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Study on the Emotional Effects of Morphine, Oxycodone, and Fentanyl Before Surgery in Healthy or Mildly Ill Patients

Verified siteRegistered drugNo placebo
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What is this trial about?

A plain-language summary of the goals, design and what participants do

This clinical trial is focused on understanding the effects of certain medications used before surgery. The study involves patients who are generally healthy or have mild diseases, as determined by a doctor. The medications being studied are three types of opioids: morphine, oxycodone, and fentanyl. These drugs are commonly used to manage pain during surgical procedures. The trial also includes a group receiving a placebo, which is a substance with no active medication.

The main goal of the study is to observe and compare how these medications affect the feelings and emotions of patients before they undergo general anesthesia for surgery. Participants will receive one of the three opioids in specific doses through an injection. The study will monitor how the patients feel after receiving the medication, focusing on their emotional state and any sensations they experience. This will help researchers understand the different effects these opioids have on patients' feelings and emotions.

Throughout the study, participants will be asked to rate their feelings using a simple scale. This includes how good, anxious, or relaxed they feel, as well as any pain they might experience. The study will also look at other effects, such as heart rate changes, to gather more information about how these medications work. By comparing the results from different groups, the study aims to provide insights into the emotional effects of these commonly used opioids in a surgical setting.

The research process

The trial runs in 5 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Joining the study

    Upon joining the study, eligibility is confirmed based on age, health status, and other criteria. Participants must be 18 years or older and classified as ASA1 or ASA2, indicating a healthy status or mild disease without significant limitations.

    Participants must be eligible for the use of the study medications, which include fentanyl, morphine, and oxycodone.

  2. Step 2

    Pre-surgery preparation

    Participants undergo planned day surgery with general anesthesia. This includes various types of surgeries such as orthopedic, minor gastrointestinal, gynecological, hand and foot surgery, and minor vascular procedures.

    Inpatients may undergo planned gynecological and orthopedic surgeries, including procedures like hysterectomy and lumbar herniotomy.

  3. Step 3

    Medication administration

    Participants receive one of three opioids: morphine, oxycodone, or fentanyl, administered intravenously before the induction of general anesthesia.

    The dosages are as follows: morphine at 2.5 mg, 5 mg, or 10 mg; oxycodone at 2.5 mg, 5 mg, or 10 mg; fentanyl at 0.025 mg, 0.05 mg, or 0.1 mg. A placebo group receives saline 0.9%.

  4. Step 4

    Monitoring and assessment

    Participants rate their affective states using a verbal numeric rating scale (NRS 0-10) for feelings such as 'good', 'pain', 'relaxed', and 'anxious' before and after drug administration.

    After receiving the drug, participants indicate when they first feel its effects, and the time is recorded. Further questions about their affective state are asked after a standardized waiting time of 2 minutes.

  5. Step 5

    Data collection

    The study collects data on heart rate variability (HRV) and other objective measures before and after opioid administration.

    Multiple regressions are used to analyze subjective outcomes, considering factors like prior opioid use and depression.

Who can join the trial?

8 criteria

  • Participants must be 18 years of age or older at the time of signing the informed consent.
  • Participants should have a **health status** of **ASA1** or **ASA2**. This means they are either healthy or have mild diseases without serious limitations, as determined by a doctor.
  • The participant must be eligible to use the medications **fentanyl**, **morphine**, and **oxycodone**. A doctor will decide this based on the participant's overall health and any other medications they are taking.
  • Participants should have a **body weight** and **body mass index (BMI)** between 18 and 35 kg/m². BMI is a measure that uses height and weight to estimate body fat.
  • Participants must be able to give signed informed consent, which means they understand and agree to follow the study's rules and requirements.
  • Participants should have good verbal communication skills in Norwegian.
  • Participants should be undergoing planned day surgery with **general anaesthesia**. This includes surgeries like orthopedic, minor gastrointestinal, gynecological, hand and foot surgery, and minor vascular procedures.
  • Participants can also be inpatients undergoing planned gynecological and orthopedic surgeries, such as hysterectomy, laparoscopic ovary removal, lumbar hernia surgery, and other related procedures, including minor gastrointestinal surgery.

Who cannot join the trial?

4 criteria

  • Individuals who are not classified as **ASA1** or **ASA2**. This means they must be generally healthy or have only mild diseases without significant limitations.
  • Individuals who are not eligible for day surgery, which indicates they are not considered overtly healthy by clinical staff.
  • Individuals who are not within the specified age range for the trial.
  • Individuals who belong to a vulnerable population, which means they might need special protection or care.
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Investigated drugs

  • Morphine

    is a medication used to relieve severe pain. In this trial, it is given to participants before surgery to see how it affects their mood and feelings. It is commonly used in hospitals to help manage pain during and after surgery.

  • Oxycodone

    is another pain-relieving medication used in this trial. Like morphine, it is administered before surgery to study its effects on the emotional state of the participants. It is often used to treat moderate to severe pain.

  • Fentanyl

    is a powerful pain medication used in this study. It is given to participants before they undergo surgery to observe its impact on their emotions. Fentanyl is typically used in medical settings for pain management due to its potency.

What is already known about the treatment

  • Morphine

    Morphine is administered intravenously and is commonly used in surgical settings to manage pain before general anesthesia. It is a well-established medication in medical literature and is widely used in clinical practice. The main therapeutic indication for morphine is pain relief. At the molecular level, morphine works by binding to opioid receptors in the brain, which helps to reduce the perception of pain. It is classified as an opioid analgesic.

  • Oxycodone

    Oxycodone is given intravenously and is used to alleviate pain in patients undergoing surgery. It is a recognized medication in the medical field and is frequently referenced in medical literature. The primary therapeutic use of oxycodone is for pain management. It functions by attaching to opioid receptors in the central nervous system, which diminishes the sensation of pain. Oxycodone is categorized as an opioid analgesic.

  • Fentanyl

    Fentanyl is administered intravenously and is utilized in surgical environments to control pain before anesthesia. It is a well-documented medication in medical literature and is extensively used in healthcare. The main therapeutic indication for fentanyl is pain control. It acts by binding to opioid receptors in the brain, leading to a decrease in pain perception. Fentanyl is classified as an opioid analgesic.

Investigated diseases

  • Health Status ASA1

    This classification refers to individuals who are considered healthy, non-smoking, and have no or minimal alcohol use. These individuals do not have any significant medical conditions and are generally in good health. They are typically eligible for day surgery due to their stable health status. The classification is based on a medical history review and physical examination by a healthcare professional. It is used to assess the risk level of patients undergoing surgical procedures.

  • Health Status ASA2

    This classification includes individuals with mild diseases that do not cause significant functional limitations. These individuals may have conditions such as mild asthma or well-controlled diabetes. Despite having these mild conditions, they are generally in good health and can undergo surgical procedures with minimal risk. The classification is determined by a medical professional through a review of the patient's medical history and a physical examination. It helps in assessing the suitability of patients for surgery and anesthesia.

Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2024-518308-37-00Estimated enrolment1 000 patientsSponsorVestre Viken HF

sourced from the EU Clinical Trials Register and site verification

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