Clinical Impact of Different Crystalloid Solution on Early Biomarkers of Kidney Injury After Lumbar Fusion Surgery in Elderly Patients

This study aims to compare the effects of sodium acetate Ringer's solution versus sodium lactate Ringer's solution on early postoperative renal function indicators, renal injury biomarkers, and acute kidney injury (AKI) in elderly patients undergoing lumbar fusion surgery.

Study Overview

• Status: Completed
• Conditions: Biomarkers; Acute Kidney Injury; Elderly Patients; Lumbar Fusion Surgery; Sodium Acetate Ringer's Solution; Sodium Lactate Ringer's Solution
• Intervention / Treatment: Other: Sodium Acetate Ringer's Solution (Group A); Other: Sodium Lactate Ringer's Solution (Group B)

Detailed Description

This is a single-center prospective randomized comparative study. A total of 174 elderly patients scheduled for elective lumbar fusion surgery under general anesthesia will be randomly assigned in a 1:1 ratio to receive either sodium acetate Ringer's solution (Group A, n = 87) or sodium lactate Ringer's solution (Group B, n = 87) for intraoperative fluid management.

Conventional renal function indicators, including serum creatinine (SCr) and estimated glomerular filtration rate (eGFR), as well as early renal injury biomarkers, including lactate, urinary neutrophil gelatinase-associated lipocalin (uNGAL), urinary kidney injury molecule-1 (uKIM-1), and serum cystatin C (sCysC), will be compared between the two groups. Postoperative AKI will be assessed according to the KDIGO serum creatinine criteria.

The study will evaluate whether the choice of intraoperative crystalloid solution influences early postoperative renal stress in this high-risk population.

• Study Type: Interventional
• Enrollment (Actual): 174
• Phase: Not Applicable

Contacts and Locations

Study Locations

• China
  • Foshan, China, 528300
    • Shunde Hospital of Guangzhou University of Chinese Medicine

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• age 65-80 years
• planned lumbar fusion surgery
• ability to provide informed consent

Exclusion Criteria:

• severe pre-existing cardiac, hepatic, or renal dysfunction
• known allergy to study fluids
• use of nephrotoxic drugs within 24 h before surgery
• emergency surgery
• severe psychiatric disorders or impaired consciousness
• intraoperative blood loss >1000 mL or requirement for blood transfusion
• presence of malignancy

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Other
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Other: Sodium Acetate Ringer's Solution (Group A); Patients in this arm receive sodium acetate Ringer's solution as the intraoperative crystalloid fluid for management during elective lumbar fusion surgery under general anesthesia. The fluid administration protocol is standardized as follows: (1) initial volume loading of 5-10 mL/kg within 30 minutes after anesthesia induction; (2) maintenance infusion at 5-7 mL/kg/h; and (3) replacement of blood loss at a crystalloid-to-blood loss ratio of approximately 3:1. Infusion rates are adjusted based on stroke volume variation and hemodynamic parameters. The assigned crystalloid solution is also used as the carrier fluid for any required vasoactive medications. This arm is compared against a control arm receiving sodium lactate Ringer's solution. The target population consists of elderly patients (aged 65-80 years) scheduled for lumbar fusion surgery.	Other: Sodium Acetate Ringer's Solution (Group A); Patients in this arm receive sodium acetate Ringer's solution as the intraoperative crystalloid fluid for management during elective lumbar fusion surgery under general anesthesia. The fluid administration protocol is standardized as follows: (1) initial volume loading of 5-10 mL/kg within 30 minutes after anesthesia induction; (2) maintenance infusion at 5-7 mL/kg/h; and (3) replacement of blood loss at a crystalloid-to-blood loss ratio of approximately 3:1. Infusion rates are adjusted based on stroke volume variation and hemodynamic parameters. The assigned crystalloid solution is also used as the carrier fluid for any required vasoactive medications. This arm is compared against a control arm receiving sodium lactate Ringer's solution. The target population consists of elderly patients (aged 65-80 years) scheduled for lumbar fusion surgery.
Other: Sodium Lactate Ringer's Solution (Group B); Patients in this arm receive sodium lactate Ringer's solution as the intraoperative crystalloid fluid for management during elective lumbar fusion surgery under general anesthesia. The fluid administration protocol is identical to that of the experimental arm: (1) initial volume loading of 5-10 mL/kg within 30 minutes after anesthesia induction; (2) maintenance infusion at 5-7 mL/kg/h; and (3) replacement of blood loss at a crystalloid-to-blood loss ratio of approximately 3:1. Infusion rates are adjusted based on stroke volume variation and hemodynamic parameters. The assigned crystalloid solution is also used as the carrier fluid for any required vasoactive medications. This arm serves as the active comparator against sodium acetate Ringer's solution. The target population consists of elderly patients (aged 65-80 years) scheduled for lumbar fusion surgery	Other: Sodium Lactate Ringer's Solution (Group B); Patients in this arm receive sodium lactate Ringer's solution as the intraoperative crystalloid fluid for management during elective lumbar fusion surgery under general anesthesia. The fluid administration protocol is identical to that of the experimental arm: (1) initial volume loading of 5-10 mL/kg within 30 minutes after anesthesia induction; (2) maintenance infusion at 5-7 mL/kg/h; and (3) replacement of blood loss at a crystalloid-to-blood loss ratio of approximately 3:1. Infusion rates are adjusted based on stroke volume variation and hemodynamic parameters. The assigned crystalloid solution is also used as the carrier fluid for any required vasoactive medications. This arm serves as the active comparator against sodium acetate Ringer's solution. The target population consists of elderly patients (aged 65-80 years) scheduled for lumbar fusion surgery.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Urinary neutrophil gelatinase-associated lipocalin (uNGAL)	Urinary NGAL measured by enzyme-linked immunosorbent assay (ELISA) after standardized sample processing and storage. Higher uNGAL levels indicate greater renal tubular injury.	Postoperative 6, 12, and 24 hours

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Serum creatinine (SCr)	Serum creatinine measured using an automatic biochemical analyzer. Higher SCr indicates worse renal function.	Postoperative 6, 12, and 24 hours
Estimated glomerular filtration rate (eGFR)	eGFR calculated using the CKD-EPI equation based on serum creatinine. Lower eGFR indicates worse renal function.	Postoperative 6, 12, and 24 hours
Urinary kidney injury molecule-1 (uKIM-1)	Urinary KIM-1 measured by enzyme-linked immunosorbent assay (ELISA). Higher uKIM-1 indicates greater renal tubular injury.	Postoperative 6, 12, and 24 hours

Collaborators and Investigators

• Sponsor: Xianping Wu

Study record dates

Study Major Dates

• Study Start (Actual): September 1, 2023
• Primary Completion (Actual): June 19, 2024
• Study Completion (Actual): September 26, 2025

Study Registration Dates

• First Submitted: April 8, 2026
• First Submitted That Met QC Criteria: April 14, 2026
• First Posted (Actual): April 21, 2026

Study Record Updates

• Last Update Posted (Actual): April 21, 2026
• Last Update Submitted That Met QC Criteria: April 14, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Urogenital Diseases; Male Urogenital Diseases; Kidney Diseases; Urologic Diseases; Female Urogenital Diseases; Female Urogenital Diseases and Pregnancy Complications; Renal Insufficiency; Acute Kidney Injury
• Other Study ID Numbers: KY-2023100

Drug and device information, study documents

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