An interventional study of Ultrasound-Guided Transversus Abdominis Plane Block and Ultrasound-Guided Linea Semilunaris Block in Postoperative Pain and Opioid Consumption, sponsored by Saglik Bilimleri Universitesi Gazi Yasargil Training and Research Hospital. Not yet recruiting at 1 site in Turkey (Türkiye). Open to participants aged 1 Year to 18 Years. Per ClinicalTrials.gov, last updated 2026-09-03.
Sponsored by Saglik Bilimleri Universitesi Gazi Yasargil Training and Research Hospital · Not applicable, Interventional, and Treatment
The aim of this prospective randomized controlled trial is to compare the postoperative analgesic efficacy of ultrasound-guided transversus abdominis plane (TAP) block and umbilical paramedian linea semilunaris block in pediatric patients undergoing elective laparoscopic abdominal surgery.
A total of 56 pediatric patients will be randomly assigned in a 1:1 ratio to receive either a TAP block or a linea semilunaris block after induction of general anesthesia and before the start of surgery. Both blocks will be performed under ultrasound guidance using 0.2% bupivacaine at a volume of 0.5 mL/kg, with the total dose limited to 2 mg/kg.
The primary outcome will be total opioid consumption during the first 24 hours after surgery. Secondary outcomes will include postoperative pain scores, time to first analgesic requirement, additional analgesic requirements, postoperative nausea and vomiting, and block-related complications.
Effective postoperative pain management is an important component of perioperative care in pediatric patients. Inadequately controlled postoperative pain may result in agitation, delayed mobilization, delayed oral intake, prolonged hospitalization, and increased analgesic requirements. Although opioids are commonly used for postoperative analgesia, their use in pediatric patients may be associated with adverse effects such as nausea, vomiting, sedation, respiratory depression, and delayed recovery. Therefore, opioid-sparing multimodal analgesic strategies, including ultrasound-guided regional anesthesia techniques, have become increasingly important in pediatric perioperative care.
The transversus abdominis plane (TAP) block is one of the commonly used abdominal wall blocks in pediatric abdominal surgery. However, its dermatomal distribution may be variable, and adequate analgesia may require bilateral or multiple injections. The linea semilunaris block is a more recently described fascial plane block targeting the anatomical region where the internal oblique and transversus abdominis muscles converge. This approach may allow wider local anesthetic spread and potentially provide effective analgesia for both the lateral abdominal wall and regions closer to the midline. However, clinical evidence regarding the linea semilunaris block remains limited, particularly in pediatric patients.
This prospective, randomized controlled trial will include 56 pediatric patients undergoing elective laparoscopic abdominal surgery. After written informed consent is obtained from a parent or legal guardian, participants will be randomly assigned in a 1:1 ratio using a computer-generated randomization sequence and sequentially numbered, sealed, opaque envelopes.
Following induction of general anesthesia and before the start of surgery, participants will receive one of two ultrasound-guided regional anesthesia techniques. Participants assigned to the linea semilunaris block group will receive an ultrasound-guided linea semilunaris block, whereas participants assigned to the TAP block group will receive an ultrasound-guided transversus abdominis plane block. In both groups, 0.2% bupivacaine will be administered at a volume of 0.5 mL/kg, with the total bupivacaine dose limited to 2 mg/kg. All block procedures will be performed by anesthesiologists experienced in pediatric ultrasound-guided regional anesthesia.
All participants will receive standard general anesthesia and perioperative monitoring. Postoperative pain will be assessed using age-appropriate FLACC or Wong-Baker Faces pain scales at predefined postoperative time points.
The primary outcome of the study will be total opioid consumption during the first 24 hours after surgery. Secondary outcomes will include postoperative pain scores, time to first analgesic requirement, additional analgesic requirements, postoperative nausea and vomiting, and block-related complications. The study aims to determine whether the linea semilunaris block provides effective postoperative analgesia and reduces opioid requirements compared with the TAP block in pediatric laparoscopic abdominal surgery.
5,640 studies on the registry are indexed under Pain, Postoperative; 1,230 are open to participants now.
This study's planned enrollment of 56 is below the median of 75 across 4,821 interventional studies indexed under Pain, Postoperative.
Browse Pain, Postoperative studies →Saglik Bilimleri Universitesi Gazi Yasargil Training and Research Hospital is the lead sponsor of 59 studies on the registry; 25 are open to participants now.
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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.
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.
Participants randomized to this group will receive an ultrasound-guided transversus abdominis plane (TAP) block after induction of general anesthesia and before the start of surgery. The block will be performed using 0.2% bupivacaine at a volume of 0.5 mL/kg, with the total bupivacaine dose limited to 2 mg/kg.
Procedure: Ultrasound-Guided Transversus Abdominis Plane Block
Participants randomized to this group will receive an ultrasound-guided umbilical paramedian linea semilunaris block after induction of general anesthesia and before the start of surgery. After identification of the linea semilunaris and confirmation of the target plane by hydrodissection, 0.2% bupivacaine will be administered at a volume of 0.5 mL/kg, with the total bupivacaine dose limited to 2 mg/kg.
Procedure: Ultrasound-Guided Linea Semilunaris Block
Following induction of general anesthesia and before the start of surgery, an ultrasound-guided transversus abdominis plane (TAP) block will be performed. After identification of the target fascial plane and confirmation by hydrodissection, 0.2% bupivacaine will be administered at a volume of 0.5 mL/kg. The total bupivacaine dose will be limited to 2 mg/kg.
Following induction of general anesthesia and before the start of surgery, an ultrasound-guided umbilical paramedian linea semilunaris block will be performed. The linea semilunaris will be identified under ultrasound guidance, and the appropriate fascial plane will be confirmed by hydrodissection. Subsequently, 0.2% bupivacaine will be administered at a volume of 0.5 mL/kg. The total bupivacaine dose will be limited to 2 mg/kg.
Total Postoperative Opioid Consumption During the First 24 Hours
Total opioid consumption administered for postoperative analgesia will be recorded during the first 24 hours after surgery.
Time frame: First 24 hours after surgery
Postoperative Pain Scores
Postoperative pain intensity will be assessed using age-appropriate pain assessment scales (FLACC or Wong-Baker Faces Pain Rating Scale).
Time frame: At 0 and 30 minutes, and 4, 8, 12, and 24 hours postoperatively
Plan to share: No — Individual participant data (IPD) will not be shared.
No publications or documents are linked to this record.
Start is estimated for Aug 2026; primary completion for Dec 2026, 3 months later.
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 planned 3 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.
This study is not yet recruiting, as verified in Aug 2026. You cannot join it, but the record below documents what was studied.
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Saglik Bilimleri Universitesi Gazi Yasargil Training and Research Hospital