An interventional study of Erector Spinae Plane Block and Intertransverse Process Block in Postoperative Pain Control, Lumbar Spine Surgery and Degenerative Lumbar Spine Diseases, sponsored by Hanoi Medical University. Completed at 1 site in Vietnam. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-10-16.
Sponsored by Hanoi Medical University · Not applicable, Interventional, and Treatment
The goal of this clinical trial is to learn whether two types of ultrasound-guided nerve block, the intertransverse process block and the erector spinae plane block, reduce pain and the need for opioid pain medicines during and after lumbar spine surgery in adults. It also compares the two blocks with each other.
The main questions it aims to answer are:
Do patients who receive either nerve block need less morphine in the first 24 hours after surgery than patients who receive only local anesthetic injected at the skin incision? Is there a difference between the two nerve blocks in pain scores, the amount of opioid medicine needed during and after surgery, the time until patients first ask for pain medicine, and side effects?
Researchers will compare three groups: an erector spinae plane block group, an intertransverse process block group, and a control group that receives local anesthetic infiltration at the incision site.
Participants will:
Be randomly assigned to one of the three groups before surgery Receive the nerve block on both sides of the spine with ropivacaine before general anesthesia (block groups), or local anesthetic infiltration along the planned incision after induction of anesthesia (control group) Undergo general anesthesia and lumbar spine surgery following the same standard protocol Use a patient-controlled analgesia pump that delivers morphine on demand for 24 hours after surgery Rate their pain at rest and during movement at set times over the first 24 hours, and be monitored for side effects such as nausea and vomiting
Background and rationale
Lumbar spine surgery is associated with moderate to severe postoperative pain, and opioid-based analgesia is limited by side effects such as nausea, vomiting, sedation and respiratory depression. The erector spinae plane block (ESPB) is an established component of multimodal analgesia for spine surgery. The intertransverse process block (ITPB) is a more recently described paraspinal technique in which local anesthetic is injected into the tissue between adjacent transverse processes, closer to the paravertebral space. Direct comparisons of the two techniques in lumbar spine surgery are scarce.
Block procedures
Both blocks are performed bilaterally before induction of general anesthesia, with the patient prone, under ultrasound guidance using a low-frequency curvilinear probe and an in-plane approach with a 10-cm block needle.
ESPB: the needle tip is placed between the deep surface of the erector spinae muscle and the posterior surface of the L3 transverse process.
ITPB: the needle tip is placed in the intertransverse space between the L2 and L3 transverse processes, anterior to the erector spinae muscle and posterior to the intertransverse ligament-muscle complex, without advancing further anteriorly.
Needle position is confirmed by hydrodissection with 2 mL of 0.9% saline after negative aspiration. Ropivacaine 0.375% (prepared from ropivacaine 0.5% and 0.9% saline in a 3:1 ratio) is administered at 2.5 mg/kg (maximum 150 mg), divided equally between the two sides. Sensory block is assessed by pinprick 20 minutes after injection using the Hollmén scale, and the cranial and caudal extent of the block is measured in centimetres from the injection level. A block is considered failed if no sensory change is detected 30 minutes after injection.
In the control group, after induction of anesthesia, the surgeon infiltrates 20 mL of 1% lidocaine with epinephrine 1:200,000 into the skin and subcutaneous tissue along both sides of the planned incision before skin incision.
Anesthesia protocol (all groups)
Anesthesia is induced with fentanyl 2 µg/kg, propofol 2-3 mg/kg and rocuronium 0.6 mg/kg, and maintained with sevoflurane at 1-1.5 MAC. Nociceptive response is assessed using the PRST score (blood pressure, heart rate, sweating, tearing). If PRST is ≥ 4, fentanyl 50 µg is given intravenously and may be repeated after 5 minutes. Paracetamol 1 g IV is given approximately 30 minutes before the end of surgery.
Postoperative analgesia
Once patients are awake in the recovery room and able to rate pain and use the device, intravenous morphine patient-controlled analgesia (PCA) is started: morphine 1 mg/mL, bolus 1 mg, lockout interval 8 minutes, no background infusion, maximum 15 mg per 4 hours. Patients are instructed to press the PCA button when pain is VAS ≥ 4. H0 is defined as the time the patient is awake in the recovery room and able to self-report pain and use PCA.
