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

This is a pilot study to consider whether post-operative pain management (following right hemicolectomy surgery using a lateral transverse incision) with continuous ropivacaine infusion using an elastomeric infusion pump (ON-Q Painbusterÿ¿??ÿ¿?ÿ¿ÿ®) for 96hr (rather than epidural) is safe, based on the margin between steady-state plasma ropivacaine concentrations attained (in particular, the unbound concentrations) and the systemic toxicity threshold(s). Whilst this device and local anaesthetic approach are currently used for post-op pain management, common usage in Australia is currently limited to 48-hr post-op.