Prospective, Randomized Comparative Study Between an Anesthesiological, Ultrasound-guided, and a Laparoscopic, Landmark-based Application of a "Transversus Abdominis Plane (TAP) Block" Based on Postoperative Pain Perception, Postoperative Analgesic Requirement, and Procedure Duration

The Transversus Abdominis Plane Block (TAP) has become one of the most established and frequently performed trunk wall blocks for perioperative analgesia in abdominal surgical procedures. The TAP-Block can be performed by both surgeons and anaesthetists.

The goal of this prospective, randomized study is to compare an anesthesiological, ultrasound-guided "Transversus Abdominis Plane (TAP) Block" with a laparoscopic, landmark-based "Transversus Abdominis Plane (TAP) Block"

The main questions it aims to answer are:

Primary Hypothesis: There are no differences in postoperative pain perception and analgesic requirements between the anaesthesiological ultrasound-guided and the surgical laparoscopic landmark-based TAP block

Secondary Hypothesis: There are no significant differences in the duration of the procedure between the anaesthesiological, ultrasound-guided and the surgical laparoscopic landmark-based TAP block.

Study Overview

• Status: Completed
• Conditions: Regional Anaesthesia; Transversus Abdominis Plane Block
• Intervention / Treatment: Procedure: Arm 1: The anaesthesiologically performed, ultrasound-guided, 4 quadrant-TAP block ( a combination of a lateral with a subcostal TAP block bilaterally); Procedure: Arm2: The surgically performed, laparoscopic landmark-based assisted TAP block

Detailed Description

The Transversus Abdominis Plane Block (TAP) has become one of the most established and frequently performed trunk wall blocks for perioperative analgesia in abdominal surgical procedures. A TAP block is a so-called trunk wall block where a targeted injection of high volumes of local anesthetics is made into a space between two muscle fascias, the so-called inter-fascial space. In this inter-fascial space, the cutaneous nerve branches of various anterior rami of the spinal nerves run and innervate somatosensory in the respective dermatome, skin, soft tissues, and bones, as well as the outer layers of the pleura and peritoneum. Specifically, in a TAP block, the nerve fibers of the spinal nerves from the spinal segments Th6 to L1 can be anaesthetized by applying local anaesthetics between the Musculus obliquus internus abdominis and the Musculus transversus abdominis. The block produces somatic analgesia of the skin, muscles, and bony structures. Visceral analgesia of the internal organs is not achieved. Therefore, the TAP block mainly has an indication within the framework of a multimodal pain concept to save central and peripheral analgesics.

In the literature, it is shown that especially laparoscopic procedures benefit from a TAP block in terms of reducing postoperative reported pain intensity and reducing postoperative opioid requirements. Compared to simple wound infiltration with a local anaesthetic or simple local anaesthesia of the trocar insertion sites in a laparoscopy, the TAP block has been shown to be a more effective method in multiple studies.

The so-called Transversus Abdominis Plane compartment can be reached using various approaches (posterior, lateral, subcostal) and puncture techniques (landmark-based, ultrasound-guided, and surgical). A lateral approach is used primarily for analgesia in lower abdominal surgery (e.g., inguinal hernia repair). A subcostal approach is used primarily for analgesia in upper abdominal/supraumbilical surgery (e.g., cholecystectomy). A dual TAP block or '4 quadrant block,' the combination of a lateral with subcostal TAP block, could achieve better abdominal distribution of the local anaesthetic and more complete analgesia for the lower (T10-T12) and upper (T6-T9) abdomen.

The goal of this monocentric, prospective, randomised study is to compare an anesthesiological, ultrasound-guided "Transversus Abdominis Plane (TAP) Block" with a laparoscopic, landmark-based "Transversus Abdominis Plane (TAP) Block" in two parallel study arms.

Anaesthesia Induction and maintenance in both groups are standardised and similar.

The main questions to answer are:

Primary Hypothesis: There are no differences in postoperative pain perception and analgesic requirements between the anaesthesiological ultrasound-guided and the surgical laparoscopic landmark-based TAP block

Secondary Hypothesis: There are no significant differences in the duration of the procedure between the anaesthesiological, ultrasound-guided and the surgical laparoscopic landmark-based TAP block.

A sample size calculation was performed before study start. The hypotheses will be verified by suitable statistical analysis. The randomization process is performed preoperatively using a closed envelope ('Sealed Envelope') that assigns a patient to one of the two intervention groups.

