Clinical Validation of a Blood Loss Monitoring System

NCT07617428 | Enrolling By Invitation

• 1 other identifier: 2025A-987
• Study Type: observational
• Target: 120
• Locations: 1 country
• Sites: 3

Brief Summary

This observational study aims to evaluate the practicality of a novel multifunctional intraoperative blood loss monitoring system in real-world surgical settings. The primary questions it seeks to address are: Using the direct measurement method as the reference standard, what is the magnitude of measurement error of the monitoring system, and does it tend to overestimate or underestimate blood loss? Does the monitoring system demonstrate superior accuracy compared with visual estimation, the gravimetric method, and the hemoglobin concentration-based method? During surgery, intraoperative blood loss will be measured simultaneously using five approaches: the novel multifunctional monitoring system, the direct measurement method, visual estimation, the gravimetric method, and the hemoglobin concentration method. These measurements will be conducted without interfering with the surgical procedure.

Conditions

Intraoperative Blood Loss

Keywords

blood loss; Clinical Validation; Monitoring Equipment

Outcome Measures

Primary Outcomes (1)

• Absolute error of the automatic intraoperative blood loss monitor compared with the direct measurement method

  Absolute error is defined as the numerical difference between intraoperative blood loss measured by the automatic intraoperative blood loss monitor and intraoperative blood loss measured by the direct measurement method. A positive value indicates that the monitor overestimates blood loss compared with the direct measurement method, whereas a negative value indicates underestimation. Unit of Measure: Milliliters (mL)

  At the end of surgery

Secondary Outcomes (7)

• Percentage error of the automatic intraoperative blood loss monitor compared with the direct measurement method

  At the end of surgery

• Absolute error of visual estimation compared with the direct measurement method

  At the end of surgery

• Absolute error of the gravimetric method compared with the direct measurement method

  At the end of surgery

• Absolute error of the hemoglobin concentration-based method compared with the direct measurement method

  24 hours after surgery

• Intraclass correlation coefficient between the automatic intraoperative blood loss monitor and the direct measurement method

  At the end of surgery

Study Arms (1)

Self-controlled

This study includes a single self-controlled cohort of patients undergoing urological and general surgical procedures. All participants will undergo simultaneous intraoperative blood loss assessment using five different methods within the same surgical procedure: a novel multifunctional intraoperative blood loss monitoring system, the direct measurement method (reference standard), visual estimation, the gravimetric method, and the hemoglobin concentration-based method. No intervention is applied in this observational study. All measurements are performed according to a predefined protocol and do not interfere with the standard surgical workflow. The purpose of this design is to enable within-subject comparison of measurement accuracy across different methods under identical clinical conditions.

Eligibility Criteria

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

Study Population

The study population will be recruited from adult patients undergoing elective urological and general surgical procedures at two tertiary hospitals in China, including Lanzhou University Second Hospital and Lanzhou University First Hospital. Participants will be selected from routine clinical practice settings where intraoperative blood loss monitoring is required. This population represents adult surgical patients managed under standard perioperative care, providing a real-world clinical context for evaluating intraoperative blood loss measurement methods.

You may qualify if:

• Patients undergoing elective urological or general surgical procedures
• Age 18 years or older
• Preoperative hemoglobin concentration available
• Intraoperative blood loss assessment required during surgery

You may not qualify if:

• Patients with incomplete intraoperative blood loss measurement data,
• Severe hemolysis or other conditions that may affect hemoglobin measurement
• Emergency surgery
• Intraoperative blood loss assessment required during surgery 24 hours after surgery
• Refusal to participate, when applicable

Sponsors & Collaborators

• Lanzhou University Second Hospital: lead
• Lanzhou University First Hospital: collaborator

Study Sites (3)

Gansu Provincial People's Hospital

Lanzhou, Gansu, 730030, China

Location

Lanzhou University Frist Hospital

Lanzhou, Gansu, 730030, China

Location

Lanzhou University Second Hospital

Lanzhou, Gansu, 730030, China

Location

MeSH Terms

Conditions

Hemorrhage

Condition Hierarchy (Ancestors)

Pathologic Processes; Pathological Conditions, Signs and Symptoms

Study Design

• Study Type: observational
• Observational Model: CASE ONLY
• Time Perspective: PROSPECTIVE
• Target Duration: 1 Day
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Professor; Chief Physician

Study Record Dates

• First Submitted: May 5, 2026
• First Posted: June 1, 2026
• Study Start: September 10, 2025
• Primary Completion: May 30, 2026
• Study Completion: May 30, 2026
• Last Updated: June 3, 2026

Record last verified: 2026-04

Locations

CN (3)