The study design is a prospective randomized, double-blind, controlled trial of patients who are undergoing elective unilateral inguinal herniorrhaphy at Ramathibodi Hospital during the period 1 July 2018 - 30 June 2020 The primary outcome is to study the effectiveness of Ketorolac injections in pain relief after herniorrhaphy surgery and the secondary outcome is to study the adverse effects and complications after injection of Ketorolac: anaphylactic shock, abnormal bleeding at surgical wound, gastrointestinal bleeding and acute kidney injury.
After approval by the ethics committee, patients scheduled for elective unilateral inguinal herniorrhaphy under general anesthesia who are eligible for inclusion criteria will be recruited for this study after informed consent by surgical residents or surgical staff at the Out Patient Department (OPD). Patients who meet the exclusion criteria will be excluded.
During a preoperative visit, the patients will be introduced to the concept of the visual analogue scale (VAS), which ranges from 0 = no pain to 10 = worst pain.
Once given general anesthesia in the operating room, the patient will be randomly selected into one of the two arms of this report's diagram (1:1 ratio) through the drawing of a sealed, opaque envelope by one of the surgical residents in charge or by the attending surgeon. All patients will undergo herniorrhaphy with Lichtenstein Tension-Free Repair technique. After abdominal sheath will be closed by Vicryl No.0, Patients who are the Ketorolac group will receive local infiltration in abdominal sheath layer with Ketorolac 30 mg in normal saline 10 ml. and patients who are the control group will receive local infiltration with 0.5% bupivacaine 10 ml. And then skin closure will be done by nylon 3-0.
A standardized plan for postoperative analgesia is prepared. All patients will receive one 500 mg tablet of oral paracetamol every 6 hours when postoperative oral intake is allowed by the attending doctor. In patients with VAS scores \>3, parenteral opioid (Morphine) is given.
The hospital volunteer nurses caring for the patients during the preoperative and postoperative course are given standard pain evaluation protocols. All study pain evaluators and patients are blinded to treatment assignments throughout the pain assessment process.
After the operation, the inpatient ward nurse will record the patients' pain scores at 4,8, and 12 hours after surgery using the VAS score and record the results in the study data recording form attached to each patient's medical record chart. Additional morphine usage data is also recorded.
All adverse effects and complications after injection of Ketorolac injection such as anaphylactic shock, abnormal bleeding at surgical wound, gastrointestinal bleeding and acute kidney injury will be recorded and treated by the attending resident or consultant doctor. All data is collected by the main investigator from the patient chart and data recording form. Data is expressed as mean ± SD. Parametric data is compared between groups. Statistical significance is set at a level of p\< 0.05.
