Intravenous Dexamethasone (0 vs 4 vs 8 mg) as an Adjunct to PENG Block for Postoperative Analgesia in Total Hip Arthroplasty: A Randomized Double-Blind Trial

his study will test whether giving dexamethasone through a vein can improve pain control after total hip replacement surgery. Dexamethasone is commonly used to reduce nausea and may also help with pain, but it is not clear which dose works best. Patients will be randomly assigned to receive either no dexamethasone, 4 mg, or 8 mg, in addition to standard anesthesia and a nerve block (PENG block). The main goal is to see how long patients go without needing additional pain medication after surgery. The study will also look at pain levels, use of opioid painkillers, nausea and vomiting, blood sugar levels, and possible side effects.

Inclusion Criteria: * Age ≥ 18 years * Scheduled for elective total hip arthroplasty (THA) * Planned use of regional anesthesia including PENG block * American Society of Anesthesiologists (ASA) physical status I-III * Ability to understand the study procedures and provide written informed consent * Ability to assess pain using the Numeric Rating Scale (NRS) Exclusion Criteria: * Known hypersensitivity to dexamethasone or any component of the study medication * Chronic corticosteroid therapy or use of systemic steroids within 14 days prior to surgery * Active systemic infection or sepsis * Significant immunosuppression (e.g., chemotherapy, biological therapy) * Pregnancy or breastfeeding * Severe cognitive impairment or inability to reliably assess pain * Uncontrolled diabetes mellitus (e.g., HbA1c \> 8.5% or baseline blood glucose \> 200 mg/dL)