Comparing the Safety and Effectiveness of Different Doses of Morphine Administered in Spinal Anethesia for Pain Relief After Hip Replacement Surgery

Comparison of Safety Profile and Efficacy of Different Doses of Intrathecal Morphine in Total Hip Replacement.

Pain management after total hip replacement is one of the most important aspects of postoperative care for patients and clinicians alike. One of the most common techniques used in anesthesia for this procedure is spinal anesthesia with concurrent administration of opioids into spinal sac. Addition of opioids not only prolongs the anesthesia but also provides pain relief after the procedure for a limited amount of time. Because of its unique chemical properties morphine provides the longest pain relief amongst currently known opioids lasting up to 24 hours. Unfortunately this beneficial effect is associated with both minor and serious adverse effects, most important of which is respiratory depression.

To limit this potenitialy fatal adverse effect dosing of morphine must be very precise in order to balance advantages and risks.

The aim of the study was to assess effectiveness and safety profile of different doses of morphine administered during spinal anesthesia for pain control.

Study Overview

• Status: Recruiting
• Conditions: Total Hip Replacement; Anesthesia, Spinal; Analgesics, Opioid; Adverse Anesthesia Outcome
• Intervention / Treatment: Procedure: Spinal Anesthesia (bupivacaine); Drug: Postoperative pain management with acetaminophen; Device: PCA IV Oxycodone; Drug: Postoperative pain management with dexketoprofen; Drug: Postoperative pain management with metamizole; Drug: Preemptive Analgesics; Device: Patient monitor

• Study Type: Interventional
• Enrollment (Estimated): 120
• Phase: Phase 4

Contacts and Locations

• Study Contact: Name: Szymon Białka, MD PhD; Phone Number: +48323407593; Email: szymon.bialka@gmail.com
• Study Contact Backup: Name: Jakub Żak, MD; Phone Number: +48607936667; Email: jakubzak.sum@gmail.com

Study Locations

• Poland
  • Silesian Voivodeship
    • Sosnowiec, Silesian Voivodeship, Poland, 41-214
      • Recruiting
      • Wojewódzki Szpital Specjalistyczny nr 5 im. św. Barbary
      • Contact: Jakub Żak, MD; Phone Number: +48607936667; Email: jakubzak.sum@gmail.com
      • Sub-Investigator: Jakub Żak, MD
  • West Pomeranian Voivodeship
    • Szczecin, West Pomeranian Voivodeship, Poland, 70-204
      • Not yet recruiting
      • Uniwersytecki Szpital Kliniczny nr 1 im. Prof. Tadeusza Sokołowskiego PUM w Szczecinie
  • Świętokrzyskie Voivodeship
    • Gmina Końskie, Świętokrzyskie Voivodeship, Poland, 26-200
      • Recruiting
      • Zespół Opieki Zdrowotnej w Końskich
      • Principal Investigator: Wojciech Gola, MD PhD
      • Contact: Wojciech Gola, MD PhD; Phone Number: +48504606247; Email: golawojtek@gmail.com

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Informed consent to participate in trial
• Qualification for total hip replacement surgery
• ASA physical status I-III
• BMI 19-30
• Lack of contraindications for drugs and interventions used in trial

Exclusion Criteria:

• Incapability to provide informed consent
• Contraindications for spinal anesthesia
• Preoperative chronic pain
• Chronic use of analgesics
• Obesity (BMI>30)
• Allergies and other contraindications for drugs used in trial
• Mental or physical incapability to operate PCA syringe pump

Study Plan

How is the study designed?

