An interventional study of Pericapsular nerve group (PENG) block and Intrathecal Morphine in Postoperative Pain, sponsored by Erzincan Binali Yildirim Universitesi. Not yet recruiting at 1 site in Turkey (Türkiye). Open to participants aged 18 Years to 85 Years. Per ClinicalTrials.gov, last updated 2026-09-09.
Sponsored by Erzincan Binali Yildirim Universitesi · Not applicable, Interventional, and Treatment
The goal of this clinical trial is to compare the PENG block with intrathecal morphine for early postoperative recovery and pain control in adults undergoing elective total hip arthroplasty. The main question it aims to answer is:
Is there a difference between PENG block and intrathecal morphine in quality of recovery 24 hours after surgery, as measured by the Quality of Recovery-15 (QoR-15) questionnaire?
Researchers will also compare postoperative pain, opioid use, mobilization, motor function, and treatment-related side effects between the two groups.
Participants will be randomly assigned to receive either a PENG block or intrathecal morphine in addition to spinal anesthesia and standard multimodal pain treatment. Participants will complete the QoR-15 questionnaire before surgery and 24 hours after surgery. Pain scores, opioid use, mobilization, motor function, and side effects will be assessed during the first 24 hours after surgery.
Total hip arthroplasty is a major orthopedic procedure associated with substantial postoperative pain, which may interfere with early mobilization, functional recovery, and overall quality of recovery. Effective multimodal analgesia is therefore an important component of perioperative care. Intrathecal morphine provides prolonged postoperative analgesia but may be associated with opioid-related adverse effects, including nausea and vomiting, pruritus, urinary retention, and respiratory depression. The pericapsular nerve group (PENG) block is a regional analgesic technique targeting the sensory innervation of the anterior hip capsule and has been proposed as a potentially motor-sparing approach to analgesia after hip surgery.
This is a prospective, randomized, controlled, assessor-blinded, single-center clinical trial comparing PENG block with intrathecal morphine in patients undergoing elective primary unilateral total hip arthroplasty under spinal anesthesia. A total of 90 participants will be enrolled and randomly assigned in a 1:1 ratio using computer-generated randomization. Allocation will be concealed using sealed opaque envelopes. Because of the nature of the interventions, the anesthesiologist performing the procedures cannot be blinded. Investigators performing postoperative assessments and the investigator performing the statistical analysis will be blinded to group allocation.
Perioperative anesthesia and analgesia will be standardized for both groups. All participants will undergo routine standard monitoring and receive spinal anesthesia with 10-15 mg of 0.5% hyperbaric bupivacaine. All participants will also receive 8 mg of intravenous dexamethasone intraoperatively.
Participants assigned to the PENG group will receive an ultrasound-guided PENG block with a total injectate volume of 20 mL. The intended PENG block dose will be 100 mg of bupivacaine (20 mL of 0.5% bupivacaine). For safety, the bupivacaine dose will be reduced when necessary to ensure that the total bupivacaine dose, including the dose administered for spinal anesthesia, does not exceed 2 mg/kg. When dose reduction is required, an appropriate volume of 0.5% bupivacaine will be combined with 0.9% saline to maintain a total PENG block injectate volume of 20 mL.
Participants assigned to the intrathecal morphine group will receive 100 micrograms of preservative-free intrathecal morphine during spinal anesthesia. Apart from the randomized analgesic intervention, perioperative management will be standardized between the two groups.
Postoperative multimodal analgesia will be standardized for all participants. Paracetamol 1 g will be administered intravenously or orally every 8 hours, and dexketoprofen trometamol 50 mg will be administered intravenously every 12 hours. Rescue analgesia will consist of intravenous tramadol 1 mg/kg when the Numeric Rating Scale (NRS) pain score is 4 or higher. Postoperative opioid consumption will be recorded and converted to morphine-equivalent doses.
The study is designed to compare the effects of these two analgesic strategies on early patient-centered recovery after total hip arthroplasty while also evaluating their analgesic, functional, and adverse-effect profiles. Recovery status will be assessed before surgery to account for individual differences in baseline recovery-related health status, and postoperative assessments will be performed by investigators blinded to treatment allocation.
