Hemoglobin Trends as a Predictor of Outcomes in Critically Ill Patients (The TRENT-ICU Study)

August 10, 2026 updated by: Jose J Zaragoza, MD MSc, Hospital H+ Queretaro

The TRENT-ICU Study (Transfusion Threshold Based on Hemoglobin Trends): Hemoglobin Drop Rate as a Predictor of Adverse Clinical Outcomes in Critically Ill Patients

The goal of this observational study is to evaluate if early absolute hemoglobin decline (during the first 24 hours of admission) can predict prolonged intensive care unit stay (8 days or more) and in-hospital mortality in critically ill adult patients.

The main questions it aims to answer are:

Does absolute hemoglobin decline during the first 24 hours of admission independently predict prolonged intensive care unit stay in critically ill adult patients?

Does absolute hemoglobin decline during the first 24 hours of admission independently predict in-hospital mortality in critically ill adult patients?

Participants will:

Have their routine clinical and laboratory data reviewed retrospectively from their electronic health records (including baseline hemoglobin and a second hemoglobin determination approximately 24 hours after admission). No additional interventions or extra blood draws will be performed beyond routine clinical care.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Study Type

Observational

Enrollment (Actual)

128

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • Mexico
    • Querétaro
      • Querétaro City, Querétaro, Mexico, 76000
        • Hospital H+ Querétaro, Santiago de Querétaro, Querétaro

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Sampling Method

Non-Probability Sample

Study Population

dult patients admitted to the Intensive Care Unit at Hospital H+ Querétaro, Mexico, between January 2024 and January 2026, who required an ICU stay of more than 48 hours and had serial hemoglobin measurements during routine medical care.

Description

Inclusion Criteria:

  • Adult patients (aged 18 years or older) admitted to the Intensive Care Unit (ICU) between January 2024 and January 2026.
  • ICU length of stay greater than 48 hours.
  • At least two hemoglobin determinations obtained with an interval of approximately 24 hours apart during routine medical care.

Exclusion Criteria:

  • Massive bleeding upon ICU admission.
  • Massive transfusion protocol activation.
  • Pregnancy.
  • Hemoglobinopathies.
  • Active hemolytic anemia.
  • Medical records with insufficient information for analysis.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

Cohorts and Interventions

Group / Cohort
Intervention / Treatment
Critically Ill Adult Patients
Adult patients admitted to the intensive care unit with an ICU stay of more than 48 hours and at least two hemoglobin determinations obtained approximately 24 hours apart during routine care.
Other: Early Absolute Hemoglobin Decline
Measurement of the absolute difference in hemoglobin concentration (g/dL) between baseline ICU admission and approximately 24 hours post-admission. Data was collected retrospectively from electronic health records.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Prolonged Intensive Care Unit Stay
Time Frame: From ICU admission up to 28 days
Incidence of prolonged intensive care unit (ICU) length of stay, defined a priori as an ICU stay equal to or greater than 8 days.
From ICU admission up to 28 days

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
In-Hospital Mortality
Time Frame: From ICU admission up to 30 days
Incidence of all-cause mortality recorded at hospital discharge.
From ICU admission up to 30 days

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Hospital H+ Queretaro

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

July 31, 2026

Primary Completion (Actual)

July 31, 2026

Study Completion (Actual)

July 31, 2026

Study Registration Dates

First Submitted

August 3, 2026

First Submitted That Met QC Criteria

August 10, 2026

First Posted (Actual)

August 12, 2026

Study Record Updates

Last Update Posted (Actual)

August 12, 2026

Last Update Submitted That Met QC Criteria

August 10, 2026

Last Verified

August 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • CEI2026-30/04/V1

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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