A Phase 4 interventional study of Intrathecal Morphine in Postoperative Pain, Cesarean Section and Obstetric Anesthesia, sponsored by Hospital Universitario de Caracas. Completed at 1 site in Venezuela. Open to female participants aged 18 Years to 45 Years. Per ClinicalTrials.gov, last updated 2026-04-08.
Sponsored by Hospital Universitario de Caracas · Phase 4, Interventional, and Treatment
This study evaluates the efficacy and safety of two different doses of intrathecal morphine (75 mcg versus 100 mcg) for postoperative analgesia in patients undergoing elective cesarean delivery under spinal anesthesia. Effective postoperative pain control is essential to improve maternal recovery, facilitate early mobilization, and enhance neonatal care. Participants were randomly of assigned to receive either 75 mcg or 100 mcg of intrathecal morphine dose that provides effective analgesia while minimizing adverse effects in the obstetric population.
This prospective, randomized, double-blind controlled trial was designed to compare the analgesic efficacy and safety of two doses of intrathecal morphine (75 mcg versus 100 mcg) in patients undergoing elective cesarean delivery under spinal anesthesia. A total of 240 ASA physical status II patients schedule for elective cesarean delivery were enrolled and randomly assigned into two parallel groups. Patients received either 75 mcg or 100 mcg of intrathecal morphine as part of a standardized spinal anesthesia technique using local anesthetic. Randomization was performed using a predefined allocation method, and both patients and outcome assessors were blinded to group assignment. Perioperative management was standardized across both groups to minimize confounding variables. Postoperative pain intensity was assessed using the Visual Analog Scale (VAS) at 2, 4, 8, 12 and 24 hours following surgery. The primary outcome was VAS pain score at 24 hours. Secondary outcomes included pain scores at earlier time points, requirement for rescue analgesia, incidence of opioid-related adverse effects (nausea, vomiting, pruritus), and neonatal outcomes assessed by Apgar scores. The objetive of this study was to determinethe optimal intrathecal morphine dose that provides effective postoperative analgesia while minimizing adverse effects in the obstetric population. The study was conducted in accordance with institutional ethical standards and approved by the corresponding ethics committee.
5,640 studies on the registry are indexed under Pain, Postoperative; 1,230 are open to participants now.
This study's enrollment of 240 is above the median of 75 across 4,821 interventional studies indexed under Pain, Postoperative.
Browse Pain, Postoperative studies →Hospital Universitario de Caracas is the lead sponsor of 4 studies on the registry; none are open to participants now.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
The anaesthetists’ scale of health before surgery: I is healthy, II has a mild illness that is under control, III a severe one, IV a severe illness that is a constant threat to life. V and VI are used for the critically ill and for organ donors.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
ASA physical status
The anaesthetists’ scale of health before surgery: I is healthy, II has a mild illness that is under control, III a severe one, IV a severe illness that is a constant threat to life. V and VI are used for the critically ill and for organ donors.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
BMI (body mass index)
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants receive a single intrathecal dose of 75 mcg morphine during spinal anesthesia for elective cesarean delivery.
Drug: Intrathecal Morphine
Participants receive a single intrathecal dose of 100 mcg morphine during spinal anesthesia for elective cesarean delivery.
Drug: Intrathecal Morphine
Intrathecal administration of preservative-free morphine sulfate at doses of 75 mcg or 100 mcg as part of spinal anesthesia for elective cesarean delivery. The drug is administered once at the time the spinal anesthesia to provide postoperative analgesia.
Also known as: Morphine sulfate
Postoperative pain intensity at 24 hours
Pain intensity will be assessed using the Visual Analog Scale (VAS, 0-10), where 0 indicates no pain and 10 indicates worst imaginable pain. Measurements will be recorded at 2, 4, 8, 12 and 24 hours after surgery. The primary endpoint is the VAS score at 24 hours.
Time frame: 24 hours after cesarean delivery
Total opioid consumption within 24 horas
Total supplemental opioid requirement (e.g., tramadol or morphine equivalents) during the first 24 hours postoperatively.
Time frame: 0 - 24 hours after surgery
Incidence of postoperative nausea and vomiting (PONV)
Number of patients experiencing nausea and/or vomiting requiring treatment.
Time frame: 0 - 24 hours after surgery.
Incidence of pruritus
Number of patients reporting clinically significant itching requiring treatment.
Time frame: 0 - 24 hours after surgery.
Time to first rescue analgesia
Time elapsed from spinal anesthesia to first request for additional analgesia.
Time frame: 0 - 24 hours after surgery.
Neonatal outcome
Apgar scores assessed at 1 and 5 minutes after birth
Time frame: at birth (1 and 5 minutes)
Plan to share: Undecided — Individual participant data (IPD) sharing has not yet been determined. Data may be shared upon reasonable request after study completion, subject to institutional approval, ethical considerations, and data protection regulations.
Ran from Jan 2023 to primary completion in Jun 2024, 17 months.
Of 531 non-industry phase 4 interventional studies under Pain, Postoperative, half reached primary completion within 16 months of starting (the median), counting those still running; a quarter within 8 and three quarters within 32. This study's 17 months is close to that.
Counting every sponsor, half of 541 studies reached it within 16 months; a quarter within 8 and three quarters within 32.
How these figures are worked out, and which studies are left out of them.
This study is completed, as verified in Apr 2026. You cannot join it, but the record below documents what was studied.
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Studies of the drug tested here: Morphine
Hospital Universitario de Caracas