Exclusion Criteria:
Participants assigned to this group will receive an ultrasound-guided PENG block after spinal anesthesia. The PENG block will have a total injectate volume of 20 mL, with an intended dose of 100 mg bupivacaine (20 mL of 0.5% bupivacaine). The bupivacaine dose will be reduced when necessary to ensure that the total bupivacaine dose, including the dose administered for spinal anesthesia, does not exceed 2 mg/kg. When dose reduction is required, 0.9% saline will be added to maintain a total injectate volume of 20 mL. All other perioperative anesthesia and multimodal analgesia will be standardized.
Procedure: Pericapsular nerve group (PENG) block
Participants assigned to this group will receive 100 micrograms of preservative-free intrathecal morphine during spinal anesthesia. All other perioperative anesthesia and multimodal analgesia will be standardized.
Drug: Intrathecal Morphine
Participants will receive an ultrasound-guided pericapsular nerve group (PENG) block after spinal anesthesia. The total injectate volume will be 20 mL, with an intended dose of 100 mg bupivacaine (20 mL of 0.5% bupivacaine). The bupivacaine dose will be reduced when necessary to ensure that the total bupivacaine dose, including the dose administered for spinal anesthesia, does not exceed 2 mg/kg. When dose reduction is required, 0.9% saline will be added to maintain a total injectate volume of 20 mL.
100 micrograms of preservative-free morphine administered intrathecally during spinal anesthesia
Quality of Recovery-15 (QoR-15) Score at 24 Hours After Surgery
Quality of recovery will be assessed using the 15-item Quality of Recovery (QoR-15) questionnaire. The total score ranges from 0 to 150, with higher scores indicating better quality of recovery. The questionnaire will be administered preoperatively to assess baseline recovery status and repeated 24 hours after surgery. The primary outcome will be the QoR-15 score at 24 hours after surgery.
Time frame: 24 hours after surgery
Pain at Rest Assessed by the Numeric Rating Scale (NRS)
Pain at rest will be assessed using an 11-point Numeric Rating Scale (NRS), ranging from 0 (no pain) to 10 (worst imaginable pain). A preoperative measurement will be obtained as the baseline value, and postoperative measurements will be compared with baseline and between the study groups.
Time frame: Preoperatively and at 3, 6, 12, and 24 hours after surgery
Pain During Straight Leg Raise Assessed by the Numeric Rating Scale (NRS)
Pain during active straight leg raise will be assessed using an 11-point Numeric Rating Scale (NRS), ranging from 0 (no pain) to 10 (worst imaginable pain). A preoperative measurement will be obtained as the baseline value, and postoperative measurements will be compared with baseline and between the study groups.
Time frame: Preoperatively and at 3, 6, 12, and 24 hours after surgery
Cumulative Postoperative Opioid Consumption
Total opioid consumption during the first 24 hours after surgery will be recorded. Administered opioids will be converted to intravenous morphine-equivalent doses for comparison between groups.
Time frame: From the end of surgery to 24 hours after surgery
Time to First Postoperative Mobilization
Time from the end of surgery to the participant's first postoperative mobilization will be recorded.
Time frame: From the end of surgery to first mobilization, assessed up to 24 hours after surgery
Overall Benefit of Analgesia Score (OBAS)
Overall postoperative analgesic benefit will be assessed using the Overall Benefit of Analgesia Score (OBAS), a 7-item multidimensional instrument that incorporates pain intensity, opioid-related adverse effects, and patient satisfaction with pain treatment. The total OBAS ranges from 0 to 28, with lower scores indicating a greater overall benefit of analgesia and higher scores indicating a worse outcome.
Time frame: 24 hours after surgery
Incidence of Postoperative Nausea and Vomiting
The number of participants experiencing postoperative nausea and/or vomiting will be recorded.
Time frame: Within the first 24 hours after surgery
Incidence of Pruritus
The number of participants experiencing pruritus during the postoperative period will be recorded.
Time frame: Within the first 24 hours after surgery
Incidence of Urinary Retention
The number of participants experiencing postoperative urinary retention will be recorded.
Time frame: Within the first 24 hours after surgery
Incidence of Respiratory Depression
The number of participants experiencing postoperative respiratory depression will be recorded.
Time frame: Within the first 24 hours after surgery
Ability to Perform Active Straight Leg Raise
Motor function will be assessed by the participant's ability to actively raise the operated leg from the bed with the knee extended. The assessment will be recorded as successful or unsuccessful.
Time frame: Preoperatively and at 3, 6, 12, and 24 hours after surgery
Plan to share: No
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Erzincan Binali Yildirim Universitesi