Lidocaine is a local anesthetic which is widely used in daily anesthesia and surgical practice. It has been shown that intravenous lidocaine given during an operation has analgesic properties. Finally intravenous lidocaine is inexpensive and easy to administer and safe if non-toxic doses are respected. It is likely that the use of lidocaine infusions during anesthesia might increase in the coming years. Neuromuscular blockers (curare like substances) are used in anesthesia to facilitate tracheal intubation and to achieve muscle relaxation and immobility during surgery. Rocuronium is one of the most widely used neuromuscular blocking agents. Local anesthetics, such as lidocaine, are known to potentiate the effect of neuromuscular blocking agents. In the study the investigators want to evaluate the effect of intravenous lidocaine during the operation on the time course of the rocuronium-induced neuromuscular block. A secondary aim is to evaluate intubation conditions (lidocaine has been shown also to improve intubation conditions) and safety.