Comparison of the Analgesic Effects of Surgical Site Bupivacaine and Tramadol Infiltration After Appendectomy

Comparison of the analgesic effects of surgical site infiltration of bupivacaine versus tramadol in patients undergoing appendectomy under general anesthesia.

Randomized, double‑blind, parallel‑group, active‑controlled, phase 3 clinical trial on 80 patients (40 patients per group). Randomization will be performed using the random number generation function of SPSS software.

The study will be conducted at AL-Jumhouri Hospital هin Neynava , Iraq. Appendectomy candidates, after confirming eligibility, will be randomly allocated to two groups. The surgeon will infiltrate the drug at the surgical site. The patient, pain assessor, and statistical analyst will be blinded

Inclusion Criteria : Age between 18 and 65 years. Candidate for appendectomy under general anesthesia. ASA physical status class I or II Ability to provide written informed consent. Exclusion Criteria : Known allergy to any of the study medications. History of chronic opioid use Severe cardiac, hepatic, renal, or advanced neurological disorders. Pregnancy or breastfeeding. Body Mass Index greater than 35 kg/m². Diagnosis of perforated appendicitis or generalized peritonitis requiring extensive surgery. Inability to communicate effectively for reliable pain score assessment.

Group Bupivacaine: Receives 20 mL of bupivacaine 0.25% (50 mg) as layer‑by‑layer infiltration at the surgical site. Group Tramado: Receives 100 mg of tramadol dissolved in 20 mL of normal saline as layer‑by‑layer infiltration at the surgical site.

Postoperative pain intensity measured by VAS, at PACU arrival and at 1, 2, 4, 6, 12, and 24 hours after surgery.

n this randomized controlled clinical trial, the Simple Randomization method using computer-generated random numbers will be employed(Uniform Random Number Generator). This method is a fully probabilistic (random) approach in which each participant has an entirely equal and independent chance of being allocated to either of the two intervention groups. In this method, the randomization sequence is designed in such a way that allocation of each patient to groups is not predictable in any way and is based solely on chance and probability. The probability of allocation to each group is 50% (1:1 ratio)

In this study, blinding is designed as a double‑blind trial with the exception that the injecting physician is not blind, while the patient, data collector , and statistical analyst will all remain blind to the patient's group allocation. The study drugs (bupivacaine 0.25% and tramadol 100 mg dissolved in normal saline) will be prepared by an independent pharmacist in identical 20 mL syringes with clear and colorless appearance, and will be labeled only with group codes (A or B). After opening the randomization envelope, only the surgeon will be informed of the group code and will inject the corresponding drug at the surgical site. The patient, anesthesia team, nurses, and pain assessor will remain unaware of the injected drug type. The statistical analyst will receive data coded as A and B, and unblinding will be performed after analysis completion. To maintain blinding throughout the study, all team members are obligated to preserve blinding, and no information about the patient's group will be disclosed to the pain assessor or patient. In case of any accidental disclosure of the patient's group, this will be recorded as a "Breach of Blinding" in the data collection form and will be considered in the final analysis

All data will remain confidential in accordance with the ethical commitment, and only aggregated group-level results will be published in the form of a final article or report

Individual participant data will not be shared. The only publishable documents include the aggregated study results in the form of the final manuscript and the Statistical Analysis Plan (SAP). Study results will be disseminated through publication in a reputable national or international peer-reviewed journal in the field of anesthesiology, as well as presentation at relevant scientific conferences

Access to SAP: immediately after IRCT registration. Access to aggregated results (manuscript): submitted within 12 months of data collection completion; publicly available 6 months post-publication

IPD will not be shared. Aggregated results (manuscript) and SAP will be publicly and unrestrictedly available to all—academic researchers, industry professionals, students, and the public—via the publishing journal and IRCT.

IPD will not be shared. For use of aggregated results and SAP: 1. Proper citation is mandatory. 2. Direct commercial use is not permitted. 3. Compliance with research ethics is required. 4. No formal request is needed due to open-access publication.

Applicants, in order of priority: 1. Publishing journal website (manuscript). 2.. Principal investigator email: mohamad.sorani@gmail.com (additional information). 3. PubMed, Scopus, and Google Scholar.

No application process. Immediate, free download from journal website or Email inquiries