The Efficacy and Safety of Liposomal Bupivacaine in Relieving Postoperative Pain After Hemorrhoid Surgery

The Efficacy and Safety of Liposomal Bupivacaine Plus Bupivacaine Local Incisional Infiltration for Postoperative Pain in Patients Undergoing Hemorrhoid Surgery:A Multi-Center Randomized Controlled Trial

Hemorrhoids represents the most prevalent condition among anorectal disorders. Due to the unique anatomical characteristics of the perianal region, patients frequently experience severe postoperative pain, which may lead some individuals to delay treatment due to pain-related anxiety. Consequently, effective postoperative pain management is critical for the recovery of hemorrhoid patients. Developing a simplified, efficient, and safe analgesic approach to alleviate postoperative pain has become an urgent issue in perioperative care. Multimodal analgesia regimens recommend the combined use of local anesthetics to synergistically reduce perioperative pain intensity. However, the primary limitation of this analgesic modality lies in the relatively short duration of action following a single injection of local anesthetic.Liposomal bupivacaine is an innovative long-acting, extended-release amide-type local anesthetic that provides analgesic efficacy for up to 72 hours. However, its efficacy and safety for local infiltration analgesia following hemorrhoid surgery have not been fully validated. Against this backdrop, the present study aims to evaluate and compare the clinical outcomes and safety profile of liposomal bupivacaine versus conventional bupivacaine for postoperative pain management via local infiltration in patients undergoing Hemorrhoid surgery.

Inclusion Criteria:

1. Patients scheduled for elective Hemorrhoid Surgery under general anesthesia;
2. Ages 18 to 64 years old；
3. American Society of Anesthesiologists (ASA) physical status of I-III；
4. Glasgow Coma Scale (GCS) score of 15；
5. Patients must be able to understand the nature and potential personal consequences of the clinical trial, signing of the informed consent form.

Exclusion Criteria:

1. History of chronic pain syndrome of any cause.
2. Patients with heart conduction block (sinus block or atrioventricular block).
3. Patients with unstable coronary artery disease.
4. Patients with gastric ulcer or gastric bleeding.
5. Patients with diabetes and are being treated with insulin.
6. Subjects with coagulation dysfunction (prothrombin time or activated partial thromboplastin time is higher than the normal threshold) or patients who are taking oral anticoagulants for other medical reasons and have not stopped it before surgery, such as warfarin or new anticoagulants rivaroxaban or dabigatran.
7. Patients with abnormal liver function: alanine aminotransferase (ALT) and/or aspartate aminotransferase (AST) > 2× the upper limit of normal (ULN) or total bilirubin (TBIL) ≥ 1.5×ULN.
8. Patients with renal impairment (serum creatinine > 176 µmol/L) or receiving dialysis treatment within 28 days before surgery.
9. Patients with a history of diagnosed mental illness or currently taking psychotropic medication.
10. Excessive alcohol or drug abuse, chronic opioid use (more than 2 weeks or 3 days per week for more than 1 month), use of drugs with confirmed or suspected sedative or analgesic effects, or use of any painkiller within 24 h before surgery.
11. Pregnancy or breastfeeding.
12. Extreme body mass index (BMI) (< 15 or > 35).
13. Participation in another interventional trial that interferes with the intervention or outcome of this trial.
14. Patients with a history of allergy to local anaesthetics or one of the study drugs.