• Study Type: Interventional
• Enrollment (Actual): 64
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Germany
  • Hesse
    • Offenbach, Hesse, Germany, 63069
      • Director of the Department of Anaesthesiology, Intensive Care Medicine, and Pain Therapy at the Sana Klinikum Offenbach

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Consent of the adult patient
• Elective laparoscopic-assisted colorectal surgery, elective laparoscopic cholecystectomy, or elective laparoscopic fundoplication

Exclusion Criteria:

• Lack of patient consent
• Pregnancy and breastfeeding
• Allergies to local anaesthetics used
• Infections at the puncture sites
• History of complex abdominal wall reconstruction
• Chronic pain syndrome
• Fibromyalgia
• Chronic opioid use
• Chronic alcohol abuse
• Chronic drug abuse (THC, amphetamines, cocaine, etc.)
• Psychiatric preconditions (depression, schizophrenia, etc.)
• Patients with impaired consciousness, communication, or cognitive function
• Diagnosed coagulopathies (e.g., platelet count <80,000/µL, PTT/aPTT- prolongation >1.5 upper normal value)
• Therapeutic anticoagulation

Study Plan

How is the study designed?

Design Details

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

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Arm 1: anaesthesiologically performed, ultrasound-guided, dual (lateral & subcostal) TAP block; The anaesthesiologically performed, ultrasound-guided, 4 quadrant-TAP block ( a combination of a lateral with a subcostal TAP block bilaterally) is performed by an experienced anaesthetist after induction of anaesthesia and before the start of the surgery. A total of 4 punctures are performed. Injection of a total of 60 ml ropivacaine 0.2% into the target compartment (2x 20 ml laterally, 2x 10 ml subcostally)	Procedure: Arm 1: The anaesthesiologically performed, ultrasound-guided, 4 quadrant-TAP block ( a combination of a lateral with a subcostal TAP block bilaterally); Injection of a total of 60 ml ropivacaine 0.2% into the target compartment (2x 20 ml laterally, 2x 10 ml subcostally)
Active Comparator: Arm 2: surgically performed, laparoscopic landmark-based TAP block; The surgically performed, laparoscopic landmark-based assisted TAP block is performed intraoperatively by the surgeon after the establishment of the pneumoperitoneum and the insertion of the camera. The puncture needle is inserted from the outside under continuous laparoscopic visualization. The spread of the local anaesthetic is continuously visually monitored and should cause a bulging of M. transversus abdominis inward, away from M. obliquus internus ('Doyle's Bulge'). Injection of a total of 6 x 10 ml = 60 ml ropivacaine 0.2% into the target compartment (at 3 defined puncture sides bilaterally: at the anterior axillary line at 2 different, fixed heights and at the midclavicular line subcostally)	Procedure: Arm2: The surgically performed, laparoscopic landmark-based assisted TAP block; Injection of a total of 6 x 10 ml = 60 ml ropivacaine 0.2% into the target compartment (at 3 defined puncture sides bilaterally: at the anterior axillary line at 2 different, fixed heights and at the midclavicular line subcostally)

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Assessment of the postoperative pain perception using the NRS pain scale	Standardized pain assessments postoperatively are conducted by the in-house anaesthesiological pain service using a standardized pain form (which consists of a NRS Scoring in rest and at motion at fixed times [1 hour, 2 hours, 6 hours, 12 hours, 24 hours]). The anaesthesiological pain service is blinded to the procedure performed.	First 24 hours postoperatively
Assessment of the postoperative analgesic requirements/consumption within the first 24 hours after surgery	An assessment of the cumulative analgesic consumption in the first 24 hrs. postoperatively is conducted by the in-house anaesthesiological pain service. Both total opioid consumption (in mg) and consumption of basic analgetics (e.g. paracetamol, metamizole, etc.)(in mg) are measured. The anaesthesiological pain service is blinded to the procedure performed.	First 24 hours postoperatively

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Duration of the TAP block procedure	Duration of the TAP block procedure, defined as the time from the first needle introduction to the completed application of the total amount of the local anaesthetic (in minutes).	perioperatively

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
PONV-Incidence	The incidence of PONV	First 24 hours postoperatively
Duration of the patient stay in the recovery room	Total amounts of minutes that the patient was monitored in the recovery room before dismissal to normal ward	First 24 hours postoperatively
Complications	Incidence of complications	First 24 hours postoperatively

Collaborators and Investigators

• Sponsor: Sana Klinikum Offenbach
• Investigators: Principal Investigator: Prof.Dr. H. Mutlak, Department of Anaesthesiology, Intensive Care Medicine, and Pain Therapy at the Sana Klinikum Offenbach

Study record dates

Study Major Dates

• Study Start (Actual): March 25, 2025
• Primary Completion (Actual): June 6, 2025
• Study Completion (Actual): June 6, 2025

Study Registration Dates

• First Submitted: March 4, 2025
• First Submitted That Met QC Criteria: March 13, 2025
• First Posted (Actual): March 14, 2025

Study Record Updates

• Last Update Posted (Actual): April 22, 2026
• Last Update Submitted That Met QC Criteria: April 18, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Keywords: Transversus Abdominis Plane Block; prospective randomised trial; 4 quadrant TAP-Block; ultrasound-guided Transversus Abdominis Plane Block; laparoscopic, landmark-based Transversus Abdominis Plane Block
• Additional Relevant MeSH Terms: Pain; Neurologic Manifestations; Postoperative Complications; Pathologic Processes; Pain, Postoperative
• Other Study ID Numbers: 2023-3472-evBO

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No