Effect of Adding Dexamethasone to Bupivacaine in Ultrasound Guided Adductor Canal Block for Post-operative Analgesia Following Knee Arthroscopy

Abstract Background Arthroscopic knee surgery refers to a large variety of surgical interventions in the knee, and numerous analgesic regimens have been investigated in order to find the best combination of analgesics for these procedures. The post-operative pain response depends on the type and duration of surgical intervention, and it can be challenging to predict which analgesic regimen will be the most appropriate for each patient until after surgery. Aim of the Work Assessing the effect of adding dexamethasone perineurally to bupivacaine in adductor canal block for post operative analgesia following knee arthroscopy under spinal anaesthesia regarding; duration of postoperative analgesia as a primary objective and one-day postoperative analgesic and opioid consumption as a secondary objective. Patients and Methods The type of study was a randomized prospective double blinded controlled clinical trial at Ain Shams University Hospitals, Cairo, Egypt. Study Period: Six months, Adult patients undergoing Knee Arthroscopy under Spinal Anaesthesia will be randomly assigned into one of the following groups using computer generated codes and opaque sealed envelopes: Group A (study group): The patients received ACB with 20 ml plain bupivacaine (0.25%) + 8 mg dexamethasone (2 ml), Group B (control group): The patients received ACB with 20 ml plain bupivacaine (0.25%) + 2 ml of Normal saline. Results There was a highly statistically significant difference between groups according to analgesic duration (time of first call for analgesics) (min) with p-value (p < 0.001). The highest value was found in group A(study) and group B(control) (241.02±36.15 and 188.49±28.27) respectively, this indicates that that the needs of analgesic in the group B were earlier compared to group A. There was a highly statistically significant difference between groups according to cumulative morphine consumption “mg” with p-value (p < 0.001). The highest value was found in Group B and Group A 4 (3-4) and 2 (1-2) respectively, this indicates much higher needs of analgesic in the Group B than group A. Conclusion We concluded that ACB is a good postoperative analgesic choice for arthroscopic knee surgery under spinal anaesthesia. However, adding (8 mg)dexamethasone to(0.25%) bupivacaine in ACB provided better prolonged postoperative analgesia and less analgesic consumption than bupivacaine alone.