Effect of Dexmedetomidine on Nol-Index Guided Remifentanil Analgesia

Patients in the dexmedetomidine-remifentanil group will receive an infusion of 0.6 mcg/kg in half an hour followed by an infusion of 0.6 mcg/kg/hour.

Patients in the remifentanil group will receive an infusion of 0.9% sodium chloride instead of dexmedetomidine (identical infusion rate)

Both groups will have remifentanil analgesia guided by the Nol-Index