Sample size
Sample size was calculated for comparison of 24-hour morphine consumption between a block group and the control group, assuming a standard deviation of 6.54 mg (from a previous Vietnamese study of ESPB in lumbar spine surgery) and a minimum clinically important difference of 5 mg, with two-sided α = 0.05 and 80% power. This gave 27 patients per group; allowing for about 10% dropout, 30 patients per group (90 in total) were enrolled.
Randomization and statistical analysis
Eligible patients are randomly allocated in a 1:1:1 ratio to the three groups by drawing lots. Continuous variables are compared using one-way ANOVA or the Kruskal-Wallis test, as appropriate, and categorical variables using the chi-square or Fisher's exact test. Pairwise comparisons are adjusted with the Bonferroni method. Two-sided p \< 0.05 is considered statistically significant. Analyses are performed with SPSS version 20.0.
5,640 studies on the registry are indexed under Pain, Postoperative; 1,230 are open to participants now.
This study's enrollment of 90 is above the median of 75 across 4,821 interventional studies indexed under Pain, Postoperative.
Browse Pain, Postoperative studies →Hanoi Medical University is the lead sponsor of 54 studies on the registry; 17 are open to participants now.
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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.
Blood tests of how long blood takes to clot. The INR is the prothrombin time (PT) put on a common scale; about 1 is usual for someone not taking a blood thinner.
Criteria often make an exception for people on a blood thinner such as warfarin, whose INR is raised on purpose.
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
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.
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.
INR, PT and aPTT (clotting tests)
Blood tests of how long blood takes to clot. The INR is the prothrombin time (PT) put on a common scale; about 1 is usual for someone not taking a blood thinner.
Criteria often make an exception for people on a blood thinner such as warfarin, whose INR is raised on purpose.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Platelets
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
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.
Bilateral ultrasound-guided erector spinae plane block at the L3 transverse process before induction of general anesthesia, using ropivacaine 0.375% at 2.5 mg/kg (maximum 150 mg), divided equally between the two sides. Followed by standardized general anesthesia and intravenous morphine patient-controlled analgesia for 24 hours after surgery.
Procedure: Erector Spinae Plane Block · Procedure: Morphine PCA
Bilateral ultrasound-guided intertransverse process block at the L2-L3 level before induction of general anesthesia, using ropivacaine 0.375% at 2.5 mg/kg (maximum 150 mg), divided equally between the two sides. Followed by standardized general anesthesia and intravenous morphine patient-controlled analgesia for 24 hours after surgery.
Procedure: Intertransverse Process Block · Procedure: Morphine PCA
No nerve block. After induction of general anesthesia, the surgeon infiltrates 20 mL of 1% lidocaine with epinephrine 1:200,000 into the skin and subcutaneous tissue along both sides of the planned incision before skin incision. Followed by standardized general anesthesia and intravenous morphine patient-controlled analgesia for 24 hours after surgery.
Procedure: Local anesthetic infiltration · Procedure: Morphine PCA
Bilateral ultrasound-guided injection of local anesthetic between the erector spinae muscle and the L3 transverse process, performed in the prone position before induction of general anesthesia.
Bilateral ultrasound-guided injection of local anesthetic into the intertransverse space between the L2 and L3 transverse processes, anterior to the erector spinae muscle and posterior to the intertransverse ligament complex, performed in the prone position before induction of general anesthesia.
Subcutaneous infiltration along both sides of the planned skin incision by the surgeon after induction of general anesthesia and before skin incision.
Intravenous morphine 1 mg/mL via patient-controlled analgesia: 1 mg bolus, 8-minute lockout interval, no background infusion, maximum 15 mg per 4 hours, for 24 hours after surgery.
Cumulative Morphine Consumption Within 24 Hours After Surgery
Total amount of intravenous morphine (mg) delivered by the patient-controlled analgesia (PCA) pump, including any supplemental morphine, from Hour 0 to Hour 24. Hour 0 is defined as the time the participant is awake in the recovery room and able to self-report pain and use the PCA device.
