Optimal Intrathecal Morphine Dose for Better Post Cesarean Section Analgesia

NCT07560501 | Not Yet Recruiting Phase 4 DMC

• 2 other identifiers: IRC/IOM/D-2026-339NHRC 772-2025
• Study Type: interventional
• Target: 180
• Locations: 0 countries
• Sites: N/A

Brief Summary

Central neuraxial blocks (CNBs) remain the preferred anesthetic technique for cesarean section, with single shot spinal anesthesia (SSSA) being the standard practice at investigator's institute unless contraindicated. SSSA offers reliable intraoperative anesthesia and provides a few hours of postoperative analgesia. Enhanced recovery after cesarean section protocol has recommended the addition of intrathecal (IT) morphine to improve the postoperative quality of the recovery profile. Fentanyl improves the quality of intraoperative analgesia, while morphine significantly prolongs the postoperative pain relief, often lasting up to 24 hours. Routine uterine exteriorization, practiced in all cases at investigator's institute, often results in peritoneal stretching pain during surgery. This visceral pain is managed with 10 mcg intrathecal fentanyl added to hyperbaric bupivacaine. For postoperative pain management, the intrathecal morphine is recommended by many guidelines and studies. Intrathecal morphine dose typically ranges from 50 to 300 mcg. The dose of morphine exceeding 150 mcg are usually associated with prolongation of analgesia with higher incidence of side effects like nausea, vomiting and pruritus. In selected cases, investigator had administered morphine 100-150 mcg and the clinical experience has shown reduced postoperative analgesic requirements and favorable recovery profile, with minimal adverse effects. Despite these promising experiences and extensive literature on IT morphine, their is still lack formal data on the efficacy and safety profile of IT morphine in cesarean section patient. This comparative study will help institute to find the optimum dose of IT morphine with better postoperative analgesia quality with low side effects profile. The finding could serve as a foundation to promote routine use of intrathecal morphine in cesarean section anesthesia at investigator's institute.

Conditions

Post Cesarean Section Pain

Keywords

Analgesia; Cesarean section; Intrathecal Morphine; Postoperative pain

Outcome Measures

Primary Outcomes (1)

• To compare the incidence of postoperative pain after cesarean section with different doses of intrathecal morphine with bupivacaine among the four groups.

  The parturient among study groups receiving different dose of intrathecal morphine with bupivacaine were compared for incidence of postoperative cesarean section pain. The pain is assessed by using Numerical Pain Rating Scale(NRS) ,a 11-point, standardized tool (0-10) in which 0 means "no pain" and 10 means "the worst pain imaginable". The number of parturient with NRS more than 3 will be compared for postoperative pain among the 4 groups.

  NRS score is measured in recovery room for postoperative pain assessment. This time will be recorded as "time zero". Then in postoperative ward, NRS score is measured at 2 hours, 4 hours, 6 hours, 12 hours and 24 hours from 'time zero".

Secondary Outcomes (4)

• To compare the first rescue analgesia demand time among the four groups

  Postoperative period after cesarean delivery till 24 hour

• To compare the total analgesic consumption in first 24 hours among the parturient of four group

  Postoperative total analgesia consumption for first 24 hour

• To compare the frequency of rescue analgesia demanded by parturient in first 24 hours among the groups

  Postoperative period for first 24 hour

• To compare the incidence of side effects like nausea, vomiting, respiratory depression, level of sedation and pruritus in first 24 hours among the groups

  Postoperative period for first 24 hour

Study Arms (4)

Group BF

ACTIVE COMPARATOR

Intrathecal drug used: 0.5% hyperbaric bupivacaine 10mg(2ml) with fentanyl 10mcg(0.2ml), total volume of 2.2ml, single administration, no repetition of intervention In this group, no dose of morphine will be added.

Drug: 0.5% bupivacaine heavy with fentanyl

Group BF-M50

EXPERIMENTAL

Intrathecal drug used : 0.5% hyperbaric bupivacaine 10mg(2ml) with fentanyl 10mcg(0.2ml) plus morphine 50mcg (0.05ml) with total volume of 2.25ml single administration, no repetition of intervention

Drug: 0.5% bupivacaine heavy with fentanyl plus morphine 50 mcg

Group BF-M100

EXPERIMENTAL

Intrathecal drug used : 0.5% hyperbaric bupivacaine 10mg(2ml) with fentanyl 10mcg(0.2ml) plus morphine 100mcg (0.1ml) with total volume of 2.3ml single administration, no repetition of intervention

Drug: 0.5% bupivacaine heavy with fentanyl plus morphine100 mcg

Group BF-M150

EXPERIMENTAL

Intrathecal drug used : 0.5% hyperbaric bupivacaine 10mg(2ml) with fentanyl 10mcg(0.2ml) plus morphine 150mcg (0.15ml) with total volume of 2.35ml single administration, no repetition of intervention

Drug: 0.5% bupivacaine heavy with fentanyl plus morphine 150mcg

Interventions

0.5% bupivacaine heavy with fentanyl DRUG

Spinal anesthesia with 0.5% bupivacaine heavy with fentanyl at L3-L4 intervertebral space using Quincke's spinal needle in sitting position in patients undergoing cesarean section to study the dose with better analgesia profile and lower side effect profile.

