Intrathecal MoRphine Versus Transabdominal Plane Block (TAP) Block for AnalGesic Management in Elective Caesarean Section (MIRAGE)

Intrathecal MoRphine Versus Transabdominal Plane Block (TAP) Block for AnalGesic Management in Elective Caesarean Section Performed Under Neuraxial Anesthesia. A Monocentric Pilot Randomized Controlled Trial

The goal of this randomized controlled clinical trial is to determine if low-dose intrathecal morphine is superior to a Transversus Abdominis Plane (TAP) block with ropivacaine and clonidine for postoperative analgesia in women aged 18 years or older undergoing elective cesarean section under neuraxial anesthesia.

The main questions it aims to answer are:

• Is intrathecal morphine more effective than TAP block in reducing postoperative somatic pain at rest?
• Does intrathecal morphine differ from TAP block in terms of adverse events, pain during mobilization, visceral pain, rescue analgesic use, maternal satisfaction, and newborn wellbeing?

Researchers will compare the intrathecal morphine (ITM) group to the TAP block (TB) group to see if ITM provides superior analgesia and improved secondary outcomes.

Participants will:

• Undergo spinal anesthesia with hyperbaric bupivacaine and sufentanil
• add 30 μg intrathecal morphine (only ITM group)
• receive bilateral ultrasound-guided TAP block with 20 ml ropivacaine 0.25% and 75 μg clonidine per side (only TB group)
• receive standardized postoperative analgesia with paracetamol, ibuprofen, and tramadol as needed
• be monitored postoperatively for pain (somatic and visceral, at rest and with movement), adverse events, mobilization, maternal satisfaction, and newborn outcomes at regular intervals for 24 hours

This is a single-center, pilot, single-blind trial involving 100 participants (50 per group).

Study Overview

• Status: Not yet recruiting
• Conditions: Pregnancy; Cesarean Section; Neuroaxial Analgesia Procedures
• Intervention / Treatment: Drug: Intrathecal Morphine; Drug: TAP Block

Detailed Description

It is a monocentric randomized single-blind controlled pilot trial, wherein the patient and the biostatistics will be unaware about assigned treatment group, whereas the study investigators and site staff will be aware of the treatment group.

The trial consists in two treatment arms:

• Transabdominal Plane Block (TAP) block with ropivacaine and clonidine performed at the end of surgery (this will be performed in the operating room, behind a drape, so that the patient is unaware of the study arm)
• Addition of low doses of morphine to the other drugs administered during the performance of spinal anaesthesia Women aged 18 years and older, with indication for elective caesarean section, gestational age 34 weeks and older, admitted to the Giannina Gaslini Institute will participate in this study.

After an adequate anamnesis, the confirmation of the presence of all the inclusion criteria and the absence of the exclusion criteria and the acquisition of the informed consent, the subjects will be assigned to the treatment arm with a computer-generated random number sequence. The investigator/designated study personnel will administer the treatment as per the randomization codes.

Clinical and instrumental parameters (such as pain, vital signs, the possible occurrence of symptoms such as nausea, vomiting, itching) will then be evaluated during the caesarean section and at 12, 18, 24 hours on the day of the caesarean section (possibly at 6 a.m. on the following day in the case of a caesarean section after 12 noon) and 24 hours after the operation, and the use of analgesics as needed in the case of uncontrolled pain (previously prescribed by the anaesthetist). The baby's well-being will be assessed at birth and, 24 hours after the operation, a questionnaire will be submitted to the patient, to assess her satisfaction.

The study intervention will be performed in the operating room of Departmental Unit of Obstetrics and Gyne-cology of IRCSS Giannina Gaslini Institute. The follow up will be performed in the inpatient ward of the same Departmental Unit.

For the purpose of this trial, the end of study (EOS) is defined as the last visit of last patient.

A total number of 100 participants, a sample size of 50 per group, will be recruited during the study.

• Study Type: Interventional
• Enrollment (Estimated): 100
• Phase: Phase 4

Contacts and Locations

• Study Contact: Name: Gabriele G De Tonetti; Phone Number: 0039 3387857400; Email: gabrieledetonetti@gaslini.org

Study Locations

• Italy
  • GE
    • Genova, GE, Italy, 16147
      • Istituto Giannina Gaslini
      • Contact: Gabriele G De Tonetti; Phone Number: 0039 3387857400; Email: gabrieledetonetti@gaslini.org

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Planned for elective Cesarean Section (CS)
• Scheduled for spinal anesthesia
• Gestational age > 34 weeks
• Age 18 years or above
• Ability to read and understand the information sheet and to sign and date the consent form

Exclusion Criteria:

• American Society of Anesthesiologists (ASA) classification >2
• Body Mass Index (BMI) ≥ 40 kg/m2
• Weight < 50 kg
• Height < 150 cm or ≥ 180 cm
• Complicated Pregnancy (abnormal placentation, preeclampsia or others)
• Women with opioid use disorder
• Contraindication to spinal anesthesia (clotting disorder, local infection, spinal malformation, elevated intracranial pressure)
• Contraindication to Transabdominal Plane Block (TAP) block (skin infection, abdominal wall muscle defects)
• Allergy/contraindication to any medication used in the study
• Previous median abdominal incision
• Emergency or unplanned CS

