General Versus Spinal Anesthesia in RIRS

Comparative Study of General Versus Spinal Anesthesia in Retrograde Intrarenal Surgery: Impact of Stone Size on Perioperative Outcomes

The impact of anesthesia type on Retrograde Intrarenal Surgery (RIRS) outcomes remains a subject of ongoing debate. Several studies have compared general anesthesia (GA) and spinal anesthesia (SA) in endourological procedures, with conflicting results regarding operative time, complication rates, and stone-free outcomes. Importantly, the interaction between anesthesia type and stone characteristics-particularly stone size-has not been fully elucidated. Therefore, this study aims to conduct a retrospective comparative analysis of general versus spinal anesthesia in patients undergoing RIRS at Qena University Hospital, with particular emphasis on the effect of stone size stratification on perioperative outcomes.

Study Overview

• Status: Not yet recruiting
• Conditions: Retrograde Intrarenal Surgery

Detailed Description

Urolithiasis is a common urological condition with a rising global incidence and prevalence, largely attributed to lifestyle, dietary factors, and metabolic disorders. The lifetime risk of developing urinary stones is estimated to be approximately 10-15%, with a high recurrence rate that imposes a significant burden on healthcare systems. Advances in minimally invasive techniques have revolutionized the management of renal calculi, with retrograde intrarenal surgery (RIRS) emerging as a safe and effective modality for treating renal stones of varying sizes and locations.

RIRS, performed using flexible ureteroscopy and laser lithotripsy, has gained widespread acceptance due to its minimally invasive nature, reduced morbidity, and favorable stone-free rates. It is particularly advantageous for managing stones less than 2 cm, although its indications have expanded to include larger and more complex stones in selected cases. Despite these advantages, several factors influence the success and safety of RIRS, including stone size, location, density, surgeon experience, and perioperative management strategies.

Among perioperative factors, the choice of anesthesia plays a critical role in determining surgical conditions and patient outcomes. General anesthesia (GA) is traditionally preferred for RIRS as it provides optimal airway control, complete immobility, and controlled ventilation, thereby facilitating precise endoscopic manipulation. In contrast, spinal anesthesia (SA) has been proposed as an alternative due to its advantages such as reduced postoperative pain, lower incidence of nausea and vomiting, and avoidance of airway-related complications. However, concerns remain regarding its limitations, including patient movement, inadequate control of respiration, and hemodynamic instability.

By evaluating stone-free rates and perioperative complications across different stone size categories, this study seeks to provide evidence-based guidance for optimizing anesthesia selection in RIRS.

• Study Type: Observational
• Enrollment (Estimated): 80

Contacts and Locations

• Study Contact: Name: Zeinab Mustafa Sayed, MD; Phone Number: +02 01009071365; Email: zeinab5aton@gmail.com

Study Locations

• Egypt
  • Qena Governorate
    • Qina, Qena Governorate, Egypt, 83511
      • Qena University
      • Contact: Zeinab Mustafa, MD; Phone Number: +02 01009071365; Email: zeinab5aton@gmail.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Probability Sample

Study Population

All eligible patients undergoing retrograde intrarenal surgery (RIRS)

Description

Inclusion Criteria:

• Adult patients (≥18 years) scheduled for elective RIRS for renal stones <2 cm.
• Written informed consent obtained.

Exclusion Criteria:

• History of previous ureteral surgery or known ureteral stricture.
• Multiple or bilateral renal stones requiring staged procedures.

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort
General Anesthesia; patients in this group receive general anesthesia for RIRS: Intravenous anesthetic induction, Endotracheal intubation, controlled ventilation, muscle relaxation and inhalational anesthetic maintenance.
Spinal Anesthesia; patients in this group receive spinal anesthesia for RIRS: Standard spinal block using bupivacaine without sedation.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Stone Free Rate	Follow-up Ultrasound/Computed Tomography (US/CT) to assess stone-free status after the first postoperative month. Success was considered as residues of <2mm or absence of any stone fragments.	after the first postoperative month.
Total opioid consumption	Total opioid consumption in the whole postoperative period is recorded	Perioperative

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Pain assessement	pain is assessed uing Numerical Rating Scale where patients are asked to select a number from 0 to 10 to quantify their pain level where 0= no pain at all and 10= worst pain imaginable	at 6 hours, 12 hours, 24 hours
Patient Satisfaction	patients are asked to evaluate their satisfaction using a simple 4 point likert scale, where 4= Very Satisfied, 3= Satisfied, 2= Dissatisfied, 1= Very Dissatisfied	Perioperative
PACU stay	the duration of stay in PACU (postanesthetic care unit) is recorded	Perioperative

Collaborators and Investigators

• Sponsor: South Valley University

Study record dates

Study Major Dates

• Study Start (Estimated): July 1, 2026
• Primary Completion (Estimated): August 1, 2026
• Study Completion (Estimated): September 1, 2026

Study Registration Dates

• First Submitted: June 15, 2026
• First Submitted That Met QC Criteria: June 18, 2026
• First Posted (Actual): June 24, 2026

Study Record Updates

• Last Update Posted (Actual): June 25, 2026
• Last Update Submitted That Met QC Criteria: June 22, 2026
• Last Verified: June 1, 2026

More Information

Terms related to this study

• Keywords: Perioperative Outcomes; General Anesthesia; Spinal Anesthesia; RIRS
• Other Study ID Numbers: AIP02942671

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No