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).
Planned for elective Cesarean Section (CS)
Scheduled for spinal anesthesia
Gestational age > 34 weeks
Age 18 years or above
American Society of Anesthesiologists (ASA) classification >2
Body Mass Index (BMI) ≥ 40 kg/m2
Weight < 50 kg
Height < 150 cm or ≥ 180 cm