Hemodynamic Effects of Surgical Position in Prone vs. Supine Percutaneous Nephrolithotomy

NCT07138872 | Recruiting

• 1 other identifier: AIBU-SBF-ABK-01
• Study Type: interventional
• Target: 84
• Locations: 1 country
• Sites: 1

Brief Summary

This prospective, randomized controlled study evaluates the hemodynamic effects of prone and supine positions during percutaneous nephrolithotomy (PNL) for large kidney stones. Surgical position may influence intraoperative and postoperative hemodynamic stability. Prone positioning can increase intrathoracic pressure and reduce venous return, whereas supine positioning may provide greater hemodynamic stability. A total of 84 patients will be randomized to undergo PNL in prone or supine positions. Primary outcomes include changes in hemodynamic parameters during surgery. Results may guide surgical position selection, especially in patients with potential hemodynamic risk.

Conditions

Percutaneous Nephrolithotomy (PCNL); Surgical Positioning; Prone Position; Supine Position; Hemodynamic Stability; Nephrolithiasis

Keywords

PCNL; Prone Position; Percutaneous Nephrolithotomy; Supine Position; Hemodynamic stability; Nephrolithiasis

Outcome Measures

Primary Outcomes (9)

• Change in Hemodynamic Parameters (Intraoperative)

  Systolic blood pressure (mmHg) will be recorded at predefined time points (preoperative baseline, intraoperative intervals, and immediate postoperative period) to assess intraoperative hemodynamic stability.

  From induction of anesthesia to the end of surgery (approximately 60-120 minutes)

• Change in Arterial Blood pH

  Arterial pH will be measured at predefined time points (preoperative, intraoperative, postoperative day 1) to evaluate metabolic changes between prone and supine groups.

  Preoperative, intraoperative, postoperative day 1

• Change in Diastolic Blood Pressure (Intraoperative)

  Diastolic blood pressure (mmHg) will be recorded at predefined time points (preoperative baseline, intraoperative intervals, and immediate postoperative period) to assess intraoperative hemodynamic stability.

  From induction of anesthesia to the end of surgery (approximately 60-120 minutes

• Change in Mean Arterial Pressure (Intraoperative)

  Mean arterial pressure (mmHg) will be recorded at predefined time points (preoperative baseline, intraoperative intervals, and immediate postoperative period) to assess intraoperative hemodynamic stability.

  From induction of anesthesia to the end of surgery (approximately 60-120 minutes)

• Change in Heart Rate (Intraoperative)

  Heart rate (beats per minute) will be recorded at predefined time points (preoperative baseline, intraoperative intervals, and immediate postoperative period) to assess intraoperative hemodynamic stability.

  From induction of anesthesia to the end of surgery (approximately 60-120 minutes)

• Change in Arterial pO₂

  Arterial oxygen partial pressure (mmHg) will be measured at predefined time points (preoperative, intraoperative, postoperative day 1) to evaluate respiratory function.

  Preoperative, intraoperative, postoperative day 1

• Change in Arterial HCO₃-

  Arterial bicarbonate (mmol/L) will be measured at predefined time points (preoperative, intraoperative, postoperative day 1) to evaluate metabolic changes.

  Preoperative, intraoperative, postoperative day 1

• Change in Oxygen Saturation

  Arterial oxygen saturation (%) will be measured at predefined time points (preoperative, intraoperative, postoperative day 1) to evaluate respiratory status.

  Preoperative, intraoperative, postoperative day 1

• Change in Arterial pCO₂

  Arterial carbon dioxide partial pressure (mmHg) will be measured at predefined time points (preoperative, intraoperative, postoperative day 1) to evaluate respiratory changes.

  Preoperative, intraoperative, postoperative day 1

Secondary Outcomes (7)

• Operative Time

  From initial skin incision until completion of stone removal (approximately 30-180 minutes).

• Anesthesia Duration

  From induction of anesthesia until termination of anesthesia and awakening of the patient (approximately 60-240 minutes).

• Intraoperative Blood Loss

  Intraoperative period (from skin incision to completion of surgery, approximately 30-180 minutes).