Design Details

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

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: M50; In addition to bupivacaine patients received 50 mcg morphine sulphate intrathecaly.	Procedure: Spinal Anesthesia (bupivacaine); Patients were positioned in sitting position on operating table, interspinous space was identified using anatomical landmarks (intercristal line) and palpation. Entire procedure was conducted with aseptic technique, puncture site was prepared with izopropyl alcohol solution. Skin was anesthetized with subcutaneous injection of 1% lidocaine. Spinal puncture was achieved using median or paramedian technique with 27G pencil-point spinal needle. After confirmation of free flow of cerebrospinal fluid 15 mg of 0,5% bupivacaine was administered intrathecaly. Block level was assessed by lack of sensation to alcohol swab in periumbilical area and complete motor block (Bromage 3).; Drug: Postoperative pain management with acetaminophen; Postoperatively patients received 1,0g of paracetamol every 6 hours,; Device: PCA IV Oxycodone; All patients were equipped with PCA capable syringe pump (Perfusor Space, B. Braun) with 40 milligrams of oxycodone. Care provider explained thoroughly how to operate the device and educated about possible adverse effects.; Drug: Postoperative pain management with dexketoprofen; Postoperatively patients received 50mg of dexketoprofen intravenously every 8 hours.; Drug: Postoperative pain management with metamizole; Postoperatively patients received 1,0g of metamizole intravenously every 6 hours.; Drug: Preemptive Analgesics; After securing intravenous line each patient received preemptive analgesia with 1,0g paracetamol and 1,0g metamizole.; Device: Patient monitor; Postoperatively each patient's vital signs were monitored continuously using patient monitor for 48 hours.
Active Comparator: M100; In addition to bupivacaine patients received 100 mcg morphine sulphate intrathecaly.	Procedure: Spinal Anesthesia (bupivacaine); Patients were positioned in sitting position on operating table, interspinous space was identified using anatomical landmarks (intercristal line) and palpation. Entire procedure was conducted with aseptic technique, puncture site was prepared with izopropyl alcohol solution. Skin was anesthetized with subcutaneous injection of 1% lidocaine. Spinal puncture was achieved using median or paramedian technique with 27G pencil-point spinal needle. After confirmation of free flow of cerebrospinal fluid 15 mg of 0,5% bupivacaine was administered intrathecaly. Block level was assessed by lack of sensation to alcohol swab in periumbilical area and complete motor block (Bromage 3).; Drug: Postoperative pain management with acetaminophen; Postoperatively patients received 1,0g of paracetamol every 6 hours,; Device: PCA IV Oxycodone; All patients were equipped with PCA capable syringe pump (Perfusor Space, B. Braun) with 40 milligrams of oxycodone. Care provider explained thoroughly how to operate the device and educated about possible adverse effects.; Drug: Postoperative pain management with dexketoprofen; Postoperatively patients received 50mg of dexketoprofen intravenously every 8 hours.; Drug: Postoperative pain management with metamizole; Postoperatively patients received 1,0g of metamizole intravenously every 6 hours.; Drug: Preemptive Analgesics; After securing intravenous line each patient received preemptive analgesia with 1,0g paracetamol and 1,0g metamizole.; Device: Patient monitor; Postoperatively each patient's vital signs were monitored continuously using patient monitor for 48 hours.
Active Comparator: M150; In addition to bupivacaine patients received 150 mcg morphine sulphate intrathecaly.	Procedure: Spinal Anesthesia (bupivacaine); Patients were positioned in sitting position on operating table, interspinous space was identified using anatomical landmarks (intercristal line) and palpation. Entire procedure was conducted with aseptic technique, puncture site was prepared with izopropyl alcohol solution. Skin was anesthetized with subcutaneous injection of 1% lidocaine. Spinal puncture was achieved using median or paramedian technique with 27G pencil-point spinal needle. After confirmation of free flow of cerebrospinal fluid 15 mg of 0,5% bupivacaine was administered intrathecaly. Block level was assessed by lack of sensation to alcohol swab in periumbilical area and complete motor block (Bromage 3).; Drug: Postoperative pain management with acetaminophen; Postoperatively patients received 1,0g of paracetamol every 6 hours,; Device: PCA IV Oxycodone; All patients were equipped with PCA capable syringe pump (Perfusor Space, B. Braun) with 40 milligrams of oxycodone. Care provider explained thoroughly how to operate the device and educated about possible adverse effects.; Drug: Postoperative pain management with dexketoprofen; Postoperatively patients received 50mg of dexketoprofen intravenously every 8 hours.; Drug: Postoperative pain management with metamizole; Postoperatively patients received 1,0g of metamizole intravenously every 6 hours.; Drug: Preemptive Analgesics; After securing intravenous line each patient received preemptive analgesia with 1,0g paracetamol and 1,0g metamizole.; Device: Patient monitor; Postoperatively each patient's vital signs were monitored continuously using patient monitor for 48 hours.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Analgesic efficacy	Analgesic efficacy defined as mean value of NRS (Numerical Rating Scale) at 4, 8, 12 ,24 and 48 hours postoperatively at rest and during rehabilitation/movement.	48 hours postoperatively
Safety profile	Frequency of adverse events including excessive sedation (defined as Richmond Agitation Sedation Score RASS≤-1), constipation, postoperative nausea and vomiting, pruritus and respiratory depression defined as sudden drop in respiration rate by ≥90% for ≥10 seconds or cyanosis.	48 hours postoperatively

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Patient satisfaction	Patient satisfaction with pain management measured with Likert scale.; Very satisfied.; Satisfied.; Neither satisfied nor dissatisfied.; Dissatisfied.; Very dissatisfied.	48 hours postoperatively
Length of stay	Length of stay postoperatively.	Up to one week.
Time to rescue analgesia	Amount of time before first bolus of oxycodone delivered by PCA syringe pump.	48 hours postoperatively
Cumulative dose of oxycodone	Cumulative dose of oxycodone over 48 hours postoperatively.	48 hours postoperatively

Collaborators and Investigators

• Sponsor: Medical University of Silesia

Study record dates

Study Major Dates

• Study Start (Actual): March 4, 2025
• Primary Completion (Estimated): June 28, 2026
• Study Completion (Estimated): June 28, 2026

Study Registration Dates

• First Submitted: March 4, 2025
• First Submitted That Met QC Criteria: March 10, 2025
• First Posted (Actual): March 14, 2025

Study Record Updates

• Last Update Posted (Actual): February 12, 2026
• Last Update Submitted That Met QC Criteria: February 11, 2026
• Last Verified: February 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Organic Chemicals; Heterocyclic Compounds, 1-Ring; Heterocyclic Compounds; Diagnostic Techniques and Procedures; Diagnosis; Azoles; Anilides; Amides; Aniline Compounds; Amines; Acetanilides; Anesthesia and Analgesia; Pyrazoles; Anesthesia, Conduction; Anesthesia; Pyrazolones; Aminopyrine; Bupivacaine; Acetaminophen; Dipyrone; Anesthesia, Spinal; dexketoprofen trometamol; Monitoring, Physiologic
• Other Study ID Numbers: SMD-01

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

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