This study aims to compare Laparoscopic assisted LTAP (Transversus Abdominis Plane) to standard port-site infiltration in terms of post-operative visual analogue scores (VAS) for pain at 3, 6, 12 and 24 hours following laparoscopic appendicectomy Tap Block is a standard conventional analgesia protocol for laparoscopic appendicitis used in Beaumont Hospital, and other hospitals throughout Ireland.

The medicinal product for both groups is the same - Bupivacaine. The mode of administration is what this study is reviewing: Control group (Standard port site infiltration) and Study Group - Laparoscopic Transversus Abdominis Plane Block

Title: Randomised Controlled Trial to compare Laparoscopic Transversus Abdominis Plane Block (LTAP) for appendicectomy versus standard treatment Short title: (TAP Block Study) Laparoscopic Transversus Abdominis Plane Block for Appendicectomy - Single-Blinded Randomised controlled study

Objectives: Primary objectives:

To compare LTAP to standard port-site infiltration in terms of post-operative visual analogue scores (VAS) for pain at 3,6, 12 and 24 hours following laparoscopic appendicectomy

Secondary objectives:

Post-operative Opioid requirement Time to first mobilisation post-operatively Length of stay in hospital Quality of Life Questionnaire (at 1 week and 1 month post discharge) (EQ5DL)

Type of trial: Multi centre Single blinded randomised control trial. (Beaumont Hospital and 3 other Dublin Hospitals) Trial design and methods: Study design: randomised controlled Single blind study. Patients will be allocated to one of two parallel groups in a 1:1 fashion. Patients and data analysts will be blinded as to modalities and group allocations. Surgeons and anaesthetists will be made aware of group allocations post randomisation.

Study groups and techniques of anaesthesia:

Control Group: standard port site infiltration using 0.25% plain bupivacaine. The dose is calculated to 2.5mg/kg per body weight. After the appendicectomy is done, after removal of ports and deflating the abdomen, the total calculated dose volume will be infiltrated into the subcutaneous plane at the umbilicus and the other 2 ports sites .

Study group: LTAP block in four points: above and below the umbilicus in both right and left sides; dose calculation 2.5mg per body weight.

After the appendicectomy is done and just before withdrawing port and deflating the abdomen, the operating surgeon will advance a needle into the abdominal wall to the level of the preperitoneal space. Once the needle tip is seen, it is withdrawn slowly and gently about 0.5cm above/superficial to the transversus abdominis (TA) muscle. The surgeon then infiltrates the local anaesthetic into the plane, and the right plane is confirmed by visualising a uniform protrusion downwards of the TA muscle fibres (Doyle's bulge). Seeing a preperitoneal or muscle blister laparoscopically indicates that the infiltration is deeper to this plane, and the needle should be withdrawn more superficially.

Trial duration per participant: 1 month (follow up calls 1 week and 1 month post discharge) Estimated total trial duration: It is estimated that the trial recruitment will take 1 year (based on appendicitis admission rates in both Beaumont Hospital and 3 other Dublin Hospitals). The trial will end once the final patient's follow-up is completed and assessed.

Planned trial sites: Multi-site - sites Beaumont Hospital and 3 other Dublin hospitals Total number of participants planned: 172 86 Control Group 86 Study Group - TAP Block

Inclusion Criteria:

• Provide signed and dated informed consent form
• Willing to comply with all study procedures and be available for follow up telephone follow up
• Male or female, aged over 18
• Diagnosed either clinically or radiologically (CT/US/MRI) with appendicitis
• Uncomplicated or complicated appendicitis
• Undergoing laparoscopic appendicitis surgery only
• Must be fluent in English in order to complete telephone follow up questionnaire
• Fulfillment of each criteria must be clearly evidenced (in lab reports or correspondence) and/or documented in the medical records.

Exclusion Criteria:

• Male or female under the age or 18
• Laparoscopic converted to open appendicectomy (during surgical procedure)
• Open appendicectomy (planned)
• Pregnancy.
• Females must not be breastfeeding
• Known allergic reactions to components of the study product(s) )
• Not fluent in English - which would prevent participants to complete follow up telephone questionnaire
• Malignant appendicitis
• Spinal Anaesthesia, Epidural analgesia catheter or injections, Post-operative requirements for patient controlled analgesia (PCA)
• Right hemicolectomy or any concomitant or simultaneous intervention
• Allergy or hypersensitivity to any of the components of Bupivacaine
• Presence of any other illness or condition that renders the patient unsuitable for trial participation in the opinion of the investigator

Paper will be published in surgical journals

6 months after close of study when analyses is completed

All findings will be published in surgical journals

Single blinded randomised control trial