Population Pharmacokinetics of Remifentanil in Low-Weight Critically Ill Patients

NCT07301970 | Recruiting

• 1 other identifier: 2025-007-01K
• Study Type: observational
• Target: 45
• Locations: 1 country
• Sites: 1

Brief Summary

The goal of this prospective clinical study is to learn about the population pharmacokinetics (PopPK), safety, and efficacy of remifentanil in low-body-weight patients in the Intensive Care Unit (ICU) who require mechanical ventilation. The main questions it aims to answer are:

1. 1.What are the pharmacokinetic characteristics of remifentanil in low-weight ICU patients?
2. 2.How does remifentanil (and concurrent propofol use) affect hemodynamic stability (such as blood pressure) and sedation efficacy in this population?

Conditions

Critical Illness; Pain

Outcome Measures

Primary Outcomes (1)

• Plasma Concentration of Remifentanil

  Peripheral arterial blood samples (1mL each) drawn from an existing indwelling arterial blood pressure (ABP) catheter will be collected to determine the plasma concentration of remifentanil (unit: ng/mL). A sparse and opportunistic sampling strategy is employed to capture the full pharmacokinetic profile. Sampling points typically include: 1. Absorption/Distribution Phase: Approximately 2 samples within the first 2 hours of administration; 2. Maintenance Phase: Samples collected during steady-state infusion, and following dose adjustments to capture the new steady state (typically after re-equilibration); 3. Elimination Phase: Approximately 3 samples within 2 hours after the end of infusion.

  From the start of remifentanil administration, through the maintenance infusion phase, up to 2 hours after the end of infusion.

Secondary Outcomes (3)

• Mean Arterial Pressure (MAP)

  From baseline throughout the duration of drug infusion (up to approximately 48 hours).

• Plasma Concentration of Propofol

  From the start of its administration, through the maintenance infusion phase, up to 2 hours after the end of infusion.

• Heart Rate

  From baseline throughout the duration of drug infusion (up to approximately 48 hours).

Study Arms (2)

Low-weight group

BMI \< 18.5

Drug: Remifentanil

Normal-weight group

18.5 ≤ BMI\< 24

Drug: Remifentanil

Interventions

Remifentanil DRUG

Patients receive remifentanil for analgesia and sedation during mechanical ventilation. The administration follows standard ICU clinical practice, typically initiated at a continuous infusion rate (e.g., approximately 0.18 mg/h or weight-based equivalent) and titrated based on patient response.

Low-weight group; Normal-weight group

Eligibility Criteria

• Sex: all
• Healthy Volunteers: No
• Age Groups: Child (0-17), Adult (18-64), Older Adult (65+)
• Sampling Method: Probability Sample

Study Population

Adult patients admitted to the Intensive Care Unit (ICU) requiring invasive mechanical ventilation who receive remifentanil for analgesia and sedation. The study population comprises two cohorts stratified by Body Mass Index (BMI): a low-body-weight group (BMI \< 18.5 kg/m²) and a normal-body-weight control group (18.5 kg/m² ≤ BMI \< 24 kg/m²).

You may qualify if:

• Age: ≥18 years old, regardless of sex;
• Normal weight: 18.5 kg/m² ≤ Body Mass Index (BMI) \< 24 kg/m² or Low weight: BMI \< 18.5 kg/m²;
• Admitted to the intensive care unit (ICU);
• Required invasive mechanical ventilation for more than 10 hours;
• The subject or their legal guardian has fully understood the potential risks and benefits of participating in this study and has signed the informed consent form.

You may not qualify if:

• Pregnant women;
• Presence of severe respiratory impairment or respiratory depression during the screening period;
• Known hypersensitivity to remifentanil or any of the excipients;
• Meeting other contraindications for opioid use

Sponsors & Collaborators

• Fudan University: lead

Study Sites (1)

Shanghai Minhang Central Hospital

Shanghai, China

RECRUITING

Biospecimen

Retention: SAMPLES WITHOUT DNA

plasma

MeSH Terms

Conditions

Critical Illness; Pain

Interventions

Remifentanil

Condition Hierarchy (Ancestors)

Disease Attributes; Pathologic Processes; Pathological Conditions, Signs and Symptoms; Neurologic Manifestations; Signs and Symptoms

Intervention Hierarchy (Ancestors)

Propionates; Acids, Acyclic; Carboxylic Acids; Organic Chemicals; Piperidines; Heterocyclic Compounds, 1-Ring; Heterocyclic Compounds

Study Officials

• Xiang Li

  Shanghai Minhang Central Hospital

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Xiang Li

CONTACT

+86 18918169826; xiangli0159@hotmail.com

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Target Duration: 7 Days
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Director

Study Record Dates

• First Submitted: November 29, 2025
• First Posted: December 24, 2025
• Study Start: September 22, 2025
• Primary Completion (Estimated): June 30, 2026
• Study Completion (Estimated): November 30, 2026
• Last Updated: December 24, 2025

Record last verified: 2025-09

Data Sharing

• IPD Sharing: Will not share

Locations

CN (1)