Effect of Postural Change on Hemoglobin Level in Patients on the Intensive Care Unit

Monitoring hemoglobin levels (Hb) is important to identify anemia in hospitalized patients. Changes in posture and mobilization efforts, as demonstrated by previous research, can lead to significant shifts in Hb concentrations. This phenomenon has not been studied in ICU patients.

This study aims to investigate whether postural changes and mobilisation affect Hb in ICU patients. We hypothesize that significant Hb shifts may occur, potentially leading to misinterpretations of anemia and unnecessary diagnostic and therapeutic workup. Understanding this impact can guide clinical practice and prevent unwarranted interventions.

Study Overview

• Status: Not yet recruiting
• Conditions: Anemia
• Intervention / Treatment: Procedure: Postural change from supine to sitting; Procedure: Mobilization to a chair

Detailed Description

Rationale:

Monitoring hemoglobin levels (Hb) is important to identify anemia in hospitalized patients. Changes in posture and mobilization efforts, as demonstrated by previous research, can lead to significant shifts in Hb concentrations. Low Hb levels due to these shifts are termed 'postural pseudoanemia'.

This phenomenon has not been studied in ICU patients. Many factors may affect Hb concentrations in ICU patients, including plasma volume shifts, bleeding, repeated phlebotomies, hemolysis, bone marrow suppression and functional iron deficiency. When this leads to significant anemia, patients may be treated with red blood cell transfusions. However, blood transfusions have been associated with adverse reactions and should only be performed for appropriate indications. If postural pseudoanemia occurs in ICU patients this could lead to patient harm through inadvertent investigations and red blood cell transfusions. The occurrence of postural pseudoanemia in ICU patients may differ from previous studies because ICU patients are more frequently immobilized for more prolonged periods.

This study aims to investigate whether postural changes affect Hb in ICU patients. We hypothesize that significant Hb shifts may occur, potentially leading to misinterpretations of anemia and unnecessary diagnostic and therapeutic workup. Understanding this impact can guide clinical practice and prevent unwarranted interventions.

Objective:

Main objective: To assess Hb levels in ICU patients upon a change in posture from supine to upright and following mobilization to a chair.

Secondary objectives:

To seek correlations between hemoglobin shifts and changes in serum albumin concentrations upon a change in posture from supine to sitting and following mobilization to a chair.

To seek correlations between hemoglobin shifts and changes in serum uric acid concentrations upon a change in posture from supine to sitting and following mobilization to a chair.

To seek correlations between hemoglobin shifts and levels of CRP and ESR upon a change in posture from supine to sitting and following mobilization to a chair.

To compare hemoglobin concentrations following > 6 hours in supine position at 24 hours with pre-intervention levels for patients remaining in the ICU.

Any other changes seen in the lab measurements or vital parameters upon a change in posture?

Study design:

Prospective uncontrolled interventional study.

Study population:

Patients > 18 years old, admitted to the intensive care unit.

Intervention:

All patients will undergo a change in posture from supine to upright, followed by mobilization to a chair.

Main study parameters/endpoints:

Relative percentage change in Hb.

• Study Type: Interventional
• Enrollment (Estimated): 24
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Alfred L van Steveninck, M.D., Ph.D.; Phone Number: +31570535346; Email: f.steveninckvan@dz.nl
• Study Contact Backup: Name: Huub LA van den Oever, M.D.; Phone Number: +31570535346; Email: h.vandenoever@dz.nl

Study Locations

• Netherlands
  • Deventer, Netherlands, 7416SE
    • Deventer Hospital
    • Contact: Alfred L van Steveninck, M.D., Ph.D.; Phone Number: +31570535346; Email: f.steveninckvan@dz.nl
    • Contact: Huub LA van den Oever, M.D.; Phone Number: +31570535346; Email: h.vandenoever@dz.nl

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Age over 18 years, of any gender and ethnic background
• Admitted to the intensive care unit
• Able to give informed consent
• Patients with an arterial line as part of their treatment plan.
• Patients able to remain seated in chair for at least 30 minutes
• Patients able to remain supine overnight for at least 6 hours

Exclusion Criteria:

• Delirium or inability to give informed consent
• Inability to understand written information in Dutch
• Patients on artificial ventilation
• Orotracheally intubated patients (spontaneous breathing through a tracheostomy cannula is allowed)
• Patients treated with noradrenaline > 0.05 ug/kg/min
• Patients treated with argipressin
• Patients who received a blood transfusion within 24 hours before measurements
• Patients who received > 3 L of fluids within 24 hours before measurements
• Patients who received > 500 ml of iv fluids within 4 hours of measurements
• Severe restlessness or inability to remain supine for 6 hours before initial blood sampling
• Patients being treated with diuretics
• Patients admitted with:
• Decompensated right heart failure
• Pulmonary hypertension
• Pulmonary embolism
• Active bleeding or risk of >100 ml blood loss
• Hematological disorder/malignancy

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Diagnostic
• Allocation: N/A
• Interventional Model: Sequential Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Hb in different positions; Hemoglobin concentration after sitting in bed (passively) for >30 min, and after mobilization to a chair for >30 min	Procedure: Postural change from supine to sitting; Patients go from supine to sitting position in bed (passive); Procedure: Mobilization to a chair; Patients go from the bed to sitting in a chair (active)

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Hemoglobin	Hemoglobin concentration	3 hours

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Albumin	Albumin concentration	3 hours

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Uric acid	Uric acid concentration	3 hours

Collaborators and Investigators

• Sponsor: Deventer Ziekenhuis
• Investigators: Principal Investigator: Alfred L van Steveninck, M.D., Ph.D., Deventer Ziekenhuis

Study record dates

Study Major Dates

• Study Start (Estimated): June 17, 2024
• Primary Completion (Estimated): October 30, 2024
• Study Completion (Estimated): October 30, 2024

Study Registration Dates

• First Submitted: May 21, 2024
• First Submitted That Met QC Criteria: May 30, 2024
• First Posted (Actual): June 3, 2024

Study Record Updates

• Last Update Posted (Actual): June 3, 2024
• Last Update Submitted That Met QC Criteria: May 30, 2024
• Last Verified: May 1, 2024

More Information

Terms related to this study

• Keywords: Blood composition; Circulatory physiology
• Other Study ID Numbers: NL86966

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Data can be obtained from the principal investigator upon request.
• IPD Sharing Time Frame: After preparation of the manuscript.
• IPD Sharing Access Criteria: A written request must be sent to the principal investigator.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP; ICF; ANALYTIC_CODE; CSR

Drug and device information, study documents

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