, this study predominantly comprised distal ureteral stones. ¹⁵ Yalçinkaya et al. and Abdel-Razzak and Bagley in their ureteroscopy series under sedation showed similar success rates of 83% and 88%. ^16,17

Our overall complication rate (8.2%) is consistent with published general anesthesia series of URS. ¹⁸ The purported risk that patient movement may contribute to ureteral injury was not seen in our series. Indeed, in our experience the procedures were well tolerated by patients. This has been shown in previous studies; Vögeli and coworkers showed comparable complications for ureteroscopy irrespective of choice of anesthesia. ¹⁹ Other studies have shown significant failure rates (18%) associated with pain in ureteroscopies undertaken using only local anesthesia. ²⁰ In contrast, in our study, no failures were associated with pain. We feel that this is secondary to the technical modifications that we have employed. First, by using a small diameter flexible ureteroscope, the feeling of discomfort within the urethra and bladder is minimized. Second, we maintain low pressure, with frequent aspiration and judicious use of low pressure irrigation, thus minimizing renal pelvis pressures and associated pain.

No procedures were abandoned because of pain and seven patients came back for a repeat ureteroscopy. However, we do acknowledge that a lack of pain scores is a limitation of this retrospective study.

Of course, extracorporeal shock wave lithotripsy is an important option in this cohort who are unfit for general anesthesia. ²¹ However, many of our cohort were anticoagulated with indications that preclude cessation. In addition, because of limited mobility, many of this cohort would have had difficulty attending multiple-staged sessions of ESWL. ²²

Conclusions

A combination of technical modifications and technological advancement mean that ureteroscopy using only LA lubricating per urethra is a viable treatment option in those patients with comorbidities that preclude general or regional anesthesia.