Described herein are methods and devices for selectively applying fluids (particularly anesthetics) to a target tissue from within a blood vessel while minimizing the amount of fluid applied to non-target tissue. The injection catheters described herein may include an elongate body, a directional injector, and one or more holdfasts for securing the catheter before extending the injector. The methods of selectively applying anesthetic to a target structure generally include the steps of inserting an injection catheter into a body vessel, positioning the injection catheter within the body vessel near the target structure, anchoring the injection catheter before extending a directional injector from the injection catheter, and applying anesthetic from the injection catheter to the target structure.