Urolithiasis
Conditions
Keywords
RIRS, lower pole renal stones, stone-free rate, ureteral access sheath, flexible negative-pressure, lateral position
Brief summary
Retrograde flexible ureteroscopy (RIRS) is currently the first-line treatment for renal stones \< 2cm. Lower pole renal stones(LPS) are a difficult problem for urologists. The flexible negative pressure suction ureteral sheath(f-UAS) can facilitate RIRS to flush out the fragments and dust in time, and provide a clear vision and reduce the renal pelvis pressure(RPP) during operation.Standard lithotomy position is the most commonly used position for RIRS. Besides, T-tilt position is also available for RIRS in special cases. Investigators were inspired by this and proposed the lateral position, which is available in cases of LPS.In long-term practice, investigators have found that the change of position and the use of f-UAS can improve stone-free rate(SFR). Investigators aimed to conduct a prospective randomized controlled trial to compare the SFR of different positions and different ureteral sheaths.
Detailed description
Urolithiasis was one of the most frequently noted diseases in urology clinic, with an incidence ranged from 5 to 15% around the world. Retrograde flexible ureteroscopy (RIRS) is currently the first-line treatment for renal stones \< 2cm in size. Lower pole renal stones(LPS) are a difficult problem for urologists. The inborn sharp infundibular-pelvic angle (IPA) designated an inferior stone-free rate(SFR) of 65-82.5% in LPS when compared to middle and/or upper pole stone. The flexible negative pressure suction ureteral sheath(f-URS) can facilitate RIRS to flush out the fragments and dust in time, and provide a clear vision and reduce the renal pelvis pressure(RPP) during operation. Therefore, in cases of LPS, f-URS combined with RIRS may show advantages. However, there is currently a lack of relevant prospective randomized controlled studies. Standard lithotomy position is the most commonly used position for RIRS. Besides the standard lithotomy position, other positions, such as the T-tilt position, are also available for RIRS in special cases. Investigators were inspired by this and proposed the lateral position, which is available for RIRS in cases of LPS.Theoretically, in standard lithotomy position, the renal pelvis and renal calyces were mostly distributed in a '-\<' shaped structure on the horizontal plane. However, the renal pelvis and renal calyxes would be stood up in a 'Y'-shaped structure when patients laid in lateral position. And gravity will make the calyceal stones at the dome fall into the renal pelvis naturally during the lithotripsy. In long-term clinical practice, researchers have found that the change of position and the use of f-UAS can improve SFR. The investigators aimed to conduct a prospective randomized controlled trial to compare the SFR of different positions and different ureteral sheaths.
Interventions
PROCEDURERIRS with f-UAS, lateral position
In this intervention, patients were placed on operating table in lateral position. The coronal plane of the patient body was perpendicular to the operating table. The upper limbs were extended and fxed with brackets. A f-UAS is placed under the pelvi-ureteric junction (PUJ) in RIRS. The tip of the UAS has good flexibility and deformability. It can passively bend with the bending of the flexible ureteroscope (f-URS).
PROCEDURERIRS with f-UAS, lithotomy position
In this intervention, patients were placed on operating table in lithotomy position. This position is common and standard. A f-UAS is placed under the pelvi-ureteric junction (PUJ) in RIRS. The tip of the UAS has good flexibility and deformability. It can passively bend with the bending of the flexible ureteroscope (f-URS).
PROCEDURERIRS with traditional UAS, lateral position
In this intervention, patients were placed on operating table in lateral position. The coronal plane of the patient body was perpendicular to the operating table. The upper limbs were extended and fxed with brackets. A traditional UAS is placed under the pelvi-ureteric junction (PUJ) in RIRS.
PROCEDURERIRS with traditional UAS, lithotomy position
In this intervention, patients were placed on operating table in lithotomy position. This position is common and standard. A traditional UAS is placed under the pelvi-ureteric junction (PUJ) in RIRS.
Sponsors
The First Affiliated Hospital of Guangzhou Medical University
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to 70 Years
Healthy volunteers
No
Inclusion criteria
* LPS with a diameter of 10-20 mm * American Society of Anesthesiologists(ASA) score Ⅰ,Ⅱ and Ⅲ * Adult patients
Exclusion criteria
* Ureteric stricture * Urethral deformity * Renal malformation, including horseshoe kidney, ectopic kidney and transplanted kidney * Pregnancy * Multiple stones in diferent calyces, including upper pole and middle pole
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Stone-free rate | 1 day | A low-dose and ultrathin 2-mm spiral CT was performed at 1 day postoperatively for evaluation of fnal SFR. Stone-free status was defined as no fragments observed or clinically insignifcant residual fragments (CIRF)\<2 mm. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Operative time | During surgery | Surgery duration, minutes |
| Hemoglobin drop | 1 day after surgery | Change of hemoglobin level 1 day after surgery comparing to pre-operative value, g/L |
| Hospital stay | 1 week | Duration of hospital stay after surgery, days |
| Complication rate | 1 month after sugery | Complication is defined as any adverse event occurred intraoperatively or ≤1 month postoperatively, including intraoperative bleeding, postoperative pain and so on.The investigator will invaluate perioperative complications by modified Clavien system |
Countries
China
Contacts
Primary ContactGuohua Zeng, Ph.D and M.D
Backup ContactWen Zhong, Ph.D and M.D
Outcome results
None listed