An interventional study of Standard Ventilation and Hypoventilation in Kidney Stones and Nephrolithiasis, sponsored by Sultan Abdulhamid Han Training and Research Hospital, Istanbul, Turkey. Not yet recruiting at 1 site in Turkey (Türkiye). Open to participants aged 18 Years to 75 Years. Per ClinicalTrials.gov, last updated 2026-07-15.
Sponsored by Sultan Abdulhamid Han Training and Research Hospital, Istanbul, Turkey · Not applicable, Interventional, and Treatment
This randomized clinical trial will compare four ventilation strategies during retrograde intrarenal surgery performed under general anesthesia. The study aims to determine whether reducing respiratory-related kidney movement improves surgical success and decreases perioperative complications. Eighty adult patients will be randomly assigned to standard ventilation, hypoventilation, intermittent apnea ventilation, or one-lung ventilation. Surgical outcomes and perioperative complications will be compared between groups.
Retrograde intrarenal surgery is commonly performed under general anesthesia, but respiratory movement may interfere with kidney stability during the procedure. This prospective, randomized, single-center trial will compare standard ventilation, hypoventilation, intermittent apnea ventilation, and one-lung ventilation in adult patients undergoing retrograde intrarenal surgery. The primary objective is to determine whether different ventilation strategies improve surgical success by reducing kidney movement. Secondary outcomes include operative time, stone access time, fluoroscopy time, laser use time, complications, length of hospital stay, and postoperative stone-free rate.
Age 18-75 years. ASA physical status I-III. Scheduled for elective RIRS/RIRC under general anesthesia. No obstructive or restrictive pulmonary disease. No history of pneumothorax. No pulmonary mass or other significant respiratory disease. Normal coagulation parameters and not receiving antithrombotic therapy. No active urinary tract infection. Written informed consent.
Exclusion Criteria:
Age \<18 or >75 years. ASA IV. Obstructive or restrictive pulmonary disease. History of pneumothorax. Pulmonary mass or significant respiratory disease. Receiving antithrombotic therapy or abnormal coagulation. Active urinary tract infection or urinary tract anatomical abnormality. Refusal or inability to provide informed consent.
Patients will receive standard volume-controlled mechanical ventilation during retrograde intrarenal surgery under general anesthesia.
Procedure: Standard Ventilation
Patients will receive hypoventilation with reduced tidal volume and respiratory rate during retrograde intrarenal surgery under general anesthesia.
Procedure: Hypoventilation
Patients will receive intermittent apnea periods during selected surgical steps, in coordination with the surgeon.
Procedure: Intermittent Apnea Ventilation
Patients will receive one-lung ventilation during selected surgical steps, in coordination with the surgeon.
Procedure: One-Lung Ventilation
Volume-controlled mechanical ventilation using standard ventilator settings during general anesthesia.
Volume-controlled mechanical ventilation using reduced tidal volume and respiratory rate during general anesthesia.
Intermittent apnea periods applied during selected stages of retrograde intrarenal surgery to reduce kidney motion.
One-lung ventilation applied during selected stages of retrograde intrarenal surgery to reduce kidney motion.
Kidney Motion During Retrograde Intrarenal Surgery
Kidney motion during surgery will be evaluated and compared among the four ventilation strategies.
Time frame: During surgery
Stone-free Rate
Percentage of patients who are stone-free after retrograde intrarenal surgery.
Time frame: Postoperative Day 30
Operative Time
Total duration of surgery measured from the beginning to the end of the surgical procedure.
Time frame: During surgery
Fluoroscopy Time
Total fluoroscopy exposure time recorded during the procedure.
Time frame: During surgery
Laser Activation Time
Total duration of laser use during stone fragmentation.
Time frame: During surgery
Perioperative Complications
Occurrence of intraoperative and postoperative complications.
Time frame: Periprocedural
Length of Hospital Stay
Number of days of hospitalization.
Time frame: Periprocedural
Plan to share: No — Individual participant data will not be made publicly available to protect participant confidentiality.
No publications or documents are linked to this record.
This study is not yet recruiting, as verified in Jul 2026. You cannot join it, but the record below documents what was studied.
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Sultan Abdulhamid Han Training and Research Hospital, Istanbul, Turkey