['healthy']
['dexmedetomidine perineurally', 'ropivacaine 5mg/ml', 'ropivacaine 7.5mg/ml', 'dexmedetomidine systemically', 'isotonic saline']

        Inclusion Criteria:

          -  Participants must understand the protocol fully and sign the written in-formed
             consent.

          -  ASA 1-2

          -  BMI > 18 to < 30

          -  For fertile women: safe contraceptives for the last month and a nega-tive urin HCG.

        Exclusion Criteria:

          -  Participants unable to cooperate in the trial.

          -  Participants unable to speak or read Danish

          -  Allergy to study medication.

          -  Alcohol consumption >21 units for men and >14 for women per week

          -  Daily intake of prescription painkillers within the last 4 weeks.

          -  Over the counter painkillers during the last 48 hours.

          -  Neuromuscular defects or wounds on the arms or hands preventing test performance.

          -  Diabetes Mellitus

          -  2. degree heart block

          -  Sick sinus node.

          -  For fertile women a positive urine HCG
      