Flexible Ureteroscopy, Tidal Volume, Urolithiasis
Conditions
Brief summary
The goal of this prospective clinical trial is to evaluate how intraoperative tidal volume settings affect surgical parameters and outcomes in adult patients undergoing flexible ureteroscopy (fURS) for kidney stones. The participant population includes patients over 18 years of age with unilateral, single renal stones located in the upper/middle calyx or renal pelvis. This study aims to answer are: Does intraoperative tidal volume influence operative time and surgical efficiency during fURS? Does tidal volume affect laser energy use, lasing efficiency, stone-free rates, and complication rates (infection or bleeding)? The investigators will compare two groups based on tidal volume recorded during anaesthesia: Group 1: Low tidal volume (\< 500 mL) Group 2: Standard tidal volume (≥ 500 mL) to determine whether tidal volume differences impact surgical performance and postoperative outcomes. Participants will: Undergo fURS performed under general anaesthesia with standard ASA monitoring, including ETCO₂ and TOF monitoring. Have their respiratory parameters (tidal volume, peak airway pressure, PEEP, respiratory rate, ETCO₂) and surgical data (operative time, laser settings, fluoroscopy use, stone-free status) recorded during and after surgery.
Interventions
PROCEDUREFlexible Ureteroscopy
Between October 2025 and December 2025, Patients who underwent fURS surgery in our clinic, with the surgical indication determined according to the EAU guidelines, were included in the study. Patients over 18 years of age with unilateral, single stones located in the upper or middle calyx or in the renal pelvis were included in the study. Patients with chronic obstructive pulmonary disease, pregnancy, a history of abdominal, retroperitoneal, or thoracic surgery, kidney anomalies, or stones located in the lower calyx were excluded.
Sponsors
Tarik Emre Sener
Study design
Allocation
NON_RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
Age ≥18 years Unilateral, single kidney stones located in the upper or middle calyx or in the renal pelvis
Exclusion criteria
Chronic obstructive pulmonary disease (COPD) Pregnancy History of abdominal, retroperitoneal, or thoracic surgery Kidney anomalies Stones located in the lower calyx
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Correlation Between Intraoperative Respiratory Parameters and Surgical Outcomes | 2 months | Respiratory parameter measured: Tidal Volume (mL/kg) Measurement tool: Anaesthesia ventilator/monitoring system Unit: milliliters per kilogram (mL/kg) Surgical outcomes assessed: Stone-free rate (%), assessed by postoperative non-contrast CT scan Operative time (minutes), recorded from surgical logs Complications, graded using the Clavien-Dindo classification The objective is to determine the statistical correlation between tidal volume and each of these surgical outcomes. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Correlation Between Intraoperative Respiratory Parameters and Seconder Outcomes | 2 months | Operative time (minutes), recorded from surgical logs Surgical efficiency (stone volume / operative time, mm³/min) Laser time (seconds), recorded from laser console Laser energy used (Joules), recorded from laser console Lasing efficiency (stone volume / lasing time, mm³/sec) Complications, graded using the Clavien-Dindo classification Bleeding rate (%), incidence of significant intra- or postoperative bleeding Infection rate (%), incidence of postoperative urinary tract infection Length of hospital stay (days), total postoperative hospitalization |
Countries
Turkey (Türkiye)
Outcome results
None listed