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Intrathecal morphine as adjuvant (ITM group); All patients will undergo spinal anesthesia at the L3 to L4 or L4 to L5 interspace with hyperbaric bupivacaine 0.5% (10 mg) and 3 μg of sufentanil, Intrathecal morphine as adjuvant (ITM) group adds morphine 30 μg.	Drug: Intrathecal Morphine; The anesthetist in charge performs spinal anesthesia using a 25-gauge pencil point needle in the sitting position at the L3 to L4 or L4 to L5 interspace. After skin disinfection with 2% alcoholic chlorhexidine solution and skin anesthesia with 2 ml of lidocaine 2%, all patients receive spinal anesthesia with a solution of 2 ml hyper-baric bupivacaine 0.5% (10 mg) and 3 μg of sufentanil while, ITM group adds morphine 30 μg. The patient is not informed about the drugs used in spinal anesthesia.
Active Comparator: TAP block with ropivacaine and clonidine (TB); At the end of surgery, in the TB group a bilateral ultrasound-guided Transabdominal Plane Block (TAP) block is performed with 20 ml of ropivacaine 0.25% and 75 μg of clonidine each site using a non-Insulated Echogenic Needle 22 Gauge (80 mm). The TAP block will be performed behind the operating drapes so the patient remains blind to the study arm.	Drug: TAP Block; At the end of surgery, in the TB group a bilateral Transabdominal Plane Block (TAP) block is performed. The anesthetist prepares two sy-ringes with 20 ml each with ropivacaine 0.25% with 75 μg of clonidine. Upon identifying the TAP compart-ment in the lateral abdominal wall (in the midaxillary line between the bony prominences of the subcostal margin and the iliac crest) with the linear high-frequency ultrasound probe, we penetrate the skin with the block needle using an in-plane technique. Upon entering the plane between the internal oblique and the transversus abdominis muscles, and after negative aspiration of blood, the local anesthetic is slowly injected. The TAP compartment begins to separate, hydrodissect, or "unzip" as the local anesthetic is injected, pushing the transversus abdominis muscle down. An injection of 20 ml of the prepared solution is injected for each side. The TAP block is performed behind the operating drape.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
The primary object is to determine if, in elective cesarean section performed under neuraxial anesthesia, low dose morphine as intrathecal adjuvant is superior to TAP Block using ropivacaine and clonidine in terms of postoperative pain	The primary endpoint of this trial is the determination of how many times somatic Visual Analogue Scale (or VAS, from worst 0 to best 10) at rest is 6 or more in the different evaluations at 12 AM, 6 PM, 00 AM (or at 6 PM, 00 AM and 6 AM if the cesarean section is performed after 12 AM) and at 24 hours from the spinal anesthesia.	From enrollment to 24 hours after spinal anesthesia

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Evaluation of somatic pain with movement	STATISTICAL DIFFERENCE OF MEAN AND STANDARD DEVIATION (SD) OF Somatic Pain (with visual analogue scale 0 worst-10 best)	From enrollment to 24 hours after spinal anesthesia
Evaluation of visceral pain at rest and on movement	STATISTICAL DIFFERENCE OF MEAN AND STANDARD DEVIATION (SD) of Visceral Pain (with visual analogue scale 0 worst-10 best)	From enrollment to 24 hours after spinal anesthesia
Evaluation of rescue dose therapy consumption in mg	STATISTICAL DIFFERENCE OF MEAN AND STANDARD DEVIATION OF Time to First Rescue Dose (min)	From enrollment to 24 hours after spinal anesthesia
Incidence of adverse events	Measure the incidence of Nausea (Internal Gaslini scale, 0 best - 4 worst), incidence of pruritus (Internal Gaslini scale, 0 best - 3 worst), incidence of Urinary Retention (occurrence and need for catheterization), incidence of Hypothension (systolic arterial pressure <100 mmHg or <80% of baseline, total mg of ephedrine) and Bradycardia (heart rate <50 bpm)	From enrollment to 24 hours after spinal anesthesia
Evaluate the quality of recovery after surgery for cesarean delivery	MEAN AND STANDARD DEVIATION OF Obstetric Quality-of-Recovery score ObsQoR-11 (worst 0-best110 pts)	From enrollment to 24 hours after spinal anesthesia
Incidence of Hypotension	Measurement thorugh systolic arterial pressure <100 mmHg or <80% of baseline, total mg of ephedrine and evaluation of Bradycardia as heart rate <50 bpm	From enrollment to 24 hours after spinal anesthesia

Collaborators and Investigators

• Sponsor: Istituto Giannina Gaslini

Study record dates

Study Major Dates

• Study Start (Estimated): March 1, 2026
• Primary Completion (Estimated): March 1, 2027
• Study Completion (Estimated): March 2, 2027

Study Registration Dates

• First Submitted: August 7, 2025
• First Submitted That Met QC Criteria: January 22, 2026
• First Posted (Actual): January 30, 2026

Study Record Updates

• Last Update Posted (Actual): January 30, 2026
• Last Update Submitted That Met QC Criteria: January 22, 2026
• Last Verified: January 1, 2026

More Information

Terms related to this study

• Keywords: cesarean section; morphine; TAP block; neuraxial anesthesia
• Other Study ID Numbers: EU CT 2024-513150-29-00

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No