Time frame: From Hour 0 (awake in the recovery room) to Hour 24 after surgery
Cumulative Morphine Consumption Within 12 Hours After Surgery
Total amount of intravenous morphine (mg) delivered by the PCA pump, including any supplemental morphine, from Hour 0 to Hour 12.
Time frame: From Hour 0 (awake in the recovery room) to Hour 12 after surgery
Pain Score at Rest
Pain intensity at rest measured on a 0-10 Visual Analogue Scale (0 = no pain, 10 = worst imaginable pain). One score is recorded at each time point.
Time frame: Hour 0 (awake in the recovery room), and Hours 1, 2, 4, 8, 12 and 24 after surgery
Pain Score on Movement
Pain intensity on movement measured on a 0-10 Visual Analogue Scale (0 = no pain, 10 = worst imaginable pain). At each time point, the participant is asked to cough and flex the knees, then rates the worst pain experienced during these movements as a single score.
Time frame: Hour 0 (awake in the recovery room), and Hours 1, 2, 4, 8, 12 and 24 after surgery
Total Intraoperative Fentanyl Consumption
Total fentanyl dose (µg) from induction of anesthesia to the end of surgery, including the induction dose and supplemental doses given when the PRST score (blood pressure, heart rate, sweating, tearing) is 4 or higher.
Time frame: From induction of anesthesia to the end of surgery
Intraoperative Heart Rate
Heart rate (beats/min)
Time frame: Before induction, before intubation, after intubation, before skin incision, 5, 15, 30 and 60 minutes after skin incision, before skin closure, and 5 minutes after skin closure.
Intraoperative Mean Arterial Pressure
Mean arterial pressure (mmHg)
Time frame: Before induction, before intubation, after intubation, before skin incision, 5, 15, 30 and 60 minutes after skin incision, before skin closure, and 5 minutes after skin closure
Postoperative Heart Rate
Heart rate (beats/min)
Time frame: Hour 0 (awake in the recovery room), and Hours 1, 2, 4, 8, 12 and 24 after surgery
Postoperative Mean Arterial Pressure
Mean arterial pressure (mmHg)
Time frame: Hour 0 (awake in the recovery room), and Hours 1, 2, 4, 8, 12 and 24 after surgery
Postoperative Respiratory Rate
Respiratory rate (breaths/min)
Time frame: Hour 0 (awake in the recovery room), and Hours 1, 2, 4, 8, 12 and 24 after surgery
Postoperative Peripheral Oxygen Saturation
Peripheral oxygen saturation (%) measured by pulse oximetry
Time frame: Hour 0 (awake in the recovery room), and Hours 1, 2, 4, 8, 12 and 24 after surgery
Time to First Analgesic Request
Time (minutes) from Hour 0 to the participant's first PCA demand. Participants are instructed to press the PCA button when pain is 4 or higher on the Visual Analogue Scale.
Time frame: From Hour 0 (awake in the recovery room) up to Hour 24 after surgery
Plan to share: Yes — De-identified individual participant data underlying the results reported in publications will be shared upon reasonable request to the principal investigator, after approval of a methodologically sound proposal and signing of a data access agreement.
Supporting information: Study protocol, Statistical analysis plan
Time frame: Beginning 3 months and ending 5 years after publication of the main article.
Access criteria: Researchers who provide a methodologically sound proposal for a purpose approved by the principal investigator. Requests should be directed to the corresponding author. Data will be provided without personal identifiers, and sharing will comply with the requirements of the institutional ethics committee.
Ran from Mar 2026 to primary completion in Aug 2026, 5 months.
Of 2,089 non-industry interventional studies with no phase under Pain, Postoperative, half reached primary completion within 11 months of starting (the median), counting those still running; a quarter within 6 and three quarters within 23. This study's 5 months is below that.
Counting every sponsor, half of 2,102 studies reached it within 11 months; a quarter within 6 and three quarters within 23.
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
This study is completed, as verified in Sep 2026. You cannot join it, but the record below documents what was studied.
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Hanoi Medical University