RCT on the Effect of Dexmedetomidine as an Adjuvant to Ropivacaine in Ultrasound Guided Fascia Iliaca Block for Postoperative Analgesia Following Hemi-Arthroplasty

Abstract

Introduction: Fascia Iliaca Compartment Block (FICB) has been employed for post-operative pain relief after hip surgeries. Dexmedetomidine has been found to prolong effect of peripheral nerve blocks but its effect has not been adequately evaluated for FICB. Aim: To study the effect of addition of dexmedetomidine for FICB. Materials and Methods: The study was conducted at a tertiary level hospital in a randomised double blinded manner. Sixty adult American Society of Anaesthesiologists (ASA) Physical Class I-III patients of either sex scheduled for elective hemiarthroplasty under spinal anaesthesia, were included in the study after ethics committee approval and written informed consent. Patients were administered ultrasound guided FICB in operation theatre at the end of surgery. Group A patients were administered FICB by injecting 3 mg/kg of ropivacaine whereas, Group B patients received FICB using 3 mg/kg of ropivacaine along with 1 µg/kg dexmedetomidine as an adjuvant, making injectate volume of 40 mL in each group by the addition of normal saline. Post-operative pain scores using Visual Analogue Scale (VAS) and total rescue analgesic consumption were recorded in both the groups. Observation data obtained was tabulated and analysed statistically using Student’s t-test and Chi-square test. All statistical calculations were done using SPSS (Statistical Package for the Social Science) 21 version statistical program for Microsoft Windows and p-value less than 0.05 was considered to be significant. Results: Both groups were similar in their demographical profile and baseline haemodynamic parameters. Mean time of administration of first rescue analgesic was significantly earlier in group A at 275.29±226.31 minutes as compared to 465.8±325.56 minutes in group B. Similarly, group A patients needed rescue analgesic more frequently and mean total tramadol consumption was significantly higher in group A at 207.24±45.17 mg as compared to 145.56±48.31 mg in group B. There was no difference in the incidence of adverse effects between the two groups (p=0.072). Conclusion: The addition of dexmedetomidine to ropivacaine significantly prolongs the duration of analgesic effect of FICB without any adverse effects.

Keywords

• hemi-arthroplasty pain
• hip surgery
• nerve block
• pain
• subarachnoid block