Assessment of Renal Perfusion Using Ultrasound and Near-Infrared Spectroscopy in Patients Undergoing Minimally Invasive Abdominal Surgery

NCT07635160 | Recruiting

• 1 other identifier: CUC-RenalPerfusion-2026
• Study Type: observational
• Target: 51
• Locations: 1 country
• Sites: 1

Brief Summary

This prospective observational study aims to evaluate renal perfusion in adult patients undergoing elective minimally invasive abdominal surgery. Renal perfusion will be assessed using two non-invasive monitoring techniques: Doppler ultrasonography-derived Renal Resistive Index (RRI) and Near-Infrared Spectroscopy (NIRS)-derived renal regional oxygen saturation (rSO₂). Measurements will be obtained at predefined perioperative time points, including after induction of anesthesia, during pneumoperitoneum, before extubation, and during the early postoperative period. Perioperative changes in renal perfusion parameters will be analyzed and correlated with clinical variables such as intra-abdominal pressure, pneumoperitoneum duration, hemodynamic parameters, fluid administration, urine output, and postoperative renal function. The study also aims to investigate the relationship between intraoperative renal perfusion changes and the development of postoperative acute kidney injury. The findings may contribute to improved perioperative monitoring and optimization of renal perfusion during minimally invasive abdominal surgery.

Conditions

Renal Perfusion; Minimally Invasive Surgical Procedures; Acute Kidney Injury

Keywords

Kidney Perfusion,Renal Resistive Index,Near-Infrared Spectroscopy,Acute Kidney Injury,Laparoscopic Surgery

Outcome Measures

Primary Outcomes (2)

• Change in Renal Regional Oxygen Saturation Measured by NIRS

  Renal regional oxygen saturation (rSO₂) will be measured bilaterally using Near-Infrared Spectroscopy (NIRS). NIRS values will be recorded at predefined perioperative time points.

  after endotracheal intubation, immediately before extubation, and 1 hour after extubation

• Change in Renal Resistive Index

  Renal Resistive Index (RRI) measured by Doppler ultrasonography at predefined perioperative time points. RRI will be calculated from peak systolic velocity and end-diastolic velocity obtained from renal interlobar or arcuate arteries.

  after endotracheal intubation, immediately before extubation, and 1 hour after extubation

Secondary Outcomes (1)

• Relationship Between Renal Resistive Index and Renal Regional Oxygen Saturation

  after endotracheal intubation, immediately before extubation, and 1 hour after extubation

Study Arms (1)

Elective Minimally Invasive Abdominal Surgery Patients

Adult patients aged 18 to 80 years undergoing elective minimally invasive abdominal surgery under general anesthesia. Renal perfusion will be assessed perioperatively and postoperatively(postoperative 1. hour) using Doppler ultrasonography-derived Renal Resistive Index (RRI) and Near-Infrared Spectroscopy (NIRS)-derived regional renal oxygen saturation (rSO₂). Measurements will be performed at predefined perioperative time points and correlated with intraoperative variables, postoperative renal function, and the occurrence of acute kidney injury.

Eligibility Criteria

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

Study Population

Adult patients aged 18-80 years with ASA physical status I-III undergoing elective minimally invasive abdominal surgery at Istanbul University-Cerrahpaşa Faculty of Medicine. Patients will be prospectively evaluated for perioperative renal perfusion using Doppler ultrasonography and Near-Infrared Spectroscopy (NIRS).

You may qualify if:

• Patients aged 18 to 80 years
• Patients with ASA physical status I, II, or III
• Patients undergoing elective minimally invasive abdominal surgery for any reason
• Patients whose expected surgical duration is longer than 1 hour

You may not qualify if:

• Body mass index greater than 35 kg/m²
• Severe respiratory system disease
• Severe heart failure, NYHA class III-IV
• Presence of a cardiac pacemaker or cardiac defibrillator implant
• Progressive neuromuscular disease
• High intra-abdominal pressure
• Sudden deterioration of general condition
• Incomplete clinical or laboratory data
• Refusal to participate in the study
• Conversion to open surgery

Sponsors & Collaborators

• Istanbul University - Cerrahpasa: lead

Study Sites (1)

Istanbul University Cerrahpaşa Faculty of Medicine

Istanbul, 34320, Turkey (Türkiye)

RECRUITING

MeSH Terms

Conditions

Acute Kidney Injury

Condition Hierarchy (Ancestors)

Renal Insufficiency; Kidney Diseases; Urologic Diseases; Female Urogenital Diseases; Female Urogenital Diseases and Pregnancy Complications; Urogenital Diseases; Male Urogenital Diseases

Central Study Contacts

Lyudmila MARTYNENKO AYDOGDU, M.D.

CONTACT

+90 5300613611; lyudmila.lylyly1@gmail.com

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: M.D.

Study Record Dates

• First Submitted: June 3, 2026
• First Posted: June 9, 2026
• Study Start: January 7, 2026
• Primary Completion (Estimated): January 7, 2027
• Study Completion (Estimated): January 7, 2027
• Last Updated: June 9, 2026

Record last verified: 2026-06

Data Sharing

• IPD Sharing: Will not share

Locations

TU (1)