A preliminary safety study comparing the concentration of a local anaesthetic absorbed into the blood (when trickling near the surgical site for 96hours after surgery) to published threshold for toxicity

Interventions: Pain management with local anaesthetic (ropivacaine) continuous infusion during- & post-op using ON-Q pain Buster device. Primary outcome(s): Safety of LA[serial blood sampling 0-96hr of local anaesthetic administration] Study Design: Purpose: Treatment; Allocation: Non-randomised trial; Masking: Open (masking not used);Assignment: Single group;Type of endpoint: Safety