Background: Traumatic brain injury (TBI) is brain injury triggered by extrinsic mechanical stress leading to behavioral, cognitive, physical, and emotional symptoms. The current study aim was evaluating the impact of dexmedetomidine versus midazolam on intra cranial pressure through ultrasonographic assessment of optic nerve sheath diameter (ONSD) in cases of TBI.

Methods: This randomized clinical trial study was performed on one hundred thirty-six TBI cases who were divided equally into; Group dexmedetomidine (Group DEX): 68 patients received a loading dose of DEX (1 µg/kg over 10 minutes) followed by a maintenance infusion dose (0.2-0.7 µg/kg/h) for 24 hours as a sedative agent. Group Midazolam (Group MDZ): 68 patients received a loading dose of Midazolam (0.05-0.1 mg/kg) followed by a maintenance infusion dose (30-120 mcg/kg/hr) for 24 hours as a sedative agent. All cases were subjected to clinical assessment and laboratory, and ONSD examination.

Results: Right and left ONSD post sedation at (at 6, 12, 18 and 24h) were significantly lower in DEX group compared to MDZ group (P<0.05). HR at 6 h, 12 and 18 h post sedation was notably reduced in DEX group compared to MDZ group (P=0.004, <0.001, <0.001 respectively). Concerning the adverse events, vomiting occurred in 3 (4.41%) cases in group D and 5 (7.35%) cases in group M, hypotension occurred in only 7 (10.29%) cases in group D and not reported in group M.

Conclusion: dexmedetomidine may be a more effective sedative option for reducing ICP in TBI patients compared to midazolam.