Misra, SatyajeetKoshy, ThomasSuneel, Puthuvassery Raman2012-12-042012-12-042009JOURNAL OF NEUROSURGICAL ANESTHESIOLOGY. 21; 4; 297-301https://dspace.sctimst.ac.in/handle/123456789/820Background: Scalp infiltration with epinephrine-lidocaine solution in patients undergoing neurosurgery may result in transient but significant hypotension. We investigated whether premedication with alpha(2)-adrenoreceptor agonist clonidine, which also exhibits alpha(1)-adrenoreceptor mediated vasoconstriction, would prevent or attenuate this fall in mean arterial pressure (M A P).Methods: Sixty-six American Society of Anesthesiologists 1 and 11 adult patients, 18 to 50 years, undergoing elective tumor decompression were recruited into this prospective, randomized, double-blind, placebo controlled study, and scheduled to receive either oral pantoprazole 40 mg (placebo group) or oral clonidine 3 mu g/kg (clonidine group), 90 minutes before induction of anesthesia. Primary end points studied were heart rate (HR) and MAP in both groups measured just before scalp infiltration (preinfiltration baseline) and then every 30 seconds for 5 minutes after initiation of scalp infiltration with 2.5 mu g/mL epinephrine contained in 15 in L of 1%, lidocaine solution.Results: There was no significant change in HR in the 2 groups during the study period compared with baseline values; however, patients in clonidine group had significantly lower HR compared with placebo (*P < 0.05). In both groups, MAP fell significantly below baseline I minute after start of infiltration. It recovered in the clonidine group after 2.5 minutes but not in the placebo group where it continued to remain low even at 5 minutes. MAP in the placebo group was also significantly lower compared with the clonidine group from 2.5 minutes to 5 minutes.Conclusion: In conclusion, oral clonidine 3 mu g/kg administered 90 minutes before induction of anesthesia attenuates the fall in MAP due to scalp infiltration with a dilute concentration of epinephrine-lidocaine solution in patients undergoing craniotomy under isoflurane anesthesia.