• Complication Rate

  From intraoperative period through hospital stay and up to 30 days postoperatively.

• Residual Stone Rate

  At postoperative 1 month, assessed by CT scan.

Study Arms (2)

Prone Position

EXPERIMENTAL

Patients in this group will undergo percutaneous nephrolithotomy (PNL) in the prone position. The procedure begins with ureteral catheter placement in lithotomy position, followed by prone positioning for renal access under C-arm fluoroscopic guidance. Stone fragmentation will be performed using pneumatic or ultrasonic lithotripters, and nephrostomy placement will be completed according to standard protocol.

Procedure: Prone Position Percutaneous Nephrolithotomy

Supine Position

EXPERIMENTAL

Patients in this group will undergo percutaneous nephrolithotomy (PNL) in the Galdakao-modified Valdivia supine position. Following general anesthesia, the ipsilateral side will be elevated 20-30°, with the ipsilateral leg extended and the contralateral leg abducted. Ureteral catheter placement will be followed by renal access under C-arm fluoroscopy. Stone fragmentation and removal will be performed using the same standardized lithotripsy and irrigation protocols as in the prone group.

Procedure: Supine Position Percutaneous Nephrolithotomy (Galdakao-modified Valdivia)

Interventions

Prone Position Percutaneous Nephrolithotomy PROCEDURE

Patients in this arm will undergo percutaneous nephrolithotomy (PNL) in the prone position. The procedure begins with ureteral catheter placement in lithotomy position, followed by prone positioning for renal access under C-arm fluoroscopic guidance. Stone fragmentation will be performed using pneumatic or ultrasonic lithotripters, and nephrostomy placement will be completed according to standard protocol.

Prone Position

Supine Position Percutaneous Nephrolithotomy (Galdakao-modified Valdivia) PROCEDURE

Patients in this arm will undergo percutaneous nephrolithotomy (PNL) in the Galdakao-modified Valdivia supine position. Following general anesthesia, the ipsilateral side will be elevated 20-30°, with the ipsilateral leg extended and the contralateral leg abducted. Ureteral catheter placement will be followed by renal access under C-arm fluoroscopy. Stone fragmentation and removal will be performed using the same standardized lithotripsy and irrigation protocols as in the prone group.

Supine Position

Eligibility Criteria

• Age: 18 Years - 80 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• ASA physical status I-III
• Presence of renal calculi indicated for PNL

You may not qualify if:

• Pregnancy
• Uncontrolled coagulopathy
• Previous renal surgery
• Severe cardiac, pulmonary, or neurological disease
• Preoperative urinary tract infection (non-sterile urine culture)
• Surgery duration \<60 minutes or \>120 minutes
• Preoperative blood transfusion
• Multiple access tracts

Sponsors & Collaborators

• Gaziosmanpasa Research and Education Hospital: lead

Study Sites (1)

Gaziosmanpaşa Training and Research Hospital

Istanbul, 34275, Turkey (Türkiye)

RECRUITING

MeSH Terms

Conditions

Deception; Nephrolithiasis

Condition Hierarchy (Ancestors)

Social Behavior; Behavior; Kidney Diseases; Urologic Diseases; Female Urogenital Diseases; Female Urogenital Diseases and Pregnancy Complications; Urogenital Diseases; Urolithiasis; Male Urogenital Diseases

Study Officials

• Burak Arslan, CLINICAL PROFESSOR OF UROLOGY

  Gaziosmanpaşa Training and Research Hospital, Urology Department, Istanbul, Türkiye

  STUDY DIRECTOR

Central Study Contacts

ARİF BURAK KEÇEBAŞ, UROLOGY CLINIC DOCTOR

CONTACT

+90 5412659978; arifkecebas@gmail.com

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER GOV
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: UROLOGY DOCTOR

Study Record Dates

• First Submitted: August 9, 2025
• First Posted: August 24, 2025
• Study Start: June 1, 2025
• Primary Completion: December 30, 2025
• Study Completion: December 30, 2025
• Last Updated: August 24, 2025

Record last verified: 2025-08

Data Sharing

• IPD Sharing: Will not share

Locations

TU (1)