Transient apnoea for motion control during flexible ureteroscopic lithotripsy: a randomised trial
In brief
Brief apnea boosts stone-breaking efficiency and cuts surgery time by seven minutes
In a randomized trial of 150 adults, brief apnea increased active stone-breaking efficiency to 34.3 mm3 per minute, versus 27 to 28 with regular or small-volume ventilation, and shortened operations by seven minutes. Stone-free rates did not differ, and apnea required close monitoring: most patients resumed ventilation before five minutes, often after heart-rate or blood-pressure declines.
- Journal
- BJU international (Q1)
- Published
- 18 October 2026
- Study design
- Randomized controlled trial
- Evidence level
- Level 1, High (CEBM 1b)
- Authors
- Jiahuan Yu, Yi Zhou, Xiaolei Shi, Yi Liu, Ziyu Fang, Min Liu, et al.
- PMID
- 42893851
- DOI
- 10.1111/bju.70505
Why clinicians should know about it
- Picked for Urology (top studies of the week, 25 October 2026): Transient apnoea improved lithotripsy efficiency, no serious complications
Abstract
OBJECTIVES: To determine whether transient apnoea (TA) during flexible ureteroscopic laser lithotripsy improves active lithotripsy efficiency compared with regular mechanical ventilation (RMV) and small tidal-volume ventilation (STVV). PATIENTS AND METHODS: In this single-centre, three-arm randomised trial, 150 adults with a single computed tomography (CT)-confirmed renal, ureteropelvic, or proximal ureteric stone measuring 10-<20 mm were assigned one-to-one-to-one to RMV, STVV, or TA. TA followed 5-min 100% oxygen pre-oxygenation, with 9-min maximum and pre-specified stopping criteria under continuous anaesthetic monitoring. The primary endpoint was active lithotripsy efficiency, defined as CT-estimated stone volume divided by elapsed active lithotripsy time. Analyses followed the intention-to-treat principle. RESULTS: The mean (standard deviation) active lithotripsy efficiency was 27.8 (8.9), 26.6 (8.0), and 34.3 (10.0) mm3/min with RMV, STVV, and TA, respectively (P < 0.001). TA increased adjusted efficiency by 5.9 mm3/min vs RMV (95% confidence interval [CI] 2.2-9.6 mm3/min) and 6.8 mm3/min vs STVV (95% CI 3.3-10.2 mm3/min). The median active lithotripsy time was 27.5, 26.5, and 22.0 min (P = 0.001); total operative time was 50.0, 50.0, and 43.0 min (P = 0.002); and surgeon-rated targeting stability scores were 7.0, 7.0, and 9.0 (P < 0.001), respectively. Postoperative Day 1/1-month stone-free rates were 88%/92%, 80%/96%, and 88%/90%, respectively, with no significant between-group differences. The median (interquartile range) achieved apnoea duration was 5.0 (4.5-6.8) min; 46/50 resumed ventilation before the 9-min maximum, most commonly for heart-rate decline/bradycardia (n = 27) or blood-pressure decline/hypotension (n = 20). No patient had a peripheral oxygen saturation <90% or a Clavien-Dindo Grade ≥III complication; transient hypercapnia and respiratory acidosis improved after ventilation resumed. CONCLUSION: Transient apnoea improved lithotripsy efficiency and shortened operative time compared with RMV and STVV, with higher surgeon-rated targeting stability. The benefit was primarily intraoperative, without evidence of greater postoperative stone clearance. Protocolised TA may provide a brief intraoperative motion-control option with pre-oxygenation, continuous anaesthetic monitoring, and individualised termination.
Abstract as published, via PubMed.
For healthcare professionals. The summary is generated by AI from the published abstract, and the evidence level is assigned automatically from the study design on the Oxford CEBM hierarchy. Neither is medical advice. Read the full paper before changing practice.