Fentanyl Vs Dexmedetomidine Nebulization as Adjuvant to Lignocaine: A Comparative Study during Awake Flexible Fiberoptic Bronchoscopy

Background: Awake flexible fiberoptic bronchoscopy (AFFB) is a critical procedure in respiratory medicine, necessitating optimal patient comfort and minimal discomfort. Fentanyl and dexmedetomidine, known for their analgesic and sedative properties respectively, are investigated as adjuvants to lignocaine to enhance procedural efficacy and patient tolerance. Methods: This double-blind, randomized study involved 90 ASA Physical Status I/II patients, undergoing AFFB at a tertiary center from November 2018 to March 2020. Participants were divided into three groups: Fentanyl with lignocaine, dexmedetomidine with lignocaine, and lignocaine alone. Primary outcomes measured included mean arterial pressure (MAP), Ramsay Sedation Score (RSS), additional doses of lignocaine, and rescue doses of propofol required during the procedure. Results: Significant differences were noted in MAP and RSS between the fentanyl and dexmedetomidine groups, particularly during and after the procedure. Dexmedetomidine group showed better sedation depth (80% reaching RSS level 3, p<0.001) and stability in MAP compared to the fentanyl group, which showed higher variability and rescue propofol requirements. Additional lignocaine requirements were also lower in the dexmedetomidine group (21.30 mg) compared to the fentanyl group (28.40 mg, SD 10.39, p=0.019). Conclusion: Dexmedetomidine as an adjuvant to lignocaine in AFFB is superior to fentanyl in providing stable hemodynamic profiles, deeper sedation levels, and reduced need for additional sedation and local anesthetic. These findings support the use of dexmedetomidine over fentanyl to improve patient comfort and procedural outcomes in AFFB.