Group BF

0.5% bupivacaine heavy with fentanyl plus morphine 50 mcg DRUG

Spinal anesthesia with 0.5% bupivacaine heavy with fentanyl with morphine 50mcg at L3-L4 intervertebral space using Quincke's spinal needle in sitting position in patients undergoing cesarean section to study the dose with better analgesia profile and lower side effect profile.

Group BF-M50

0.5% bupivacaine heavy with fentanyl plus morphine100 mcg DRUG

Spinal anesthesia with 0.5% bupivacaine heavy with fentanyl with morphine 100mcg at L3-L4 intervertebral space using Quincke's spinal needle in sitting position in patients undergoing cesarean section to study the dose with better analgesia profile and lower side effect profile.

Group BF-M100

0.5% bupivacaine heavy with fentanyl plus morphine 150mcg DRUG

Spinal anesthesia with 0.5% bupivacaine heavy with fentanyl with morphine 150mcg at L3-L4 intervertebral space using Quincke's spinal needle in sitting position in patients undergoing cesarean section to study the dose with better analgesia profile and lower side effect profile.

Group BF-M150

Eligibility Criteria

• Age: 18 Years - 45 Years
• Sex: female
• Healthy Volunteers: No
• Age Groups: Adult (18-64)

You may qualify if:

• Pregnant lady \> 36 weeks of gestation presenting for cesarean section under spinal anesthesia
• ASA II/ III
• Maternal Height \> 150 cm
• BMI\< 40 Kg/m2
• Elective Indication

You may not qualify if:

• Patient unwilling to take part in the study
• Patient with known allergy to the study medications
• Contraindication to Spinal Anesthesia

Sponsors & Collaborators

• Tribhuvan University Teaching Hospital, Institute Of Medicine.: lead

Related Publications (2)

• Sultan P, Halpern SH, Pushpanathan E, Patel S, Carvalho B. The Effect of Intrathecal Morphine Dose on Outcomes After Elective Cesarean Delivery: A Meta-Analysis. Anesth Analg. 2016 Jul;123(1):154-64. doi: 10.1213/ANE.0000000000001255.

  PMID: 27089000 BACKGROUND

• Choudhury M. Neuraxial anaesthesia in parturient with cardiac disease. Indian J Anaesth. 2018 Sep;62(9):682-690. doi: 10.4103/ija.IJA_474_18.

  PMID: 30237593 BACKGROUND

MeSH Terms

Conditions

Agnosia; Pain, Postoperative

Interventions

Fentanyl; Morphine

Condition Hierarchy (Ancestors)

Perceptual Disorders; Neurobehavioral Manifestations; Neurologic Manifestations; Nervous System Diseases; Signs and Symptoms; Pathological Conditions, Signs and Symptoms; Postoperative Complications; Pathologic Processes; Pain

Intervention Hierarchy (Ancestors)

Piperidines; Heterocyclic Compounds, 1-Ring; Heterocyclic Compounds; Morphine Derivatives; Morphinans; Opiate Alkaloids; Alkaloids; Heterocyclic Compounds, Bridged-Ring; Heterocyclic Compounds, 4 or More Rings; Heterocyclic Compounds, Fused-Ring; Phenanthrenes; Polycyclic Aromatic Hydrocarbons; Polycyclic Compounds

Central Study Contacts

Bashu Dev Parajuli, MD Anaesthesiology

CONTACT

00977+ 9851179038; bashuparajuli2012@gmail.com

Pooja Poudyal, MD Obstetric and Gynaecology

CONTACT

00977+9841526853; paudyalpooja@yahoo.com

Study Design

• Study Type: interventional
• Phase: phase 4
• Allocation: RANDOMIZED
• Masking: TRIPLE
• Who Masked: PARTICIPANT, INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Dr

Model Details: Prospective double blinded, randomized controlled trial

Study Record Dates

• First Submitted: April 2, 2026
• First Posted: May 1, 2026
• Study Start: April 1, 2026
• Primary Completion (Estimated): December 28, 2026
• Study Completion (Estimated): December 28, 2026
• Last Updated: May 1, 2026

Record last verified: 2026-04

Data Sharing

• IPD Sharing: Will not share